Patent
Polarization four-step phase shifting method for digital speckle interferometry
TLDR
In this paper, a polarization four-step phase shifting method for digital speckle interferometry was proposed, which replaces piezoelectric ceramics with two rotatable polarizers.Abstract:
The invention discloses a polarization four-step phase shifting method for digital speckle interferometry. According to the polarization four-step phase shifting method for digital speckle interferometry, polarization beam splitting prisms, a beam expander, quarter wave plates and polarizers are adopted to establish a polarization four-step phase shifting optical path; in a phase shifting process,two polarizers are rotated, so that 0-degree, 90-degree, 180-degree and 270-degree four-step phase shifting can be realized, and corresponding speckle images are acquired; and a random phase field atan initial moment is restored through a four-step phase shifting algorithm. Compared with a traditional time phase shifting method, the method replaces piezoelectric ceramics with two rotatable polarizers, and therefore, the hysteresis, nonlinearity and creep interference of the piezoelectric ceramics can be avoided, stable speckle images can be acquired, and accurate random phase extraction canbe realized.read more
Citations
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Optical fiber point diffraction interference apparatus and method for transient three-coordinate measurement
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References
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Patent
Three-dimensional scan measuring device and method suitable for strong reflection surface
Wei Feng,Zhang Fumin,Qu Xinghua +2 more
TL;DR: In this article, a three-dimensional scan measuring method suitable for a strong reflection surface was proposed. But the method was not suitable for strong reflection surfaces and the measurement of the to-be-measured image was performed through a phase method based on grating projection.
Patent
Whole-field optically coherent chromatographic imaging system with no-dispersion phase shifter
Zhihua Ding,Yaliang Yang,Ling Wu +2 more
TL;DR: In this article, a whole-field optically coherent chromatographic imaging system with a no-dispersion phase shifter is presented, where the light from the light source after passing through a collimating lens, a wide-band beam splitting prism, a polaroid, a nodisparity phase shifters, and a wideband polarizing beam-splitting prism successively is divided into two light beams, and one of the light beams reaches to the reference mirror through the first micro objective on one precise electrically controlled platform, while the other light beam reaches
Patent
Method and system thereof for measuring three-dimensional surface shape of object by electronic speckle phase shift technology
Ping Sun,Ruidong Zhao +1 more
TL;DR: In this paper, an electronic speckle phase shift technology was used to measure the three-dimensional surface shape of an object by generating alternately dark and bright interference fringes on the surface of the object.
Patent
Three-dimensional rapid measurement method for raster projection based on defocusing phase-unwrapping of projector
TL;DR: In this paper, a three-dimensional rapid measurement method for raster projection based on defocusing phase-unwrapping of a projector is presented, and the method comprises the following steps: generating various types of raster patterns through a computer; enabling the raster pattern to be projected on a to-be-measured object in a defocusing manner through the projector; employing a camera to collect raster images; employing four-step phase shift method to obtain a main value phase; employing an additional two-value raster image pattern, and employing a gray-scale