English
Related papers

Related papers: Optimizing the performance of an Astigmatic Defocu…

200 papers

This study introduces a novel data-centric approach to improve real-time surgical guidance using fiber-based fluorescence lifetime imaging (FLIm). A key aspect of the methodology is the accurate detection of the aiming beam, which is…

Artificial Intelligence · Computer Science 2024-11-13 Mohamed Abul Hassan , Pu Sun , Xiangnan Zhou , Lisanne Kraft , Kelsey T Hadfield , Katjana Ehrlich , Jinyi Qi , Andrew Birkeland , Laura Marcu

Computer-generated holograms (CGHs) are used in holographic three-dimensional (3D) displays and holographic projections. The quality of the reconstructed images using phase-only CGHs is degraded because the amplitude of the reconstructed…

Computer Vision and Pattern Recognition · Computer Science 2022-02-02 Yoshiyuki Ishii , Tomoyoshi Shimobaba , David Blinder , Tobias Birnbaum , Peter Schelkens , Takashi Kakue , Tomoyoshi Ito

We report a demonstration of laser Doppler holography at a sustained acquisition rate of 250 Hz on a 1 Megapixel complementary metal-oxide-semiconductor (CMOS) sensor array and image display at 10 Hz frame rate. The holograms are optically…

Optics · Physics 2015-06-12 Benjamin Samson , Michael Atlan

We propose an autofocusing algorithm to obtain, relatively accurately, the 3D position of each particle, particularly its axial location, and particle number of a dense transparent particle solution via its hologram. First, morphological…

Signal Processing · Electrical Eng. & Systems 2025-03-25 Wei-Na Li , Yi Zhou , Jiatai Chen , Hongjie Ou , XiangSheng Xie

The capability of focus control has been central to optical technologies that require both high temporal and spatial resolutions. However, existing varifocal lens schemes are commonly limited to the response time on the microsecond…

A survey of acoustic devices for focusing airborne sound is presented. We introduce a new approach to design high quality acoustic lenses based on arrays of cylindrical rigid scatterers in air. A population based stochastic search algorithm…

Materials Science · Physics 2007-05-23 Andreas Hakansson , Jose Sanchiz-Dehesa , Lorenzo Sanchis

In low-visibility marine environments characterized by turbidity and darkness, acoustic cameras serve as visual sensors capable of generating high-resolution 2D sonar images. However, acoustic camera images are interfered with by complex…

Computer Vision and Pattern Recognition · Computer Science 2024-06-06 Xiaoteng Zhou , Katsunori Mizuno , Yilong Zhang

Aberration-corrected Scanning Transmission Electron Microscopy (STEM) has become an essential tool in understanding materials at the atomic scale. However, tuning the aberration corrector to produce a sub-{\AA}ngstr\"om probe is a complex…

We report 3D-printed acoustic holographic lenses for the formation of ultrasonic fields of complex spatial distribution inside the skull. Using holographic lenses, we experimentally, numerically and theoretically produce acoustic beams…

Gratings and holograms are patterned surfaces that tailor optical signals by diffraction. Despite their long history, variants with remarkable functionalities continue to be discovered. Further advances could exploit Fourier optics, which…

A unique sample independent 3D self calibration methodology is tested on a unique optical coherence tomography and multi-spectral scanning laser ophthalmoscope (OCT-SLO) hybrid system. Operators visual cognition is replaced by computer…

Medical Physics · Physics 2024-08-08 Mayank Goswami

The visualization of pure phase objects by wavefront sensing has important applications ranging from surface profiling to biomedical microscopy, and generally requires bulky and complicated setups involving optical spatial filtering,…

Optics · Physics 2023-08-29 Jianing Liu , Hao Wang , Yuyu Li , Lei Tian , Roberto Paiella

The rapid advancement of generative AI has enabled the mass production of photorealistic synthetic images, blurring the boundary between authentic and fabricated visual content. This challenge is particularly evident in deepfake scenarios…

Computer Vision and Pattern Recognition · Computer Science 2025-09-30 Minsun Jeon , Simon S. Woo

A photogrammetric method of stress analysis has been developed to test thin, nonstandard windows designed for hydrogen absorbers, major components of a muon cooling channel. The purpose of the absorber window tests is to demonstrate an…

Instrumentation and Detectors · Physics 2008-11-26 Donna L. Kubik , John A. Greenwood

The histogram of oriented gradients (HOG) is a widely used feature descriptor in computer vision for the purpose of object detection. In the paper, a modified HOG descriptor is described, it uses a lookup table and the method of integral…

Computer Vision and Pattern Recognition · Computer Science 2017-03-21 Chunde Huang , Jiaxiang Huang

Multi-focus image fusion is a technique for obtaining an all-in-focus image in which all objects are in focus to extend the limited depth of field (DoF) of an imaging system. Different from traditional RGB-based methods, this paper presents…

Computer Vision and Pattern Recognition · Computer Science 2018-06-06 Hang Liu , Hengyu Li , Jun Luo , Shaorong Xie , Yu Sun

In current paper, distortions in digital demodulation schemes with harmonic phase modulation for interferometric optical sensors are considered. In particular, the influence of target signal variations on phase demodulation errors is…

Instrumentation and Detectors · Physics 2019-05-08 Leonid Liokumovich , Andrei Medvedev , Konstantin Muravyov , Philipp Skliarov , Nikolai Ushakov

Tracking the movement of human eyes is expected to yield natural and convenient applications based on human-computer interaction (HCI). To implement an effective eye-tracking system, eye movements must be recorded without placing any…

Human-Computer Interaction · Computer Science 2016-11-30 Manh Duong Phung , Quang Vinh Tran , Kenji Hara , Hirohito Inagaki , Masanobu Abe

In a previous paper, we discussed an original solution to improve the performances of coronagraphs by adding, in the optical scheme, an adaptive hologram removing most of the residual speckle starlight. In our simulations, the detection…

Instrumentation and Methods for Astrophysics · Physics 2011-02-17 Davide Ricci , Hervé Le Coroller , Antoine Labeyrie , Pierre Piron

Fourier optics, the principle of using Fourier Transformation to understand the functionalities of optical elements, lies at the heart of modern optics, and has been widely applied to optical information processing, imaging, holography etc.…