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Phase-shift calibration algorithm for phase-shifting interferometry
Journal of the Optical Society of America A, 2000We 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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Phase-shift extraction for generalized phase-shifting interferometry
Optics Letters, 2009A 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 +5 more
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Blind phase shift estimation in phase-shifting interferometry
Journal of the Optical Society of America A, 2007A 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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Embedded phase shifting: Robust phase shifting with embedded signals
2015 IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2015We introduce Embedded PS, a new robust and accurate phase shifting algorithm for 3D scanning. The method projects only high frequency sinusoidal patterns in order to reduce errors due to global illumination effects, such as subsurface scattering and interreflections.
Daniel Moreno, Kilho Son, Gabriel Taubin
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Phase retrieval with a three-frame phase-shifting algorithm with an unknown phase shift
Applied Optics, 2005A three-frame phase-shifting algorithm with a constant but unknown phase shift is proposed. The algorithm is based on background-intensity removal prior to phase retrieval to eliminate an undetermined factor in a fringe pattern. The proposed method is validated on three-dimensional profilometry by fringe projection and on deformation measurement by ...
Tay, C.J., Quan, C., Chen, L.
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Reference phase shift determination in phase shifting interferometry
Optics and Lasers in Engineering, 1995Abstract 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 for nonsinusoidal waveforms with phase-shift errors
Journal of the Optical Society of America A, 1995In phase measurement systems that use phase shifting techniques, phase errors that are due to nonsinusoidal waveforms can be minimized by applying synchronous phase shifting algorithms with more than four samples. However, when the phase shift calibration is inaccurate, these algorithms cannot eliminate the effects of nonsinusoidal characteristics.
K. Hibino +3 more
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Phase-shifting error and its elimination in phase-shifting digital holography
Optics Letters, 2002We investigate the influence of phase-shifting error on the quality of the reconstructed image in digital holography and propose a method of error elimination for a perfect image. In this method the summation of the intensity bit errors of the reconstructed image is taken as an evaluation function for an iterative algorithm to find the exact phase ...
Cheng-Shan, Guo +4 more
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Phase shift selection for two-step generalized phase-shifting interferometry
Applied Optics, 2011A phase shift selection method is proposed to design algorithms immune against phase shift errors in two-step generalized phase-shifting interferometry. A general formula for wavefront reconstruction error is derived, and its specific expressions for two common errors are also given.
Xiangfeng, Xu +5 more
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Iterative phase-shifting algorithm immune to random phase shifts and tilts
Applied Optics, 2013An iterative phase-shifting algorithm based on the least-squares principle is developed to overcome the random piston and tilt wavefront errors generated from the phase shifter. The algorithm iteratively calculates the phase distribution and the phase-shifting map to minimize the sum of squared errors in the interferograms.
Yi-Chun, Chen +3 more
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