<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019cdec2-903d-75d7-a996-351fa5f614e0,g:603ca5b7-3020-4c1b-9c27-6efca3c9539d-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://xbrl.sec.gov/ecd/role/PvpDisclosure" xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#PvpDisclosure"/>
  <link:presentationLink xlink:role="http://xbrl.sec.gov/ecd/role/PvpDisclosure" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ecd_PayVsPerformanceDisclosureLineItems" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_PayVsPerformanceDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_lasr_AdjustmentToCompensationAmountEquityAwards" xlink:href="lasr-20260424.xsd#lasr_AdjustmentToCompensationAmountEquityAwards"/>
    <link:presentationArc order="32" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_ecd_PayVsPerformanceDisclosureLineItems" xlink:to="loc_lasr_AdjustmentToCompensationAmountEquityAwards" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/label"/>
    <link:loc xlink:type="locator" xlink:label="loc_ecd_AllAdjToCompMember" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#ecd_AllAdjToCompMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_lasr_GrantDateFairValueOfEquityAwardsGrantedInCoveredYearMember" xlink:href="lasr-20260424.xsd#lasr_GrantDateFairValueOfEquityAwardsGrantedInCoveredYearMember"/>
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_ecd_AllAdjToCompMember" xlink:to="loc_lasr_GrantDateFairValueOfEquityAwardsGrantedInCoveredYearMember" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/label"/>
  </link:presentationLink>
</link:linkbase>