Results 21 to 30 of about 26,046 (295)
Adaptive Optics and Optical Vortices [PDF]
, 2012 The achievement of minimal angular divergence of a laser beam is one of the most impor‐ tant problems in laser physics since many laser applications demand extreme concentration of radiation. Under the beam formation in the laser oscillator or amplifier with optically in‐ homogeneous gain medium and optical elements, the divergence usually exceeds the ...
F. A. Starikov +2 more
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Shack–Hartmann Wavefront Sensing Based on Four-Quadrant Binary Phase Modulation
Photonics, 2022 Aiming at the problem that it is difficult for the conventional Shack–Hartmann wavefront sensor to achieve high-precision wavefront reconstruction with low spatial sampling, a kind of Shack–Hartmann wavefront sensing technology based on four-quadrant ...
Mengmeng Zhao +7 more
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Sensors, 2023 A tip-tilt mirror (TTM) control method is designed to enhance the control bandwidth and ensure the rejection performance of the adaptive optics (AO) tip-tilt correction system.
Lingxi Kong +6 more
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Centroid-Predicted Deep Neural Network in Shack-Hartmann Sensors
IEEE Photonics Journal, 2022 The Shack-Hartmann wavefront sensor produces incorrect wavefront measurements when some sub-spots are weak and missing. In this paper, a method is proposed to predict the centroids of these sub-spots for the Shack-Hartmann wavefront sensor based on the ...
Mengmeng Zhao +6 more
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Delhi Journal of Ophthalmology, 2015 Physicists and ophthalmologists, since time immemorial have aggressively tried to break new ground in trying to get a good look at the retina and its myriad pathologies. Although fundus photography, optical coherence tomography and fundus fluorescein angiography have largely been very successful in imaging the retina and give a clear understanding of ...
Apoorva Ayachit +6 more
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IEEE Photonics JournalStabilization of optical beams has always been a key factor affecting the performance of many optical systems. The Adaptive optics (AO) beam stabilization system requires further development to cope with increasingly complex application scenarios and ...
Sicheng Guo +6 more
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The Extreme Learning Machine for the Extraction of Mono-Exponential Decay Time
IEEE Photonics Journal, 2023 The mono-exponential decay has been used to describe various physical phenomena such as cavity ring-down signal, fluorescence decay, etc. In this paper, a neural network method of extreme learning machine (ELM) is adopted to efficiently extract decay ...
Xing He +4 more
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Optics Express, 2019 We present a new Point Diffraction Interferometer (PDI). Binary adaptive optics (BAO) and Quaternary Adaptive Optics (QAO) can be performed with the help of this PDI as a wavefront sensor. The PDI interferogram, once binarized, is used in two consecutive steps to produce a quaternary mask with phase values 0, π/2, π and 3π/2.
Manuel P. Cagigal +5 more
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Optimization of Iterative Control Algorithms for High-Resolution Adaptive Optics Systems
IEEE Photonics JournalAs the number of wavefront sensor subapertures and deformable mirror actuators in adaptive optics systems increases, the computational time of the direct gradient wavefront control algorithm is excessively long, which is a major factor affecting the ...
Shenghu Liu +7 more
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Opto-Electronic Advances, 2023 Integrating deformable mirrors within the optical train of an adaptive telescope was one of the major innovations in astronomical observation technology, distinguished by its high optical throughput, reduced optical surfaces, and the incorporation of the
Youming Guo +9 more
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