Universal optical setup for phase-shifting and spatial-carrier digital speckle pattern interferometry

Abstract

Background: Digital speckle pattern interferometry (DSPI) is a competitive optical tool for full-field deformation measurement. The two main types of DSPI, phase-shifting DSPI (PS-DSPI) and spatial-carrier DSPI (SC-DSPI), are distinguished by their unique optical setups and methods of phase determination. Each DSPI type has its limited ability in practical applications. Results: We designed a universal optical setup that is suitable for both PS-DSPI and SC-DSPI, with the aim of integrating their respective advantages, including PS-DSPI's precise measurement and SC-DSPI's synchronous measurement, improving DSPI's measuring capacity in engineering. Conclusion: The proposed setup also has several other advantages, including a simple and robust structure, easy adjustment and operation, and versatility of measuring approach.

Precise Detection of Wrist Pulse Using Digital Speckle Pattern Interferometry

“…DSPI is classified, based on their optical setups and phase determination methods, into phase-shifting DSPI (PS-DSPI) and spatial-carrier DSPI (SC-DSPI) [ 20 ]. The SC-DSPI is also known as digital holographic interferometry [ 21 ].…”

Precision roll angle measurement based on digital speckle pattern interferometry

“…Their reflected light was collected by the instrument, resulting in the speckle interference. Aided by the fourbucket phaseshifting technique [32], the phase distribution was determined by the comprehensive calculation of four phasemodulated speckle interferograms. The distribution of the phase difference was subsequently obtained by subtracting the phase distribution before loading from it after loading.…”

“…If the change of optical path difference is not the same on the entire sur face, a distribution of the phase difference is obtained and further processed to evaluate the inplane deformation. The phase maps before and after the object motion are quantita tively determined by carrying out the phaseshifting technique which is performed by using a piezoelectric transducer (PZT) driven mirror in the system [32].…”

Fast phase denoising using stationary wavelet transform in speckle pattern interferometry

“…Speckle pattern interferometry records the speckle field produced by the interference between the reference and object beams diffused from a rough surface and calculates the slight surface deformation after the phase change between the speckle fields before and after additive loading is loaded [1][2][3]. It is widely used in engineering measurements such as strain determination, 3D deformation measurement and vibration evaluation due to its full-field, non-contact and highresolution advantages [4,5].…”