Results 1 to 10 of about 1,304 (181)

Optical Enhancement of Diffraction Efficiency of Texas Instruments Phase Light Modulator for Beam Steering in Near Infrared

Micromachines, 2022
Phase light modulator (PLM) by MEMS mirror array operating in a piston-mode motion enables a high-speed diffractive beam steering in a random-access and flexible manner that makes a lidar system more intelligent and adaptive.
Jiafan Guan, Zhipeng Dong, Xianyue Deng, Yuzuru Takashima   +3 more
doaj   +1 more source

Piston Error Measurement for Segmented Telescopes with an Artificial Neural Network

Sensors, 2021
A piston error detection method is proposed based on the broadband intensity distribution on the image plane using a back-propagation (BP) artificial neural network.
Dan Yue, Yihao He, Yushuang Li
doaj   +1 more source

In-Situ Metrology of Large Segmented Detector Based on Modified Optical Truss

IEEE Photonics Journal, 2023
To precisely map cosmic structures and capture time-domain events, future large survey telescopes will be equipped with segmented detectors that greatly expand their field of view. Segment flatness and assembly accuracy will be essential for them to make
Qichang An, Hanfu Zhang, Xiaoxia Wu, Jianli Wang, Tao Chen, Jingxu Zhang, Hongwen Li   +6 more
doaj   +1 more source

A universal framework for microscope sensorless adaptive optics: Generalized aberration representations

APL Photonics, 2020
Adaptive optics (AO) methods are widely used in microscopes to improve image quality through correction of phase aberrations. A range of wavefront-sensorless AO schemes exist, such as modal, pupil segmentation zonal, and pixelated piston-based methods ...
Q. Hu, J. Wang, J. Antonello, M. Hailstone, M. Wincott, R. Turcotte, D. Gala, M. J. Booth   +7 more
doaj   +1 more source

Oil Film Formation of Reciprocating Seals Observed by Interferometry

Tribology Online, 2014
Oil film thickness in rubber piston seals is measured by interferometry. Optimized optics and fluids enable clear interferograms. The oil film thickness on the contact area is measured during reciprocating motion.
Kenichi Yoshimura, Nozomu Suzuki, Hirotaka Mizuta   +2 more
doaj   +1 more source

A Compact Tunable Diode Laser Absorption Spectrometer to Monitor CO2 at 2.7 µm Wavelength in Hypersonic Flows

Sensors, 2010
Since the beginning of the Mars planet exploration, the characterization of carbon dioxide hypersonic flows to simulate a spaceship’s Mars atmosphere entry conditions has been an important issue.
Raphäel Vallon, Jacques Soutadé, Jean-Luc Vérant, Jason Meyers, Sébastien Paris, Ajmal Mohamed   +5 more
doaj   +1 more source

Experimental Demonstration of Coherent Combining With Tip/Tilt Control Based on Adaptive Space-to-Fiber Laser Beam Coupling

IEEE Photonics Journal, 2017
A novel approach of tip/tilt control through optimizing laser beam coupling efficiencies from space to polarization-maintaining-fibers with stochastic parallel gradient descent (SPGD) algorithm for coherent beam combining (CBC) applications is ...
Feng Li, Chao Geng, Guan Huang, Yan Yang, Xinyang Li, Qi Qiu   +5 more
doaj   +1 more source

Operation of a MOEMS Deformable Mirror in Cryo: Challenges and Results

Micromachines, 2017
Micro-opto-electro-mechanical systems (MOEMS) Deformable Mirrors (DM) are key components for next generation optical instruments implementing innovative adaptive optics systems, both in existing telescopes and in the future ELTs.
Frederic Zamkotsian, Patrick Lanzoni, Rudy Barette, Michael Helmbrecht, Franck Marchis, Alex Teichman   +5 more
doaj   +1 more source

Realization of large energy proportion in the central lobe by coherent beam combination based on conformal projection system

Scientific Reports, 2017
In this paper, we experimentally validate a tiled-aperture conformal projection system with the largest array filling factor and element beam truncation factor to the best of our knowledge. The conformal projection system, which is made up of a hexagonal
Dong Zhi, Zhixin Zhang, Yanxing Ma, Xiaolin Wang, Zilun Chen, Wuming Wu, Pu Zhou, Lei Si   +7 more
doaj   +1 more source

Mode-Voltage Constrained Control for Adaptive Optics System

IEEE Photonics Journal
In the adaptive optics system of astronomical observation, the deformable mirror and the tip/tilt mirror are coupled during the correction process.
Ruitao Wang, Youming Guo, Nanfei Yan, Ying Yang, Lanqiang Zhang, Qiong Tu, Lingxiao Li, Changhui Rao   +7 more
doaj   +1 more source