Results 11 to 20 of about 39,077 (276)
Remote Sensing, 2022 A segmented primary mirror is very important for extra-large astronomical telescopes, in order to detect the phase error between segmented mirrors. Traditional iterative algorithms are hard to detect co−phasing aberrations in real time due to the long ...
Yirui Wang +4 more
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Mirrors with regular hexagonal segments [PDF]
Applied Optics, 2003 The point-spread function and emissivity are calculated for a mirror made from regular hexagonal segments of just a few different sizes. A mirror of this type has many similar segments, which is an advantage for manufacturing, and for an approximately f/1 mirror with > or = 1000 segments and > or = 4 sizes of regular hexagons the increase in ...
Dario, Amodei, Stephen, Padin
openaire +2 more sources
Coarse Phasing Detection Using Multiwavelength Wavefront
Photonics, 2023 Presently, the segmented mirror is the mainstream development direction of large-aperture telescopes. The key problem affecting the performance of segmented mirror telescopes concerns the co-phase of the segments. The segments’ co-phase includes the fine
Rongjie Qin, Zihao Yin, Yinnian Liu
doaj +1 more source
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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Towards Piston Fine Tuning of Segmented Mirrors through Reinforcement Learning
Applied Sciences, 2020 Unlike supervised machine learning methods, reinforcement learning allows an entity to learn how to deploy a task from experience rather than labeled data.
Dailos Guerra-Ramos +2 more
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A Novel Tandem Differential Edge Sensor Layout for Segmented Mirror Telescopes
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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Applied Sciences, 2020 Due to fabrication difficulties, separately-polished segmented mirrors cannot meet the co-phasing surface shape error requirements in the segmented telescope system.
Songhang Wu +4 more
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Spatial Spectrum Analysis of Wave-Front Correction with a Segmented Mirror [PDF]
, 2003 An expression is derived for the spatial power spectrum of wave-front errors after correction with a segmented mirror. This includes estimates of the spectral contributions of segment piston and tilt corrections and spatial aliasing by a regular array of
Padin, Stephen
core +1 more source
An Efficient Correction Algorithm for Eliminating Image Misalignment Effects on Co-Phasing Measurement Accuracy for Segmented Active Optics Systems. [PDF]
PLoS ONE, 2016 The misalignment between recorded in-focus and out-of-focus images using the Phase Diversity (PD) algorithm leads to a dramatic decline in wavefront detection accuracy and image recovery quality for segmented active optics systems.
Dan Yue +3 more
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Piston Error Measurement for Segmented Telescopes Based on a Hybrid Artificial Neural Network
Sensors, 2023 To address the difficulty and complexity of detecting piston errors for segmented telescopes, this paper proposes a new piston error measurement method based on a hybrid artificial neural network.
Dan Yue +3 more
doaj +1 more source