Towards freeform manufacturing of ultra-low expansion glass optics
Ultra-Low-Expansion glass (ULE®) has become an important technological enabler of advanced imaging for astronomy and for extreme-UV lithography. A major limitation though, is that ULE® cannot be poured from the fluid state unlike ZERODUR® which renders costly to produce large and/or complex shapes f...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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EDP Sciences
2023-01-01
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| Series: | EPJ Web of Conferences |
| Online Access: | https://www.epj-conferences.org/articles/epjconf/pdf/2023/13/epjconf_eosam2023_05012.pdf |
| _version_ | 1797634841537150976 |
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| author | Benketaf Samuel Torun Gözden Bellouard Yves |
| author_facet | Benketaf Samuel Torun Gözden Bellouard Yves |
| author_sort | Benketaf Samuel |
| collection | DOAJ |
| description | Ultra-Low-Expansion glass (ULE®) has become an important technological enabler of advanced imaging for astronomy and for extreme-UV lithography. A major limitation though, is that ULE® cannot be poured from the fluid state unlike ZERODUR® which renders costly to produce large and/or complex shapes from it. Beside mirrors, optical components are rarely made of ULE® despite it sharing many properties of pure fused silica glass. Here we explore how femtosecond laser processing combined with laser induced reflow can be used to structure ULE® glass with the goal of producing miniature optical components. To fulfil optical roughness requirements, we adopt a strategy based on first producing elementary shapes, such as cubes or cylinders, that we further topologically transform into sphere, ellipsoids or curved surfaces, using a laser-reflow process. The structural modification of the glass matrix induced by the reflow were investigated using Raman spectroscopy. Our result points to a densification of the glass but no apparent sign of crystallization or devitrification. Furthermore, to understand whether the thermo-mechanical properties were affected or not, the thermal expansion coefficient was estimated using a dilatometry technic based on a pseudo-bimorph micro-cantilevers in a temperature-controlled chamber. |
| first_indexed | 2024-03-11T12:14:07Z |
| format | Article |
| id | doaj.art-c805877ac51b471c838d007dc82d6007 |
| institution | Directory Open Access Journal |
| issn | 2100-014X |
| language | English |
| last_indexed | 2024-03-11T12:14:07Z |
| publishDate | 2023-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | EPJ Web of Conferences |
| spelling | doaj.art-c805877ac51b471c838d007dc82d60072023-11-07T10:20:47ZengEDP SciencesEPJ Web of Conferences2100-014X2023-01-012870501210.1051/epjconf/202328705012epjconf_eosam2023_05012Towards freeform manufacturing of ultra-low expansion glass opticsBenketaf Samuel0Torun Gözden1Bellouard Yves2Galatea Laboratory, IEM/STI, Ecole Polytechnique Fédéral de Lausanne (EPFL)Galatea Laboratory, IEM/STI, Ecole Polytechnique Fédéral de Lausanne (EPFL)Galatea Laboratory, IEM/STI, Ecole Polytechnique Fédéral de Lausanne (EPFL)Ultra-Low-Expansion glass (ULE®) has become an important technological enabler of advanced imaging for astronomy and for extreme-UV lithography. A major limitation though, is that ULE® cannot be poured from the fluid state unlike ZERODUR® which renders costly to produce large and/or complex shapes from it. Beside mirrors, optical components are rarely made of ULE® despite it sharing many properties of pure fused silica glass. Here we explore how femtosecond laser processing combined with laser induced reflow can be used to structure ULE® glass with the goal of producing miniature optical components. To fulfil optical roughness requirements, we adopt a strategy based on first producing elementary shapes, such as cubes or cylinders, that we further topologically transform into sphere, ellipsoids or curved surfaces, using a laser-reflow process. The structural modification of the glass matrix induced by the reflow were investigated using Raman spectroscopy. Our result points to a densification of the glass but no apparent sign of crystallization or devitrification. Furthermore, to understand whether the thermo-mechanical properties were affected or not, the thermal expansion coefficient was estimated using a dilatometry technic based on a pseudo-bimorph micro-cantilevers in a temperature-controlled chamber.https://www.epj-conferences.org/articles/epjconf/pdf/2023/13/epjconf_eosam2023_05012.pdf |
| spellingShingle | Benketaf Samuel Torun Gözden Bellouard Yves Towards freeform manufacturing of ultra-low expansion glass optics EPJ Web of Conferences |
| title | Towards freeform manufacturing of ultra-low expansion glass optics |
| title_full | Towards freeform manufacturing of ultra-low expansion glass optics |
| title_fullStr | Towards freeform manufacturing of ultra-low expansion glass optics |
| title_full_unstemmed | Towards freeform manufacturing of ultra-low expansion glass optics |
| title_short | Towards freeform manufacturing of ultra-low expansion glass optics |
| title_sort | towards freeform manufacturing of ultra low expansion glass optics |
| url | https://www.epj-conferences.org/articles/epjconf/pdf/2023/13/epjconf_eosam2023_05012.pdf |
| work_keys_str_mv | AT benketafsamuel towardsfreeformmanufacturingofultralowexpansionglassoptics AT torungozden towardsfreeformmanufacturingofultralowexpansionglassoptics AT bellouardyves towardsfreeformmanufacturingofultralowexpansionglassoptics |