Active control of edges and global microstructure on segmented mirrors

D. D. Walker, A. Beaucamp, C. Dunn, R. Evans, R. Freeman, R. Morton, S. Wei, G. Yu

Research output: Chapter in Book/Report/Conference proceedingConference contribution

13 Citations (Scopus)

Abstract

In this paper we address two interrelated issues important to primary mirror segments for extremely large telescopes - edge-control, and the detailed topography over the segment surface. Both affect the intensity and distribution of stray light and infrared emissivity. CNC polishing processes typically deploy spiral or raster tool-paths, tending to leave repetitive features. We compare and contrast two novel families of pseudo-random tool-paths for Precessions CNC polishing. We then show how CNC control of the three-dimensional tool-path can optimize edge-profiles. Finally, we demonstrate fluid-jet polishing used to clean up residual edge defects.

Original languageEnglish
Title of host publicationAdvanced Optical and Mechanical Technologies in Telescopes and Instrumentation
Subtitle of host publicationSPIE Astronomical Telescopes and Instrumentation 2008
EditorsEli Atad-Ettedgui, Dietrich Lemke
PublisherSPIE
Number of pages9
Volume7018
ISBN (Print)9780819472281
DOIs
Publication statusPublished - 23 Jul 2008
Externally publishedYes
EventAdvanced Optical and Mechanical Technologies in Telescopes and Instrumentation - Marseille, France
Duration: 23 Jun 200828 Jun 2008

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
Volume7018
ISSN (Print)0277-786X

Conference

ConferenceAdvanced Optical and Mechanical Technologies in Telescopes and Instrumentation
CountryFrance
CityMarseille
Period23/06/0828/06/08

Fingerprint

Segmented Mirror
segmented mirrors
Tool Path
Polishing
Active Control
active control
polishing
Microstructure
microstructure
fluid jets
Stray light
Extremely Large Telescopes
Stray Light
Emissivity
Topography
emissivity
precession
Telescopes
Mirror
topography

Cite this

Walker, D. D., Beaucamp, A., Dunn, C., Evans, R., Freeman, R., Morton, R., ... Yu, G. (2008). Active control of edges and global microstructure on segmented mirrors. In E. Atad-Ettedgui, & D. Lemke (Eds.), Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation: SPIE Astronomical Telescopes and Instrumentation 2008 (Vol. 7018). [701812] (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 7018). SPIE. https://doi.org/10.1117/12.787930
Walker, D. D. ; Beaucamp, A. ; Dunn, C. ; Evans, R. ; Freeman, R. ; Morton, R. ; Wei, S. ; Yu, G. / Active control of edges and global microstructure on segmented mirrors. Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation: SPIE Astronomical Telescopes and Instrumentation 2008. editor / Eli Atad-Ettedgui ; Dietrich Lemke. Vol. 7018 SPIE, 2008. (Proceedings of SPIE - The International Society for Optical Engineering).
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Walker, DD, Beaucamp, A, Dunn, C, Evans, R, Freeman, R, Morton, R, Wei, S & Yu, G 2008, Active control of edges and global microstructure on segmented mirrors. in E Atad-Ettedgui & D Lemke (eds), Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation: SPIE Astronomical Telescopes and Instrumentation 2008. vol. 7018, 701812, Proceedings of SPIE - The International Society for Optical Engineering, vol. 7018, SPIE, Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation, Marseille, France, 23/06/08. https://doi.org/10.1117/12.787930

Active control of edges and global microstructure on segmented mirrors. / Walker, D. D.; Beaucamp, A.; Dunn, C.; Evans, R.; Freeman, R.; Morton, R.; Wei, S.; Yu, G.

Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation: SPIE Astronomical Telescopes and Instrumentation 2008. ed. / Eli Atad-Ettedgui; Dietrich Lemke. Vol. 7018 SPIE, 2008. 701812 (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 7018).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Walker DD, Beaucamp A, Dunn C, Evans R, Freeman R, Morton R et al. Active control of edges and global microstructure on segmented mirrors. In Atad-Ettedgui E, Lemke D, editors, Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation: SPIE Astronomical Telescopes and Instrumentation 2008. Vol. 7018. SPIE. 2008. 701812. (Proceedings of SPIE - The International Society for Optical Engineering). https://doi.org/10.1117/12.787930