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Position sensors for segmented mirror
SPIE Proceedings, 2004There are currently several projects for giant telescopes with segmented mirrors under way. These future telescopes will have their primary mirror made of several thousand segments. The main advantage of segmentation is that it enables the active control of the whole mirror, so as to suppress the deformations of the support structure due to the wind ...
Didier Roziere +2 more
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Segmented mirrors for atmospheric compensation
Optical Engineering, 1990An optical wavefront propagating through the atmosphere will be perturbed by local variations in the refractive index ofthe atmospheric gases. When accumulated over long optical path distances they will impart a spatial and temporally random distortion to the wavefront.
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Fast tip-tilt segment alignment for segmented mirrors
SPIE Proceedings, 2016A method for fast identification of segments and alignment of the segmented mirrors has been developed and applied for the deformable mirror of the WHT AO system (NAOMI) and for the GTC 36-segment primary mirror. By moving each segment by a known but different amount and in a different direction it is possible to identify many segments simultaneously ...
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Optimal wavefront control for adaptive segmented mirrors
Applied Optics, 1989A ground-based astronomical telescope with a segmented primary mirror will suffer image-degrading wavefront aberrations from at least two sources: (1) atmospheric turbulence and (2) segment misalignment or figure errors of the mirror itself. This paper describes the derivation of a mirror control feedback matrix that assumes the presence of both types ...
J D, Downie, J W, Goodman
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Solar imaging with a segmented adaptive mirror
Applied Optics, 1992A 19-segment adaptive-mirror system is currently being used on the Sacramento Peak 76-cm Tower Telescope to remove wave-front distortions resulting from atmospheric turbulence. The system has proven to be capable of substantially improving the quality of an image, at times achieving 0.33-arcsec resolution in visible wavelengths under 1-3-arcsec seeing ...
D S, Acton, R C, Smithson
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Giant segmented adaptive mirrors: progress report
SPIE Proceedings, 2003We show that the same technology developed for MMT and LBT Adaptive Secondary mirrors can be used for building segmented adaptive mirrors of essentially any size. This seems to be at the moment the most promising approach to provide the enormous number of degrees of freedom necessary for adaptive correction at visual wavelengths in giant telescopes. In
Armando Riccardi +6 more
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Co-focus experiment of segmented mirror
Chinese Physics B, 2017In this paper, an active optics and co-focus experimental system of segmented mirror is built. Firstly, a support structure of segmented mirror is designed and it is verified by simulation to meet the requirement for the experimental system of segmented mirror.
Bin Li +4 more
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Polarization Interferometry For Segmented Mirror Phasing
Adaptive Optics for Large Telescopes, 1992This paper documents the design, construction and testing of a polarization interferometry based device for measuring the relative axial positioning of the individual segments of a multi-segment optical system. The device was designed to operate from an off-axis position in order to leave the central portion of the focal plane free for other sensors ...
J. D. Blum, T. A. Sebring
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Absolute phasing of segmented mirrors
Optical Society of America Annual Meeting, 1990Very large space-borne telescopes have primary mirrors made of several independent segments that must be aligned to a fraction of a wavelength for optimum performance. All proposed solutions for such phase alignment appear to have some limitations.
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Polishing TIM mirror segments with HyDra
SPIE Proceedings, 2003We report experimental results and analysis about a new hydrodynamic radial tool (HyDra, patent pending), which expels a suspension of water and polishing particles radially on glass. With this method it is possible to locally shape optical surfaces. The depth of material removed by HyDra grows linearly with the time. The removal rate is independent of
Alberto Cordero-Davila +13 more
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