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Accurate Phase Shift Extraction for Generalized Phase-Shifting Interferometry
Chinese Physics Letters, 2010An accurate phase shift extraction method for generalized phase-shifting interferometry is suggested. Based on the nearly random phase distribution of the diffraction field of the object, a singular formula is derived to calculate the unknown phase shift without the requirements of an iteration process or the selection of the correct value from two or ...
Xu Xian-Feng +3 more
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IEEE Transactions on Biomedical Engineering, 1975
The influences of phase shifts are extremely important in the determination of filtered waveforms and therefore in the interpretation of many biosignals. Low frequency shifts from high pass filtering, for example, are significant because large time displacements result from small phase deviations in the vicinity of the corner frequency.
R L, Longini +3 more
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The influences of phase shifts are extremely important in the determination of filtered waveforms and therefore in the interpretation of many biosignals. Low frequency shifts from high pass filtering, for example, are significant because large time displacements result from small phase deviations in the vicinity of the corner frequency.
R L, Longini +3 more
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Measurement of the photorefractive phase shift
Optics Letters, 1992We present a method to separate the effects of trap gratings and electro-optic gratings in BaTiO(3) crystals, and we determine the true spatial shift between the electro-optic grating and the optical intensity pattern. At small beam-crossing angles this spatial shift is strongly affected by a photogalvanic current in the crystal.
R S, Cudney +3 more
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Phase-shift-amplified interferometry
Optics Letters, 2018We present a new technique for improving the sensitivity of an interferometer, phase-shift-amplified interferometry (PAI), which is based on two embedded interferometers. The internal interferometer, which is biased in anti-phase, amplifies the phase shift; the external interferometer converts this into an amplified intensity shift. PAI can improve the
Moshe Ben Ayun +3 more
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Phase Shifts and Linear Dependencies
2006 IEEE International Symposium on Circuits and Systems, 2006Two-dimensional scan design is a widely used BIST architecture for pseudo-random and pseudo-exhaustive testing. However, linear dependencies that arise due to the properties of the test-pattern generators in use have a negative impact on fault coverage. To alleviate this problem, networks of XOR gates known as phase shifters are often used.
Jayawant Kakade, Dimitrios Kagaris
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Stroboscopic phase-shifting interferometry
Optics Letters, 1987The implementation of a new type of phase-shifting, self-referencing interferometer that simultaneously achieves the phase shift and separation of heams with a stationary diffraction grating is described. The capabilities of stroboscopic interferometry are demonstrated with results from an experiment in which the rapidly varying surface deformations of
O Y, Kwon, D M, Shough, R A, Williams
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Phase-shift coherence holography
Optics Letters, 2010We propose and experimentally demonstrate a new reconstruction scheme for coherence holography using computer-generated phase-shift coherence holograms. A 3D object encoded into the spatial coherence function is reconstructed directly from a set of incoherently illuminated computer-generated holograms with numerically introduced phase shifts.
Dinesh N, Naik +3 more
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Phase-shifting digital holography
Optics Letters, 1997A new method for three-dimensional image formation is proposed in which the distribution of complex amplitude at a plane is measured by phase-shifting interferometry and then Fresnel transformed by a digital computer. The method can reconstruct an arbitrary cross section of a three-dimensional object with higher image quality and a wider viewing angle ...
I, Yamaguchi, T, Zhang
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Continuous phase-shifting holography
Journal of the Optical Society of America A, 2019A scanning full-field interferometer is a key device in the optical scheme of digital hyperspectral hologram registration. Behind the theory of hyperspectral holography is Fourier transform spectroscopy, wherein the set of spectrally resolved complex amplitudes of the object’s hyperspectral field is obtained via the Fourier transform of a series of ...
Sergey G. Kalenkov +2 more
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An accurate phase shift extraction algorithm for phase shifting interferometry
Optics Communications, 2018Abstract The accuracy of phase shift extraction has a significant influence on measurement results in surface micro-topography interferometry. Phase shifting errors are mainly caused by nonlinearity of the employed phase shifter, environmental turbulence, camera imperfection and so on. In this paper, a general algorithm based on Lissajous figures and
Zhongsheng Zhai +5 more
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