Results 21 to 30 of about 8,993 (261)

Calibrating CGH Substrate TWE and Simulating Adjustment Error in Cylindrical Surface Measurement

open access: yesIEEE Photonics Journal, 2022
Computer-generated hologram (CGH) is a diffractive optical element that has been commonly used as wavefront corrector in the interferometer and can be accurately manufactured to meet the requirements of high-precision detection.
Linghua Zhang   +5 more
doaj   +1 more source

Fast holographic scattering compensation for deep tissue biological imaging

open access: yesNature Communications, 2021
Wavefront shaping is used to overcome scattering in biological tissues during imaging, but determining the compensation is slow. Here, the authors use holographic phase stepping interferometry, where new phase information is updated after each ...
Molly A. May   +5 more
doaj   +1 more source

Method for distortion correction of multi-layered surface reconstruction using time-gated wavefront sensing approach [PDF]

open access: yesJournal 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
doaj   +1 more source

Adaptive particle image velocimetry based on sharpness metrics

open access: yesJournal of the European Optical Society-Rapid Publications, 2018
Background Optical distortions can significantly deteriorate the measurement accuracy in particle image velocimetry systems. Such distortions can occur at fluctuating phase boundaries during flow measurement and result from the accompanied refractive ...
M. Teich   +4 more
doaj   +1 more source

Simulation Analysis of a Wavefront Reconstruction of a Large Aperture Laser Beam

open access: yesSensors, 2023
In order to solve the problem of atmospheric influence on the far-field measurement of the quality of a laser beam, we proposed a direct wavefront measurement system based on the Hartmann detection principle, which can measure large apertures and high ...
Gangyu Wang   +4 more
doaj   +1 more source

Performance Characterization of Deep-Phase-Retrieval Shack-Hartmann Wavefront Sensors

open access: yesIEEE Photonics Journal, 2023
Shack-Hartmann wavefront sensor (SHWFS) is the most popular wavefront sensor in adaptive optics systems. The Deep-Phase-Retrieval Wavefront Reconstruction (DPRWR) method, which was proposed by our group previously, is a kind of deep learning-based ...
Manting Zhang, Youming Guo
doaj   +1 more source

Simultaneous quantification of longitudinal and transverse ocular chromatic aberrations with Hartmann–Shack wavefront sensor [PDF]

open access: yesJournal of Innovative Optical Health Sciences, 2018
A simple method to objectively and simultaneously measure eye’s longitudinal and transverse chromatic aberrations was proposed. A dual-wavelength wavefront measurement system using two Hartmann–Shack wavefront sensors was developed. The wavefronts of the
Yangchun Deng   +3 more
doaj   +1 more source

Quantitative X-ray Channel-Cut Crystal Diffraction Wavefront Metrology Using the Speckle Scanning Technique

open access: yesSensors, 2020
A speckle-based method for the X-ray crystal diffraction wavefront measurement is implemented, and the slope errors of channel-cut crystals with different surface characteristics are measured.
Lian Xue   +5 more
doaj   +1 more source

Deep Tissue Wavefront Estimation for Sensorless Aberration Correction

open access: yesMATEC Web of Conferences, 2015
The multiple light scattering in biological tissues limits the measurement depth for traditional wavefront sensor. The attenuated ballistic light and the background noise caused by the diffuse light give low signal to noise ratio for wavefront ...
Ibrahimovic Emina   +4 more
doaj   +1 more source

Interferometric Wavefront Sensing System Based on Deep Learning

open access: yesApplied Sciences, 2020
At present, most wavefront sensing methods analyze the wavefront aberration from light intensity images taken in dark environments. However, in general conditions, these methods are limited due to the interference of various external light sources.
Yuhao Niu   +4 more
doaj   +1 more source

Home - About - Disclaimer - Privacy