Results 251 to 260 of about 1,068,113 (278)
Some of the next articles are maybe not open access.
Mitigation of Speckle Noise in Optical Coherence Tomograms
2018Optical Coherence Tomography (OCT) is a promising high-resolution imaging technique that works based on low coherent interferometry. However, like other low coherent imaging modalities, OCT suffers from an artifact called, speckle. Speckle reduces the detectability of diagnostically relevant features in the tissue.
Adabi S. +5 more
openaire +1 more source
Escaping path approach for speckle noise reduction
SPIE Proceedings, 2015A novel fast filtering technique for multiplicative noise removal in ultrasound images was presented in this paper. The proposed algorithm utilizes concept of digital paths created on the image grid presented in [1] adapted to the needs of multiplicative noise reduction.
Marek Szczepanski, Krystian Radlak
openaire +1 more source
Speckle Noise Reduction by Random Phase Shifters
Japanese Journal of Applied Physics, 1974Experimental results are given that show that a random phase shifter (RPS) is effective in reducing speckle noise caused by optical defects in coherent imaging systems, including holographic imaging systems. Here the RPS is composed of many tiny transparent blocks, each of which gives a definite phase shift such as O or pi to the transmitting light ...
openaire +2 more sources
Effect of scintillation noise in heterodyne speckle photogrammetry
Applied Optics, 1984Heterodyne interferometry provides an accurate method of measuring specklegram halo fringes for strain analysis; however, when fringe contrast is less than unity, the uncorrelated portions of the fields generate a background scintillation that is a random function of specklegram and detector positions. In practice, this scintillation effect establishes
openaire +2 more sources
Laser Speckle Pattern-A Narrowband Noise Model
Bell System Technical Journal, 1970We represent by an electrical model the imaging of a one-dimensional coherently illuminated and diffusely reflecting surface by an optical system with a rectangular aperture. We then obtain the statistical properties of the image intensity from the statistical properties of the square of the envelope of a narrowband noise signal in the electrical model.
openaire +1 more source
Speckle-noise filtering based on non-local mean sparse principal component analysis method
Optics and Lasers in Engineering, 2023Osamu Matoba +2 more
exaly
When is speckle noise multiplicative?
Applied Optics, 1982M, Tur, K C, Chin, J W, Goodman
openaire +2 more sources