Results 151 to 160 of about 2,155 (180)

Simultaneous wavenumber measurement and coherence detection using temporal phase unwrapping

Applied Optics, 2012
Wavelength scanning interferometry and swept-source optical coherence tomography require accurate measurement of time-varying laser wavenumber changes. We describe here a method based on recording interferograms of multiple wedges to provide simultaneously high wavenumber resolution and immunity to the ambiguities caused by large wavenumber jumps.
A, Davila, J M, Huntley, C, Pallikarakis, P D, Ruiz, J M, Coupland   +4 more
openaire   +2 more sources

Innovative Compressive Sensing Algorithm for Multi-Temporal Differential Interferograms Phase Unwrapping

IGARSS 2023 - 2023 IEEE International Geoscience and Remote Sensing Symposium, 2023
In this paper, we present an innovative Phase Unwrapping (PhU) procedure for Multi Temporal DInSAR techniques, based on the Extended Minimum Cost Flow technique schema. The developed algorithm benefits from the Compressive Sensing (CS) theory. In particular, the procedure consists of the cascade of three steps.
Yasir Muhammad, Casu Francesco, De Luca Claudio, Lanari Riccardo, Onorato Giovanni, Manunta Michele   +5 more
openaire   +2 more sources

Quantitative phase microscopy: automated background leveling techniques and smart temporal phase unwrapping

Applied Optics, 2015
In order for time-dynamic quantitative phase microscopy to yield meaningful data to scientists, raw phase measurements must be converted to sequential time series that are consistently phase unwrapped with minimal residual background shape. Beyond the initial phase unwrapping, additional steps must be taken to convert the phase to time-meaningful data ...
Goldie, Goldstein, Katherine, Creath
openaire   +2 more sources

A New Method for Temporal Phase Unwrapping of Persistent Scatterers InSAR Time Series

IEEE Transactions on Geoscience and Remote Sensing, 2011
The analysis of radar time series with persistent scatterer techniques usually relies on temporal unwrapping, because phase behavior can be often described by simple models. However, one of the major limitations of temporal algorithms is that they do not take advantage of spatially correlated information. Here, we focus on two types of information that
MIGUEL Caro Cuenca, Andrew Hooper, Ramon F Hanssen   +2 more
exaly   +2 more sources

Bi-frequency temporal phase unwrapping using deep learning

Dimensional Optical Metrology and Inspection for Practical Applications VIII, 2019
In fringe projection profilometry (FPP), multi-frequency phase unwrapping, as a classical algorithm for temporal phase unwrapping (TPU), can eliminate the phase ambiguities and obtain the unwrapped phase with the aid of additional wrapped phase maps with different fringe periods.
Wei Yin, Chao Zuo, Shijie Feng, Tianyang Tao, Qian Chen   +4 more
openaire   +1 more source

Error-reduction methods for shape measurement by temporal phase unwrapping

Journal of the Optical Society of America A, 1997
Temporal phase unwrapping is a method of analyzing fringe patterns in which the fringe phase at each pixel is measured and unwrapped as a function of time t.
J. M. Huntley, H. O. Saldner
openaire   +1 more source

The Correction of Phase Unwrapping Errors in Sequences of Multi-Temporal Differential SAR Interferograms

IGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium, 2020
In this work, the theoretical foundations of a method to identify and routinely correct the phase unwrapping errors affecting a sequence of time-redundant sequence of differential SAR (DInSAR) interferograms are presented and discussed. Although the proposed method has principally been developed to work with differential SAR interferograms that form a ...
openaire   +3 more sources

InSAR coherence estimation for temporal analysis and phase unwrapping applications

IGARSS 2001. Scanning the Present and Resolving the Future. Proceedings. IEEE 2001 International Geoscience and Remote Sensing Symposium (Cat. No.01CH37217), 2002
In SAR interferometry, coherence between data acquisitions is potential information on the accuracy of interferograms. In this paper, a new coherence estimation approach is investigated. Our study is based on a binary mixture modelisation of coherence images. A Bayesian criteria is so used to discriminate between the two statistical mixed laws.
R. Abdelfattah, J.M. Nicolas, F. Tupin, B. Badredine   +3 more
openaire   +1 more source

Matched spatial-phase-shifting for the temporal-phase-unwrapping in electronic speckle pattern interferometry

Optik, 2001
Summary A synchronous combination spatial-carrier phase-shifting and temporal-phase-unwrapping techniques is proposed to reduce the frame acquisition time of the standard temporal phase unwrapping used in electronic speckle pattern interferometry. The proposed technique is robust against problems associated with the temporal phase shifting method ...
A Davila
exaly   +2 more sources

Optimal wavelength selection strategy in temporal phase unwrapping with projection distance minimization

Applied Optics, 2018
Micro Fourier transform profilometry (μFTP) is a recently developed computational framework for high-speed dynamic 3D shape measurement of transient scenes based on fringe projection. It has been demonstrated that by using high-frame-rate fringe projection hardware, μFTP can achieve accurate, denser, unambiguous, and motion-artifact-free 3D ...
Hui Li, Yan Hu, Tianyang Tao, Shijie Feng, Minliang Zhang, Yuzheng Zhang, Chao Zuo   +6 more
openaire   +2 more sources