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Most camera lens systems are designed in isolation, separately from downstream computer vision methods. Recently, joint optimization approaches that design lenses alongside other components of the image acquisition and processing pipeline…

Computer Vision and Pattern Recognition · Computer Science 2023-03-29 Geoffroi Côté , Fahim Mannan , Simon Thibault , Jean-François Lalonde , Felix Heide

Ptychography is a lensless, computational imaging method that utilises diffraction patterns to determine the amplitude and phase of an object. In transmission ptychography, the diffraction patterns are recorded by a detector positioned…

Image and Video Processing · Electrical Eng. & Systems 2023-01-04 Kira A. M. Maathuis , Jacob Seifert , Allard P. Mosk

We report a novel method to generate arbitrary optical focus arrays (OFAs). Our approach rapidly produces computer-generated holograms (CGHs) to precisely control the positions and the intensities of the foci. This is achieved by replacing…

Optics · Physics 2024-10-24 Xin Liu , Yiwen Hu , Shijie Tu , Cuifang Kuang , Xu Liu , Xiang Hao

We introduce ergonomic-centric holography, an algorithmic framework that simultaneously optimizes for realistic incoherent defocus, unrestricted pupil movements in the eye box, and high-order diffractions for filtering-free holography. The…

Graphics · Computer Science 2023-06-21 Liang Shi , DongHun Ryu , Wojciech Matusik

We present a method that takes as input a single dual-pixel image, and simultaneously estimates the image's defocus map -- the amount of defocus blur at each pixel -- and recovers an all-in-focus image. Our method is inspired from recent…

Computer Vision and Pattern Recognition · Computer Science 2021-10-13 Shumian Xin , Neal Wadhwa , Tianfan Xue , Jonathan T. Barron , Pratul P. Srinivasan , Jiawen Chen , Ioannis Gkioulekas , Rahul Garg

A Deformable Mirror (DM) is an important component of an Adaptive Optics system. It is known that an on-axis spherical/parabolic optical component, placed at an angle to the incident beam introduces defocus as well as astigmatism in the…

Techniques like speckle holography and shearography are rarely applied due to the complexity of instrument setup and lack of automated result analysis, despite their potential. By simulating speckle interferometric outcomes, we seek to…

Optics · Physics 2025-11-25 Jessica Plassmann , Michael Schuth , Georg von Freymann

In this paper we apply digital in-line holography to image opaque objects through a thick plano-concave pipe. Opaque fibers and opaque particles are considered}. Analytical expression of the intensity distribution in the CCD sensor plane is…

Optics · Physics 2012-12-21 Nicolas Verrier , Coëtmellec Sébastien , Brunel Marc , Lebrun Denis

Angular filter refractometry is an optical diagnostic that measures absolute contours of line-integrated density gradient by placing a filter with alternating opaque and transparent zones in the focal plane of a probe beam, which produce…

Plasma Physics · Physics 2023-11-30 P. V. Heuer , D. Haberberger , S. T. Ivancic , C. A. Walsh , J. R. Davies

Dehazing is in the image processing and computer vision communities, the task of enhancing the image taken in foggy conditions. To better understand this type of algorithm, we present in this document a dehazing method which is suitable for…

Computer Vision and Pattern Recognition · Computer Science 2020-06-02 Bangyong Sun , Vincent Whannou de Dravo , Zhe Yu

For distant iris recognition, a long focal length lens is generally used to ensure the resolution ofiris images, which reduces the depth of field and leads to potential defocus blur. To accommodate users at different distances, it is…

Computer Vision and Pattern Recognition · Computer Science 2021-06-30 Leyuan Wang , Kunbo Zhang , Yunlong Wang , Zhenan Sun

Automation in optical microscopy is critical for enabling high-throughput imaging across a wide range of biomedical applications. Among the essential components of automated systems, robust autofocusing plays a pivotal role in maintaining…

Image denoising stands as a critical challenge in image processing and computer vision, aiming to restore the original image from noise-affected versions caused by various intrinsic and extrinsic factors. This process is essential for…

Image and Video Processing · Electrical Eng. & Systems 2024-03-19 Peter Luvton , Alfredo Castillejos , Jim Zhao , Christina Chajo

We introduce and experimentally implement Fourier-plane phase synchronization for optical microscopy, and demonstrate its performance with interferometric scattering microscopy. By combining a photothermal phase plate and laser beam…

Image defogging is a technique used extensively for enhancing visual quality of images in bad weather condition. Even though defogging algorithms have been well studied, defogging performance is degraded by demosaicking artifacts and sensor…

Computer Vision and Pattern Recognition · Computer Science 2017-05-24 Y. J. Lee , K. Hirakawa , T. Q. Nguyen

Holographic displays promise several benefits including high quality 3D imagery, accurate accommodation cues, and compact form-factors. However, holography relies on coherent illumination which can create undesirable speckle noise in the…

Graphics · Computer Science 2023-09-20 Grace Kuo , Florian Schiffers , Douglas Lanman , Oliver Cossairt , Nathan Matsuda

Acoustic holographic lenses, also known as acoustic holograms, can change the phase of a transmitted wavefront in order to shape and construct complex ultrasound pressure fields, often for focusing the acoustic energy on a target region.…

We investigate data-aided iterative sensing in bistatic OFDM ISAC systems, focusing on scenarios with co-located sensing and communication receivers. To enhance target detection beyond pilot-only sensing methods, we propose a multi-stage…

Signal Processing · Electrical Eng. & Systems 2025-05-05 Musa Furkan Keskin , Silvia Mura , Marouan Mizmizi , Dario Tagliaferri , Henk Wymeersch

Aiming at realizing novel vision augmentation experiences, this paper proposes the IlluminatedFocus technique, which spatially defocuses real-world appearances regardless of the distance from the user's eyes to observed real objects. With…

Human-Computer Interaction · Computer Science 2020-03-10 Tatsuyuki Ueda , Daisuke Iwai , Takefumi Hiraki , Kosuke Sato

Usually, off-axis digital holographic microscopy requires a coherent light source in order to record a full-field hologram. Nevertheless, a LASER-based illumination leads to a non-negligible coherent noise, decreasing then the imaging…

Optics · Physics 2021-11-02 Stephane Perrin , Jonas Kuhn , Christian Depeursinge