Results 61 to 70 of about 2,392,408 (295)

Adaptive wavefront shaping for flow-field measurements

SPIE Proceedings, 2016
In this contribution we use wavefront shaping approaches for image correlation based flow-field measurements for the first time. Aberrations introduced by a single phase boundary in the detection beam path were explored. Variations of the optical path-length result in strong errors in position allocation and thus to an enhancement of the measurement ...
Koukourakis, N., Fregin, B., Büttner, L., Czarske, J. W.   +3 more
openaire   +3 more sources

Terahertz wavefront measurement with a Hartmann sensor

, 2012
The measurement of the wavefront of a terahertz (THz) beam is essential for the development of any optical instrument operating at THz frequencies. We have realized a Hartmann wavefront sensor for the THz frequency range.
Grahn, Holger-T., H. Richter, Pfund, Johannes, Hey, Robert, M. Greiner-Bär, Wienold, Martin, Greiner-Bär, Michael, J. Pfund, Deßmann, Nils, Richter, Heiko, Schrottke, Lutz, Hübers, Heinz-Wilhelm, H.-W. Hübers, M. Wienold, L. Schrottke, H. T. Grahn, R. Hey, N. Deßmann   +17 more
core   +1 more source

Programmable Pneumatic Actuator System for a Bioinspired Artificial Colon

Advanced Materials Technologies, EarlyView.
A modular soft robotic colon simulator driven by programmable pneumatic actuation is developed to mimic physiological and pathological‐like motility patterns of the large intestine. Finite element–guided design and distributed control enable anatomically realistic deformation for peristalsis, segmentation, and mass movements, supporting capsule ...
Andrew Bickerdike, Bo Tian, Xizheng Fang, Zepeng Wang, Yang Liu, Lucy Adams, Shyam Prasad   +6 more
wiley   +1 more source

Aspherical Surface Wavefront Testing Based on Multi-Directional Orthogonal Lateral Shearing Interferometry

Sensors
To overcome the limitations of phase sampling points in testing aspherical surface wavefronts using traditional interferometers, we propose a high-spatial-resolution method based on multi-directional orthogonal lateral shearing interferometry.
Yahui Zhu, Ailing Tian, Hongjun Wang, Bingcai Liu   +3 more
doaj   +1 more source

Liquid‐Crystal‐Based Reconfigurable Intelligent Surface for 7 GHz Mobile Communication

Advanced Materials Technologies, EarlyView.
The glass‐based liquid‐crystal reconfigurable intelligent surface (LC‐RIS) integrates active‐matrix driving and blind‐greedy phase optimization within a 5G‐NR OFDM framework. This enables continuously tunable and autonomous enhancement of wireless coverage. Leveraging the transparency and manufacturability of liquid crystal panels, it is ideally suited
Tien‐Lun Ting, Yuh‐Chyi Chang, Yi‐Chan Hung, Cheng‐Yuan Hsiao, Chao‐Kai Wen, Tsung‐Hsien Lin   +5 more
wiley   +1 more source

Monte Carlo simulation of interferometric measurement and wavefront shaping under influence of shot noise and camera noise

JPhys Photonics
Interferometry often serves as an essential building block of wavefront shaping systems to obtain optimal wavefront solutions. In this tutorial, we provide a Monte Carlo simulation tool to calculate the accuracy of interferometric measurements and its ...
Chunghyeong Lee, Jaeyeon Oh, Hakseok Ko, Mooseok Jang   +3 more
doaj   +1 more source

Variability of wavefront aberration measurements in small pupil sizes using a clinical Shack-Hartmann aberrometer

BMC Ophthalmology, 2004
Background Recently, instruments for the measurement of wavefront aberration in the living human eye have been widely available for clinical applications.
Pallikaris Aristophanis, Plainis Sotiris, Ginis Harilaos S   +2 more
doaj   +1 more source

On‐Chip Photonic Neural Network Architectures

Advanced Optical Materials, EarlyView.
This review presents a comprehensive overview of on‐chip photonic neural network architectures, covering key photonic building blocks, representative network types, and emerging applications. Recent advances, implementation challenges, and future directions are examined, highlighting the potential of integrated photonics to enable ultrafast, energy ...
Seokjin Hong, Berkay Neseli, Seungyeon Cho, Seungsoo Lee, Yeonjun Kim, Seungyoon Choi, Hyo‐Hoon Park, Hamza Kurt   +7 more
wiley   +1 more source

Enhancement of Circular Dichroism in Chiral Dielectric Metasurfaces by Ion Beam Irradiation

Advanced Optical Materials, EarlyView.
Ion beam irradiation enables post fabrication tuning of dissipative losses in chiral dielectric metasurfaces composed of C4 symmetric silicon nanostructures. By tailoring the absorption toward critical coupling condition, circular dichroism is enhanced from 0.70 to 0.85, demonstrating a versatile route for maximizing optical chirality and polarization ...
Anna Fitriana, Katsuya Tanaka, Lukas Raam Jaeger, Martin Hafermann, Thomas Pertsch, Carsten Ronning, Isabelle Staude   +6 more
wiley   +1 more source

Research on Nanometer Precision Measurement Method of High Order Even Aspheres

Applied Sciences
Optical aspheres are demanded with extremely high precision to meet functional requirements in space telescopes, extreme ultraviolet lithography, and other modern large optical systems.
Hao Xu, Junfeng Liu, Shanyong Chen
doaj   +1 more source