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Related papers: Frequency chirped Fourier-Transform spectroscopy

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The technologically-relevant task of feature extraction from data performed in deep-learning systems is routinely accomplished as repeated fast Fourier transforms (FFT) electronically in prevalent domain-specific architectures such as in…

The integration of miniaturized optical spectrometers into mobile platforms will have an unprecedented impact on applications ranging from unmanned aerial vehicles (UAVs) to mobile phones. To address this demand, silicon photonics stands…

Applied Physics · Physics 2018-05-09 Mario C. M. M. Souza , Andrew Grieco , Newton C. Frateschi , Yeshaiahu Fainman

Frequency upconversion technique offers an appealing approach for sensitive mid-infrared (MIR) imaging at room temperature. However, the spatial resolution of the upconversion imager has been notoriously restricted by the limited transverse…

We introduce a novel laser-scanning optical microscopy technique that employs optical-frequency-comb (OFC) lasers. This method facilitates multimodal spectroscopic imaging by analyzing interferograms produced via a dual-comb spectroscopic…

In recent years there has been a growing interest in the fractional Fourier transform driven by its large number of applications. The literature in this field follows two main routes. On the one hand, the areas where the ordinary Fourier…

Numerical Analysis · Mathematics 2012-01-26 Rafael G. Campos , J. Rico-Melgoza , Edgar Chávez

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.…

Tunable lasers, with the ability to continuously adjust their emission wavelengths, have found widespread applications across various fields such as biomedical imaging, coherent ranging, optical communications and spectroscopy. In these…

Optics · Physics 2024-03-22 Baoqi Shi , Yi-Han Luo , Wei Sun , Yue Hu , Jinbao Long , Xue Bai , Anting Wang , Junqiu Liu

We have developed a hyperspectral imaging scheme that involves a combination of dual-comb spectroscopy and Hadamard-transform-based single-pixel imaging. The scheme enables us to obtain 12,000 hyperspectral images of amplitude and phase at…

We describe the performance of our latest generations of sensitive wide-band high-resolution digital Fast Fourier Transform Spectrometer (FFTS). Their design, optimized for a wide range of radio astronomical applications, is presented.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Bernd Klein , Stefan Hochgürtel , Ingo Krämer , Andreas Bell , Klaus Meyer , Rolf Güsten

We have demonstrated a new technique that provides massively parallel comb spectroscopy sensitive specifically to ions through the combination of cavity-enhanced direct frequency comb spectroscopy with velocity modulation spectroscopy.…

Atomic Physics · Physics 2015-05-28 Laura C. Sinclair , Kevin C. Cossel , Tyler Coffey , Jun Ye , Eric A. Cornell

Fourier transform spectroscopy (FTS) has been widely used as an analytical tool for many applications in science and engineering. In this paper, we describe the operation principle and practical implementation of an FTS prototype. First,…

Instrumentation and Detectors · Physics 2023-02-02 Sohrab Sheikh-Sofla , Mohammad Neshat

Laser spectroscopy and interferometry have provided an unparalleled view into the fundamental nature of matter and the universe through ultra-precise measurements of atomic transition frequencies and gravitational waves. Optical frequency…

Given a time series vector, how can we efficiently compute a specified part of Fourier coefficients? Fast Fourier transform (FFT) is a widely used algorithm that computes the discrete Fourier transform in many machine learning applications.…

Machine Learning · Computer Science 2020-08-31 Yong-chan Park , Jun-Gi Jang , U Kang

It was recently demonstrated that broadband quantum cascade lasers can operate as frequency combs. As such, they operate under direct electrical pumping at both mid-infrared and THz frequencies, making them very attractive for dual-comb…

The short-time Fourier transform (STFT) usually computes the same number of frequency components as the frame length while overlapping adjacent time frames by more than half. As a result, the number of components of a spectrogram matrix…

Signal Processing · Electrical Eng. & Systems 2020-10-29 Daichi Kitahara

A joint frame and carrier frequency synchronization algorithm for coherent optical systems, based on the digital computation of the fractional Fourier transform (FRFT), is proposed. The algorithm utilizes the characteristics of energy…

Signal Processing · Electrical Eng. & Systems 2018-01-08 Oluyemi Omomukuyo , Shu Zhang , Octavia Dobre , Ramachandran Venkatesan , Telex M. N. Ngatched

Sub-Doppler laser spectroscopy is a crucial technique for laser frequency stabilization, playing a significant role in atomic physics, precision measurement, and quantum communication. However, recent efforts to improve frequency stability…

Rotation is a common motional form in nature, existing from atoms and molecules, industrial turbines to astronomical objects. However, it still lacks an efficient and reliable method for real-time image processing of a fast-rotating object.…

We consider finite approximations of a fractal generated by an iterated function system of affine transformations on $\mathbb{R}^d$ as a discrete set of data points. Considering a signal supported on this finite approximation, we propose a…

Functional Analysis · Mathematics 2016-07-14 Calvin Hotchkiss , Eric S. Weber

Fourier domain mode-locking (FDML) has been a popular laser design for high speed optical frequency domain imaging (OFDI) but achieving long coherence lengths, and therefore imaging range, has been challenging. The narrow instantaneous…

Optics · Physics 2019-01-16 Norman Lippok , Meena Siddiqui , Benjamin J. Vakoc , Brett E. Bouma