Results 221 to 230 of about 762,865 (262)
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Algorithm immune to tilt phase-shifting error for phase-shifting interferometers
Applied Optics, 2000As a phase shifter usually suffers from both translational and tilt-shift errors during shifting, so every pixel in the same interferogram will have a different phase-shift value. Thus nonlinear phase-measurement errors cannot be avoided, but even translational-shift error has been corrected effectively.
M, Chen, H, Guo, C, Wei
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Phase-shifting speckle interferometry
Applied Optics, 1985Speckle patterns have high frequency phase data, which make it difficult to find the absolute phase of a single speckle pattern; however, the phase of the difference between two correlated speckle patterns can be determined. This is done by applying phase-shifting techniques to speckle interferometry, which will quantitatively determine the phase of ...
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Optics Letters, 2012
We propose an optical element: a phase-shifted Fresnel axicon for generation of multiple Bessel beams. By giving a binary phase modulation to the standard Fresnel axicon, the proposed element is generated. The phase profile of the binary phase modulation is engineered to generate two and three Bessel beams of equal intensities.
Vijayakumar, A., Bhattacharya, Shanti
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We propose an optical element: a phase-shifted Fresnel axicon for generation of multiple Bessel beams. By giving a binary phase modulation to the standard Fresnel axicon, the proposed element is generated. The phase profile of the binary phase modulation is engineered to generate two and three Bessel beams of equal intensities.
Vijayakumar, A., Bhattacharya, Shanti
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Optics Communications, 1991
Abstract This paper shows the possibility of finding the phase distribution of the wavefront and the mean phase difference between two interfering beams from the series of interferograms used in conventional phase shifting technique, without any additional measurement.
Katsuyuki Okada +2 more
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Abstract This paper shows the possibility of finding the phase distribution of the wavefront and the mean phase difference between two interfering beams from the series of interferograms used in conventional phase shifting technique, without any additional measurement.
Katsuyuki Okada +2 more
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Phase shift in dielectric reflection
Applied Optics, 1987The phase shifts in external dielectric reflection were analyzed as a function of the incident angle. The contrast of the interference fringes formed between the incident and the reflected beams was considered. For the parallel mode the phase shift disappears between 45 degrees and the Brewster angle.
M C, Simon, J M, Simon, M T, Garea
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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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