1.1 Research Scope 1.2 Market Segmentation 1.3 Research Objectives 1.4 Research Methodology 1.4.1 Research Process 1.4.2 Data Triangulation 1.4.3 Research Approach 1.4.4 Base Year 1.5 Coronavirus Disease 2019 (Covid-19) Impact Will Have a Severe Impact on Global Growth 1.5.1 Covid-19 Impact: Global GDP Growth, 2019, 2020 and 2021 Projections 1.5.2 Covid-19 Impact: Commodity Prices Indices 1.5.3 Covid-19 Impact: Global Major Government Policy 1.6 The Covid-19 Impact on Diffractive Elements Industry 1.7 COVID-19 Impact: Diffractive Elements Market Trends 2 Global Diffractive Elements Quarterly Market Size Analysis 2.1 Diffractive Elements Business Impact Assessment - COVID-19 2.1.1 Global Diffractive Elements Market Size, Pre-COVID-19 and Post- COVID-19 Comparison, 2015-2026 2.1.2 Global Diffractive Elements Price, Pre-COVID-19 and Post- COVID-19 Comparison, 2015-2026 2.2 Global Diffractive Elements Quarterly Market Size 2020-2021 2.3 COVID-19-Driven Market Dynamics and Factor Analysis 2.3.1 Drivers 2.3.2 Restraints 2.3.3 Opportunities 2.3.4 Challenges 3 Quarterly Competitive Assessment, 2020 3.1 Global Diffractive Elements Quarterly Market Size by Manufacturers, 2019 VS 2020 3.2 Global Diffractive Elements Factory Price by Manufacturers 3.3 Location of Key Manufacturers Diffractive Elements Manufacturing Factories and Area Served 3.4 Date of Key Manufacturers Enter into Diffractive Elements Market 3.5 Key Manufacturers Diffractive Elements Product Offered 3.6 Mergers & Acquisitions, Expansion Plans 4 Impact of Covid-19 on Diffractive Elements Segments, By Type 4.1 Introduction 1.4.1 Beam Shaping/Top-Hat 1.4.2 Beam Splitting 1.4.3 Beam Foci 4.2 By Type, Global Diffractive Elements Market Size, 2019-2021 4.2.1 By Type, Global Diffractive Elements Market Size by Type, 2020-2021 4.2.2 By Type, Global Diffractive Elements Price, 2020-2021 5 Impact of Covid-19 on Diffractive Elements Segments, By Application 5.1 Overview 5.5.1 Laser Material Processing 5.5.2 Medical 5.5.3 Other 5.2 By Application, Global Diffractive Elements Market Size, 2019-2021 5.2.1 By Application, Global Diffractive Elements Market Size by Application, 2019-2021 5.2.2 By Application, Global Diffractive Elements Price, 2020-2021 6 Geographic Analysis 6.1 Introduction 6.2 North America 6.2.1 Macroeconomic Indicators of US 6.2.2 US 6.2.3 Canada 6.3 Europe 6.3.1 Macroeconomic Indicators of Europe 6.3.2 Germany 6.3.3 France 6.3.4 UK 6.3.5 Italy 6.4 Asia-Pacific 6.4.1 Macroeconomic Indicators of Asia-Pacific 6.4.2 China 6.4.3 Japan 6.4.4 South Korea 6.4.5 India 6.4.6 ASEAN 6.5 Rest of World 6.5.1 Latin America 6.5.2 Middle East and Africa 7 Company Profiles 7.1 Jenoptik 7.1.1 Jenoptik Business Overview 7.1.2 Jenoptik Diffractive Elements Quarterly Production and Revenue, 2020 7.1.3 Jenoptik Diffractive Elements Product Introduction 7.1.4 Jenoptik Response to COVID-19 and Related Developments 7.2 Holo/Or Ltd. 7.2.1 Holo/Or Ltd. Business Overview 7.2.2 Holo/Or Ltd. Diffractive Elements Quarterly Production and Revenue, 2020 7.2.3 Holo/Or Ltd. Diffractive Elements Product Introduction 7.2.4 Holo/Or Ltd. Response to COVID-19 and Related Developments 7.3 HORIBA 7.3.1 HORIBA Business Overview 7.3.2 HORIBA Diffractive Elements Quarterly Production and Revenue, 2020 7.3.3 HORIBA Diffractive Elements Product Introduction 7.3.4 HORIBA Response to COVID-19 and Related Developments 7.4 Newport Corporation 7.4.1 Newport Corporation Business Overview 7.4.2 Newport Corporation Diffractive Elements Quarterly Production and Revenue, 2020 7.4.3 Newport Corporation Diffractive Elements Product Introduction 7.4.4 Newport Corporation Response to COVID-19 and Related Developments 7.5 Zeiss 7.5.1 Zeiss Business Overview 7.5.2 Zeiss Diffractive Elements Quarterly Production and Revenue, 2020 7.5.3 Zeiss Diffractive Elements Product Introduction 7.5.4 Zeiss Response to COVID-19 and Related Developments 7.6 Shimadzu Corporation 7.6.1 Shimadzu Corporation Business Overview 7.6.2 Shimadzu Corporation Diffractive Elements Quarterly Production and Revenue, 2020 7.6.3 Shimadzu Corporation Diffractive Elements Product Introduction 7.6.4 Shimadzu Corporation Response to COVID-19 and Related Developments 7.7 Edmund Optics 7.7.1 Edmund Optics Business Overview 7.7.2 Edmund Optics Diffractive Elements Quarterly Production and Revenue, 2020 7.7.3 Edmund Optics Diffractive Elements Product Introduction 7.7.4 Edmund Optics Response to COVID-19 and Related Developments 7.8 Lightsmyth (Finisar) 7.8.1 Lightsmyth (Finisar) Business Overview 7.8.2 Lightsmyth (Finisar) Diffractive Elements Quarterly Production and Revenue, 2020 7.8.3 Lightsmyth (Finisar) Diffractive Elements Product Introduction 7.8.4 Lightsmyth (Finisar) Response to COVID-19 and Related Developments 7.9 Optometrics (Dynasil) 7.9.1 Optometrics (Dynasil) Business Overview 7.9.2 Optometrics (Dynasil) Diffractive Elements Quarterly Production and Revenue, 2020 7.9.3 Optometrics (Dynasil) Diffractive Elements Product Introduction 7.9.4 Optometrics (Dynasil) Response to COVID-19 and Related Developments 7.10 Kaiser Optical Systems 7.10.1 Kaiser Optical Systems Business Overview 7.10.2 Kaiser Optical Systems Diffractive Elements Quarterly Production and Revenue, 2020 7.10.3 Kaiser Optical Systems Diffractive Elements Product Introduction 7.10.4 Kaiser Optical Systems Response to COVID-19 and Related Developments 7.11 SUSS MicroTec AG. 7.11.1 SUSS MicroTec AG. Business Overview 7.11.2 SUSS MicroTec AG. Diffractive Elements Quarterly Production and Revenue, 2020 7.11.3 SUSS MicroTec AG. Diffractive Elements Product Introduction 7.11.4 SUSS MicroTec AG. Response to COVID-19 and Related Developments 7.12 Photop Technologies 7.12.1 Photop Technologies Business Overview 7.12.2 Photop Technologies Diffractive Elements Quarterly Production and Revenue, 2020 7.12.3 Photop Technologies Diffractive Elements Product Introduction 7.12.4 Photop Technologies Response to COVID-19 and Related Developments 7.13 Wasatch Photonics 7.13.1 Wasatch Photonics Business Overview 7.13.2 Wasatch Photonics Diffractive Elements Quarterly Production and Revenue, 2020 7.13.3 Wasatch Photonics Diffractive Elements Product Introduction 7.13.4 Wasatch Photonics Response to COVID-19 and Related Developments 7.14 Headwall Photonics 7.14.1 Headwall Photonics Business Overview 7.14.2 Headwall Photonics Diffractive Elements Quarterly Production and Revenue, 2020 7.14.3 Headwall Photonics Diffractive Elements Product Introduction 7.14.4 Headwall Photonics Response to COVID-19 and Related Developments 7.15 Plymouth Grating Lab 7.15.1 Plymouth Grating Lab Business Overview 7.15.2 Plymouth Grating Lab Diffractive Elements Quarterly Production and Revenue, 2020 7.15.3 Plymouth Grating Lab Diffractive Elements Product Introduction 7.15.4 Plymouth Grating Lab Response to COVID-19 and Related Developments 7.16 Spectrogon AB 7.16.1 Spectrogon AB Business Overview 7.16.2 Spectrogon AB Diffractive Elements Quarterly Production and Revenue, 2020 7.16.3 Spectrogon AB Diffractive Elements Product Introduction 7.16.4 Spectrogon AB Response to COVID-19 and Related Developments 7.17 RPC Photonics 7.17.1 RPC Photonics Business Overview 7.17.2 RPC Photonics Diffractive Elements Quarterly Production and Revenue, 2020 7.17.3 RPC Photonics Diffractive Elements Product Introduction 7.17.4 RPC Photonics Response to COVID-19 and Related Developments 7.18 SILIOS Technologies 7.18.1 SILIOS Technologies Business Overview 7.18.2 SILIOS Technologies Diffractive Elements Quarterly Production and Revenue, 2020 7.18.3 SILIOS Technologies Diffractive Elements Product Introduction 7.18.4 SILIOS Technologies Response to COVID-19 and Related Developments 7.19 GratingWorks 7.19.1 GratingWorks Business Overview 7.19.2 GratingWorks Diffractive Elements Quarterly Production and Revenue, 2020 7.19.3 GratingWorks Diffractive Elements Product Introduction 7.19.4 GratingWorks Response to COVID-19 and Related Developments 8 Supply Chain and Sales Channels Analysis 8.1 Diffractive Elements Supply Chain Analysis 8.1.1 Diffractive Elements Supply Chain Analysis 8.1.2 Covid-19 Impact on Diffractive Elements Supply Chain 8.2 Distribution Channels Analysis 8.2.1 Diffractive Elements Distribution Channels 8.2.2 Covid-19 Impact on Diffractive Elements Distribution Channels 8.2.3 Diffractive Elements Distributors 8.3 Diffractive Elements Customers 9 Key Findings 10 Appendix 10.1 About Us 10.2 Disclaimer

List of Tables Table 1. Overview of the World Economic Outlook Projections Table 2. Summary of World Real per Capita Output (Annual percent change; in international currency at purchasing power parity) Table 3. European Economies: Real GDP, Consumer Prices, Current Account Balance, and Unemployment (Annual percent change, unless noted otherwise) Table 4. Asian and Pacific Economies: Real GDP, Consumer Prices, Current Account Balance, and Unemployment (Annual percent change, unless noted otherwise) Table 5. Western Hemisphere Economies: Real GDP, Consumer Prices, Current Account Balance, and Unemployment (Annual percent change, unless noted otherwise) Table 6. Middle Eastern and Central Asian Economies: Real GDP, Consumer Prices, Current Account Balance, and Unemployment (Annual percent change, unless noted otherwise) Table 7. Covid-19 Impact: Global Major Government Policy Table 8. The Covid-19 Impact on Diffractive Elements Assessment Table 9. COVID-19 Impact: Diffractive Elements Market Trends Table 10. COVID-19 Impact Global Diffractive Elements Market Size Table 11. Global Diffractive Elements Market Size Pre-COVID-19 and Post- COVID-19 Comparison, 2015-2026 (K Units) Table 12. Global Diffractive Elements Price, Pre-COVID-19 and Post- COVID-19 Comparison, 2015-2026, (USD/Unit) Table 13. Global Diffractive Elements Quarterly Market Size, 2020 (US$ Million) & (K Units) Table 14. Global Diffractive Elements Market Size, Pre-COVID-19 and Post- COVID-19 Quarterly Comparison, 2020-2021 (US$ Million) Table 15. Global Diffractive Elements Market Size, Pre-COVID-19 and Post- COVID-19 Quarterly Comparison, 2020-2021 (K Units) Table 16. Global Diffractive Elements Market Growth Drivers Table 17. Global Diffractive Elements Market Restraints Table 18. Global Diffractive Elements Market Opportunities Table 19. Global Diffractive Elements Market Challenges Table 20. Key Manufacturers Diffractive Elements Quarterly Revenue, 2019 VS 2020 (US$ Million) Table 21. Top Manufacturers, Diffractive Elements Market Size, 2019 (K Units) & (US$ Million) Table 22. Diffractive Elements Factory Price by Manufacturers 2020 (USD/Unit) Table 23. Location of Key Manufacturers Diffractive Elements Manufacturing Plants Table 24. Key Manufacturers Diffractive Elements Market Served Table 25. Date of Key Manufacturers Enter into Diffractive Elements Market Table 26. Key Manufacturers Diffractive Elements Product Type Table 27. Mergers & Acquisitions, Expansion Plans Table 28. Global Diffractive Elements Market Size by Type, 2020, (US$ Million) Table 29. Global Diffractive Elements Market Size by Type, 2020 (K Units) Table 30. Global Diffractive Elements Price: by Type, 2020-2021 (USD/Unit) Table 31. Global Diffractive Elements Market Size by Application: 2020-2021 (US$ Million) Table 32. Global Diffractive Elements Market Size by Application, 2020-2021 (K Units) Table 33. Global Diffractive Elements Price: by Application, 2020-2021 (USD/Unit) Table 34. Global Diffractive Elements Market Size by Region, 2019-2021 (US$ Million) Table 35. Global Diffractive Elements Market Size by Region, 2019-2021 (K Units) Table 36. By Country, North America Diffractive Elements Market Size, 2019-2021 (US$ Million) Table 37. By Country, North America Diffractive Elements Market Size, 2019-2021 (K Units) Table 38. US Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 39. Canada Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 40. Macroeconomic Indicators of Europe (Germany, France, UK and Italy) Table 41. By Country, Europe Diffractive Elements Market Size, 2019-2021 (US$ Million) Table 42. By Country, Europe Diffractive Elements Market Size, 2019-2021 (K Units) Table 43. Germany Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 44. France Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 45. UK Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 46. Italy Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 47. Macroeconomic Indicators of Asia-Pacific (China, Japan, South Korea, India and ASEAN) Table 48. By Region, Asia-Pacific Diffractive Elements Market Size, 2019-2021 (US$ Million) Table 49. By Region, Asia-Pacific Diffractive Elements Market Size, 2019-2021 (K Units) Table 50. China Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 51. Japan Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 52. South Korea Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 53. India Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 54. ASEAN Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 55. Latin America Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 56. Middle East and Africa Diffractive Elements Market Size, 2019-2021 (US$ Million) & (K Units) Table 57. Jenoptik Business Overview Table 58. Jenoptik Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 59. Jenoptik Diffractive Elements Product Table 60. Jenoptik Response to COVID-19 and Related Developments Table 61. Holo/Or Ltd. Business Overview Table 62. Holo/Or Ltd. Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 63. Holo/Or Ltd. Diffractive Elements Product Table 64. Holo/Or Ltd. Response to COVID-19 and Related Developments Table 65. HORIBA Business Overview Table 66. HORIBA Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 67. HORIBA Diffractive Elements Product Table 68. HORIBA Response to COVID-19 and Related Developments Table 69. Newport Corporation Business Overview Table 70. Newport Corporation Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 71. Newport Corporation Diffractive Elements Product Table 72. Newport Corporation Response to COVID-19 and Related Developments Table 73. Zeiss Business Overview Table 74. Zeiss Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 75. Zeiss Diffractive Elements Product Table 76. Zeiss Response to COVID-19 and Related Developments Table 77. Shimadzu Corporation Business Overview Table 78. Shimadzu Corporation Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 79. Shimadzu Corporation Diffractive Elements Product Table 80. Shimadzu Corporation Response to COVID-19 and Related Developments Table 81. Edmund Optics Business Overview Table 82. Edmund Optics Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 83. Edmund Optics Diffractive Elements Product Table 84. Edmund Optics Response to COVID-19 and Related Developments Table 85. Lightsmyth (Finisar) Business Overview Table 86. Lightsmyth (Finisar) Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 87. Lightsmyth (Finisar) Diffractive Elements Product Table 88. Lightsmyth (Finisar) Response to COVID-19 and Related Developments Table 89. Optometrics (Dynasil) Business Overview Table 90. Optometrics (Dynasil) Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 91. Optometrics (Dynasil) Diffractive Elements Product Table 92. Optometrics (Dynasil) Response to COVID-19 and Related Developments Table 93. Kaiser Optical Systems Business Overview Table 94. Kaiser Optical Systems Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 95. Kaiser Optical Systems Diffractive Elements Product Table 96. Kaiser Optical Systems Response to COVID-19 and Related Developments Table 97. SUSS MicroTec AG. Business Overview Table 98. SUSS MicroTec AG. Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 99. SUSS MicroTec AG. Diffractive Elements Product Table 100. SUSS MicroTec AG. Response to COVID-19 and Related Developments Table 101. Photop Technologies Business Overview Table 102. Photop Technologies Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 103. Photop Technologies Diffractive Elements Product Table 104. Photop Technologies Response to COVID-19 and Related Developments Table 105. Wasatch Photonics Business Overview Table 106. Wasatch Photonics Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 107. Wasatch Photonics Diffractive Elements Product Table 108. Wasatch Photonics Response to COVID-19 and Related Developments Table 109. Headwall Photonics Business Overview Table 110. Headwall Photonics Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 111. Headwall Photonics Diffractive Elements Product Table 112. Headwall Photonics Response to COVID-19 and Related Developments Table 113. Plymouth Grating Lab Business Overview Table 114. Plymouth Grating Lab Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 115. Plymouth Grating Lab Diffractive Elements Product Table 116. Plymouth Grating Lab Response to COVID-19 and Related Developments Table 117. Spectrogon AB Business Overview Table 118. Spectrogon AB Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 119. Spectrogon AB Diffractive Elements Product Table 120. Spectrogon AB Response to COVID-19 and Related Developments Table 121. RPC Photonics Business Overview Table 122. RPC Photonics Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 123. RPC Photonics Diffractive Elements Product Table 124. RPC Photonics Response to COVID-19 and Related Developments Table 125. SILIOS Technologies Business Overview Table 126. SILIOS Technologies Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 127. SILIOS Technologies Diffractive Elements Product Table 128. SILIOS Technologies Response to COVID-19 and Related Developments Table 129. GratingWorks Business Overview Table 130. GratingWorks Diffractive Elements Production (K Units), Revenue (US$ Million), Price (USD/Unit) and Gross Margin, (Q1, Q2, Q3, Q4) Quarter 2020 Table 131. GratingWorks Diffractive Elements Product Table 132. GratingWorks Response to COVID-19 and Related Developments Table 133. Diffractive Elements Distributors List Table 134. Diffractive Elements Customers List Table 135. Covid-19 Impact on Diffractive Elements Customers List of Figures Figure 1. Diffractive Elements Product Picture Figure 2. Diffractive Elements Market Segmentation Figure 3. Research Objectives Figure 4. Research Process Figure 5. Data Triangulation Figure 6. Research Approach Figure 7. Commodity Prices-Metals Price Indices Figure 8. Commodity Prices- Precious Metal Price Indices Figure 9. Commodity Prices- Agricultural Raw Material Price Indices Figure 10. Commodity Prices- Food and Beverage Price Indices Figure 11. Commodity Prices- Fertilizer Price Indices Figure 12. Commodity Prices- Energy Price Indices Figure 13. G20+: Economic Policy Responses to COVID-19 Figure 14. Global Diffractive Elements Market Size, Pre-COVID-19 and Post- COVID-19 Comparison, 2015-2026 (US$ Million) Figure 15. Global Diffractive Elements Market Size, Pre-COVID-19 and Post- COVID-19, Year-over-Year Growth Rate, 2015-2026 (%) Figure 16. Global Diffractive Elements Market Size, Quarterly Growth, 2020-2021 (%) Figure 17. Global Diffractive Elements Market Size, Market Share by Type, 2019 VS 2020 (%) Figure 18. Global Diffractive Elements Market Size, Market Share by Application, 2019 VS 2020 (%) Figure 19. Global Diffractive Elements Market Size Market Share by Region, 2019 VS 2020 (%) Figure 20. United States Composite PMI and GDP Figure 21. Eurozone Composite PMI and GDP Figure 22. Eurozone Core v. Periphery PMI Output Indices Figure 23. Core v. Periphery PMI Employment Indices Figure 24. UK Composite PMI and GDP Figure 25. Caixin China Composite Output Index Figure 26. Caixin China General Services Business Activity Index Figure 27. Japan Composite Output Index Figure 28. South Korea Manufacturing PMI Figure 29. India Composite Output Index Figure 30. ASEAN Manufacturing PMI Figure 31. By Region, Asia-Pacific Diffractive Elements Market Size Market Share, 2019-2021

Jenoptik Holo/Or Ltd. HORIBA Newport Corporation Zeiss Shimadzu Corporation Edmund Optics Lightsmyth (Finisar) Optometrics (Dynasil) Kaiser Optical Systems SUSS MicroTec AG. Photop Technologies Wasatch Photonics Headwall Photonics Plymouth Grating Lab Spectrogon AB RPC Photonics SILIOS Technologies GratingWorks