Results 171 to 180 of about 5,505 (209)
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Shack-Hartmann wavefront sensor - advantages and disadvantages
2010 International Conference on Advanced Optoelectronics and Lasers, 2010In this paper we discuss the ability of Shack-Hartmann wavefront sensor to be used in the closed loop adaptive system. For sure we do not discuss the possibility of wavefront sensor to measure aberrations of laser beam. But at the same time we consider Shack-Hartmann wavefront sensor to be not the best device in any adaptive optical system.
Alexis Kudryashov +4 more
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Detection error of Shack-Hartmann wavefront sensors
SPIE Proceedings, 1997The detecting error of Shack-Hartmann (S-H) sensor is one of the main error sources in adaptive pptical systems. In this paper the main sources of S-H sensor for both of the systematic error and random noise are analyzed. These factors are readout noise and background level of CCD camera, number of detecting pixels, and photon shot noise.
Wenhan Jiang, Hao Xian, Feng Shen
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Shack-Hartmann wavefront sensor precision and accuracy
SPIE Proceedings, 2002The design of a wavefront sensor may be determined by the lenslet array and camera selection. There are numerous different applications for these sensors, requiring widely differing dynamic range and accuracy. Performance metrics are needed to evaluate candidate designs and to compare results.
Daniel R. Neal +2 more
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Wavefront reconstruction for the Shack-Hartmann wavefront sensor
SPIE Proceedings, 2002The Shack-Hartmann wavefront sensor is a powerful tool for optical analysis. A vital step in the data analysis chain involves reconstructing the wavefront incident upon the lenslet array from hundreds or thousands of slope measurements. We discuss here the basics of reconstruction and the differences in reconstruction for the case of Hartmann and Shack-
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Performance analysis of Shack-Hartmann wavefront sensor
SPIE Proceedings, 2008A detailed analysis of the principle of Shack-Hartmann wavefront sensor is presented. Typical performance metrics such as dynamic range, sensitivity, repeatability and accuracy are defined and discussed. A method with which to calibrate a Shack-Hartmann wavefront sensor for absolute wavefront measurement for tilt without any accessorial apparatus is
Hongli Chen, Linhui Chen, Changhui Rao
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Aerosol absorption measurement by a Shack–Hartmann wavefront sensor
Applied Optics, 2023Researchers at the U.S. Army Space and Missile Defense Command have developed a method for quantifying high energy near-infrared (NIR) laser heating of air resulting from laser absorption of suspended dry aerosols in a controlled environmental chamber. The measurements were accomplished using an ISO standard test dust and NIR high energy laser using a ...
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Angular tolerance of Shack-Hartmann wavefront sensors with microaxicons
Optics Letters, 2007Wavefront sensing under nonparaxial conditions was studied with Shack-Hartmann setups based on arrays of microaxicons. The robustness of the generated pseudonondiffracting subbeams against tilt and axial displacement was demonstrated for ultraflat Gaussian- and inverse-Gaussian-shaped elements in transmission and reflection.
Ruediger, Grunwald +4 more
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Shack-Hartmann wavefront sensor with holographic memory
Optical Engineering, 2003A Shack-Hartmann wavefront sensor with a dual-focus holographic lenslet array and a known wavefront distortion is introduced. It enables measurement of a small phase distortion in optical waves under significant background wavefront aberrations and extending its angular dynamic range.
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Optical path difference microscopy with a Shack–Hartmann wavefront sensor
Optics Letters, 2017In this Letter, we show that a Shack-Hartmann wavefront sensor can be used for the quantitative measurement of the specimen optical path difference (OPD) in an ordinary incoherent optical microscope, if the spatial coherence of the illumination light in the plane of the specimen is larger than the microscope resolution.
Hai Gong +5 more
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Improved wavefront reconstruction algorithm for Shack–Hartmann type wavefront sensors
Journal of Optics, 2014In the present work, we propose an improved wavefront reconstruction algorithm for zonal wavefront estimation using Shack–Hartmann type wavefront sensors. We start with the well known W H Southwell reconstruction algorithm, where phase at a central point is described in terms of horizontal and vertical slope values.
Biswajit Pathak, Bosanta R Boruah
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