NLIGHT, INC., 10-K filed on 2/26/2024
Annual Report
v3.24.0.1
Cover - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2023
Feb. 21, 2024
Jun. 30, 2023
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2023    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-38462    
Entity Registrant Name NLIGHT, INC.    
Entity Incorporation, Date of Incorporation DE    
Entity Tax Identification Number 91-2066376    
Entity Address, Address Line One 4637 NW 18th Avenue    
Entity Address, City or Town Camas    
Entity Address, State or Province WA    
Entity Address, Postal Zip Code 98607    
City Area Code 360    
Local Phone Number 566-4460    
Title of 12(b) Security Common Stock, par value$0.0001 per share    
Trading Symbol LASR    
Security Exchange Name NASDAQ    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Accelerated Filer    
Smaller Reporting Company false    
Emerging Growth false    
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Public Float     $ 696.6
Entity Common Stock, Shares Outstanding   47,289,419  
Documents Incorporated by Reference Portions of the registrant's definitive Proxy Statement for the 2024 Annual Meeting of Stockholders are incorporated herein by reference in Part III of this Annual Report on Form 10-K to the extent stated herein. Such Proxy Statement will be filed with the Securities and Exchange Commission within 120 days of the registrant's fiscal year ended December 31, 2023.    
Entity Central Index Key 0001124796    
Document Fiscal Year Focus 2023    
Document Fiscal Period Focus FY    
Amendment Flag false    
v3.24.0.1
Audit Information
 12 Months Ended
Dec. 31, 2023
Audit Information [Abstract]  
Auditor Firm ID 185
Auditor Name KPMG LLP
Auditor Location Portland, Oregon
v3.24.0.1
Consolidated Balance Sheets - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Current assets:    
Cash and cash equivalents $ 53,210 $ 57,826
Marketable securities 59,672 50,391
Accounts receivable, net of allowances of $315 and $290 39,585 37,913
Inventory 52,160 67,600
Prepaid expenses and other current assets 15,927 17,026
Total current assets 220,554 230,756
Restricted cash 256 252
Lease right-of-use assets 12,616 13,893
Property, plant and equipment, net 52,300 60,693
Intangible assets, net 1,652 4,041
Goodwill 12,399 12,376
Other assets, net 7,026 7,222
Total assets 306,803 329,233
Current liabilities:    
Accounts payable 12,166 17,507
Accrued liabilities 12,556 12,820
Deferred revenues 4,849 1,407
Current portion of lease liabilities 3,181 2,758
Total current liabilities 32,752 34,492
Non-current income taxes payable 5,391 6,699
Long-term lease liabilities 10,978 12,852
Other long-term liabilities 3,263 4,345
Total liabilities 52,384 58,388
Stockholders' equity:    
Common stock - $0.0001 par value; 190,000 shares authorized, 47,266 and 45,629 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively 16 16
Additional paid-in capital 521,184 496,211
Accumulated other comprehensive loss (2,477) (2,748)
Accumulated deficit (264,304) (222,634)
Total stockholders’ equity 254,419 270,845
Total liabilities and stockholders’ equity $ 306,803 $ 329,233
v3.24.0.1
Consolidated Balance Sheets (Parenthetical) - USD ($)
shares in Thousands, $ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Statement of Financial Position [Abstract]    
Accounts receivable, net of allowances $ 315 $ 290
Common stock, par value (in dollars per share) $ 0.0001 $ 0.0001
Common stock, shares authorized (in shares) 190,000 190,000
Common stock, shares issued (in shares) 47,266 45,629
Common stock, shares outstanding (in shares) 47,266 45,629
v3.24.0.1
Consolidated Statements of Operations - USD ($)
shares in Thousands, $ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Total revenue $ 209,921 $ 242,058 $ 270,146
Total cost of revenue 163,808 191,237 192,839
Gross profit 46,113 50,821 77,307
Operating expenses:      
Research and development 46,163 53,773 54,814
Sales, general, and administrative 45,899 48,258 52,710
Restructuring 817 3,892 0
Total operating expenses 92,879 105,923 107,524
Loss from operations (46,766) (55,102) (30,217)
Other income (expense):      
Interest income (expense), net 1,342 529 (163)
Other income, net 2,776 338 336
Loss before income taxes (42,648) (54,235) (30,044)
Income tax expense (benefit) (978) 344 (375)
Net loss $ (41,670) $ (54,579) $ (29,669)
Net loss per share, basic (in dollars per share) $ (0.90) $ (1.23) $ (0.70)
Net loss per share, diluted (in dollars per share) $ (0.90) $ (1.23) $ (0.70)
Shares used in per share calculations, basic (in shares) 46,078 44,436 42,142
Shares used in per share calculations, diluted (in shares) 46,078 44,436 42,142
Products      
Total revenue $ 156,666 $ 192,658 $ 206,195
Total cost of revenue 114,181 145,272 132,867
Development      
Total revenue 53,255 49,400 63,951
Total cost of revenue $ 49,627 $ 45,965 $ 59,972
v3.24.0.1
Consolidated Statements of Comprehensive Loss - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Statement of Comprehensive Income [Abstract]      
Net loss $ (41,670) $ (54,579) $ (29,669)
Other comprehensive loss, net of tax:      
Foreign currency translation adjustments (249) (2,555) (328)
Unrealized gains on available-for-sale securities 520 394 0
Comprehensive loss $ (41,399) $ (56,740) $ (29,997)
v3.24.0.1
Consolidated Statements of Stockholders' Equity - USD ($)
shares in Thousands, $ in Thousands
Total
Common stock
Additional paid-in capital
Accumulated other comprehensive loss
Accumulated deficit
Beginning balance (in shares) at Dec. 31, 2020   39,793      
Beginning balance at Dec. 31, 2020 $ 219,914 $ 15 $ 358,544 $ (259) $ (138,386)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Net loss (29,669)       (29,669)
Proceeds from follow-on offering, net of offering costs (in shares)   2,537      
Proceeds from follow-on offering, net of offering costs 82,354   82,354    
Issuance of common stock pursuant to exercise of stock options (in shares)   896      
Issuance of common stock pursuant to exercise of stock options 1,145   1,145    
Issuance of common stock pursuant to vesting of restricted stock awards and units, net of stock withheld for tax (in shares)   952      
Issuance of common stock pursuant to vesting of restricted stock awards and units, net of stock withheld for tax (10,606)   (10,606)    
Issuance of common stock under the Employee Stock Purchase Plan (in shares)   70      
Issuance of common stock under the Employee Stock Purchase Plan 1,603   1,603    
Stock-based compensation 37,720   37,720    
Cumulative translation adjustment, net of tax (328)     (328)  
Ending balance (in shares) at Dec. 31, 2021   44,248      
Ending balance at Dec. 31, 2021 302,133 $ 15 470,760 (587) (168,055)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Net loss (54,579)       (54,579)
Issuance of common stock pursuant to exercise of stock options (in shares)   585      
Issuance of common stock pursuant to exercise of stock options 1,198 $ 1 1,197    
Issuance of common stock pursuant to vesting of restricted stock awards and units, net of stock withheld for tax (in shares)   705      
Issuance of common stock pursuant to vesting of restricted stock awards and units, net of stock withheld for tax (4,861)   (4,861)    
Restricted stock awards forfeited in connection with transition agreement (in shares)   (140)      
Restricted stock awards modified in connection with performance achievement (in shares)   (10)      
Issuance of common stock under the Employee Stock Purchase Plan (in shares)   241      
Issuance of common stock under the Employee Stock Purchase Plan 2,358   2,358    
Stock-based compensation 26,757   26,757    
Unrealized gains on available-for-sale securities 394     394  
Cumulative translation adjustment, net of tax $ (2,555)     (2,555)  
Ending balance (in shares) at Dec. 31, 2022 45,629 45,629      
Ending balance at Dec. 31, 2022 $ 270,845 $ 16 496,211 (2,748) (222,634)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Net loss $ (41,670)       (41,670)
Proceeds from follow-on offering, net of offering costs (in shares) 1,700        
Issuance of common stock pursuant to exercise of stock options (in shares) 428 428      
Issuance of common stock pursuant to exercise of stock options $ 640   640    
Issuance of common stock pursuant to vesting of restricted stock awards and units, net of stock withheld for tax (in shares)   946      
Issuance of common stock pursuant to vesting of restricted stock awards and units, net of stock withheld for tax $ (3,968)   (3,968)    
Issuance of common stock under the Employee Stock Purchase Plan (in shares) 263 263      
Issuance of common stock under the Employee Stock Purchase Plan $ 2,469   2,469    
Stock-based compensation 25,832   25,832    
Unrealized gains on available-for-sale securities 520     520  
Cumulative translation adjustment, net of tax $ (249)     (249)  
Ending balance (in shares) at Dec. 31, 2023 47,266 47,266      
Ending balance at Dec. 31, 2023 $ 254,419 $ 16 $ 521,184 $ (2,477) $ (264,304)
v3.24.0.1
Consolidated Statements of Cash Flows - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Cash flows from operating activities:      
Net loss $ (41,670) $ (54,579) $ (29,669)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:      
Depreciation 12,401 11,085 9,179
Amortization 3,629 4,614 5,880
Reduction in carrying amount of right-of-use assets 1,269 3,000 3,253
Provision for losses on accounts receivable 27 4 (70)
Stock-based compensation 25,832 26,757 37,720
Deferred income taxes 7 4 37
Loss on disposal of property, plant and equipment 542 51 16
Non-cash restructuring charges 0 2,758 0
Changes in operating assets and liabilities:      
Accounts receivable, net (1,677) 2,757 (9,509)
Inventory 14,890 4,623 (18,994)
Prepaid expenses and other current assets 1,109 (1,753) (3,630)
Other assets, net (1,156) (5,219) (570)
Accounts payable (4,503) (5,904) 3,463
Accrued and other long-term liabilities (1,336) (577) (199)
Deferred revenues 3,432 (208) (909)
Lease liabilities (1,449) (1,942) (2,934)
Non-current income taxes payable (1,256) (13) (507)
Net cash provided by (used in) operating activities 10,091 (14,542) (7,443)
Cash flows from investing activities:      
Acquisition of business, net of cash acquired 0 (664) (291)
Purchases of property, plant and equipment (5,339) (21,388) (19,317)
Acquisition of intangible assets and capitalization of patents 0 (332) (2,245)
Purchase of marketable securities (127,907) (99,985) 0
Proceeds from maturities and sales of marketable securities 119,146 49,988 0
Net cash used in investing activities (14,100) (72,381) (21,853)
Cash flows from financing activities:      
Principal payments on term loan, debt and financing leases 0 0 (428)
Payment of contingent consideration related to acquisition 0 0 (326)
Proceeds from public offering, net of offering costs 0 0 82,354
Proceeds from employee stock plan purchases 2,469 2,358 1,603
Proceeds from stock option exercises 640 1,197 1,145
Tax payments related to stock award issuances (3,968) (4,861) (10,606)
Net cash provided by (used in) financing activities (859) (1,306) 73,742
Effect of exchange rate changes on cash 256 (477) (235)
Net increase (decrease) in cash, cash equivalents, and restricted cash (4,612) (88,706) 44,211
Cash, cash equivalents, and restricted cash, beginning of period 58,078 146,784 102,573
Cash, cash equivalents, and restricted cash, end of period 53,466 58,078 146,784
Supplemental disclosures:      
Cash paid for interest 40 0 117
Cash paid for income taxes 256 442 526
Operating cash outflows from operating leases 3,850 3,925 3,513
Right-of-use assets obtained in exchange for lease liabilities 1,716 1,349 8,012
Accrued purchases of property, equipment and patents $ 745 $ 207 $ 2,522
v3.24.0.1
Basis of Presentation and Significant Accounting Policies
 12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]  
Basis of Presentation and Significant Accounting Policies Basis of Presentation and Significant Accounting Policies
Basis of Presentation
The accompanying consolidated financial statements include the accounts of nLIGHT, Inc. and our wholly owned subsidiaries Arbor Photonics, LLC, nLIGHT Cayman Ltd., nLIGHT Laser Technology (Shanghai) Co. Ltd, nLIGHT Oy (Finland), nLIGHT Korea Inc., nLIGHT GmbH, nLIGHT DEFENSE Systems Inc. (fka Nutronics, Inc.), and nLIGHT Europe S.r.l. All intercompany balances have been eliminated.

Use of Estimates
The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates, including those related to inventory valuation, allowances for doubtful accounts, warranty, sales return reserves and the recoverability of long-lived assets. Management bases its estimates on historical experience and on various other assumptions. Actual results could differ from those estimates.

Revenue Recognition
See Note 2 for a detailed description of our revenue recognition policies.

Cash and Cash Equivalents
We consider all highly liquid investments with an original maturity of three months or less when acquired to be cash equivalents. Cash and cash equivalents included $24.4 million and $32.3 million of highly liquid investments at December 31, 2023 and 2022, respectively. Cash equivalents are carried at cost, which approximates fair value.

Inventory
See Note 7 for a detailed description of our inventory accounting policies.

Property, Plant and Equipment
Property, plant and equipment are stated at cost, net of accumulated depreciation. Improvements and replacements are capitalized. Repair and maintenance costs are expensed as incurred. Depreciation is computed using the straight‑line method over the estimated useful life of each asset, generally 2 to 12 years for property and equipment, and 30 years for buildings. Land is not depreciated.

Goodwill
Goodwill is recorded when the purchase price of an acquisition exceeds the fair value of the net assets acquired. Goodwill is not amortized and is tested for impairment at least annually and more frequently if material changes in events or circumstances arise. We perform an annual impairment review of goodwill in the fourth quarter of each year using either a qualitative assessment or a quantitative goodwill impairment test. If the qualitative assessment is selected and determines that the fair value of each reporting unit more likely than not exceeds its carrying value, no further assessment is necessary. If a quantitative test is determined necessary and an impairment is indicated, the impairment loss is recorded to the extent that the reporting unit’s carrying amount exceeds the reporting unit’s fair value. An impairment loss cannot exceed the total amount of goodwill allocated to the reporting unit. Based on qualitative assessments performed in fiscal years 2023, 2022 and 2021, the fair values of the Laser Products and Advanced Development reporting units exceeded their carrying values, and no impairment charges were recorded. See Note 9 for additional information.

Intangible Assets
Definite-lived intangible assets consist of acquisition-related development programs, developed technology, and intellectual property. The intangible assets are being amortized using the straight-line method over periods of 2 to 5 years, which reflect the pattern in which economic benefits of the assets are expected to be realized. See Note 9 for additional information.
Other Assets
Other assets, net primarily consist of long-term accounts receivable, demonstration ("demo") assets and deposits.

Demo assets are equipment that is used for demonstration and other purposes with existing and prospective customers. Demo assets are recorded at cost and amortized over an estimated useful life of approximately two years.

Amortization expense related to demo assets was as follows (in thousands):

Year Ended December 31,
 202320222021
Amortization expense$1,150 $1,544 $1,979 

Restructuring Charges
Restructuring charges in 2023 were comprised primarily of employee severance and in 2022 were comprised of employee severance and abandoned in-process capital equipment projects related to production capacity that were never placed into service.

The determination of when we accrue for employee termination benefits depends on whether the termination benefits are provided under a one-time benefit arrangement or under an on-going benefit arrangement. For restructuring charges recorded as an on-going benefit arrangement, a liability for post-employment benefits is recorded when payment is probable, the amount is reasonably estimable, and the obligation relates to rights that have vested or accumulated. For restructuring charges recorded as a one-time benefit arrangement, we recognize a liability for employee termination benefits when a plan of termination, approved by management and establishing the terms of the benefit arrangement, has been communicated to employees. The timing of the recognition of one-time employee termination benefits is dependent upon the period of time the employees are required to render service after communication. If employees are not required to render service in order to receive the termination benefits or if employees will not be retained to render service beyond the minimum legal notification period, a liability for the termination benefits is recognized at the communication date. In instances where employees will be retained to render service beyond the minimum legal notification period, the liability for employee termination benefits is measured initially at the communication date based on the fair value of the liability as of the termination date and is recognized ratably over the future service period. We continually evaluate the adequacy of the remaining liabilities under our restructuring initiatives.

We record charges related to long-lived assets to be abandoned when the assets cease to be used, and any inventory charges related to restructuring are classified as a cost of revenue.

Although we believe that these estimates accurately reflect the costs of our restructuring plans, actual results may differ, thereby requiring us to record additional provisions or reverse a portion of such provisions.

See Note 14 for additional information.

Impairment of Long‑Lived Assets
Long‑lived assets, such as property, plant and equipment, and intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the asset. There was no impairment of long‑lived assets recorded for the years ended December 31, 2023, 2022 and 2021.

Leases
See Note 13 for a detailed description of our lease accounting policies.

Research and Development Costs
Research and development is defined as activities aimed at developing or significantly improving a product or a process or technique whether the product or process is intended for sale or use. A process also may be used internally as a part of a manufacturing activity. Research and development costs are expensed as incurred.
Stock-Based Compensation
We recognize compensation expense for stock-based awards on a straight-line basis based on the grant-date estimated fair values and requisite service period. The fair value of stock options is measured using the Black-Scholes option pricing model, while the fair value of restricted stock units (RSU) and restricted stock awards (RSA) are measured based on the closing market price of our common stock on the date of grant. For RSUs and RSAs with performance conditions, compensation costs are also based on the probable outcome of achieving the specified performance conditions. The fair value of restricted stock awards based on certain market performance criteria is measured using the Monte Carlo simulation pricing model.

Income Taxes
We account for income taxes using the asset and liability approach under which deferred income taxes are provided based upon enacted tax laws and rates applicable to the periods in which taxes become payable.
We recognize the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely to be realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs.
Translation of Foreign Currencies
Our international subsidiaries use their local currency as their functional currency. The financial statements of the international subsidiaries are translated to their U.S. dollar equivalents at end‑of‑period currency exchange rates for assets and liabilities and at average currency exchange rates for revenues and expenses. Translation adjustments are recorded as a component of Accumulated other comprehensive loss within stockholders’ equity. Realized and unrealized foreign currency gains or losses, net are recorded in Other income, net within the Consolidated Statements of Operations. Realized and unrealized foreign currency gains and losses were as follows for the periods presented (in thousands):
Year Ended December 31,
 202320222021
Realized foreign currency gain$1,169 $(967)$(294)
Unrealized foreign currency loss(1,140)1,052 102 

New Accounting Pronouncements

ASU 2023-07
In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures. The amendments in this ASU are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We are currently evaluating the impact of this guidance on our consolidated financial statements.

ASU 2023-09
In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. This ASU requires enhanced jurisdictional and other disaggregated disclosures for the effective tax rate reconciliation and income taxes paid and is effective for fiscal years beginning after December 15, 2024. This ASU requires additional disclosures and, accordingly, we do not expect the adoption of ASU 2023-09 to have a material effect on our financial position, results of operations or cash flows.
v3.24.0.1
Revenue
 12 Months Ended
Dec. 31, 2023
Revenue from Contract with Customer [Abstract]  
Revenue Revenue
We recognize revenue upon transferring control of products and services and the amounts recognized reflect the consideration we expect to be entitled to receive in exchange for these products and services. We consider customer purchase orders, which in some cases are governed by master sales agreements, to be the contracts with a customer. As part of our consideration of the contract, we evaluate certain factors, including the customer's ability to pay (or credit risk). For each contract, we consider the promise to transfer products, each of which is distinct, as the identified performance obligations.

We allocate the transaction price to each distinct product based on its relative standalone selling price. Master sales agreements or purchase orders from customers could include a single product or multiple products. Regardless, the contracted price with the customer is agreed to at the individual product level outlined in the customer contract or purchase order. We do not bundle prices; however, we do negotiate with customers on pricing for the same
products based on a variety of factors (e.g., level of contractual volume). We have concluded that the prices negotiated with each individual customer are representative of the stand-alone selling price of the product.

We often receive orders with multiple delivery dates that may extend across several reporting periods. We allocate the transaction price of the contract to each delivery based on the product standalone selling price and invoice for each scheduled delivery upon shipment or delivery and recognize revenues for such delivery at that point, when transfer of control has occurred. As scheduled delivery dates are generally within one year, under the optional exemption provided by ASC 606-10-50-14a, revenues allocated to future shipments of partially completed contracts are not disclosed as performance obligations for point in time revenue. Further, we recognize, over time, revenue as per ASC 606-10-55-18 (invoice practical expedient) for our cost plus contracts and, accordingly, elect not to disclose information related to those performance obligations under ASC 606-10-50-14b. As of December 31, 2023, we had approximately $30 million of performance obligations relating to firm fixed price contracts that did not qualify for the aforementioned disclosure exemptions. We expect to recognize more than 80% of these performance obligations by the end of 2024 and the remainder in 2025.

Rights of return generally are not included in customer contracts. Accordingly, product revenue is recognized upon transfer of control at shipment or delivery, as applicable. Rights of return are evaluated as they occur.

Revenues recognized at a point in time consist of sales of semiconductor lasers, fiber lasers and other related products. Revenues recognized over time generally consist of development arrangements that are structured based on our costs incurred. For long-term contracts, we estimate the total expected costs to complete the contract and recognize revenue based on the percentage of costs incurred at period end. Typically, revenue is recognized over time using costs incurred to date relative to total estimated costs at completion to measure progress toward satisfying our performance obligations. Incurred costs represent work performed, which corresponds with, and thereby best depicts, the transfer of control to the customer. Contract costs include labor, materials, subcontractors costs, other direct costs, and indirect costs applicable on government and commercial contracts.

Contract estimates are based on various assumptions to project the outcome of future events that may span several
years. These assumptions include labor productivity and availability, the complexity of the work to be performed, the cost and availability of materials, the performance of subcontractors, and the availability and timing of funding from the customer. Billing under these arrangements generally occurs within one month of the costs being incurred or as milestones are reached.

The following tables represent a disaggregation of revenue from contracts with customers for the periods presented (in thousands):
    
Sales by End Market
Year Ended December 31,
 202320222021
Industrial$71,044 $91,098 $94,795 
Microfabrication47,483 62,769 70,412 
Aerospace and Defense91,394 88,191 104,939 
$209,921 $242,058 $270,146 
Sales by Geography

Year Ended December 31,
 202320222021
North America$129,311 $137,454 $143,232 
China11,890 21,287 55,446 
Rest of World68,720 83,317 71,468 
$209,921 $242,058 $270,146 

Sales by Timing of Revenue

Year Ended December 31,
 202320222021
Point in time$155,258 $183,005 $198,838 
Over time54,663 59,053 71,308 
$209,921 $242,058 $270,146 
Our contract assets and liabilities were as follows (in thousands):
Balance Sheet ClassificationAs of December 31,
 20232022$ Change% Change
Contract assetsPrepaid expenses and
other current assets		$7,298 $10,377 $(3,079)(30)%
Contract liabilitiesDeferred revenues and other long-term liabilities6,368 2,455 3,913 159 %

Contract assets generally consist of revenue recognized on an over-time basis where revenue recognition has been met, but the amounts are subsequently billed and collected in a subsequent period. In our services contracts, amounts are billed as work progresses in accordance with agreed-upon contractual terms, either at periodic intervals, which is generally monthly, or upon the achievement of contractual milestones. Generally, billing occurs subsequent to revenue recognition, resulting in contract assets recorded in prepaid expenses and other current assets on the Consolidated Balance Sheets. However, we sometimes receive advances or deposits from our customers before revenue is recognized, resulting in contract liabilities recorded in deferred revenue on the Consolidated Balance Sheets.

Contract liabilities are not a significant financing component as they are generally utilized to pay for contract costs within a one-year period or are used to ensure the customer meets contractual requirements. These assets and liabilities are reported on the Consolidated Balance Sheets on a contract-by-contract basis at the end of each reporting period. For our product revenue, we generally receive cash payments subsequent to satisfying the performance obligation via delivery of the product, resulting in billed accounts receivable. For our contracts, there are no significant gaps between the receipt of payment and the transfer of the associated goods and services to the customer for material amounts of consideration.

The changes in contract assets and liabilities primarily results from timing differences between revenue recognition and customer billings and/or payments. During the years ended December 31, 2023 and 2022, we recognized revenue of $1.5 million and $1.6 million, respectively, that was included in the deferred revenue balances at the beginning of the period as the performance obligations under the associated agreements were satisfied.
v3.24.0.1
Concentrations of Credit and Other Risks
 12 Months Ended
Dec. 31, 2023
Risks and Uncertainties [Abstract]  
Concentrations of Credit and Other Risks Concentrations of Credit and Other Risks
The following customer accounted for 10% or more of our revenues for the periods presented:
Year Ended December 31,
202320222021
U.S. Government*18%17%22%
*Excludes sales to customers who sell our products and services exclusively to the U.S. Government
Financial instruments that potentially expose us to concentrations of credit risk consist principally of receivables from customers. As of December 31, 2023 and 2022, two customers accounted for a total of 24% and 29%, respectively, of net customer receivables. No other customers accounted for 10% or more of net customer receivables at either date.
v3.24.0.1
Accounts Receivable
 12 Months Ended
Dec. 31, 2023
Receivables [Abstract]  
Accounts Receivable Accounts Receivable
Trade accounts receivable are recorded at the invoiced amount and do not bear interest. The allowance for doubtful accounts is our best estimate of the amount of probable credit losses in our existing accounts receivable. We determine the allowance based on historical write-off experience and knowledge of any applicable circumstances.
Activity related to the allowance for doubtful accounts was as follows for the periods presented (in thousands):
Year Ended December 31,
202320222021
Allowance for doubtful accounts, beginning$290 $303 $367 
Provision (benefit) for losses on accounts receivable27 27 (4)
Write-offs, net(2)(40)(60)
Allowance for doubtful accounts, ending$315 $290 $303 
v3.24.0.1
Marketable Securities
 12 Months Ended
Dec. 31, 2023
Investments, All Other Investments [Abstract]  
Marketable Securities Marketable Securities
Marketable securities consist primarily of highly liquid investments with original maturities of greater than 90 days when purchased. Our marketable securities are considered available-for-sale as they represent investments that are available to be sold for current operations. As such, they are included as current assets on our Consolidated Balance Sheets at fair value with unrealized gains and losses included in accumulated other comprehensive loss. Any unrealized gains and losses that are considered to be other-than-temporary are recorded in other income, net on our Consolidated Statements of Operations. Realized gains and losses on the sale of marketable securities are determined using the specific-identification method and recorded in other income, net on our Consolidated Statements of Operations.

Realized gains were $2.4 million and unrealized gains were $0.5 million for the year ended December 31, 2023. Realized gains were $0.2 million and unrealized gains were $0.4 million for the year ended December 31, 2022. These unrealized gains are considered temporary and are reflected in the Consolidated Statements of Comprehensive Loss.

See Note 6 for additional information.
v3.24.0.1
Fair Value of Financial Instruments
 12 Months Ended
Dec. 31, 2023
Fair Value Disclosures [Abstract]  
Fair Value of Financial Instruments Fair Value of Financial Instruments
The carrying amounts of certain of our financial instruments, including cash equivalents, accounts receivable, prepaid expenses and other current assets, accounts payable and accrued liabilities are shown at cost which approximates fair value due to the short-term nature of these instruments. The fair value of our term and revolving loans approximates the carrying value due to the variable market rate used to calculate interest payments.

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value which are the following:

•Level 1 Inputs: Observable inputs, such as quoted prices (unadjusted) in active markets for identical assets or liabilities at the measurement date.
•Level 2 Inputs: Observable inputs, other than Level 1 prices, such as quoted prices in active markets for similar assets and liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
•Level 3 Inputs: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Our financial instruments that are carried at fair value consist of Level 1 assets which include highly liquid investments and bank drafts classified as cash equivalents and marketable securities.

Our fair value hierarchy for our financial instruments was as follows (in thousands):
December 31, 2023
Level 1Level 2Level 3Total
Cash Equivalents:
  Money market securities $22,441 $— $— $22,441 
  Commercial paper1,995 — — 1,995 
24,436 — — 24,436 
Marketable Securities:
  U.S. treasuries59,672 — — 59,672 
Total$84,108 $— $— $84,108 
December 31, 2022
Level 1Level 2Level 3Total
Cash Equivalents:
  Money market securities$31,658 $— $— $31,658 
  Commercial paper656 — — 656 
32,314 — — 32,314 
Marketable Securities:
  U.S. treasuries50,391 — — 50,391 
Total$82,705 $— $— $82,705 

Cash Equivalents
The fair value of cash equivalents is determined based on quoted market prices for similar or identical securities.

Marketable Securities
We classify our marketable securities as available-for-sale and value them utilizing a market approach that uses observable inputs without applying significant judgment.
v3.24.0.1
Inventory
 12 Months Ended
Dec. 31, 2023
Inventory Disclosure [Abstract]  
Inventory Inventory
Inventory is stated at the lower of average cost (principally standard cost, which approximates actual cost on a first-in, first-out basis) and net realizable value. Inventory includes raw materials and components that may be specialized in nature and subject to obsolescence. On a quarterly basis, we review inventory quantities on hand in comparison to our past consumption, recent purchases, and other factors to determine what inventory quantities, if any, may not be sellable. Based on this analysis, we write down the affected inventory value for estimated excess and obsolescence charges. At the point of loss recognition, a new, lower-cost basis for that inventory is established, and subsequent changes in facts and circumstances do not result in the restoration or increase in that newly established cost basis.
Inventory consisted of the following (in thousands):
As of December 31,
20232022
Raw materials$23,426 $32,515 
Work in process and semi-finished goods19,640 19,056 
Finished goods9,094 16,029 
$52,160 $67,600 
v3.24.0.1
Property, Plant and Equipment
 12 Months Ended
Dec. 31, 2023
Property, Plant and Equipment [Abstract]  
Property, Plant and Equipment Property, Plant and Equipment
Property, plant and equipment consisted of the following (in thousands):
Useful lifeAs of December 31,
 (years)20232022
Automobiles3$109 $110 
Computer hardware and software
3 - 5
9,145 8,712 
Manufacturing and lab equipment
2 - 7
91,050 89,230 
Office equipment and furniture
5 - 7
2,634 2,410 
Leasehold and building improvements
2 - 12
31,988 30,675 
Buildings309,392 9,392 
LandN/A3,399 3,399 
147,717 143,928 
Accumulated depreciation (95,417)(83,235)
$52,300 $60,693 
v3.24.0.1
Intangible Assets and Goodwill
 12 Months Ended
Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]  
Intangible Assets and Goodwill Intangible Assets and Goodwill
Intangible Assets
The details of definite lived intangible assets were as follows (in thousands):
Estimated useful life
(in years) 		As of December 31,
 20232022
Patents
3 - 5
$6,345 $6,322 
Development programs
2 - 4
7,200 7,200 
Developed technology52,959 2,930 
16,504 16,452 
Accumulated amortization (14,852)(12,411)
$1,652 $4,041 

Amortization related to intangible assets was as follows (in thousands):
Year Ended December 31,
 202320222021
Amortization expense$2,410 $2,879 $3,891 

Estimated amortization expense for future years is as follows (in thousands):
2024$819 
2025484 
2026349 
Thereafter— 
$1,652 

Goodwill
The carrying amount of goodwill by segment was as follows (in thousands):
Laser ProductsAdvanced DevelopmentTotals
Balance, December 31, 2021$2,172 $10,248 $12,420 
Currency exchange rate adjustment(44)— (44)
Balance, December 31, 20222,128 10,248 12,376 
Currency exchange rate adjustment23 — 23 
Balance, December 31, 2023$2,151 $10,248 $12,399 
v3.24.0.1
Accrued Liabilities
 12 Months Ended
Dec. 31, 2023
Payables and Accruals [Abstract]  
Accrued Liabilities Accrued Liabilities
Accrued liabilities consisted of the following (in thousands):
As of December 31,
20232022
Accrued payroll and benefits$7,898 $8,233 
Product warranty, current3,339 2,601 
Other accrued expenses1,319 1,986 
$12,556 $12,820 
v3.24.0.1
Product Warranties
 12 Months Ended
Dec. 31, 2023
Guarantees and Product Warranties [Abstract]  
Product Warranties Product Warranties
We provide warranties on certain products and record a liability for the estimated future costs associated with warranty claims at the time revenue is recognized. The warranty liability is based on historical experience, any specifically identified failures, and our estimate of future costs. The current portion of our product warranty liability is included in the accrued liabilities and the long-term portion is included in Other long-term liabilities in our Consolidated Balance Sheets.

Product warranty liability activity was as follows for the periods presented (in thousands):
Year Ended December 31,
 20232022
Product warranty liability, beginning$5,441 $5,371 
Warranty charges incurred, net(3,788)(1,490)
Provision for warranty charges, net of adjustments2,816 1,560 
Product warranty liability, ending4,469 5,441 
Less: current portion of product warranty liability(3,339)(2,601)
Non-current portion of product warranty liability$1,130 $2,840 
v3.24.0.1
Commitments and Contingencies
 12 Months Ended
Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Leases
See Note 13.

Credit Facilities
We have a $40.0 million revolving line of credit (LOC) with Pacific Western Bank which is secured by our assets and expires in September 2024.

The LOC agreement contains restrictive and financial covenants and bears an unused credit fee of 0.20% on an annualized basis. The interest rate on the LOC is based on the Prime Rate, minus a margin based on our liquidity levels. No amounts were outstanding under the LOC at December 31, 2023 and 2022 and we were in compliance with all covenants.

Legal Matters
On March 25, 2022, Lumentum Operations LLC (Lumentum) filed a complaint against nLIGHT, Inc. and certain of its employees in the U.S. District Court for the Western District of Washington. The complaint alleges that Lumentum is the partial or full owner of certain of our patents and requests corresponding relief from the court. We are vigorously defending against Lumentum's allegations. Loss in this matter is not probable nor reasonably estimable, and, as such, no loss contingency has been recorded.

From time to time, we may be subject to various other legal proceedings and claims in the ordinary course of business. As of December 31, 2023, we believe these matters will not have a material adverse effect on our consolidated financial statements.
v3.24.0.1
Leases
 12 Months Ended
Dec. 31, 2023
Leases [Abstract]  
Leases Leases
We lease real estate space under non-cancelable operating lease agreements for commercial and industrial space. Facilities-related operating leases have remaining terms of 0.3 to 11.4 years, and some leases include options to extend up to 15 years. Other leases for automobiles, manufacturing and office and computer equipment have remaining lease terms of 0.2 to 4.8 years. These leases are primarily operating leases; financing leases are not material. We did not include any renewal options in our lease terms for calculating the lease liabilities as we are not reasonably certain we will exercise the options at this time. The weighted-average remaining lease term for the lease obligations was 7 years as of December 31, 2023, and the weighted-average discount rate was 3.8%.

The components of lease expense related to operating leases were as follows (in thousands):
Year Ended December 31,
202320222021
Lease expense:
Operating lease expense$3,671 $3,865 $3,924 
Short-term lease expense472 573 525 
Variable and other lease expense1,020 872 741 
$5,163 $5,310 $5,190 

Future minimum payments under our non-cancelable lease obligations were as follows as of December 31, 2023 (in thousands):
2024$3,687 
20252,408 
20261,741 
20271,688 
20281,413 
Thereafter5,410 
Total minimum lease payments16,347 
Less: interest(2,188)
Present value of net minimum lease payments14,159 
Less: current portion of lease liabilities(3,181)
Total long-term lease liabilities$10,978 
v3.24.0.1
Restructuring
 12 Months Ended
Dec. 31, 2023
Restructuring and Related Activities [Abstract]  
Restructuring Restructuring
During the fourth quarter of 2023, we implemented a restructuring plan which included headcount reduction in China. During the fourth quarter of 2022, we implemented a restructuring plan which included headcount reductions in both the U.S. and China, and the write-down of in-process capital equipment projects related to production capacity that was never placed into service. Restructuring charges in 2023 and 2022 were as follows (in thousands):
Year Ended December 31,
20232022
Employee termination costs$737 $1,271 
Write-down of long-lived assets— 2,566 
Other79 55 
Total restructuring charges$817 $3,892 
Restructuring accruals and payments in 2023 and 2022 were as follows (in thousands):
Accrued restructuring charges at December 31, 2021$— 
Restructuring charges3,892
Cash payments(1,134)
Non-cash settlements(2,566)
Accrual at December 31, 2022192 
Restructuring charges817
Cash payments(1,009)
Accrual at December 31, 2023$— 
The restructuring accrual was included as a component of Accrued liabilities on our Consolidated Balance Sheets. All of the restructuring charges recorded in 2023 were attributable to the Laser Products segment. Approximately $3.8 million of the charges recorded in 2022 were attributable to the Laser Products segment, with the remaining $0.1 million attributable to the Advanced Development segment.
v3.24.0.1
Income Taxes
 12 Months Ended
Dec. 31, 2023
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
Loss before income taxes was as follows (in thousands):
 Year Ended December 31,
202320222021
Domestic$(46,602)$(50,611)$(33,940)
Foreign3,954 (3,624)3,896 
Loss before income taxes$(42,648)$(54,235)$(30,044)
The income tax provision (benefit) was as follows (in thousands):
Year Ended December 31,
 202320222021
Current tax expense (benefit):
State$53 $73 $70 
Foreign(985)264 (458)
Current tax expense (benefit)(932)337 (388)
Deferred tax expense (benefit):
Foreign(46)7 13 
Deferred tax expense (benefit)(46)7 13 
Income tax expense (benefit)$(978)$344 $(375)

The income tax provision (benefit) differs from the amount computed by applying the statutory federal income tax rate of 21% to the loss before income taxes as a result of the following differences (in thousands):

Year Ended December 31,
 202320222021
Tax computed at federal statutory rate$(8,956)$(11,436)$(6,309)
State tax, net of federal tax benefit(800)(842)(407)
Permanent items(364)(522)(333)
Stock-based compensation1,923 4,005 (3,307)
Foreign dividends and unremitted earnings104 (231)78 
Foreign rate differential146 (360)29 
Rate change due to tax reform— — 918 
Federal credits(988)(445)(993)
Tax contingencies, net of reversals(1,177)256 838 
Return to provision(429)(523)(1,123)
Expiration of net operating loss carryforwards1,810 — — 
Other49 (324)(305)
Valuation allowance7,704 10,766 10,539 
Income tax expense (benefit)$(978)$344 $(375)

The income tax expense (benefit) recorded primarily relates to operations in China and Finland, which have income tax rates of 25% and 20%, respectively.
The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are as follows (in thousands):
Year Ended December 31,
 202320222021
Deferred tax assets:
Net operating loss carryforwards$39,714 $39,998 $35,585 
Research and alternative minimum tax credits7,822 6,658 6,535 
Accrued expenses and other4,365 4,999 7,020 
Lease liabilities2,854 3,270 3,525 
Inventory3,283 3,305 5,852 
Property and equipment387 293 — 
Intangible assets16,612 9,184 — 
Total gross deferred tax assets75,037 67,707 58,517 
Less: valuation allowance(72,461)(64,796)(54,239)
Total deferred tax assets2,576 2,911 4,278 
Deferred tax liabilities:
Property and equipment— — (87)
Intangible assets— — (767)
Right-of-use assets(2,487)(2,869)(3,378)
Total deferred tax liabilities(2,487)(2,869)(4,232)
Net deferred tax assets$89 $42 $46 
    
Net deferred tax assets are included in Other assets, net in our Consolidated Balance Sheets.

In evaluating our valuation allowance, we consider all available positive and negative evidence, including scheduled reversals of deferred tax liabilities, projected future taxable income, tax planning strategies, and recent financial performance. Due to uncertainty with respect to ultimate realizability of deferred tax assets, we have provided a full valuation allowance against the U.S. and China deferred tax assets. The net change in the total valuation allowance for the years ended December 31, 2023, 2022 and 2021 were increases of $7.7 million, $10.6 million and $10.6 million, respectively.
At December 31, 2023, we had U.S., China, and state net operating loss (NOL) carryforwards of $161.0 million, $14.5 million, and $43.2 million, respectively. These carryforwards will expire from 2024 to 2043 if not used by us to reduce taxable income in future periods. We have U.S. research and development credit carryforwards of $9.3 million. These carryforwards will begin to expire between 2024 and 2043 if not used by us to reduce income taxes payable in future periods.

Utilization of NOL carryforwards, credit carryforwards and certain deductions have been subject to annual limitations due to ownership change limitations provided by the Internal Revenue Code of 1986, as amended. We have had three "change in ownership" events that limit the utilization of NOL carryforwards, which occurred twice in August of 2000 and once in January of 2001, and resulted in NOL carryforward limitations totaling $528 thousand. Additional limitations on the use of these tax attributes could occur in the event of possible disputes arising in examination from various taxing authorities.
The following table presents a reconciliation of the changes in the unrecognized tax benefit (in thousands):

Balance at December 31, 2020$7,859 
Additions based on tax positions related to the current year661 
Additions for tax positions of prior years53 
Reductions as a result of a lapse of applicable statute of limitations(250)
Other112 
Balance at December 31, 20218,435 
Additions based on tax positions related to the current year822 
Reductions for tax positions of prior years(53)
Reductions as a result of a lapse of applicable statute of limitations(183)
Other(437)
Balance at December 31, 20228,584 
Additions based on tax positions related to the current year416 
Reductions for tax positions of prior years(70)
Reductions as a result of a lapse of applicable statute of limitations(371)
Other(84)
Balance at December 31, 2023$8,475 
    
At December 31, 2023, we had $8.5 million of unrecognized tax benefits (excluding interest and penalties). Of this amount, $2.8 million is recorded in non-current deferred tax liabilities and $5.7 million is recorded as an offset to non-current deferred tax assets on the accompanying Consolidated Balance Sheets. The $5.7 million of unrecognized tax benefits in non-current deferred tax assets is entirely offset by a valuation allowance in both the U.S. and China. Of our unrecognized tax benefits, $2.8 million, if recognized, would impact the effective tax rate. At December 31, 2022, we had $8.6 million of unrecognized tax benefits (excluding interest and penalties). Of this amount, $3.1 million was recorded in non-current income taxes payable and $5.5 million as an offset to non-current deferred tax assets on the accompanying Consolidated Balance Sheets. We do not expect a significant decrease to the total amount of unrecognized tax benefits within the next twelve months.

We recognize interest and penalties related to unrecognized tax benefits as a component of income tax expense. We recognized a net increase (decrease) in penalties and interest during the years ended December 31, 2023, 2022 and 2021, of $(1.0) million, $0.3 million, and $(0.3) million, respectively. At December 31, 2023 and 2022, interest and penalties associated with unrecognized tax benefits were $0.9 million and $2.0 million, respectively.
At December 31, 2023, our tax years 2020 through 2023, 2019 through 2023, and 2013 through 2023, remain open for examination in the federal, state and foreign jurisdictions, respectively. However, to the extent allowed by law, the taxing authorities may have the right to examine prior periods where net operating losses and credits were generated and carried forward, and to make adjustments up to the net operating loss and credit carryforward amounts. We are not currently under federal, state, or foreign tax examination.
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation
 12 Months Ended
Dec. 31, 2023
Equity [Abstract]  
Stockholders' Equity and Stock-Based Compensation Stockholders' Equity and Stock-Based Compensation
Preferred Stock
We have authorized 5.0 million shares of preferred stock, par value $0.0001, none of which is issued and outstanding.

Common Stock
Each share of common stock has the right to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Board of Directors, subject to the prior rights of holders of all classes of stock outstanding having priority rights as to dividends. No dividends have been declared or paid as of December 31, 2023.

Public Offering
In March 2021, we closed a follow-on public offering in which we issued and sold approximately 2.5 million shares of common stock (including approximately 0.3 million shares sold pursuant to the full exercise of the underwriters'
option to purchase additional shares) at an offering price of $34.00 per share, resulting in aggregate net proceeds to us of approximately $82.4 million after deducting underwriting discounts, commissions and offering costs.

Common Stock Repurchase Plan
On November 14, 2019, our Board of Directors authorized the repurchase of up to $10.0 million of our outstanding shares of common stock. As of December 31, 2023, no repurchases had been executed under the program.

Equity Incentive Plan
As of December 31, 2023, there were approximately 1.7 million shares available for issuance under our equity incentive plan. Common stock issued for awards will come from newly issued shares.

Restricted Stock Awards and Units
Restricted stock award (RSA) and restricted stock unit (RSU) activity under our equity incentive plan was as follows (in thousands, except weighted-average grant date fair values):
Number of Restricted Stock AwardsWeighted-Average Grant Date Fair Value
RSAs at December 31, 2022332 $28.24 
Awards granted(32)33.66 
Awards vested(167)25.46 
RSAs at December 31, 2023133 30.44 

Number of Restricted Stock UnitsWeighted-Average Grant Date Fair Value
RSUs at December 31, 20222,784 $17.63 
Awards granted1,639 10.79 
Awards vested(1,268)17.96 
Awards forfeited(338)19.52 
RSUs at December 31, 20232,817 13.27 

The total fair value of RSAs and RSUs vested during the year ended December 31, 2023 was $4.3 million and $22.8 million, respectively. Awards outstanding as of December 31, 2023 include 0.8 million performance-based awards that will vest upon meeting certain performance criteria. Approximately 0.5 million total performance-based awards were granted in 2023. The awards vest based on a market metric called Total Shareholder Return ("TSR") for the performance period of three years relative to the TSR of companies in the Russell 2000 Index had a weighted average grant-date fair value of $14.21 per share using a Monte Carlo simulation pricing model.

Stock Options
The following table summarizes our stock option activity during the year ended December 31, 2023 (in thousands, except weighted-average exercise prices):
 Number of OptionsWeighted-Average Exercise PriceWeighted-Average Remaining Contractual Term (Years)Aggregate Intrinsic Value
Outstanding, December 31, 20221,827 $1.293.4$16,156
Options exercised(428)$1.50
Options canceled(1)$1.26
Outstanding, December 31, 20231,398 $1.242.5$17,142
Options exercisable at December 31, 20231,398 $1.242.5$17,142
Options vested as of December 31, 2023, and expected to vest after December 31, 20231,398 $1.242.5$17,142
Total intrinsic value of options exercised for the years ended December 31, 2023, 2022 and 2021 was $4.2 million, $7.7 million and $27.1 million, respectively. We received proceeds of $0.6 million, $1.2 million and $1.1 million from the exercise of options for each of the years ended December 31, 2023, 2022 and 2021, respectively.

Employee Stock Purchase Plan
Information related to activity under our Employee Stock Purchase Plan (ESPP) was as follows:
 Year Ended
December 31, 2023
Shares issued (in thousands)263 
Weighted-average per share purchase price$9.40 
Weighted-average per share discount from the fair value of our common stock on date of issuance$1.66 

As of December 31, 2023, there were 4.1 million shares available for grant under the ESPP.

Stock-Based Compensation
Total stock-based compensation expense was included in our Consolidated Statements of Operations as follows (in thousands):
Year Ended December 31,
202320222021
Cost of revenues$2,406 $2,677 $2,505 
Research and development9,866 11,675 13,433 
Sales, general and administrative13,560 12,405 21,782 
$25,832 $26,757 $37,720 

Unrecognized Compensation Costs
As of December 31, 2023, total unrecognized stock-based compensation was $30.9 million, which will be recognized over an average expected recognition period of 1.8 years.
v3.24.0.1
401(k) Plan
 12 Months Ended
Dec. 31, 2023
Retirement Benefits [Abstract]  
401(k) Plan 401(k) Plan
We have a 401(k) Profit Sharing Plan and Trust (the Plan). Participation in the Plan is voluntary and is available to all employees. We may make discretionary matching or qualified non-elective contributions to the Plan. The match is recorded within the Cost of revenue and Operating expenses in the Consolidated Statements of Operations and was as follows (in thousands):
Year Ended December 31,
202320222021
401(k) match$1,268 $1,323 $1,064 
v3.24.0.1
Segment Information
 12 Months Ended
Dec. 31, 2023
Segment Reporting [Abstract]  
Segment Information Segment Information
We operate in two reportable segments consisting of the Laser Products segment and the Advanced Development segment. The following table summarizes the operating results by reportable segment for the periods presented (dollars in thousands):
Year Ended December 31, 2023
Laser ProductsAdvanced DevelopmentCorporate and OtherTotals
Revenue$156,666 $53,255 $— $209,921 
Gross profit$44,891 $3,628 $(2,406)$46,113 
Gross margin28.7 %6.8 %NM*22.0 %
Year Ended December 31, 2022
Laser ProductsAdvanced DevelopmentCorporate and OtherTotals
Revenue$192,658 $49,400 $— $242,058 
Gross profit$50,063 $3,435 $(2,677)$50,821 
Gross margin26.0 %7.0 %NM*21.0 %
Year Ended December 31, 2021
Laser ProductsAdvanced DevelopmentCorporate and OtherTotals
Revenue$206,195 $63,951 $— $270,146 
Gross profit$75,833 $3,979 $(2,505)$77,307 
Gross margin36.8 %6.2 %NM*28.6 %
*NM = not meaningful
Corporate and Other is unallocated expenses related to stock-based compensation.

The geographic location of our long-lived assets, net, based on location of the assets, was as follows (in thousands):

As of December 31,
20232022
North America $73,070 $82,293 
China 8,916 10,177 
Rest of World4,263 6,007 
$86,249 $98,477 
v3.24.0.1
Net Loss per Share
 12 Months Ended
Dec. 31, 2023
Earnings Per Share [Abstract]  
Net Loss per Share Net Loss per Share
Basic and diluted net loss and the number of shares used for basic and diluted net loss calculations were the same for all periods presented because we were in a loss position.

The following potentially dilutive securities were not included in the calculation of diluted shares as the effect would have been anti‑dilutive (in thousands):

Year Ended December 31,
 202320222021
Restricted stock units and awards933 970 2,459 
Common stock options1,448 1,788 2,635 
 2,381 2,758 5,094 
v3.24.0.1
Pay vs Performance Disclosure - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Pay vs Performance Disclosure      
Net Income (Loss) $ (41,670) $ (54,579) $ (29,669)
v3.24.0.1
Insider Trading Arrangements
 3 Months Ended 12 Months Ended
Dec. 31, 2023
shares
Dec. 31, 2023
shares
Trading Arrangements, by Individual    
Non-Rule 10b5-1 Arrangement Adopted false  
Rule 10b5-1 Arrangement Terminated false  
Non-Rule 10b5-1 Arrangement Terminated false  
Joseph Corso [Member]    
Trading Arrangements, by Individual    
Material Terms of Trading Arrangement  
On December 15, 2023, Joseph Corso, our chief financial officer, adopted a Rule 10b5-1 trading arrangement providing for the sale from time to time of an aggregate of up to 76,199 shares of our common stock. The trading arrangement is intended to satisfy the affirmative defense in Rule 10b5-1(c). The duration of the trading arrangement is until March 18, 2025, or earlier if all transactions under the trading arrangement are completed.
Name Joseph Corso  
Title chief financial officer  
Rule 10b5-1 Arrangement Adopted true  
Adoption Date December 15, 2023  
Arrangement Duration 459 days  
Aggregate Available 76,199 76,199
v3.24.0.1
Basis of Presentation and Significant Accounting Policies (Policies)
 12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]  
Basis of Presentation
Basis of Presentation
The accompanying consolidated financial statements include the accounts of nLIGHT, Inc. and our wholly owned subsidiaries Arbor Photonics, LLC, nLIGHT Cayman Ltd., nLIGHT Laser Technology (Shanghai) Co. Ltd, nLIGHT Oy (Finland), nLIGHT Korea Inc., nLIGHT GmbH, nLIGHT DEFENSE Systems Inc. (fka Nutronics, Inc.), and nLIGHT Europe S.r.l. All intercompany balances have been eliminated.
Use of Estimates
Use of Estimates
The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates, including those related to inventory valuation, allowances for doubtful accounts, warranty, sales return reserves and the recoverability of long-lived assets. Management bases its estimates on historical experience and on various other assumptions. Actual results could differ from those estimates.
Revenue Recognition
Revenue Recognition
Cash and Cash Equivalents
Cash and Cash Equivalents
We consider all highly liquid investments with an original maturity of three months or less when acquired to be cash equivalents.Cash equivalents are carried at cost, which approximates fair value.
Inventory
Inventory
Inventory is stated at the lower of average cost (principally standard cost, which approximates actual cost on a first-in, first-out basis) and net realizable value. Inventory includes raw materials and components that may be specialized in nature and subject to obsolescence. On a quarterly basis, we review inventory quantities on hand in comparison to our past consumption, recent purchases, and other factors to determine what inventory quantities, if any, may not be sellable. Based on this analysis, we write down the affected inventory value for estimated excess and obsolescence charges. At the point of loss recognition, a new, lower-cost basis for that inventory is established, and subsequent changes in facts and circumstances do not result in the restoration or increase in that newly established cost basis.
Property, Plant and Equipment
Property, Plant and Equipment
Property, plant and equipment are stated at cost, net of accumulated depreciation. Improvements and replacements are capitalized. Repair and maintenance costs are expensed as incurred. Depreciation is computed using the straight‑line method over the estimated useful life of each asset, generally 2 to 12 years for property and equipment, and 30 years for buildings. Land is not depreciated.
Goodwill
Goodwill
Goodwill is recorded when the purchase price of an acquisition exceeds the fair value of the net assets acquired. Goodwill is not amortized and is tested for impairment at least annually and more frequently if material changes in events or circumstances arise. We perform an annual impairment review of goodwill in the fourth quarter of each year using either a qualitative assessment or a quantitative goodwill impairment test. If the qualitative assessment is selected and determines that the fair value of each reporting unit more likely than not exceeds its carrying value, no further assessment is necessary. If a quantitative test is determined necessary and an impairment is indicated, the impairment loss is recorded to the extent that the reporting unit’s carrying amount exceeds the reporting unit’s fair value. An impairment loss cannot exceed the total amount of goodwill allocated to the reporting unit.
Intangible Assets
Intangible Assets
Definite-lived intangible assets consist of acquisition-related development programs, developed technology, and intellectual property. The intangible assets are being amortized using the straight-line method over periods of 2 to 5 years, which reflect the pattern in which economic benefits of the assets are expected to be realized.
Restructuring Charges
Restructuring Charges
Restructuring charges in 2023 were comprised primarily of employee severance and in 2022 were comprised of employee severance and abandoned in-process capital equipment projects related to production capacity that were never placed into service.

The determination of when we accrue for employee termination benefits depends on whether the termination benefits are provided under a one-time benefit arrangement or under an on-going benefit arrangement. For restructuring charges recorded as an on-going benefit arrangement, a liability for post-employment benefits is recorded when payment is probable, the amount is reasonably estimable, and the obligation relates to rights that have vested or accumulated. For restructuring charges recorded as a one-time benefit arrangement, we recognize a liability for employee termination benefits when a plan of termination, approved by management and establishing the terms of the benefit arrangement, has been communicated to employees. The timing of the recognition of one-time employee termination benefits is dependent upon the period of time the employees are required to render service after communication. If employees are not required to render service in order to receive the termination benefits or if employees will not be retained to render service beyond the minimum legal notification period, a liability for the termination benefits is recognized at the communication date. In instances where employees will be retained to render service beyond the minimum legal notification period, the liability for employee termination benefits is measured initially at the communication date based on the fair value of the liability as of the termination date and is recognized ratably over the future service period. We continually evaluate the adequacy of the remaining liabilities under our restructuring initiatives.

We record charges related to long-lived assets to be abandoned when the assets cease to be used, and any inventory charges related to restructuring are classified as a cost of revenue.

Although we believe that these estimates accurately reflect the costs of our restructuring plans, actual results may differ, thereby requiring us to record additional provisions or reverse a portion of such provisions.
Impairment of Long-Lived Assets
Impairment of Long‑Lived Assets
Long‑lived assets, such as property, plant and equipment, and intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the asset.
Research and Development Costs
Research and Development Costs
Research and development is defined as activities aimed at developing or significantly improving a product or a process or technique whether the product or process is intended for sale or use. A process also may be used internally as a part of a manufacturing activity. Research and development costs are expensed as incurred.
Stock‑Based Compensation
Stock-Based Compensation
We recognize compensation expense for stock-based awards on a straight-line basis based on the grant-date estimated fair values and requisite service period. The fair value of stock options is measured using the Black-Scholes option pricing model, while the fair value of restricted stock units (RSU) and restricted stock awards (RSA) are measured based on the closing market price of our common stock on the date of grant. For RSUs and RSAs with performance conditions, compensation costs are also based on the probable outcome of achieving the specified performance conditions. The fair value of restricted stock awards based on certain market performance criteria is measured using the Monte Carlo simulation pricing model.
Income Taxes
Income Taxes
We account for income taxes using the asset and liability approach under which deferred income taxes are provided based upon enacted tax laws and rates applicable to the periods in which taxes become payable.
We recognize the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely to be realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs.
Translation of Foreign Currencies
Translation of Foreign Currencies
Our international subsidiaries use their local currency as their functional currency. The financial statements of the international subsidiaries are translated to their U.S. dollar equivalents at end‑of‑period currency exchange rates for assets and liabilities and at average currency exchange rates for revenues and expenses. Translation adjustments are recorded as a component of Accumulated other comprehensive loss within stockholders’ equity. Realized and unrealized foreign currency gains or losses, net are recorded in Other income, net within the Consolidated Statements of Operations.
New Accounting Pronouncements
New Accounting Pronouncements

ASU 2023-07
In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures. The amendments in this ASU are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We are currently evaluating the impact of this guidance on our consolidated financial statements.

ASU 2023-09
In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. This ASU requires enhanced jurisdictional and other disaggregated disclosures for the effective tax rate reconciliation and income taxes paid and is effective for fiscal years beginning after December 15, 2024. This ASU requires additional disclosures and, accordingly, we do not expect the adoption of ASU 2023-09 to have a material effect on our financial position, results of operations or cash flows.
Product Warranties
We provide warranties on certain products and record a liability for the estimated future costs associated with warranty claims at the time revenue is recognized. The warranty liability is based on historical experience, any specifically identified failures, and our estimate of future costs. The current portion of our product warranty liability is included in the accrued liabilities and the long-term portion is included in Other long-term liabilities in our Consolidated Balance Sheets.
v3.24.0.1
Basis of Presentation and Significant Accounting Policies (Tables)
 12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]  
Schedule of Amortization Expense Related To Demo Assets
Amortization expense related to demo assets was as follows (in thousands):

Year Ended December 31,
 202320222021
Amortization expense$1,150 $1,544 $1,979 
Schedule of Realized and Unrealized Foreign Currency Gains and Losses Realized and unrealized foreign currency gains and losses were as follows for the periods presented (in thousands):
Year Ended December 31,
 202320222021
Realized foreign currency gain$1,169 $(967)$(294)
Unrealized foreign currency loss(1,140)1,052 102 
v3.24.0.1
Revenue (Tables)
 12 Months Ended
Dec. 31, 2023
Revenue from Contract with Customer [Abstract]  
Schedule of Sales by End Market
The following tables represent a disaggregation of revenue from contracts with customers for the periods presented (in thousands):
    
Sales by End Market
Year Ended December 31,
 202320222021
Industrial$71,044 $91,098 $94,795 
Microfabrication47,483 62,769 70,412 
Aerospace and Defense91,394 88,191 104,939 
$209,921 $242,058 $270,146 
Schedule of Sales by Geography
Sales by Geography

Year Ended December 31,
 202320222021
North America$129,311 $137,454 $143,232 
China11,890 21,287 55,446 
Rest of World68,720 83,317 71,468 
$209,921 $242,058 $270,146 
Schedule of Sales by Timing of Revenue
Sales by Timing of Revenue

Year Ended December 31,
 202320222021
Point in time$155,258 $183,005 $198,838 
Over time54,663 59,053 71,308 
$209,921 $242,058 $270,146 
Schedule of Contract Assets and Liabilities
Our contract assets and liabilities were as follows (in thousands):
Balance Sheet ClassificationAs of December 31,
 20232022$ Change% Change
Contract assetsPrepaid expenses and
other current assets		$7,298 $10,377 $(3,079)(30)%
Contract liabilitiesDeferred revenues and other long-term liabilities6,368 2,455 3,913 159 %
v3.24.0.1
Concentrations of Credit and Other Risks (Tables)
 12 Months Ended
Dec. 31, 2023
Risks and Uncertainties [Abstract]  
Schedule of Concentration of Credit
The following customer accounted for 10% or more of our revenues for the periods presented:
Year Ended December 31,
202320222021
U.S. Government*18%17%22%
*Excludes sales to customers who sell our products and services exclusively to the U.S. Government
v3.24.0.1
Accounts Receivable (Tables)
 12 Months Ended
Dec. 31, 2023
Receivables [Abstract]  
Schedule of Allowance for Doubtful Accounts
Activity related to the allowance for doubtful accounts was as follows for the periods presented (in thousands):
Year Ended December 31,
202320222021
Allowance for doubtful accounts, beginning$290 $303 $367 
Provision (benefit) for losses on accounts receivable27 27 (4)
Write-offs, net(2)(40)(60)
Allowance for doubtful accounts, ending$315 $290 $303 
v3.24.0.1
Fair Value of Financial Instruments (Tables)
 12 Months Ended
Dec. 31, 2023
Fair Value Disclosures [Abstract]  
Schedule of Fair Value Hierarchy for Its Cash Equivalents
Our fair value hierarchy for our financial instruments was as follows (in thousands):
December 31, 2023
Level 1Level 2Level 3Total
Cash Equivalents:
  Money market securities $22,441 $— $— $22,441 
  Commercial paper1,995 — — 1,995 
24,436 — — 24,436 
Marketable Securities:
  U.S. treasuries59,672 — — 59,672 
Total$84,108 $— $— $84,108 
December 31, 2022
Level 1Level 2Level 3Total
Cash Equivalents:
  Money market securities$31,658 $— $— $31,658 
  Commercial paper656 — — 656 
32,314 — — 32,314 
Marketable Securities:
  U.S. treasuries50,391 — — 50,391 
Total$82,705 $— $— $82,705 
v3.24.0.1
Inventory (Tables)
 12 Months Ended
Dec. 31, 2023
Inventory Disclosure [Abstract]  
Schedule of Components of Inventory
Inventory consisted of the following (in thousands):
As of December 31,
20232022
Raw materials$23,426 $32,515 
Work in process and semi-finished goods19,640 19,056 
Finished goods9,094 16,029 
$52,160 $67,600 
v3.24.0.1
Property, Plant and Equipment (Tables)
 12 Months Ended
Dec. 31, 2023
Property, Plant and Equipment [Abstract]  
Schedule of Property and Equipment
Property, plant and equipment consisted of the following (in thousands):
Useful lifeAs of December 31,
 (years)20232022
Automobiles3$109 $110 
Computer hardware and software
3 - 5
9,145 8,712 
Manufacturing and lab equipment
2 - 7
91,050 89,230 
Office equipment and furniture
5 - 7
2,634 2,410 
Leasehold and building improvements
2 - 12
31,988 30,675 
Buildings309,392 9,392 
LandN/A3,399 3,399 
147,717 143,928 
Accumulated depreciation (95,417)(83,235)
$52,300 $60,693 
v3.24.0.1
Intangible Assets and Goodwill (Tables)
 12 Months Ended
Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]  
Schedule of Intangible Assets
The details of definite lived intangible assets were as follows (in thousands):
Estimated useful life
(in years) 		As of December 31,
 20232022
Patents
3 - 5
$6,345 $6,322 
Development programs
2 - 4
7,200 7,200 
Developed technology52,959 2,930 
16,504 16,452 
Accumulated amortization (14,852)(12,411)
$1,652 $4,041 
Schedule of Finite-lived Intangible Assets Amortization Expense
Amortization related to intangible assets was as follows (in thousands):
Year Ended December 31,
 202320222021
Amortization expense$2,410 $2,879 $3,891 
Schedule of Estimated Future Amortization Expense
Estimated amortization expense for future years is as follows (in thousands):
2024$819 
2025484 
2026349 
Thereafter— 
$1,652 
Schedule of Goodwill
The carrying amount of goodwill by segment was as follows (in thousands):
Laser ProductsAdvanced DevelopmentTotals
Balance, December 31, 2021$2,172 $10,248 $12,420 
Currency exchange rate adjustment(44)— (44)
Balance, December 31, 20222,128 10,248 12,376 
Currency exchange rate adjustment23 — 23 
Balance, December 31, 2023$2,151 $10,248 $12,399 
v3.24.0.1
Accrued Liabilities (Tables)
 12 Months Ended
Dec. 31, 2023
Payables and Accruals [Abstract]  
Schedule of Accrued Liabilities
Accrued liabilities consisted of the following (in thousands):
As of December 31,
20232022
Accrued payroll and benefits$7,898 $8,233 
Product warranty, current3,339 2,601 
Other accrued expenses1,319 1,986 
$12,556 $12,820 
v3.24.0.1
Product Warranties (Tables)
 12 Months Ended
Dec. 31, 2023
Guarantees and Product Warranties [Abstract]  
Schedule of Reconciliation of the Changes in the Aggregate Product Warranty Liability
Product warranty liability activity was as follows for the periods presented (in thousands):
Year Ended December 31,
 20232022
Product warranty liability, beginning$5,441 $5,371 
Warranty charges incurred, net(3,788)(1,490)
Provision for warranty charges, net of adjustments2,816 1,560 
Product warranty liability, ending4,469 5,441 
Less: current portion of product warranty liability(3,339)(2,601)
Non-current portion of product warranty liability$1,130 $2,840 
v3.24.0.1
Leases (Tables)
 12 Months Ended
Dec. 31, 2023
Leases [Abstract]  
Schedule of Components of Lease Expense
The components of lease expense related to operating leases were as follows (in thousands):
Year Ended December 31,
202320222021
Lease expense:
Operating lease expense$3,671 $3,865 $3,924 
Short-term lease expense472 573 525 
Variable and other lease expense1,020 872 741 
$5,163 $5,310 $5,190 
Schedule of Future Minimum Payments Under Non-cancelable Lease Obligations
Future minimum payments under our non-cancelable lease obligations were as follows as of December 31, 2023 (in thousands):
2024$3,687 
20252,408 
20261,741 
20271,688 
20281,413 
Thereafter5,410 
Total minimum lease payments16,347 
Less: interest(2,188)
Present value of net minimum lease payments14,159 
Less: current portion of lease liabilities(3,181)
Total long-term lease liabilities$10,978 
v3.24.0.1
Restructuring (Tables)
 12 Months Ended
Dec. 31, 2023
Restructuring and Related Activities [Abstract]  
Schedule of Restructuring Activity Restructuring charges in 2023 and 2022 were as follows (in thousands):
Year Ended December 31,
20232022
Employee termination costs$737 $1,271 
Write-down of long-lived assets— 2,566 
Other79 55 
Total restructuring charges$817 $3,892 
Restructuring accruals and payments in 2023 and 2022 were as follows (in thousands):
Accrued restructuring charges at December 31, 2021$— 
Restructuring charges3,892
Cash payments(1,134)
Non-cash settlements(2,566)
Accrual at December 31, 2022192 
Restructuring charges817
Cash payments(1,009)
Accrual at December 31, 2023$— 
v3.24.0.1
Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2023
Income Tax Disclosure [Abstract]  
Schedule of Net Income (Loss) Before Income Tax Expense
Loss before income taxes was as follows (in thousands):
 Year Ended December 31,
202320222021
Domestic$(46,602)$(50,611)$(33,940)
Foreign3,954 (3,624)3,896 
Loss before income taxes$(42,648)$(54,235)$(30,044)
Schedule of Income Tax Provision
The income tax provision (benefit) was as follows (in thousands):
Year Ended December 31,
 202320222021
Current tax expense (benefit):
State$53 $73 $70 
Foreign(985)264 (458)
Current tax expense (benefit)(932)337 (388)
Deferred tax expense (benefit):
Foreign(46)7 13 
Deferred tax expense (benefit)(46)7 13 
Income tax expense (benefit)$(978)$344 $(375)
Schedule of Effective Income Tax Rate Reconciliation
The income tax provision (benefit) differs from the amount computed by applying the statutory federal income tax rate of 21% to the loss before income taxes as a result of the following differences (in thousands):

Year Ended December 31,
 202320222021
Tax computed at federal statutory rate$(8,956)$(11,436)$(6,309)
State tax, net of federal tax benefit(800)(842)(407)
Permanent items(364)(522)(333)
Stock-based compensation1,923 4,005 (3,307)
Foreign dividends and unremitted earnings104 (231)78 
Foreign rate differential146 (360)29 
Rate change due to tax reform— — 918 
Federal credits(988)(445)(993)
Tax contingencies, net of reversals(1,177)256 838 
Return to provision(429)(523)(1,123)
Expiration of net operating loss carryforwards1,810 — — 
Other49 (324)(305)
Valuation allowance7,704 10,766 10,539 
Income tax expense (benefit)$(978)$344 $(375)
Schedule of Deferred Tax Assets and Deferred Tax Liabilities
The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are as follows (in thousands):
Year Ended December 31,
 202320222021
Deferred tax assets:
Net operating loss carryforwards$39,714 $39,998 $35,585 
Research and alternative minimum tax credits7,822 6,658 6,535 
Accrued expenses and other4,365 4,999 7,020 
Lease liabilities2,854 3,270 3,525 
Inventory3,283 3,305 5,852 
Property and equipment387 293 — 
Intangible assets16,612 9,184 — 
Total gross deferred tax assets75,037 67,707 58,517 
Less: valuation allowance(72,461)(64,796)(54,239)
Total deferred tax assets2,576 2,911 4,278 
Deferred tax liabilities:
Property and equipment— — (87)
Intangible assets— — (767)
Right-of-use assets(2,487)(2,869)(3,378)
Total deferred tax liabilities(2,487)(2,869)(4,232)
Net deferred tax assets$89 $42 $46 
Schedule of Reconciliation of Changes In Unrecognized Tax Benefit
The following table presents a reconciliation of the changes in the unrecognized tax benefit (in thousands):

Balance at December 31, 2020$7,859 
Additions based on tax positions related to the current year661 
Additions for tax positions of prior years53 
Reductions as a result of a lapse of applicable statute of limitations(250)
Other112 
Balance at December 31, 20218,435 
Additions based on tax positions related to the current year822 
Reductions for tax positions of prior years(53)
Reductions as a result of a lapse of applicable statute of limitations(183)
Other(437)
Balance at December 31, 20228,584 
Additions based on tax positions related to the current year416 
Reductions for tax positions of prior years(70)
Reductions as a result of a lapse of applicable statute of limitations(371)
Other(84)
Balance at December 31, 2023$8,475 
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2023
Equity [Abstract]  
Schedule of Restricted Stock Awards and Units
Restricted stock award (RSA) and restricted stock unit (RSU) activity under our equity incentive plan was as follows (in thousands, except weighted-average grant date fair values):
Number of Restricted Stock AwardsWeighted-Average Grant Date Fair Value
RSAs at December 31, 2022332 $28.24 
Awards granted(32)33.66 
Awards vested(167)25.46 
RSAs at December 31, 2023133 30.44 

Number of Restricted Stock UnitsWeighted-Average Grant Date Fair Value
RSUs at December 31, 20222,784 $17.63 
Awards granted1,639 10.79 
Awards vested(1,268)17.96 
Awards forfeited(338)19.52 
RSUs at December 31, 20232,817 13.27 
Schedule of Stock Option Activity
The following table summarizes our stock option activity during the year ended December 31, 2023 (in thousands, except weighted-average exercise prices):
 Number of OptionsWeighted-Average Exercise PriceWeighted-Average Remaining Contractual Term (Years)Aggregate Intrinsic Value
Outstanding, December 31, 20221,827 $1.293.4$16,156
Options exercised(428)$1.50
Options canceled(1)$1.26
Outstanding, December 31, 20231,398 $1.242.5$17,142
Options exercisable at December 31, 20231,398 $1.242.5$17,142
Options vested as of December 31, 2023, and expected to vest after December 31, 20231,398 $1.242.5$17,142
Schedule of Employee Stock Purchase Plan
Information related to activity under our Employee Stock Purchase Plan (ESPP) was as follows:
 Year Ended
December 31, 2023
Shares issued (in thousands)263 
Weighted-average per share purchase price$9.40 
Weighted-average per share discount from the fair value of our common stock on date of issuance$1.66 
Schedule of Stock-based Compensation Expense
Total stock-based compensation expense was included in our Consolidated Statements of Operations as follows (in thousands):
Year Ended December 31,
202320222021
Cost of revenues$2,406 $2,677 $2,505 
Research and development9,866 11,675 13,433 
Sales, general and administrative13,560 12,405 21,782 
$25,832 $26,757 $37,720 
v3.24.0.1
401(k) Plan (Tables)
 12 Months Ended
Dec. 31, 2023
Retirement Benefits [Abstract]  
Schedule of 401(k) Match The match is recorded within the Cost of revenue and Operating expenses in the Consolidated Statements of Operations and was as follows (in thousands):
Year Ended December 31,
202320222021
401(k) match$1,268 $1,323 $1,064 
v3.24.0.1
Segment Information (Tables)
 12 Months Ended
Dec. 31, 2023
Segment Reporting [Abstract]  
Schedule of Operating Results by Reportable Segment The following table summarizes the operating results by reportable segment for the periods presented (dollars in thousands):
Year Ended December 31, 2023
Laser ProductsAdvanced DevelopmentCorporate and OtherTotals
Revenue$156,666 $53,255 $— $209,921 
Gross profit$44,891 $3,628 $(2,406)$46,113 
Gross margin28.7 %6.8 %NM*22.0 %
Year Ended December 31, 2022
Laser ProductsAdvanced DevelopmentCorporate and OtherTotals
Revenue$192,658 $49,400 $— $242,058 
Gross profit$50,063 $3,435 $(2,677)$50,821 
Gross margin26.0 %7.0 %NM*21.0 %
Year Ended December 31, 2021
Laser ProductsAdvanced DevelopmentCorporate and OtherTotals
Revenue$206,195 $63,951 $— $270,146 
Gross profit$75,833 $3,979 $(2,505)$77,307 
Gross margin36.8 %6.2 %NM*28.6 %
*NM = not meaningful
Schedule of Revenue and Long-lived Assets by Geographical Areas
The geographic location of our long-lived assets, net, based on location of the assets, was as follows (in thousands):

As of December 31,
20232022
North America $73,070 $82,293 
China 8,916 10,177 
Rest of World4,263 6,007 
$86,249 $98,477 
v3.24.0.1
Net Loss per Share (Tables)
 12 Months Ended
Dec. 31, 2023
Earnings Per Share [Abstract]  
Schedule of Potentially Dilutive Shares Not Included in Calculation of Diluted Shares
The following potentially dilutive securities were not included in the calculation of diluted shares as the effect would have been anti‑dilutive (in thousands):

Year Ended December 31,
 202320222021
Restricted stock units and awards933 970 2,459 
Common stock options1,448 1,788 2,635 
 2,381 2,758 5,094 
v3.24.0.1
Basis of Presentation and Significant Accounting Policies - Narrative (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Cash and cash equivalents, fair value disclosure $ 24,436,000 $ 32,314,000  
Goodwill impairment $ 0 0 $ 0
Useful life of demonstration assets 2 years    
Long-lived assets impairment $ 0 $ 0 $ 0
Buildings      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Property and equipment useful life 30 years    
Minimum      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Estimated useful life (in years) 2 years    
Minimum | Property And Equipment      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Property and equipment useful life 2 years    
Maximum      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Estimated useful life (in years) 5 years    
Maximum | Property And Equipment      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Property and equipment useful life 12 years    
v3.24.0.1
Basis of Presentation and Significant Accounting Policies - Amortization Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Accounting Policies [Abstract]      
Amortization expense $ 1,150 $ 1,544 $ 1,979
v3.24.0.1
Basis of Presentation and Significant Accounting Policies - Realized and Unrealized Foreign Currency Gains and Losses (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Accounting Policies [Abstract]      
Realized foreign currency gain $ 1,169 $ (967) $ (294)
Unrealized foreign currency loss $ (1,140) $ 1,052 $ 102
v3.24.0.1
Revenue - Narrative (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]    
Revenue recognized, previously included in customer advances and deferred revenue $ 1.5 $ 1.6
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]    
Performance obligation $ 30.0  
Performance obligation, scheduled delivery, period 1 year  
Performance obligation, percentage 80.00%  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01    
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]    
Performance obligation, scheduled delivery, period 2 years  
v3.24.0.1
Revenue - Disaggregation of Revenue (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Disaggregation of Revenue [Line Items]      
Total revenue $ 209,921 $ 242,058 $ 270,146
Point in time      
Disaggregation of Revenue [Line Items]      
Total revenue 155,258 183,005 198,838
Over time      
Disaggregation of Revenue [Line Items]      
Total revenue 54,663 59,053 71,308
North America      
Disaggregation of Revenue [Line Items]      
Total revenue 129,311 137,454 143,232
China      
Disaggregation of Revenue [Line Items]      
Total revenue 11,890 21,287 55,446
Rest of World      
Disaggregation of Revenue [Line Items]      
Total revenue 68,720 83,317 71,468
Industrial      
Disaggregation of Revenue [Line Items]      
Total revenue 71,044 91,098 94,795
Microfabrication      
Disaggregation of Revenue [Line Items]      
Total revenue 47,483 62,769 70,412
Aerospace and Defense      
Disaggregation of Revenue [Line Items]      
Total revenue $ 91,394 $ 88,191 $ 104,939
v3.24.0.1
Revenue - Contract Assets and Liabilities (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Revenue from Contract with Customer [Abstract]    
Contract assets $ 7,298 $ 10,377
Contract liabilities 6,368 $ 2,455
Contract assets, $ Change $ (3,079)  
Contract Assets, % Change (30.00%)  
Contract liabilities, $ Change $ 3,913  
Contract liabilities, % Change 159.00%  
v3.24.0.1
Concentrations of Credit and Other Risks (Details) - Customer Concentration Risk
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Sales Revenue | U.S. Government      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 18.00% 17.00% 22.00%
Accounts Receivable | Two customers      
Concentration Risk [Line Items]      
Concentration risk (as a percent) 24.00% 29.00%  
v3.24.0.1
Accounts Receivable (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Accounts Receivable, Allowance for Credit Loss [Roll Forward]      
Allowance for doubtful accounts, beginning $ 290 $ 303 $ 367
Provision (benefit) for losses on accounts receivable 27 27 (4)
Write-offs, net (2) (40) (60)
Allowance for doubtful accounts, ending $ 315 $ 290 $ 303
v3.24.0.1
Marketable Securities (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Investments, All Other Investments [Abstract]      
Realized gains on available-for-sale securities $ 2,400 $ 200  
Unrealized gains on available-for-sale securities $ 520 $ 394 $ 0
v3.24.0.1
Fair Value of Financial Instruments (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: $ 24,436 $ 32,314
Total 84,108 82,705
Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 24,436 32,314
Total 84,108 82,705
Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 0 0
Total 0 0
Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 0 0
Total 0 0
Money market securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 22,441 31,658
Money market securities | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 22,441 31,658
Money market securities | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 0 0
Money market securities | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 0 0
Commercial paper    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 1,995 656
Commercial paper | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 1,995 656
Commercial paper | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 0 0
Commercial paper | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash Equivalents: 0 0
U.S. treasuries    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Marketable Securities: 59,672 50,391
U.S. treasuries | Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Marketable Securities: 59,672 50,391
U.S. treasuries | Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Marketable Securities: 0 0
U.S. treasuries | Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Marketable Securities: $ 0 $ 0
v3.24.0.1
Inventory (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Inventory Disclosure [Abstract]    
Raw materials $ 23,426 $ 32,515
Work in process and semi-finished goods 19,640 19,056
Finished goods 9,094 16,029
Inventory $ 52,160 $ 67,600
v3.24.0.1
Property, Plant and Equipment (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 147,717 $ 143,928
Accumulated depreciation (95,417) (83,235)
Property and equipment, net $ 52,300 60,693
Automobiles    
Property, Plant and Equipment [Line Items]    
Useful life 3 years  
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 109 110
Computer hardware and software    
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 9,145 8,712
Computer hardware and software | Minimum    
Property, Plant and Equipment [Line Items]    
Useful life 3 years  
Computer hardware and software | Maximum    
Property, Plant and Equipment [Line Items]    
Useful life 5 years  
Manufacturing and lab equipment    
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 91,050 89,230
Manufacturing and lab equipment | Minimum    
Property, Plant and Equipment [Line Items]    
Useful life 2 years  
Manufacturing and lab equipment | Maximum    
Property, Plant and Equipment [Line Items]    
Useful life 7 years  
Office equipment and furniture    
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 2,634 2,410
Office equipment and furniture | Minimum    
Property, Plant and Equipment [Line Items]    
Useful life 5 years  
Office equipment and furniture | Maximum    
Property, Plant and Equipment [Line Items]    
Useful life 7 years  
Leasehold and building improvements    
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 31,988 30,675
Leasehold and building improvements | Minimum    
Property, Plant and Equipment [Line Items]    
Useful life 2 years  
Leasehold and building improvements | Maximum    
Property, Plant and Equipment [Line Items]    
Useful life 12 years  
Buildings    
Property, Plant and Equipment [Line Items]    
Useful life 30 years  
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 9,392 9,392
Land    
Property, Plant and Equipment, Net [Abstract]    
Property and equipment, gross $ 3,399 $ 3,399
v3.24.0.1
Intangible Assets and Goodwill - Intangible Assets & Finite-lived Intangible Assets Amortization Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]      
Gross carrying amount $ 16,504 $ 16,452  
Accumulated amortization (14,852) (12,411)  
Net value 1,652 4,041  
Amortization expense 2,410 2,879 $ 3,891
Patents      
Finite-Lived Intangible Assets [Line Items]      
Gross carrying amount 6,345 6,322  
Development programs      
Finite-Lived Intangible Assets [Line Items]      
Gross carrying amount $ 7,200 7,200  
Developed technology      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 5 years    
Gross carrying amount $ 2,959 $ 2,930  
Minimum      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 2 years    
Minimum | Patents      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 3 years    
Minimum | Development programs      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 2 years    
Maximum      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 5 years    
Maximum | Patents      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 5 years    
Maximum | Development programs      
Finite-Lived Intangible Assets [Line Items]      
Estimated useful life (in years) 4 years    
v3.24.0.1
Intangible Assets and Goodwill - Amortization of Intangible Assets (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]    
2024 $ 819  
2025 484  
2026 349  
Thereafter 0  
Net value $ 1,652 $ 4,041
v3.24.0.1
Intangible Assets and Goodwill - Goodwill (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Goodwill [Roll Forward]    
Beginning balance $ 12,376 $ 12,420
Currency exchange rate adjustment 23 (44)
Ending balance 12,399 12,376
Laser Products    
Goodwill [Roll Forward]    
Beginning balance 2,128 2,172
Currency exchange rate adjustment 23 (44)
Ending balance 2,151 2,128
Advanced Development    
Goodwill [Roll Forward]    
Beginning balance 10,248 10,248
Currency exchange rate adjustment 0 0
Ending balance $ 10,248 $ 10,248
v3.24.0.1
Accrued Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Payables and Accruals [Abstract]    
Accrued payroll and benefits $ 7,898 $ 8,233
Product warranty, current 3,339 2,601
Other accrued expenses 1,319 1,986
Total accrued liabilities $ 12,556 $ 12,820
v3.24.0.1
Product Warranties (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Movement in Standard Product Warranty Accrual [Roll Forward]    
Product warranty liability, beginning $ 5,441 $ 5,371
Warranty charges incurred, net (3,788) (1,490)
Provision for warranty charges, net of adjustments 2,816 1,560
Product warranty liability, ending 4,469 5,441
Less: current portion of product warranty liability (3,339) (2,601)
Non-current portion of product warranty liability $ 1,130 $ 2,840
v3.24.0.1
Commitments and Contingencies (Details) - Revolving Credit Facility - Line of Credit - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Line of Credit Facility [Line Items]    
Revolving line of credit, borrowing capacity $ 40,000,000  
Unused credit fee (percent) 0.20%  
Amounts outstanding under line of credit $ 0 $ 0
v3.24.0.1
Leases - Narrative (Details)
Dec. 31, 2023
Lessee, Lease, Description [Line Items]  
Weighted-average remaining lease term for operating leases (in years) 7 years
Weighted-average discount rate for operating leases (as a percent) 3.80%
Operating Leases, Facilities  
Lessee, Lease, Description [Line Items]  
Renewal lease term (in years) 15 years
Operating Leases, Facilities | Minimum  
Lessee, Lease, Description [Line Items]  
Remaining lease term (in years) 3 months 18 days
Operating Leases, Facilities | Maximum  
Lessee, Lease, Description [Line Items]  
Remaining lease term (in years) 11 years 4 months 24 days
Operating Leases, Automobiles and Equipment | Minimum  
Lessee, Lease, Description [Line Items]  
Remaining lease term (in years) 2 months 12 days
Operating Leases, Automobiles and Equipment | Maximum  
Lessee, Lease, Description [Line Items]  
Remaining lease term (in years) 4 years 9 months 18 days
v3.24.0.1
Leases - Components of Lease Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Leases [Abstract]      
Operating lease expense $ 3,671 $ 3,865 $ 3,924
Short-term lease expense 472 573 525
Variable and other lease expense 1,020 872 741
Lease expense $ 5,163 $ 5,310 $ 5,190
v3.24.0.1
Leases - Future Minimum Payments Under Non-Cancelable Operating Leases (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Leases [Abstract]    
2024 $ 3,687  
2025 2,408  
2026 1,741  
2027 1,688  
2028 1,413  
Thereafter 5,410  
Total minimum lease payments 16,347  
Less: interest (2,188)  
Present value of net minimum lease payments 14,159  
Less: current portion of lease liabilities (3,181) $ (2,758)
Total long-term lease liabilities $ 10,978 $ 12,852
v3.24.0.1
Restructuring - Schedule of Restructuring Charges (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]      
Restructuring charges $ 817 $ 3,892 $ 0
Employee termination costs      
Restructuring Cost and Reserve [Line Items]      
Restructuring charges 737 1,271  
Write-down of long-lived assets      
Restructuring Cost and Reserve [Line Items]      
Restructuring charges 0 2,566  
Other      
Restructuring Cost and Reserve [Line Items]      
Restructuring charges $ 79 $ 55  
v3.24.0.1
Restructuring - Schedule of Restructuring Accruals and Payments (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Restructuring Reserve [Roll Forward]      
Accrual, Beginning Balance $ 192 $ 0  
Restructuring charges 817 3,892 $ 0
Cash payments (1,009) (1,134)  
Non-cash settlements   (2,566)  
Accrual, Ending Balance $ 0 $ 192 $ 0
v3.24.0.1
Restructuring - Narrative (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Restructuring Cost and Reserve [Line Items]      
Restructuring $ 817 $ 3,892 $ 0
Laser Products      
Restructuring Cost and Reserve [Line Items]      
Restructuring   3,800  
Advanced Development      
Restructuring Cost and Reserve [Line Items]      
Restructuring   $ 100  
v3.24.0.1
Income Taxes - Net Income (Loss) Before Income Tax Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Income Tax Disclosure [Abstract]      
Domestic $ (46,602) $ (50,611) $ (33,940)
Foreign 3,954 (3,624) 3,896
Loss before income taxes $ (42,648) $ (54,235) $ (30,044)
v3.24.0.1
Income Taxes - Income Tax Provision (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Current tax expense (benefit):      
State $ 53 $ 73 $ 70
Foreign (985) 264 (458)
Current tax expense (benefit) (932) 337 (388)
Deferred tax expense (benefit):      
Foreign (46) 7 13
Deferred tax expense (benefit) (46) 7 13
Income tax expense (benefit) $ (978) $ 344 $ (375)
v3.24.0.1
Income Taxes - Tax Rate Reconciliation (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Income Tax Disclosure [Abstract]      
Tax computed at federal statutory rate $ (8,956) $ (11,436) $ (6,309)
State tax, net of federal tax benefit (800) (842) (407)
Permanent items (364) (522) (333)
Stock-based compensation 1,923 4,005 (3,307)
Foreign dividends and unremitted earnings 104 (231) 78
Foreign rate differential 146 (360) 29
Rate change due to tax reform 0 0 918
Federal credits (988) (445) (993)
Tax contingencies, net of reversals (1,177) 256 838
Return to provision (429) (523) (1,123)
Expiration of net operating loss carryforwards 1,810 0 0
Other 49 (324) (305)
Valuation allowance 7,704 10,766 10,539
Income tax expense (benefit) $ (978) $ 344 $ (375)
v3.24.0.1
Income Taxes - Narrative (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
USD ($)
event
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Income Tax [Line Items]        
Statutory tax rate 21.00%      
Valuation allowance, deferred tax assets, increase (decrease) $ 7,700 $ 10,600 $ 10,600  
Number of change in ownership events | event 3      
Unrecognized tax benefits $ 8,475 8,584 8,435 $ 7,859
Unrecognized tax benefits, recognized penalties and interest increase (decrease) (1,000) 300 $ (300)  
Unrecognized tax benefits, income tax penalties and interest accrued 900 2,000    
Deferred Tax Liabilities, Noncurrent        
Income Tax [Line Items]        
Unrecognized tax benefits 2,800      
Non-current Deferred Tax Assets        
Income Tax [Line Items]        
Unrecognized tax benefits 5,700 5,500    
Non-current Income Taxes Payable        
Income Tax [Line Items]        
Unrecognized tax benefits 2,800 $ 3,100    
Change in Ownership Event One        
Income Tax [Line Items]        
Tax credit carryforward, limitation 528      
Research and Development Credit        
Income Tax [Line Items]        
Tax credit carryforward 9,300      
Foreign Tax Authority        
Income Tax [Line Items]        
Operating loss carryforwards $ 14,500      
Foreign Tax Authority | China        
Income Tax [Line Items]        
Statutory tax rate 25.00%      
Foreign Tax Authority | Finland        
Income Tax [Line Items]        
Statutory tax rate 20.00%      
U.S.        
Income Tax [Line Items]        
Operating loss carryforwards $ 161,000      
State        
Income Tax [Line Items]        
Operating loss carryforwards $ 43,200      
v3.24.0.1
Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Deferred tax assets:      
Net operating loss carryforwards $ 39,714 $ 39,998 $ 35,585
Research and alternative minimum tax credits 7,822 6,658 6,535
Accrued expenses and other 4,365 4,999 7,020
Lease liabilities 2,854 3,270 3,525
Inventory 3,283 3,305 5,852
Property and equipment 387 293 0
Intangible assets 16,612 9,184 0
Total gross deferred tax assets 75,037 67,707 58,517
Less: valuation allowance (72,461) (64,796) (54,239)
Total deferred tax assets 2,576 2,911 4,278
Deferred tax liabilities:      
Property and equipment 0 0 (87)
Intangible assets 0 0 (767)
Right-of-use assets (2,487) (2,869) (3,378)
Total deferred tax liabilities (2,487) (2,869) (4,232)
Net deferred tax assets $ 89 $ 42 $ 46
v3.24.0.1
Income Taxes - Unrecognized Tax Benefit (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]      
Beginning balance $ 8,584 $ 8,435 $ 7,859
Additions based on tax positions related to the current year 416 822 661
Additions for tax positions of prior years     53
Reductions for tax positions of prior years (70) (53)  
Reductions as a result of a lapse of applicable statute of limitations (371) (183) (250)
Other (84) (437) 112
Ending balance $ 8,475 $ 8,584 $ 8,435
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation - Narrative (Details)
 1 Months Ended 12 Months Ended
Mar. 31, 2021
USD ($)
$ / shares
shares
Dec. 31, 2023
USD ($)
vote
$ / shares
shares
Dec. 31, 2022
USD ($)
shares
Dec. 31, 2021
USD ($)
Nov. 14, 2019
USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Preferred stock, shares authorized (in shares)   5,000,000      
Preferred stock, par value (in dollars per share) | $ / shares   $ 0.0001      
Preferred stock, shares outstanding (in shares)   0      
Preferred stock, shares issued (in shares)   0      
Number of votes each share of common stock has rights to (vote) | vote   1      
Dividends | $   $ 0      
Common stock repurchase plan, authorized | $         $ 10,000,000
Number of shares repurchased (in shares)   0      
Issuance of common stock (in shares)   1,700,000      
Intrinsic value of options exercised | $   $ 4,200,000 $ 7,700,000 $ 27,100,000  
Proceeds from the exercise of options | $   640,000 $ 1,197,000 $ 1,145,000  
Unrecognized expense | $   $ 30,900,000      
Period for recognition (in years)   1 year 9 months 18 days      
Restricted Stock Awards (RSAs)          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vested, fair value | $   $ 4,300,000      
Awards outstanding (in shares)   133,000 332,000    
Granted (in shares)   32,000      
Awards granted (in dollars per share) | $ / shares   $ 33.66      
Restricted Stock Units (RSUs)          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Vested, fair value | $   $ 22,800,000      
Awards outstanding (in shares)   2,817,000 2,784,000    
Granted (in shares)   1,639,000      
Awards granted (in dollars per share) | $ / shares   $ 10.79      
Performance-based Awards          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Awards outstanding (in shares)   800,000      
Granted (in shares)   500,000      
Vesting period   3 years      
Awards granted (in dollars per share) | $ / shares   $ 14.21      
Employee stock purchase plan          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Shares available for grant (in shares)   4,100,000      
Follow-on Public Offering          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares issued (in shares) 2,500,000        
Initial price per share in IPO (in USD per share) | $ / shares $ 34.00        
Net proceeds received from IPO | $ $ 82,400,000        
Underwriters Option to Purchase          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares issued (in shares) 300,000        
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation - Schedule of Restricted Stock Unit Activity (Details)
shares in Thousands
 12 Months Ended
Dec. 31, 2023
$ / shares
shares
Restricted Stock Awards (RSAs)  
Number of Restricted Stock Awards and Units (Thousands)  
Balance, beginning (in shares) | shares 332
Awards granted (in shares) | shares (32)
Awards vested (in shares) | shares (167)
Balance, ending (in shares) | shares 133
Weighted-Average Grant Date Fair Value  
Balance, beginning (in dollars per share) | $ / shares $ 28.24
Awards granted (in dollars per share) | $ / shares 33.66
Awards vested (in dollars per share) | $ / shares 25.46
Balance, ending (in dollars per share) | $ / shares $ 30.44
Restricted Stock Units  
Number of Restricted Stock Awards and Units (Thousands)  
Balance, beginning (in shares) | shares 2,784
Awards granted (in shares) | shares (1,639)
Awards vested (in shares) | shares (1,268)
Awards forfeited (in shares) | shares (338)
Balance, ending (in shares) | shares 2,817
Weighted-Average Grant Date Fair Value  
Balance, beginning (in dollars per share) | $ / shares $ 17.63
Awards granted (in dollars per share) | $ / shares 10.79
Awards vested (in dollars per share) | $ / shares 17.96
Awards forfeited (in dollars per share) | $ / shares 19.52
Balance, ending (in dollars per share) | $ / shares $ 13.27
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation - Schedule of Stock Option Activity (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Number of Options    
Outstanding, beginning of period (in shares) 1,827  
Options exercised (in shares) (428)  
Options canceled (in shares) (1)  
Outstanding, end of period (in shares) 1,398 1,827
Weighted-Average Exercise Price    
Outstanding, beginning of period (in dollars per share) $ 1.29  
Options exercised (in dollars per share) 1.50  
Options canceled (in dollars per share) 1.26  
Outstanding, end of period (in dollars per share) $ 1.24 $ 1.29
Outstanding, Weighted average remaining contractual term (in years) 2 years 6 months 3 years 4 months 24 days
Outstanding, Aggregate intrinsic value $ 17,142 $ 16,156
Options exercisable at end of period    
Options exercisable (in shares) 1,398  
Weighted average exercise price (in dollars per share) $ 1.24  
Weighted-Average Remaining Contractual Term 2 years 6 months  
Aggregate Intrinsic Value $ 17,142  
Options vested as of end of period and expected to vest after end of period    
Options vested and expected to vest (in shares) 1,398  
Weighted average exercise price (in dollars per share) $ 1.24  
Weighted-Average Remaining Contractual Term 2 years 6 months  
Aggregate Intrinsic Value $ 17,142  
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation - Employee Stock Purchase Program (Details)
shares in Thousands
 12 Months Ended
Dec. 31, 2023
$ / shares
shares
Equity [Abstract]  
Shares issued (in shares) | shares 263
Weighted average per share purchase price (in dollars per share) $ 9.40
Weighted average per share discount from the fair value of our common stock on date of issuance (in dollars per share) $ 1.66
v3.24.0.1
Stockholders' Equity and Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]      
Stock-based compensation expense $ 25,832 $ 26,757 $ 37,720
Cost of revenues      
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]      
Stock-based compensation expense 2,406 2,677 2,505
Research and development      
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]      
Stock-based compensation expense 9,866 11,675 13,433
Sales, general and administrative      
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]      
Stock-based compensation expense $ 13,560 $ 12,405 $ 21,782
v3.24.0.1
401(k) Plan (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Retirement Benefits [Abstract]      
401(k) match $ 1,268 $ 1,323 $ 1,064
v3.24.0.1
Segment Information - Narrative (Details)
 12 Months Ended
Dec. 31, 2023
segment
Segment Reporting [Abstract]  
Number of reportable segments 2
v3.24.0.1
Segment Information - Operating Results (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Segment Reporting Information [Line Items]      
Revenue $ 209,921 $ 242,058 $ 270,146
Gross profit $ 46,113 $ 50,821 $ 77,307
Gross margin 22.00% 21.00% 28.60%
Operating Segments | Laser Products      
Segment Reporting Information [Line Items]      
Revenue $ 156,666 $ 192,658 $ 206,195
Gross profit $ 44,891 $ 50,063 $ 75,833
Gross margin 28.70% 26.00% 36.80%
Operating Segments | Advanced Development      
Segment Reporting Information [Line Items]      
Revenue $ 53,255 $ 49,400 $ 63,951
Gross profit $ 3,628 $ 3,435 $ 3,979
Gross margin 6.80% 7.00% 6.20%
Corporate and Other      
Segment Reporting Information [Line Items]      
Revenue $ 0 $ 0 $ 0
Gross profit $ (2,406) $ (2,677) $ (2,505)
v3.24.0.1
Segment Information - Geographic Locations (Details) - USD ($)
$ in Thousands
Dec. 31, 2023
Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]    
Long-lived assets $ 86,249 $ 98,477
North America    
Revenues from External Customers and Long-Lived Assets [Line Items]    
Long-lived assets 73,070 82,293
China    
Revenues from External Customers and Long-Lived Assets [Line Items]    
Long-lived assets 8,916 10,177
Rest of World    
Revenues from External Customers and Long-Lived Assets [Line Items]    
Long-lived assets $ 4,263 $ 6,007
v3.24.0.1
Net Loss per Share (Details) - shares
shares in Thousands
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]      
Antidilutive securities (in shares) 2,381 2,758 5,094
Restricted stock units and awards      
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]      
Antidilutive securities (in shares) 933 970 2,459
Common stock options      
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]      
Antidilutive securities (in shares) 1,448 1,788 2,635