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A generalized temporal phase unwrapping algorithm for three-dimensional profilometry
Optics and Lasers in Engineering, 2008A generalized temporal phase unwrapping algorithm is proposed for absolute phase measurement of object surfaces with complex topography. We first make comments on error analysis of various temporal phase unwrapping (TPU) algorithms and point out problems existing in these techniques.
Jindong Tian, Xiang Peng
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Phase invalidity identification framework with the temporal phase unwrapping method
Measurement Science and Technology, 2011Phase retrieval from fringe patterns is widely used in optical metrology. In profilometry for example, precise phase values allow three-dimensional coordinate data with higher accuracy to be determined. The phase-shifting method coupled with temporal phase unwrapping provides not only the unwrapped phase, but also gives the modulation map, root mean ...
Lei Huang, Anand Krishna Asundi
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A generalized multi-sensitivity temporal phase unwrapping method for absolute phase retrieval
Optics and Laser Technology, 2017Abstract In this paper, a noble phase unwrapping method based on 2-sensitivity temporal phase unwrapping (TPU) is proposed. The algorithm considers the maximum ratio between two wavelengths in a measurement system and deals with wrapped phase error in detail.
Chenggen Quan, C J Tay
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A temporal phase unwrapping algorithm for photoelastic stress analysis
Optics and Lasers in Engineering, 2007Photoelastic stress analysis is a full-field optical technique for experimental stress analysis whose automation has received considerable research attention over the last 15 years. The latest developments have been made possible largely due to the availability of powerful calculators with large memory capacity and colour, high resolution, cameras.
Antonio Baldi
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Temporal phase unwrapping for cine velocity imaging
Journal of Magnetic Resonance Imaging, 1995AbstractA simple algorithm named temporal phase unwrapping (TPU) is introduced to address the phase aliasing problem in time‐dependent pa contrast (CINE‐PC) velocity imaging. The method exploits the temporal continuity of velocity field and unwraps the phmc along time. TPU only involver a one‐dimensional (1D) temporal integration: therefore.
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Temporal phase unwrapping: application to surface profiling of discontinuous objects
Applied Optics, 1997The recently proposed technique of temporal phase unwrapping has been used to analyze the phase maps from a projected-fringe phase-shifting surface profilometer. A sequence of maps is acquired while the fringe pitch is changed; the phase at each pixel is then unwrapped over time independently of the other pixels in the image to provide an absolute ...
H O, Saldner, J M, Huntley
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Using temporal phase-unwrapping mask for shape measurement
SPIE Proceedings, 2002A new phase unwrapping algorithm is proposed based on temporal phase unwrappping. Given a series of wrapped phase maps generated from different fringe periods, a jump mask (or matrix) was introduced which reveal the 2π phase jump between successive levels.
Yuchi Lin +5 more
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Structured light fields 3d imaging with temporal phase unwrapping
Optical Metrology and Inspection for Industrial Applications VII, 2020The passive depth map recovery based on light field data always suffers from low accuracy and high computational burden due to the noise in sub-aperture images and the narrow disparity between sub-aperture views. To overcome this problem, in this paper, temporal digital fringe projections are used to guide the accurate depth map recovery with light ...
Yate Jiang +3 more
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Temporal phase unwrapping and its application in shearography systems
Applied Optics, 1998Temporal phase unwrapping is applied to a two-camera polarization phase-stepped system. A simple algorithm for the phase-change calculation is given, together with simulations, to indicate its validity and strength. This method can be applied directly for detection of phase changes as a function of time.
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