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We have designed and constructed a ``dispersed Fourier Transform Spectrometer'' (dFTS), consisting of a conventional FTS followed by a grating spectrometer. By combining these two devices, we negate a substantial fraction of the sensitivity…

We present an approach for improving spatial frequency sampling in active incoherent millimeter-wave (AIM) imaging systems using frequency diversity. AIM imaging relies on active transmission of spatio-temporally incoherent signals to…

信号处理 · 电气工程与系统科学 2025-03-12 Jorge R. Colon-Berrios , Jeffrey A. Nanzer

We measured images and Fourier images of fluorescence for 0.11- and 0.22-$\mu$m-diameter dye-doped polystyrene micro-sphere beads on a solid immersion lens, and experimentally verified strongly-angle-dependent fluorescence intensities due…

仪器与探测器 · 物理学 2009-11-07 Masahiro Yoshita , Kazuko Koyama , Motoyoshi Baba , Hidefumi Akiyama

Dispersive Fourier transformation is a powerful technique in which spectral information is mapped into the time domain using chromatic dispersion. It replaces a spectrometer with an electronic digitizer, and enables real-time spectroscopy.…

光学 · 物理学 2009-11-13 J. Chou , D. R. Solli , B. Jalali

We demonstrate an optical frequency analysis method using the Fourier transform of detection times of fluorescence photons emitted from a single trapped 40Ca+ ion. The response of the detected photon rate to the relative laser frequency…

Fluorescence detection, either involving propagating or near-field emission, is widely being used in spectroscopy, sensing and microscopy. Total internal reflection fluorescence (TIRF) confines fluorescence excitation by an evanescent…

定量方法 · 定量生物学 2020-06-24 Martin Oheim , Adi Salomon , Maia Brunstein

Single Pixel (SP) imaging is now a reality in many applications, e.g., biomedical ultrathin endoscope and fluorescent spectroscopy. In this context, many schemes exist to improve the light throughput of these device, e.g., using structured…

计算机视觉与模式识别 · 计算机科学 2019-02-19 Amirafshar Moshtaghpour , José M. Bioucas-Dias , Laurent Jacques

It is shown here that precision is gained by analyzing the interferometric spectra directly from the interferograms, with no previous Fourier transformation to put them in the standard frequency domain. The method is based on the…

仪器与探测器 · 物理学 2018-04-20 Miguel Lagos , Rodrigo Paredes , Cesar Retamal

Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…

光学 · 物理学 2025-12-16 S. A. Wadood , Shaurya Aarav , Kevin Liang , Jason W Fleischer

Infrared (IR) spectroscopy is an indispensable tool for many practical applications including material analysis and sensing. Existing IR spectroscopy techniques face challenges related to the inferior performance and the high cost of…

光学 · 物理学 2017-03-13 Anna Paterova , Shaun Lung , Dmitry Kalashnikov , Leonid Krivitsky

The state-of-the-art automotive radars employ multidimensional discrete Fourier transforms (DFT) in order to estimate various target parameters. The DFT is implemented using the fast Fourier transform (FFT), at sample and computational…

信号处理 · 电气工程与系统科学 2018-01-16 Shaogang Wang , Vishal M. Patel , Athina Petropulu

Accurately estimating the point spread function (PSF) of an optical system requires solving free-space wave propagation, which entails evaluating a diffraction integral. This integral is traditionally computed numerically using Fast Fourier…

图像与视频处理 · 电气工程与系统科学 2026-05-22 Nicholas Ganino , Qi Guo

The spectral resolution of broadband Fourier-transform coherent anti-Stokes Raman spectroscopy is limited by the maximum optical path length difference that can be scanned within a short time in an interferometer. However, alternatives to…

Space-based direct imaging provides prospects for detection and spectral characterization of exoplanets at optical and near-infrared wavelengths. Integral field spectrographs (IFS) have been historically baselined for these mission…

地球与行星天体物理 · 物理学 2024-03-26 Jingwen Zhang , Michael Bottom , Eugene Serabyn

We characterize a new mid-infrared frequency comb generator based on difference frequency generation around 3.2 microns. High power per comb mode (>10-7 W/mode) is obtained over a broad spectral span (>700 nm). The source is used for direct…

Fourier Transform Interferometry (FTI) is an appealing Hyperspectral (HS) imaging modality for many applications demanding high spectral resolution, e.g., in fluorescence microscopy. However, the effective resolution of FTI is limited by…

信息论 · 计算机科学 2019-01-31 A. Moshtaghpour , L. Jacques , V. Cambareri , P. Antoine , M. Roblin

We propose a method to directly visualize the photonic band-structure of micron size photonic crystals using wide angle spectroscopy. By extending Fourier Imaging Spectroscopy sensitivity into the infrared range we have obtained accurate…

We present our investigation into the impact of wavefront errors on high accuracy astrometry using Fourier Optics. MICADO, the upcoming near-IR imaging instrument for the Extremely Large Telescope, will offer capabilities for relative…

天体物理仪器与方法 · 物理学 2020-12-15 J. A. van den Born , W. Jellema , R. Navarro , E. Tolstoy , B. Jayawardhana , A. W. Janssen

We demonstrate a new scheme of infrared spectroscopy with visible light sources and detectors. The technique relies on the nonlinear interference of correlated photons, produced via spontaneous parametric down conversion in a nonlinear…

We demonstrate a novel imaging approach and associated reconstruction algorithm for far-field coherent diffractive imaging, based on the measurement of a pair of laterally sheared diffraction patterns. The differential phase profile…

光学 · 物理学 2018-05-23 G. S. M. Jansen , A. C. C. de Beurs , X. Liu , K. S. E. Eikema , S. Witte