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The development of the semiconductor quantum cascade laser (QCL) [1] has enabled bright coherent sources operating at frequencies between the optical (>100 THz) and electronic (<0.5 THz) ranges opening this frequency region for fundamental…

Lensless microscopy with coherent or partially coherent light sources is a well known imaging technique, commonly referred as digital in-line holographic microscopy. In the established methods, both the spatial and temporal coherence of…

Optics · Physics 2020-11-04 Sanjeev Kumar , Manjunatha Mahadevappa , Pranab Kumar Dutta

In this article, we provide an alternative up-sampling and PSF deconvolution method for the iterative multi-exposure coaddition. Different from the previous works, the new method has a ratio-correction term, which allows the iterations to…

Instrumentation and Methods for Astrophysics · Physics 2022-10-26 Lei Wang , Guoliang Li , Xi Kang

Multi-photon microscopy is a powerful technique for deep-tissue imaging, providing high spatial resolution at increased penetration depth. Nevertheless, imaging remains largely restricted to superficial tissue layers well below 1 mm.…

Decreased visibility, intensive noise, and biased color are the common problems existing in low-light images. These visual disturbances further reduce the performance of high-level vision tasks, such as object detection, and tracking. To…

Computer Vision and Pattern Recognition · Computer Science 2023-06-30 Hao Chen , Zhi Jin

Magnetic Particle Imaging (MPI) is an emerging imaging modality that maps the spatial distribution of magnetic nanoparticles. The x-space reconstruction in MPI results in highly blurry images, where the resolution depends on both system…

Medical Physics · Physics 2020-01-31 Onur Yorulmaz , Omer Burak Demirel , Yavuz Muslu , Tolga Çukur , Emine U Saritas , A Enis Çetin

In this paper we present a blind deconvolution scheme based on statistical wavelet estimation. We assume no prior knowledge of the wavelet, and do not select a reflector from the signal. Instead, the wavelet (ultrasound pulse) is…

Other Computer Science · Computer Science 2015-06-01 Roberto H. Herrera , Zhaorui Liu , Natasha Raffa , Paul Christensen , Adrianus Elvers

High-performance multimode/multiwavelength (de)multiplexer is one of the most pivotal photonic devices for advanced on-chip interconnect systems. Traditional on-chip photonic (de)multiplexing requires large device footprint for maintaining…

Optics · Physics 2025-09-03 Faqian Chong , Yulun Wu , Bingtao Gao , Shilong Li , Hongsheng Chen , Song Han

Complete removal of cancer tumors with a negative specimen margin during lumpectomy is essential in reducing breast cancer recurrence. However, 2D specimen radiography (SR), the current method used to assess intraoperative specimen margin…

Computer Vision and Pattern Recognition · Computer Science 2025-06-27 Tyler Ward , Xiaoqin Wang , Braxton McFarland , Md Atik Ahamed , Sahar Nozad , Talal Arshad , Hafsa Nebbache , Jin Chen , Abdullah Imran

For conventional computed tomography (CT) image reconstruction tasks, the most popular method is the so-called filtered-back-projection (FBP) algorithm. In it, the acquired Radon projections are usually filtered first by a ramp kernel…

Medical Physics · Physics 2018-07-06 Yongshuai Ge , Qiyang Zhang , Zhanli Hu , Jianwei Chen , Wei Shi , Hairong Zheng , Dong Liang

Smoothed phase-coded frequency modulated continuous waveform (SPC-FMCW), which is aimed to improve the coexistence of multiple radars operating within the same frequency bandwidth, is studied, and the receiving strategy with a low ADC…

Signal Processing · Electrical Eng. & Systems 2023-01-26 Utku Kumbul , Nikita Petrov , Cicero S. Vaucher , Alexander Yarovoy

Recent learning-based lossless image compression methods encode an image in the unit of subimages and achieve comparable performances to conventional non-learning algorithms. However, these methods do not consider the performance drop in…

Image and Video Processing · Electrical Eng. & Systems 2021-12-14 Hochang Rhee , Yeong Il Jang , Seyun Kim , Nam Ik Cho

Reproducing an all-in-focus image from an image with defocus regions is of practical value in many applications, eg, digital photography, and robotics. Using the output of some existing defocus map estimator, existing approaches first…

Computer Vision and Pattern Recognition · Computer Science 2018-08-29 Guodong Xu , Chaoqiang Liu , Hui Ji

This paper introduces a two-and multi-level phase mask design for improved depth of focus. A novel technique is proposed incorporating cubic and generalized cubic wavefront coding (WFC). The obtained system is optical-electronic requiring…

Optics · Physics 2017-07-26 Vladimir Katkovnik , Nicholas Hogasten , Karen Egiazarian

In this proposal, we design a learned multi-frequency image compression approach that uses generalized octave convolutions to factorize the latent representations into high-frequency (HF) and low-frequency (LF) components, and the LF…

Image and Video Processing · Electrical Eng. & Systems 2020-09-29 Jianping Lin , Mohammad Akbari , Haisheng Fu , Qian Zhang , Shang Wang , Jie Liang , Dong Liu , Feng Liang , Guohe Zhang , Chengjie Tu

Terahertz subwavelength imaging aims at developing THz microscopes able to resolve deeply subwavelength features. To improve the spatial resolution beyond the diffraction limit, a current trend is to use various subwavelength probes to…

Paradoxically, imaging with resolution much below the wavelength $\lambda$ - now common place in the visible spectrum - remains challenging at lower frequencies, where arguably it is needed most due to the large wavelengths used. Techniques…

Optics · Physics 2023-12-12 Alessandro Tuniz , Boris T. Kuhlmey

We demonstrate structured illumination super-resolution imaging in the Terahertz (THz) frequency band using the Virtually Structured Detection (VSD) method. Leveraging our previously reported high-speed, high-sensitivity atomic-based THz…

Computational imaging modalities support a simplification of the active architectures required in an imaging system and these approaches have been validated across the electromagnetic spectrum. Recent implementations have utilized…

Classical Physics · Physics 2016-08-24 Thomas Fromenteze , Xiaojun Liu , Michael Boyarsky , Jonah Gollub , David R. Smith

We propose in this paper a novel two-stage Projection Correction Modeling (PCM) framework for image reconstruction from (non-uniform) Fourier measurements. PCM consists of a projection stage (P-stage) motivated by the multi-scale Galerkin…

Computer Vision and Pattern Recognition · Computer Science 2017-06-01 Weihong Guo , Guohui Song , Yue Zhang