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Related papers: Wide-field Fourier transform spectral imaging

200 papers

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…

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

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…

Terahertz microscopy has attracted attention owing to distinctive characteristics of the THz frequency region, particularly non-ionizing photon energy, spectral fingerprint, and transparency to most nonpolar materials. Nevertheless, the…

Intensity, wavevector, phase, and polarization are the most important parameters of any light beam. Understanding the wavevector distribution has emerged as a very important problem in recent days, especially at nanoscale. It provides…

Optics · Physics 2020-01-22 Adarsh B. Vasista , Deepak K. Sharma , G V Pavan Kumar

Both of Wavelet and Fast Fourier Transform are strong signal processing tools in the field of Data Analysis. In this paper fast fourier transform (FFT) and Wavelet Transform are employed to observe some important features of Solar image…

Computer Vision and Pattern Recognition · Computer Science 2013-12-11 Sabyasachi Mukhopadhyay , Debadatta Dash , Swapnil Barmase , Prasanta K Panigrahi

Photonic computing has emerged as a promising platform for accelerating computational tasks with high degrees of parallelism, such as image processing and neural network. We present meta-DFT (discrete Fourier transform), a single layer…

We have developed a digital fast Fourier transform (FFT) spectrometer made of an analog-to-digital converter (ADC) and a field-programmable gate array (FPGA). The base instrument has independent ADC and FPGA modules, which allow us to…

Instrumentation and Methods for Astrophysics · Physics 2017-07-26 Kazumasa Iwai , Yûki Kubo , Hiromitsu Ishibashi , Takahiro Naoi , Kenichi Harada , Kenji Ema , Yoshinori Hayashi , Yuichi Chikahiro

The changes in brightness of an astronomical source as a function of time are key probes into that source's physics. Periodic and quasi-periodic signals are indicators of fundamental time (and length) scales in the system, while stochastic…

Instrumentation and Methods for Astrophysics · Physics 2023-08-08 Matteo Bachetti , Daniela Huppenkothen

The Fourier inversion of phased coherent diffraction patterns offers images without the resolution and depth-of-focus limitations of lens-based tomographic systems. We report on our recent experimental images inverted using recent…

We introduce a new modality for dynamic phase imaging in confocal microscopy based on synthetic optical holography. By temporal demultiplexing of the detector signal into a series of holograms, we record time-resolved phase images directly…

Optics · Physics 2019-04-09 Martin Schnell , P. Scott Carney , Rainer Hillenbrand

We introduce a deepfake video detection approach that exploits pixel-wise temporal inconsistencies, which traditional spatial frequency-based detectors often overlook. Traditional detectors represent temporal information merely by stacking…

Computer Vision and Pattern Recognition · Computer Science 2025-07-11 Taehoon Kim , Jongwook Choi , Yonghyun Jeong , Haeun Noh , Jaejun Yoo , Seungryul Baek , Jongwon Choi

Many phenomena are described by bivariate signals or bidimensional vectors in applications ranging from radar to EEG, optics and oceanography. The time-frequency analysis of bivariate signals is usually carried out by analyzing two separate…

Methodology · Statistics 2016-09-09 Julien Flamant , Nicolas Le Bihan , Pierre Chainais

Fast Fourier Transform (FFT) relies on the HRV frequency-domain analysis techniques. It requires re-sampling of the inherently unevenly sampled heartbeat time-series (RR tachogram) to produce an evenly sampled time series of the heartbeat.…

Medical Physics · Physics 2022-08-04 Amin Gasmi

Fluorescence microscopy is widely employed for the analysis of living biological samples; however, the utility of the resulting recordings is frequently constrained by noise, temporal variability, and inconsistent visualisation of signals…

Computer Vision and Pattern Recognition · Computer Science 2026-01-16 Hassan Eshkiki , Sarah Costa , Mostafa Mohammadpour , Farinaz Tanhaei , Christopher H. George , Fabio Caraffini

The extraction of information carried by light plays an increasingly important role in optical communication, imaging, and detection. However, the information can only be successfully extracted when the light pulse is comparably strong,…

Optics · Physics 2026-05-25 Zhen Yang , Zeng-Quan Yan , Li Wang , Xiao-Wei Wang , Ka-Di Zhu , Xian-Min Jin

We introduce a imaging modality that works by transiently masking image-subregions during a single exposure of a CCD frame. By offsetting subregion exposure time, temporal information is embedded within each stored frame, allowing…

Quantitative Methods · Quantitative Biology 2016-09-08 Gil Bub , Matthias Tecza , Michiel Helmes , Peter Lee , Peter Kohl

The nonstationary nature of signals and nonlinear systems require the time-frequency representation. In time-domain signal, frequency information is derived from the phase of the Gabor's analytic signal which is practically obtained by the…

Information Theory · Computer Science 2016-04-19 Pushpendra Singh

Diffraction imaging of non-equilibrium dynamics at atomic resolution is becoming possible with X-ray free-electron lasers. However, there are unresolved problems with applying this method to objects that are confined in only one dimension.…

Strongly Correlated Electrons · Physics 2018-02-19 Kenneth R. Beyerlein

Optical two-dimensional Fourier-transformed (2DFT) spectroscopy is used to study the coherent optical response of potassium vapor in a thin transmission cell. Rephasing and non-rephasing spectra of the D1 and D2 transitions are obtained and…

Atomic Physics · Physics 2011-11-29 X. Dai , A. D. Bristow , D. Karaiskaj , S. T. Cundiff

Full-field optical coherence tomography (FF-OCT) offers label-free, high-resolution imaging of biological samples but remains limited by slow acquisition due to piezoelectric mirror modulation. We present a continuous-scanning FF-OCT method…

Optics · Physics 2025-09-11 Charlie Kersuzan , Anirban Jana , Amaury Badon