Results 11 to 20 of about 15,556 (304)

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, Fei Yang, Fuguo Wang, Peng Guo, Jiakang Zhu, Yuanguo Liu   +5 more
doaj   +2 more sources

ADAPTIVE OPTICS WITH SEGMENTED MIRROR OR DEFORMABLE MIRROR [PDF]

Le Journal de Physique Colloques, 1980
Two kinds of adaptive optics (COAT) are presented : one with segmented mirrors (COAT = 19) with 19 mirrors and actuators and the other with a continuously deformable mirror and 7 actuators. Each mirror of COAT 19 is moved by a piezoelectric actuator performing correction and modulation (dithering in the 12-24 kHz band).
Gaffard, J., Davila, C., de Miscault, J., Roger, G.   +3 more
openaire   +3 more sources

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   +4 more sources

Design and Error Analysis of an Optical Measurement System for the Wavefront of Large-Aperture Segmented Mirror [PDF]

Sensors
To 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, Hongbo Zhao, Lanxin Peng, Xiaodong Sui, Changzheng Chen, Yueyang Peng   +5 more
doaj   +2 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., Roberts, Lewis C., Jr., Shelton, J. Chris, Chanan, Gary, Bonnet, Henty   +4 more
openaire   +5 more sources

Design and Research of Large-Scale Curvature Adjustment Optical Mirror [PDF]

Photonics
This study introduces an optimization design method for large-scale curvature-adjustable optical mirrors, innovatively integrating parametric modeling with the optimized layout of actuators, targeting the achievement of extensive curvature adjustability ...
Kailun Zhao, Liuxing Song, Dewei Sun, Qiaolin Huang, Rongguang Guo, Guoliang Tian, Jinping He   +6 more
doaj   +2 more sources

Optimization of tangential interior brushless DC motor rotor for hybrid vehicles [PDF]

Scientific Reports
To 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
doaj   +2 more sources

Piston Error Automatic Correction for Segmented Mirrors via Deep Reinforcement Learning [PDF]

Sensors
The 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
doaj   +2 more sources

Polarization aberrations in next-generation giant segmented mirror telescopes (GSMTs) [PDF]

, 2023
Context. Next-generation large segmented mirror telescopes are expected to perform direct imaging and characterization of Earth-like rocky planets, which requires contrast limits of 10−7 to 10−8 at wavelengths from I to J band.
Doelman, David, Doelman, D.S., Douglas, E.S., Ashcraft, Jaren N., Skidmore, Warren, Rob G. van Holstein, Sebastiaan Y. Haffert, Warren Skidmore, Holstein, R.G. van, Gorkom, K. van, van Holstein, R.G., Ewan S. Douglas, Haffert, Sebastiaan Y., Maxwell A. Millar-Blanchaer, Anche, R.M., Doelman, D., Van Gorkom, Kyle, Williams, G., van Gorkom, K., Ramya M. Anche, David Doelman, Snik, Frans, van Holstein, Rob G., Millar-Blanchaer, M.A., Snik, F., Williams, Grant, Jaren N. Ashcraft, Anche, Ramya M., Haffert, S.Y., Ashcraft, J.N., Millar-Blanchaer, Maxwell A., Frans Snik, Kyle Van Gorkom, Douglas, Ewan S., Skidmore, W., Grant Williams   +35 more
core   +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