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Simultaneously sensing and resolving the position of measurands along an optical fiber enables numerous opportunities, especially for application in environments where massive sensor deployment is not feasible. Despite significant progress…

Optics · Physics 2023-01-25 Luis Costa , Zhongwen Zhan , Alireza Marandi

The James Webb Space Telescope (JWST) is optimized for observations in the near and mid infrared and will provide essential observations for targets that cannot be conducted from the ground or other missions during its lifetime. The state…

Earth and Planetary Astrophysics · Physics 2016-01-11 Stefanie N. Milam , John A. Stansberry , George Sonneborn , Cristina Thomas

The key features of the MATPHOT algorithm for precise and accurate stellar photometry and astrometry using discrete Point Spread Functions are described. A discrete Point Spread Function (PSF) is a sampled version of a continuous PSF which…

Astrophysics · Physics 2009-11-11 Kenneth J. Mighell

It is critical for James Webb Space Telescope (JWST) science that instrumental units are converted to physical units. We detail the design of the JWST absolute flux calibration program that has the core goal of ensuring a robust flux…

Diffusing wave spectroscopy (DWS) can be employed as an optical rheology tool with numerous applications for studying the structure, dynamics and linear viscoelastic properties of complex fluids, foams, glasses and gels. To carry out DWS…

Soft Condensed Matter · Physics 2018-11-06 Chi Zhang , Mathias Reufer , Danila Gaudino , Frank Scheffold

The principal limitation in many areas of astronomy, especially for directly imaging exoplanets, arises from instability in the point spread function (PSF) delivered by the telescope and instrument. To understand the transfer function, it…

Instrumentation and Methods for Astrophysics · Physics 2021-09-01 Alison Wong , Benjamin Pope , Louis Desdoigts , Peter Tuthill , Barnaby Norris , Chris Betters

The ability to form images through hair-thin optical fibres promises to open up new applications from biomedical imaging to industrial inspection. Unfortunately, deployment has been limited because small changes in mechanical deformation…

In distributed fiber-optic sensing based on optical frequency domain reflectometry (OFDR), Doppler frequency shifts due to the changes of disturbances during one sweep period introduce demodulation errors that accumulate along both the…

Optics · Physics 2024-10-28 Qiang Yang , Weilin Xie , Congfan Wang , Bowen Li , Xin Li , Xiang Zheng , Wei Wei , Yi Dong

A new concept, called the spatio-temporal transfer function (STTF), is introduced to characterise a class of linear time-invariant (LTI) spatio-temporal dynamical systems. The spatio-temporal transfer function is a natural extension of the…

Systems and Control · Electrical Eng. & Systems 2021-11-04 Hua-Liang Wei , Stephen A. Billings

Optical diffraction tomography is an indispensable tool for studying objects in three-dimensions due to its ability to accurately reconstruct scattering objects. Until now this technique has been limited to coherent light because spatial…

The OTFS (Orthogonal Time Frequency Space) is widely acknowledged for its ability to combat Doppler spread in time-varying channels. In this paper, another advantage of OTFS over OFDM (Orthogonal Frequency Division Multiplexing) will be…

Signal Processing · Electrical Eng. & Systems 2024-08-20 Zijun Gong , Fan Jiang , Yuhui Song , Cheng Li , Xiaofeng Tao

PHASECam is the fringe tracker for the Large Binocular Telescope Interferometer (LBTI). It is a near-infrared camera which is used to measure both tip/tilt and fringe phase variations between the two adaptive optics (AO) corrected apertures…

Instrumentation and Methods for Astrophysics · Physics 2020-07-30 Erin R. Maier , Phil Hinz , Denis Defrère , Paul Grenz , Elwood Downey , Steve Ertel , Katie Morzinski , Ewan S. Douglas

When using an electron microscope for imaging of particles embedded in vitreous ice, the objective lens will inevitably corrupt the projection images. This corruption manifests as a band-pass filter on the micrograph. In addition, it causes…

Image and Video Processing · Electrical Eng. & Systems 2020-01-29 Ayelet Heimowitz , Joakim Andén , Amit Singer

In this work we present the numerical evaluation of a new design of fractal intraocular lens studied through a ray-tracing program. To determine the monochromatic and polychromatic performance of these lenses in different theoretical model…

Medical Physics · Physics 2020-06-25 Diego Montagud-Martinez , Vicente Ferrando , Juan A. Monsoriu , Walter D. Furlan

The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a tabletop experiment designed to reproduce the main aspects of wavefront sensing and control (WFSC) for JWST. To replicate the key optical physics of JWST's…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Élodie Choquet , Olivier Levecq , Mamadou N'Diaye , Marshall D. Perrin , Rémi Soummer

The fields of view of Extremely Large Telescopes will contain vast numbers of spatial sampling elements (spaxels) as their Adaptive Optics systems approach the diffraction limit over wide fields. Since this will exceed the detection…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 G. J. Murray , J. R. Allington-Smith

Diffusing-Wave Spectroscopy (DWS) treats the transport of photons through turbid samples as a diffusion process, thereby making it possible to extract the dynamics of scatterers from measured correlation functions. The analysis of DWS data…

Soft Condensed Matter · Physics 2017-12-27 Zahra Fahimi , Frank Aangenendt , Panayiotis Voudouris , Johan Mattson , Hans M. Wyss

The next generation of large telescopes for direct imaging of exoplanets will require segmented primary mirrors. Over both long and short timescales, these telescopes experience segment misalignments which degrade the final science image.…

The VLTI instrument GRAVITY will provide very powerful astrometry by combining the light from four telescopes for two objects simultaneously. It will measure the angular separation between the two astronomical objects to a precision of 10…

Multi-modal image fusion aims to integrate complementary information from multiple source images to produce high-quality fused images with enriched content. Although existing approaches based on state space model have achieved satisfied…

Computer Vision and Pattern Recognition · Computer Science 2026-01-12 Yiming Sun , Zifan Ye , Qinghua Hu , Pengfei Zhu