Results 1 to 10 of about 70,444 (175)
A Novel Tandem Differential Edge Sensor Layout for Segmented Mirror Telescopes [PDF]
Sensors, 2023 The performance of an active control system, crucial for the co-phase maintenance of segmented mirrors, is closely related to the spatial layout of sensors and actuators.
Yinlong Huo +5 more
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Imaging with Hexagonal Segmented Mirror [PDF]
Engineering and Technology Journal, 2012 Different hexagons configuration aperture models of the optical telescope mirror is carefully considered in this study. The point spread function and the modulation transfer function of a reference star using different hexagons configuration are computed
Fouad N. Hassan +2 more
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Design and Error Analysis of an Optical Measurement System for the Wavefront of Large-Aperture Segmented Mirror [PDF]
SensorsTo better meet the wavefront measurement requirements for large-aperture segmented mirrors after in-orbit deployment, this paper designs a measurement system based on an optical camera and targets.
Yukun He +5 more
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Design considerations for a highly segmented mirror [PDF]
Applied Optics, 2003 Design issues for a 30-m highly segmented mirror are explored, with emphasis on parametric models of simple, inexpensive segments. A mirror with many small segments offers cost savings through quantity production and permits high-order active and adaptive wave-front corrections.
Padin, Stephen
openaire +5 more sources
In-plane effects on segmented-mirror control [PDF]
Applied Optics, 2012 Extremely large optical telescopes are being designed with primary mirrors composed of hundreds of segments. The "out-of-plane" piston, tip, and tilt degrees of freedom of each segment are actively controlled using feedback from relative height measurements between neighboring segments.
MacMynowski, Douglas G. +4 more
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Optimization of tangential interior brushless DC motor rotor for hybrid vehicles [PDF]
Scientific ReportsTo address performance degradation and demagnetization risks in hybrid electric vehicle oil pump motors under high-temperature conditions, this article proposes a novel rare-earth-free interior tangential brushless DC motor.
Xiaojing Li, Yingbo Zhang, Jiale Wu
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Piston Error Automatic Correction for Segmented Mirrors via Deep Reinforcement Learning [PDF]
SensorsThe segmented mirror co-phase error identification technique based on supervised learning methods has the advantages of simple application conditions, no dependence on custom sensors, a fast calculation speed, and low computing power requirements ...
Dequan Li, Dong Wang, Dejie Yan
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Active Optics and Aberration Correction Technology for Sparse Aperture Segmented Mirrors
Applied Sciences, 2023 Active optics and aberration correction techniques for sparse aperture segmented mirrors are studied. A finite element model of the sparse aperture segmented mirror was established, and a multi-aperture aberration polynomial was derived. According to the
Benlei Zhang +3 more
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Polarimetric characterization of segmented mirrors
Applied Optics, 2022 We study the impact of the loss of axial symmetry around the optical axis on the polarimetric properties of a telescope with a segmented primary mirror when each segment is present in a different aging stage. The different oxidation stage of each segment as it is substituted in time leads to nonnegligible cross-talk terms.
Pastor Yabar, A. +3 more
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Photonics, 2022 As the loading space in rockets and mirror fabrication technology is limited, optical systems in space cannot have large optical apertures. However, the successful launch and excellent performance of the James Webb Telescope indicate that segmented ...
Rongjie Qin +3 more
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