Results 21 to 30 of about 3,906 (246)
Wavefront sensing with a thin diffuser [PDF]
Optics Letters, 2017 We propose and implement a broadband, compact, and low-cost wavefront sensing scheme by simply placing a thin diffuser in the close vicinity of a camera. The local wavefront gradient is determined from the local translation of the speckle pattern. The translation vector map is computed thanks to a fast diffeomorphic image registration algorithm and ...
Berto, Pascal +2 more
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Method for distortion correction of multi-layered surface reconstruction using time-gated wavefront sensing approach [PDF]
Journal of the European Optical Society-Rapid Publications, 2013 In order to estimate the multi-layer surface profile and to detect the inter-layer surfaces defects, gated wavefront sensing approach has been proposed in the previous works [1, 2].
Tan C. S. +4 more
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Reference Wave Design for Wavefront Sensing [PDF]
2021 IEEE International Conference on Computational Photography (ICCP), 2021 One of the classical results in wavefront sensing is phase-shifting point diffraction interferometry (PS-PDI), where the phase of a wavefront is measured by interfering it with a planar reference created from the incident wave itself. The limiting drawback of this approach is that the planar reference, often created by passing light through a narrow ...
Wei-Yu Chen +3 more
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Near-infrared wavefront sensing [PDF]
SPIE Proceedings, 2016 We discuss the advantages of wavefront sensing at near-infrared (IR) wavelengths with low-noise detector technologies that have recently become available. In this paper, we consider low order sensing with laser guide star (LGS) adaptive optics (AO) and high order sensing with natural guide star (NGS) AO.
Wizinowich, Peter +10 more
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Wavefront sensing with critical sampling [PDF]
Optics Letters, 2011 Different types of nonredundant sampling patterns are shown to guarantee completeness of the basis formed by the sampled partial derivatives of Zernike polynomials, commonly used to reconstruct the wavefront from its slopes (wavefront sensing). In the ideal noise-free case, this enables one to recover double the number of modes J than sampling points I
Navarro, Rafael +2 more
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A Tip–Tilt and Piston Detection Approach for Segmented Telescopes
Photonics, 2020 Accurate segmented mirror wavefront sensing and control is essential for next-generation large aperture telescope system design. In this paper, a direct tip–tilt and piston error detection technique based on model-based phase retrieval with multiple ...
Shun Qin, Wai Kin Chan
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Digging Deeper through Biological Specimens Using Adaptive Optics-Based Optical Microscopy
Photonics, 2023 Optical microscopy is a vital tool for visualizing the cellular and sub-cellular structures of biological specimens. However, due to its limited penetration depth, its biological applicability has been hindered.
Gagan Raju, Nirmal Mazumder
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Wavefront measurement method based on improved light field camera
Results in Physics, 2020 The light field camera is used in the wavefront sensing field because of its simple structure, large field of view, high utilization rate of light energy, etc.
Xin Chen +7 more
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Beam wavefront retrieval by convoluted spatial spectral benchmark
Matter and Radiation at Extremes, 2021 We propose a method for retrieving a beam wavefront from its near-field intensity distribution after a 4f system by simply inserting a benchmark at the Fourier plane.
Xuewei Deng +5 more
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Calibration and performance evaluation of a monomorph deformable mirror
Results in Optics, 2022 To achieve diffraction-limited performance with a 50 cm solar telescope at the Udaipur solar observatory the development of a high-order adaptive optics (AO) system is currently in progress. The system includes a monomorph deformable mirror (MDM) with 85
A. Raja Bayanna +3 more
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