Results 251 to 260 of about 198,881 (290)

Phase-shift calibration algorithm for phase-shifting interferometry

Journal of the Optical Society of America A, 2000
We propose a novel phase-shift calibration algorithm. With this technique we determine the unknown phase shift between two interferograms by examining the sums and differences of the intensities on each interferogram at the same spatial location, i.e., I1(x, y) +/- I2(x, y). These intensities are normalized so that they become sinusoidal in form.
X, Chen, M, Gramaglia, J A, Yeazell
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Blind phase shift estimation in phase-shifting interferometry

Journal of the Optical Society of America A, 2007
A blind phase shift estimation algorithm that allows simultaneous calculation of phases and phase shifts from three or more interferograms is presented. In phase-shifting interferometry, the phase shift errors introduce specific correlations between the calculated background intensity distribution and the fringe component.
Hongwei, Guo, Yingjie, Yu, Mingyi, Chen
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Phase-shift extraction for generalized phase-shifting interferometry

Optics Letters, 2009
A simple algorithm for blind extraction of phase shifts is proposed for generalized phase-shifting interferometry from only three interferograms. Based on the statistical property of the object wave, the algorithm calculates approximately the involved phase shifts as initial values. The extraction is further improved by an iterative method, considering
Gao, Peng, Yao, Baoli, Lindlein, Norbert, Mantel, Klaus, Harder, Irina, Geist, Eduard   +5 more
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Phase-shifted Fresnel axicon

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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Stroboscopic phase-shifting interferometry

Optics Letters, 1987
The 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-amplified interferometry

Optics Letters, 2018
We 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, Egor Liokumovitch, Daniel Gotliv, Shmuel Sternklar   +3 more
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Reference phase shift determination in phase shifting interferometry

Optics and Lasers in Engineering, 1995
Abstract The phase shifting technique has recently seen application to many types of interferometers, including holographic, speckle and moire systems for strain analysis. In these applications, close control of the phase shifts may be impossible due to the effect of mechanical vibrations, and this presents difficulties when extracting the phase ...
K.E. Perry, J. McKelvie
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Phase-shifting Gabor holography

Optics Letters, 2009
We present a modified Gabor-like setup able to recover the complex amplitude distribution of the object wavefront from a set of inline recorded holograms. The proposed configuration is characterized by the insertion of a condenser lens and a spatial light modulator (SLM) into the classical Gabor configuration.
Vicente, Micó, Javier, García, Zeev, Zalevsky, Bahram, Javidi   +3 more
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Phase-shifting speckle interferometry

Applied Optics, 1985
Speckle 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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Filtering without Phase Shift

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, J P, Giolma, C, Wall, R F, Quick   +3 more
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