scispace - formally typeset
Search or ask a question
Topic

Speckle imaging

About: Speckle imaging is a research topic. Over the lifetime, 3730 publications have been published within this topic receiving 62354 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: The possibility of obtaining comparable, setup-independent results in blood perfusion monitoring can contribute to better applicability of LASCA.
Abstract: In laser speckle contrast analysis (LASCA) used for imaging of blood flow, besides the moving blood cells, the speckle pattern is also influenced by the imaging system and scattering properties of the laser-illuminated static surface. A latex microsphere (650 nm size) emulsion was covered with scattering semitransparent materials (Teflon foils, tracing paper). Speckle images were recorded with different exposure times (0.2 ms-500 ms), and correlation times were determined by parameterizing the theoretical contrast-exposure time function. The correlation times obtained for covered and uncovered microsphere emulsions were in good agreement. The possibility of obtaining comparable, setup-independent results in blood perfusion monitoring can contribute to better applicability of LASCA.

25 citations

Journal ArticleDOI
TL;DR: A digital phase-mapping method has been developed for application in real-time electronic speckle interferometry studies and its principles and application to a continuously deforming object are described.
Abstract: A digital phase-mapping method has been developed for application in real-time electronic speckle interferometry studies Its principles and application to a continuously deforming object are described An efficient digital image-processing algorithm has been developed that permits quantitative interpretation of the resulting phase maps

25 citations

Journal ArticleDOI
TL;DR: In this paper, the authors studied the formation cause of speckle noise in the reconstructed image of digital holography and acquired the conclusion that the small size of hologram aperture diffraction aggravates the noise of reconstructed image and has been one of the primary noise sources in the reconstruction process.

25 citations

Journal ArticleDOI
TL;DR: In this article, the authors improved the stability and temporal response of the laser speckle strain gauge that detects strain caused by surface deformation by using a pair of linear image sensors.
Abstract: We have improved the stability and temporal response of the laser speckle strain gauge that detects strain from speckle displacement caused by surface deformation. In the gauge, a narrow laser beam is incident on a diffuse surface, and speckle patterns appearing in the light scattered through the symmetrical angles are detected by a pair of linear image sensors. Speckle displacement is derived by a real-time correlator as the peak of the cross correlation between the current frame and a reference frame of the sensor driven at 1000 frames per second. The reference frame is fixed until the correlation peak becomes lower than a threshold. Using a pair of image sensors, followed by the correlators, and a laser of output power of a few tens of milliwatts, we could measure dynamic strain of polymer films at the frequency between a fraction of hertz and 100 Hz. The resolution of the gauge, which only depends on geometry of the optical system and the sensor pitch, is a few tens of microstrains. The upper limit of the measurement can be extended arbitrarily because small incremental strain is integrated.

25 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present speckle interferometer measurements of 467 binary stars taken at the US Naval Observatory in Washington, DC, using the 66 cm refractor, from 1990 October through 1992 December.
Abstract: We present speckle interferometer measurements of 467 binary stars taken at the US Naval Observatory in Washington, DC, using the 66 cm refractor, from 1990 October through 1992 December. The observing program is designed to provide high-quality observations of binaries in the 03-35 range of separations and as faint as 10.0 mag. More than 8000 measurements have been made to date, of which we report the results for 2329. Not only is it our intent to provide accurate data for interesting binary stars, but also, by careful calibration, to firmly relate the "classical" astrometry of binary stars to that being obtained today by speckle and that which will soon be obtained by other modern techniques such as long-baseline optical interferometry.

25 citations


Network Information
Related Topics (5)
Interferometry
58K papers, 824.8K citations
88% related
Optical fiber
167K papers, 1.8M citations
82% related
Polarization (waves)
65.3K papers, 984.7K citations
81% related
Light scattering
37.7K papers, 861.5K citations
80% related
Emission spectrum
36.9K papers, 878.7K citations
79% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202332
202249
202162
202079
201972
201895