Technology for eight-metre primary mirrors

Richard G. Bingham, David D. Walker, Francisco Diego

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

Abstract

The cost of an eight-metre telescope is still too high for most national observatories. Cost reductions must involve new technology for the primary mirror: its material and figuring, its mass, handling and the aluminising plant. Our scheme which addresses these problems uses some features of the Keck technology, but is simplified. Necessary R&D can be carried out at our facility in London. We consider a segmented mirror in which the segments are radially-cut sectors. The sectors for an eight-metre aperture will fit inside a four-metre aluminising plant (which already exists on some sites, and in any event is cheaper than an eight-metre plant). Zero-expansion material (glass-ceramic or fused silica) may be used. The model thickness is about ten centimetres. The proposed method of production is to figure the whole set assembled as a single mirror. No cutting takes place after figuring. We consider three such figuring methods including inverted polishing and a new 'stressed mirror figuring' approach. (These methods are partly applicable to monolithic mirrors). In one of these methods, the support system of our assembled mirror on the machine may perhaps be re-used on the telescope. We expect that the testing and figuring cycle can be controlled sufficiently accurately to provide mirror segments which are interchangeable between successive batches. The economies produced by this technology may also be effective for smaller telescopes.

Original languageEnglish
Title of host publicationAdvanced Technology Optical Telescopes IV
Subtitle of host publicationSPIE Astronomical Telescopes and Instrumentation for the 21st Century 1990
EditorsLawrence D. Barr
PublisherSPIE
Pages586-596
Number of pages11
ISBN (Print)081940280X, 9780819420806
DOIs
Publication statusPublished - 1 Jul 1990
Externally publishedYes
EventAdvanced Technology Optical Telescopes IV - Tuscon, United States
Duration: 12 Feb 199016 Feb 1990
Conference number: 4

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
Volume1236 pt 2
ISSN (Print)0277-786X

Conference

ConferenceAdvanced Technology Optical Telescopes IV
CountryUnited States
CityTuscon
Period12/02/9016/02/90

Fingerprint

Mirrors
mirrors
Telescopes
telescopes
sectors
segmented mirrors
cost reduction
support systems
Glass ceramics
economy
Observatories
Fused silica
Cost reduction
Polishing
polishing
observatories
apertures
ceramics
silicon dioxide
costs

Cite this

Bingham, R. G., Walker, D. D., & Diego, F. (1990). Technology for eight-metre primary mirrors. In L. D. Barr (Ed.), Advanced Technology Optical Telescopes IV: SPIE Astronomical Telescopes and Instrumentation for the 21st Century 1990 (pp. 586-596). (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 1236 pt 2). SPIE. https://doi.org/10.1117/12.19228
Bingham, Richard G. ; Walker, David D. ; Diego, Francisco. / Technology for eight-metre primary mirrors. Advanced Technology Optical Telescopes IV: SPIE Astronomical Telescopes and Instrumentation for the 21st Century 1990. editor / Lawrence D. Barr. SPIE, 1990. pp. 586-596 (Proceedings of SPIE - The International Society for Optical Engineering).
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Bingham, RG, Walker, DD & Diego, F 1990, Technology for eight-metre primary mirrors. in LD Barr (ed.), Advanced Technology Optical Telescopes IV: SPIE Astronomical Telescopes and Instrumentation for the 21st Century 1990. Proceedings of SPIE - The International Society for Optical Engineering, vol. 1236 pt 2, SPIE, pp. 586-596, Advanced Technology Optical Telescopes IV, Tuscon, United States, 12/02/90. https://doi.org/10.1117/12.19228

Technology for eight-metre primary mirrors. / Bingham, Richard G.; Walker, David D.; Diego, Francisco.

Advanced Technology Optical Telescopes IV: SPIE Astronomical Telescopes and Instrumentation for the 21st Century 1990. ed. / Lawrence D. Barr. SPIE, 1990. p. 586-596 (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 1236 pt 2).

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

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M3 - Conference contribution

SN - 081940280X

SN - 9780819420806

T3 - Proceedings of SPIE - The International Society for Optical Engineering

SP - 586

EP - 596

BT - Advanced Technology Optical Telescopes IV

A2 - Barr, Lawrence D.

PB - SPIE

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Bingham RG, Walker DD, Diego F. Technology for eight-metre primary mirrors. In Barr LD, editor, Advanced Technology Optical Telescopes IV: SPIE Astronomical Telescopes and Instrumentation for the 21st Century 1990. SPIE. 1990. p. 586-596. (Proceedings of SPIE - The International Society for Optical Engineering). https://doi.org/10.1117/12.19228