We propose a system that reduces laser display speckles by vibrating the light pipe. A small displacement of the light pipe appears to allow the total reflection of the laser, thereby resulting in a homogenized speckle field that changes with time. In this case, the speckle interference generated by the pattern projected by the laser through the light pipe destroys the spatial homogenization of...

1Reader, Punjabi University,Patiala-147002(Punjab), India, [email protected] 2Reader Punjabi University, Patiala-147002(Punjab), India E-mail:[email protected] Abstract-Today ultrasound and magnetic resonance imaging are essential tools for noninvasive medical diagnosis. One of the fundamental problems in this field is speckle noise, which is a major limitation on image qua...

ABSTRACT Speckle noise is often correlated due to image post-processing or imperfect imaging transfer function. in order to filter correlated speckle noise in a multiscale framework (stationary wavelet decomposition), we propose two approaches, respectively parametric and non parameteric. The first approach is based on a parametric modelisation of the speckle autocorrelation function using a co...

The understanding of cytoskeleton dynamics has benefited from the capacity to generate fluorescent fiducial marks on cytoskeleton components. Here we show that light-induced imprinting of three-dimensional (3D) fluorescent speckles significantly improves speckle signal and contrast relative to classic (random) fluorescent speckle microscopy. We predict theoretically that speckle imprinting usin...

Digital speckle image correlation techniques have been successfully proven to be an accurate displacement analysis tool for a wide range of applications. In this paper, a new Electronic Laser Speckle Pattern Interferometer based on Michelson interferometer is designed. An object beam back scattered of an object surface and a reference beam, originating from the same laser light source are super...

Quantitative analysis of optical coherence tomography data can be strongly hampered by speckle. Here, we introduce a new method to reduce speckle, which leverages from Fourier-domain configurations and operates on individual axial scans. By subdividing the digitized spectrum into a number of distinct narrower windows, each with a different center frequency, several independent speckle patterns ...

We present a method for the detection and localization of inhomogeneities embedded within highly scattering media that employs speckle statistics with a partially coherent light source. Variations in speckle contrast as a function of position are used to interrogate inhomogeneities deeply embedded within scattering media. A numerical model based on photon diffusion theory is introduced to predi...

We report on a new digital signal processing technique that reduces speckle in reconstructions of digital holograms. This is achieved by convolving the three dimensional intensity pattern (the intensity of the propagated DH at a series of different distances) with a 3D point spread function in all three dimensions (x,y,z ). It is based on the fact that the addition of different independent spec...

Laser Speckle Contrast Imaging (LSCI) is an optical technique used to generate blood flow maps with high spatial and temporal resolution. It is well known that in LSCI, the speckle size must exceed the Nyquist criterion to maximize the speckle's pattern contrast. In this work, we study experimentally the effect of speckle-pixel size ratio not only in dynamic speckle contrast, but also on the ca...

A wavelet-based method for speckle suppression in ultrasound images of the thyroid gland is introduced. The classification of image pixels as speckle or part of important image structures is accomplished within the framework of back-propagation tracking and singularity detection of wavelet transform modulus maxima, derived from inter-scale analysis. A comparative study with other de-speckling t...