English
Related papers

Related papers: Fixed-detector tilt--defocus sensing by upstream s…

200 papers

Accessing the low-energy non-equilibrium dynamics of materials and their polaritons with simultaneous high spatial and temporal resolution has been a bold frontier of electron microscopy in recent years. One of the main challenges lies in…

This paper is concerned with a direct sampling method for imaging the support of a frequency-dependent source term embedded in a homogeneous and isotropic medium. The source term is given by the Fourier transform of a time-dependent source…

Numerical Analysis · Mathematics 2022-12-12 Hongxia Guo , Guanghui Hu , Mengjie Zhao

This paper presents a general scheme for enhancing the convergence and performance of DETR (DEtection TRansformer). We investigate the slow convergence problem in transformers from a new perspective, suggesting that it arises from the…

Computer Vision and Pattern Recognition · Computer Science 2024-07-17 Xiuquan Hou , Meiqin Liu , Senlin Zhang , Ping Wei , Badong Chen , Xuguang Lan

This paper investigates beamforming-gain maximization for a fluid reconfigurable intelligent surface (FRIS)-assisted downlink system, where each active port applies a finite-resolution unit-modulus phase selected from a discrete codebook.…

Signal Processing · Electrical Eng. & Systems 2026-02-13 Hong-Bae Jeon

A novel test of time-reversal invariance in proton-deuteron scattering is planned as an internal target transmission experiment at the cooler synchrotron COSY. The P-even, T-odd observable is the polarization correlation $A_{y,xz}$ of the…

A shearing interferometer is presented which uses polarization control to shear the wavefront and to modulate the interference pattern. The shear is generated by spatial walk-off in a birefringent crystal. By adjusting the orientation of…

Optics · Physics 2012-12-11 Peter Beyersdorf , Mark Cordier

In this paper, we present a light-weight detection transformer, LW-DETR, which outperforms YOLOs for real-time object detection. The architecture is a simple stack of a ViT encoder, a projector, and a shallow DETR decoder. Our approach…

Computer Vision and Pattern Recognition · Computer Science 2024-06-06 Qiang Chen , Xiangbo Su , Xinyu Zhang , Jian Wang , Jiahui Chen , Yunpeng Shen , Chuchu Han , Ziliang Chen , Weixiang Xu , Fanrong Li , Shan Zhang , Kun Yao , Errui Ding , Gang Zhang , Jingdong Wang

Time-resolved scanning near-field optical microscopy (tr-SNOM) enables the measurement of the dynamic optical response of functional surfaces beyond the diffraction limit. Experimental challenges are imposed both by the use of a pulsed…

Optics · Physics 2026-04-16 Philipp Schwendke , Julia Stähler , Samuel Palato

The nonlinear curvature wavefront sensor (nlCWFS) uses multiple (typically four) out-of-focus images to reconstruct the phase and amplitude of a propagating light beam. Because these images are located between the pupil and focal planes,…

Instrumentation and Methods for Astrophysics · Physics 2024-07-23 Caleb A. Abbott , Justin R. Crepp , Stanimir O. Letchev , Connor M. Smith

Recently, Transformer-based methods, which predict polygon points or Bezier curve control points for localizing texts, are popular in scene text detection. However, these methods built upon detection transformer framework might achieve…

Computer Vision and Pattern Recognition · Computer Science 2022-11-29 Maoyuan Ye , Jing Zhang , Shanshan Zhao , Juhua Liu , Bo Du , Dacheng Tao

Frequency dependent squeezing is the main upgrade for achieving broadband quantum noise reduction in upcoming observation runs of gravitational wave detectors. The proper frequency dependence of the squeezed quadrature is obtained by…

In this paper it is established that any jointly controllable, jointly observable, multi-channel, discrete or continuous time linear system with a strongly connected neighbor (communication) graph can be exponentially stabilized with any…

Systems and Control · Electrical Eng. & Systems 2022-12-02 Fengjiao Liu , Lili Wang , Daniel Fullmer , A. Stephen Morse

AIMS: We have found that the interferometric visibilities of VLTI-AMBER observations, extracted via the standard reduction package, are significantly biased when faint targets are concerned. The visibility biases derive from a time variable…

Astrophysics · Physics 2009-11-13 G. Li Causi , S. Antoniucci , E. Tatulli

Many aquatic organisms are able to track ambient flow disturbances and locate their source. These tasks are particularly challenging because they require the organism to sense local flow information and respond accordingly. Details of how…

Optimization and Control · Mathematics 2018-04-10 Brendan Colvert , Eva Kanso

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

We explain and demonstrate a new method of force- and position-calibration for optical tweezers with back-focal-plane photo detection. The method combines power spectral measurements of thermal motion and the response to a sinusoidal motion…

We investigate interferometric techniques to estimate the deflection angle of an optical beam and compare them to the direct detection of the beam deflection. We show that quantum metrology methods lead to a unifying treatment for both…

Quantum Physics · Physics 2020-08-12 S. P. Walborn , G. H. Aguilar , P. L. Saldanha , L. Davidovich , R. L. de Matos Filho

We present the first on-sky results of the micro-lens ring tip-tilt (MLR-TT) sensor. This sensor utilizes a 3D printed micro-lens ring feeding six multi-mode fibers to sense misaligned light, allowing centroid reconstruction. A tip-tilt…

Optical time-reversal techniques are being actively developed to focus light through or inside opaque scattering media. When applied to biological tissue, these techniques promise to revolutionize biophotonics by enabling deep-tissue…

Biological Physics · Physics 2016-11-07 Yuecheng Shen , Yan Liu , Cheng Ma , Lihong V. Wang

Context. Narrow-band interference filters can be tuned toward shorter wavelengths by tilting them from the perpendicular to the optical axis. This can be used as a cheap alternative to real tunable filters, such as Fabry-P\'erot…

Instrumentation and Methods for Astrophysics · Physics 2011-08-31 Mats G. Löfdahl , Vasco M. J. Henriques , Dan Kiselman
‹ Prev 1 3 4 5 6 7 10 Next ›