Results 211 to 220 of about 87,415 (264)

Phase Coherence Imaging

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2009
A new method for grating and side lobes suppression in ultrasound images is presented. It is based on an analysis of the phase diversity at the aperture data. Two coherence factors, namely the phase coherence factor (PCF) and the sign coherence factor (SCF), are proposed to weight the coherent sum output.
Jorge, Camacho, Montserrat, Parrilla, Carlos, Fritsch   +2 more
openaire   +2 more sources

Snapshot Coherence Tomographic Imaging

IEEE Transactions on Computational Imaging, 2021
We demonstrate a high-throughput computation-efficient snapshot coherence tomographic imaging method by combining interferometric coding and compressive sampling. We first encode the depth distribution of a three-dimensional (3D) object into the spectrum of a light field, using the principle of optical coherence tomography (OCT), i.e.
Mu Qiao, Yangyang Sun, Jiawei Ma, Ziyi Meng 0001, Xuan Liu, Xin Yuan 0002   +5 more
openaire   +2 more sources

Coherent diffractive imaging and partial coherence

Physical Review B, 2007
We formulate coherent diffractive imaging in the framework of partially spatially coherent diffraction. We find that the reconstruction can be critically dependent on the degree of coherence in the illuminating field and that even a small departure from full coherence may invalidate the conventional assumption that a mapping exists between an exit ...
Williams, Garth J., Quiney, Harry M., Peele, Andrew G., Nugent, Keith A.   +3 more
openaire   +1 more source

Noise Suppression in Coherent Imaging

Applied Optics, 1973
Several noise suppression techniques in coherent imaging systems are described. For holographic imaging the diffuse wave, periodic phase modulation, and multiple wave techniques are compared and the implementation of the last is considered. For lens-type imaging systems the use of multiple incoherent waves results in excellent noise suppression.
J, Upatnieks, R W, Lewis
openaire   +2 more sources

Coherency matrix formulation for partially coherent imaging to evaluate the degree of coherence for image

Journal of the Optical Society of America A, 2012
This paper defines a matrix from which coherence property of imaging by partially coherent Koehler illumination is determined. The matrix termed coherency matrix in imaging system is derived by the space average of a product of a column vector and its transpose conjugate where each row of the column vector represents mutually incoherent light.
openaire   +2 more sources

Coherent multistatic ISAR imaging

IET International Conference on Radar Systems (Radar 2012), 2012
This paper presents methods for Coherent Multistatic Radar Imaging for Non Cooperative Target Recognition (NCTR) with a network of radar sensors. Coherent Multistatic Radar Imaging is based on an extension of existing monostatic ISAR algorithms to the multistatic environment.
Dorp, Ph. van, Otten, M.P.G., Verzeilberg, J.M.M.   +2 more
openaire   +2 more sources

Chrono-coherent imaging for medicine

IEEE Transactions on Biomedical Engineering, 1989
We describe a new method for imaging with visible and near visible light inside media, such as tissues, which have strong light scattering. The chrono-coherent imaging (CCI) method is demonstrated in this paper for a transmission geometry where an absorbing object is completely hidden from normal visual observation by light scattering of the media. The
Kenneth G. Spears, Jenifer Serafin, Nils H. Abramson, Xinming Zhu, Hans Bjelkhagen   +4 more
openaire   +5 more sources

Coherent array optical imaging

Applied Optics, 1991
This paper describes a technique that allows a severely distorted coherent optical array receiver to produce images comparable to conventional monolithic imaging systems. The technique is based on using a phase synchronizing point source as a reference to eliminate phase errors in the array.
S E, Clark, L R, Jones, L F, Desandre
openaire   +2 more sources