Results 31 to 40 of about 8,993 (261)

Double-edge scan wavefront metrology and its application in crystal diffraction wavefront measurements

Journal of Synchrotron Radiation
Achieving diffraction-limited performance in fourth-generation synchrotron radiation sources demands monochromator crystals that can preserve the wavefront across an unprecedented extensive range.
Fang Liu, Ming Li, Qianshun Diao, Zhe Li, Zhibang Shen, Fan Li, Zhen Hong, Hongkai Lian, Shuaipeng Yue, Qingyan Hou, Changrui Zhang, Dongni Zhang, Congcong Li, Fugui Yang, Junliang Yang   +14 more
doaj   +1 more source

Surface Measurement Using Compressed Wavefront Sensing

Photonic Sensors, 2018
Compressed sensing leverages the sparsity of signals to reduce the amount of measurements required for its reconstruction. The Shack-Hartmann wavefront sensor meanwhile is a flexible sensor where its sensitivity and dynamic range can be adjusted based on
Eddy Mun Tik Chow, Ningqun Guo, Edwin Chong, Xin Wang   +3 more
doaj   +1 more source

Research on Optical Metrology for Complex Optical Surfaces with Focal Plane Wavefront Sensing

Micromachines, 2023
Complex optical elements have the advantages of improving image quality and optical performance and expanding the field of view. Therefore, it is widely used in X-ray scientific devices, adaptive optical elements, high-energy laser systems, and other ...
Xinxue Ma, Jianli Wang, Bin Wang, Xinyue Liu, Yuqiang Chen   +4 more
doaj   +1 more source

Enhanced Ultrasound Transmission Through Aberration Layers Using Space‐Coiling Acoustic Metamaterials

Advanced Engineering Materials, EarlyView.
Enhancing ultrasound transmission through an aberration layer exhibiting mismatched impedance with the surrounding medium possesses great implications in imaging and treatment. In this study, we show that a space‐coiling acoustic metamaterial with judiciously tailored structural profile can help improve impedance matching.
Maral Ghanami, Hengzhe Ren, Erqian Dong, Ashkan Ghanbarzadeh‐Dagheyan, Chen Shen   +4 more
wiley   +1 more source

Experimental Investigation of Pixelated Instantaneous Phase-Shifting Interferometry Using Liquid Crystal Spatial Light Modulator

Photonics
A pixelated instantaneous phase-shifting interferometry (PSI) using a phase-only liquid crystal spatial light modulator (LC-SLM) is developed and experimentally validated.
Fuzhong Bai, Zhiwen Zhao, Jiayi Chen, Xiaojuan Gao, Yubo Chang, Jianxin Wang, Jixiang Cai   +6 more
doaj   +1 more source

Field Deviation in Radiated Emission Measurement in Anechoic Chamber for Frequencies up to 60 GHz and Deep Learning-Based Correction

International Journal of Antennas and Propagation, 2022
The measurement of radiated emission (RE) in an anechoic chamber becomes very challenging at high frequencies, up to 60 GHz, because the scanning plane of the receiver is in measurement standard deviation from the actual wavefront.
Feng Shi, Liping Yan, Xuping Yang, Xiang Zhao, Richard Xian-Ke Gao   +4 more
doaj   +1 more source

Hartmann wavefront measurements at FLASH [PDF]

SPIE Proceedings, 2013
Published by SPIE, Bellingham, Wash.
Keitel, Barbara, Floeter, Bernhard, Kreis, Svea, Kuhlmann, Marion, Mann, Klaus, Mey, Tobias, Plönjes, Elke, Schaefer, Bernd, Tiedtke, Kai   +8 more
openaire   +2 more sources

Chiral Phase Change Nanomaterials

Advanced Functional Materials, EarlyView.
This work demonstrates reversible, non‐volatile phase transitions in chiral Ge2${\rm Ge}_2$Sb2${\rm Sb}_2$Te5${\rm Te}_5$ (GST) nanohelices for high‐speed optical modulation of chirality and dynamic control of the state of polarization (SOP). The chiral nanostructures are fabricated using a highly directional, wafer‐scale physical vapor deposition ...
Joshua A. Burrow, Md Shah Alam, Riad Yahiaoui, Evan M. Smith, Ryan Laing, Jules Gardener, Thomas A. Searles, Piyush J. Shah, Shivashankar Vangala, Joshua R. Hendrickson, Andrew M. Sarangan, Imad Agha   +11 more
wiley   +1 more source

Accuracy characterization of Shack–Hartmann sensor with residual error removal in spherical wavefront calibration

Light: Advanced Manufacturing
The widely used Shack–Hartmann wavefront sensor (SHWFS) is a wavefront measurement system. Its measurement accuracy is limited by the reference wavefront used for calibration and also by various residual errors of the sensor itself.
Yi He, Mingdi Bao, Yiwei Chen, Hong Ye, Jinyu Fan, Guohua Shi   +5 more
doaj   +1 more source

From Photoalignment to Structured Light: Liquid Crystal Platforms for Beam Shaping and Complex Wavefronts

Advanced Functional Materials, EarlyView.
Photoaligned and photopatterned liquid crystal platforms provide programmable control of optical phase, polarization, and spin‐orbit interactions, enabling compact generation of structured light and complex wavefronts. This review highlights how tailored molecular orientations transform simple beams into designed optical fields, opening versatile ...
Le Zhou, Tingjun Zhong, Sijie Liu, Pouya Nosratkhah, Ke Xu, Yuzhen Zhao, Kristiaan Neyts   +6 more
wiley   +1 more source