Results 251 to 260 of about 70,563 (294)
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Deformable segmented mems mirror
The Journal of the Acoustical Society of America, 2005A MEMS device having a deformable segmented mirror. The mirror includes a plurality of movable segments supported on a substrate using spring vertices, each vertex having a fixed plate and one or more springs. In a representative embodiment, three springs support each movable segment, where each spring connects the movable segment to a different spring
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Edge-Control on Mirror Segments
International Optical Design Conference and Optical Fabrication and Testing, 2010We outline requirements for mirror segment edges for extremely large telescopes, and introduce the new CNC machine for process verification. We review a promising approach for edge-control using the Precessions process, and report progress.
David Walker +3 more
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Segmented active / adaptive thin shell mirrors
Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation VICurrent ELTs use comparatively thick segmented mirrors with a support structure / warping structure of significant mass. In this publication we present a method to develop Segmented Thin Shell Mirrors that are intended to be supported by multiple actuators mounted on a backing structure.
Speet, B. +6 more
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Segmented mirror adaptive optics system
Annual Meeting Optical Society of America, 1987An adaptive optics system that utilizes a segmented mirror as the active component is described and discussed. The mirror is a 10-in. diam spherical mirror composed of 13 independently controllable segments of equal area. The system linearity and control laws are discussed assuming a modal wavefront expansion.
John D. Downie +2 more
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Segmented bimorph mirrors for adaptive optics: segment design and experiment
Applied Optics, 2014We discuss the concept of lightweight segmented bimorph mirrors for adaptive optics. The segment consists of a monocrystal silicon substrate actuated by an array of in-plane piezoceramic (PZT) actuators with honeycomb electrodes. We focus on technological aspects of the segment design that are critical for space applications and describe a single ...
Bastaits, Renaud +7 more
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Segmented Mirrors For Atmospheric Compensation
SPIE Proceedings, 1989An optical wavefront propagating through the atmosphere will be perturbed by local variations in the refractive index of the 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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Mirror antenna with hexagonal segmentation
International Symposium on Antennas and Propagation Society, Merging Technologies for the 90's, 1990The antenna designed for radiometer applications on the planned NASA Earth Science Geostationary Platforms is described. This antenna consists of two parts: a regular parabolic dish 5 m in diameter which converts the radiation from feeds into a collimated beam, and a movable mirror that redirects the beam to a prescribed scan direction.
B. Houshmand +3 more
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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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