Results 21 to 30 of about 1,288 (199)

Investigation of extended depth-of-field f/8 camera with optimized cubic phase mask and digital restoration [PDF]

EPJ Web of Conferences, 2020
An investigation of extended depth-of-field camera with optimized phase mask and digital restoration is presented. The goal of this paper is to implement the wavefront coding technique without affecting much of the original design, and the design has ...
Chiu Po-Sheng, Vonmetz Kurt, Canini Federico, Urbach H. Paul   +3 more
doaj   +1 more source

Curvature Sensing-Based Pupil Alignment Method for Large-Aperture Telescopes

IEEE Photonics Journal, 2023
In optical systems, pupil alignment is an important component of wavefront sensing, closed-loop feedback, and imaging vignetting control because it directly affects the detection limit of the system and thus the realization of scientific goals.
Qichang An, Hanfu Zhang, Xiaoxia Wu, Jianli Wang, Tao Chen, Guohao Ju   +5 more
doaj   +1 more source

Microscope with extension of the depth of field by employing a cubic phase plate on the surface of lens

Results in Optics, 2021
An incoherent optical system with wavefront coding extends the depth of field (DOF) by employing a cubic phase plate (CPP). We designed a digital microscope with a CPP in the aperture stop and on the surface of the lens, which extended the DOF.
Chi-Feng Lee, Cheng-Chung Lee
doaj   +1 more source

Secure communication with coded wavefronts

2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2017
Communication between a sender and receiver can be made secure by encrypting the message using public or private shared keys. Quantum key distribution utilizes the unclonability of a quantum state to securely generate a key between the two parties [1]. However, without some way of authentication of either the sender or the receiver, a man-in-the-middle
Uppu, Ravitej, Wolterink, Tom A.W., Goorden, Sebastianus A., Sˇkoric´, Boris, Mosk, Allard P., Pinkse, Pepijn W.H.   +5 more
openaire   +3 more sources

A review of liquid crystal spatial light modulators: devices and applications

Opto-Electronic Science, 2023
Spatial light modulators, as dynamic flat-panel optical devices, have witnessed rapid development over the past two decades, concomitant with the advancements in micro- and opto-electronic integration technology.
Yiqian Yang, Andrew Forbes, Liangcai Cao
doaj   +1 more source

Convolution operations on time-domain digital coding metasurface for beam manipulations of harmonics

Nanophotonics, 2020
Time-domain digital coding metasurfaces have been proposed recently to achieve efficient frequency conversion and harmonic control simultaneously; they show considerable potential for a broad range of electromagnetic applications such as wireless ...
Zhang Cheng, Yang Jin, Yang Liu Xi, Ke Jun Chen, Chen Ming Zheng, Cao Wen Kang, Chen Mao, Wu Zhan Hao, Chen Jian Feng, Cheng Qiang, Cui Tie Jun   +10 more
doaj   +1 more source

Acoustic Focusing with Intensity Modulation Based on Sub-Wavelength Waveguide Array

Crystals, 2021
Acoustic focusing with intensity modulation plays an important role in biomedical and life sciences. In this work, we propose a new approach for simultaneous phase and amplitude manipulation in sub-wavelength coupled resonant units, which has not been ...
Mingran Zhang, Guangrui Gu
doaj   +1 more source

Ultra-high resolution coded wavefront sensor

Optics Express, 2017
Wavefront sensors and more general phase retrieval methods have recently attracted a lot of attention in a host of application domains, ranging from astronomy to scientific imaging and microscopy. In this paper, we introduce a new class of sensor, the Coded Wavefront Sensor, which provides high spatio-temporal resolution using a simple masked sensor ...
Wang, Congli, Dun, Xiong, Fu, Qiang, Heidrich, Wolfgang   +3 more
openaire   +3 more sources

Test of the Practicality and Feasibility of EDoF-Empowered Image Sensors for Long-Range Biometrics

Sensors, 2016
For many practical applications of image sensors, how to extend the depth-of-field (DoF) is an important research topic; if successfully implemented, it could be beneficial in various applications, from photography to biometrics. In this work, we want to
Sheng-Hsun Hsieh, Yung-Hui Li, Chung-Hao Tien   +2 more
doaj   +1 more source

Broadband photon sieves imaging with wavefront coding

Optics Express, 2015
A novel method for broadband imaging of using a diffractive photon sieves is proposed and experimentally demonstrated. Unlike conventional photon sieves imaging in which clear imaging is only valid at a single designed wavelength due to the strong wavelength-dependent nature of diffractive elements, broadband photon sieves imaging is implemented with ...
Xiaonan, Zhao, Feng, Xu, Jingpei, Hu, Chinhua, Wang   +3 more
openaire   +2 more sources