Results 231 to 240 of about 8,969 (258)
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Measurements of the Isoplanatic Angle of the Wavefront Tilt
Adaptive Optics, 1996Investigating the tilt correlation as a function of separation angle, exposure time and aperture, the maximum angular distance between the object and the tip-tilt guide star is determined. This distance can be increased by multiple guide stars.
Thomas Berkefeld, Andreas Glindemann
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Wavefront measurement by using photonic crystals
SPIE Proceedings, 2004This paper presents a novel method of wavefront measurement for adaptive optic systems by using a photonic crystal. In adaptive optics the wavefront shape of the incident wave is measured and used to set a reconfigurable mirror array to compensate for the aberration, reduce distortion and improve image and beam quality.
Hua Tong, Alastair D. McAulay
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Repeatability of wavefront measurements in pseudophakic eyes
Spektrum der Augenheilkunde, 2019Higher- as well as lower-order aberrations influence uncorrected visual quality after successful cataract surgery. Different techniques are used for measuring ocular wavefront aberrations, such as Hartmann–Shack aberrometers, laser ray tracing aberrometers, and automatic retinoscopy.
Christoph Leisser +3 more
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Parameters for Wavefront Sensor Measurement
2010Wavefronts cannot be perceived because it is light intensity rather than phase that interacts directly with matter. Detectors such as our eye respond to brightness levels, not differences in optical path length. Detectors in wavefront sensors also respond to light level. However, this response is related to some kind of length measurement. This chapter
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Wavefront phase measurement by optical differentiation
Annual Meeting Optical Society of America, 1988A hybrid optical–digital processor employs the Fourier differentiation theorem to compute the 2-D gradient of wavefront slopes. By means of a coherent optical processor with linearly varying amplitude transmittance in the Fourier-transform plane1 and a 2-D detector array in the output plane, an intensity image is produced which contains the derivatives
G. J. W. Aitken, P. F. Jones
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Issues of wavefront tilt measurement
Journal of Optical Technology, 2021L. A. Bol’basova, V. P. Lukin
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Wavefront Sensor in Measurements of MEMS Vibrations
2019The paper discusses an application of Shack-Hartmann wavefront sensor with stroboscopic illumination for measurements of the vibration modes at resonance frequencies of a MEMS devices. The wavefront sensor estimates the local slopes of the wavefront by measuring the displacement of light spots created by microlens array on the camera plane. The goal of
Michał Józwik, Dinesh Raja Nagarajan
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Robust and accurate measurement of optical freeform surfaces with wavefront deformation correction
Optics Express, 2022Haoyu Lyu +2 more
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DCT single-pixel detecting for wavefront measurement
Optics and Laser Technology, 2023Aiping Zhai
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