Dual-wavelength in-line phase-shifting interferometry based on two dc-term-suppressed intensities with a special phase shift for quantitative phase extraction

2016 ◽  
Vol 41 (11) ◽  
pp. 2430 ◽  
Author(s):  
Xiaoqing Xu ◽  
Yawei Wang ◽  
Yuanyuan Xu ◽  
Weifeng Jin
Keyword(s):  
Phase Shift ◽  
Phase Shifting ◽  
Dual Wavelength ◽  
Phase Extraction ◽  
Quantitative Phase ◽  
Phase Shifting Interferometry

Phase Shift Extraction Algorithm by Special Points in Two-Step Generalized Phase-Shifting Interferometry

2016 ◽  
Vol 43 (5) ◽  
pp. 0508004
Author(s):  
周志盛 Zhou Zhisheng ◽  
董玉明 Dong Yuming ◽  
章逸舟 Zhang Yizhou ◽  
焦国华 Jiao Guohua ◽  
鲁远甫 Lu Yuanfu ◽  
...  
Keyword(s):  
Phase Shift ◽  
Phase Shifting ◽  
Phase Shifting Interferometry ◽  
Extraction Algorithm ◽  
Special Points

Effect of Phase Error in Phase-Shifting Interferometer

2019 ◽  
Vol 888 ◽  
pp. 11-16 ◽  
Author(s):  
Yoshitaka Takahashi
Keyword(s):  
Phase Shift ◽  
Measurement Errors ◽  
Phase Error ◽  
Optical Path Length ◽  
High Accuracy ◽  
Optical Path ◽  
Phase Shifting ◽  
Optical Source ◽  
Phase Shifting Interferometry ◽  
Phase Shift Error

Phase-shifting interferometry is widely used because it can measure phase with high accuracy. Changing optical path length with a PZT transducer and changing frequency of the optical source with a laser diode (LD) are two common methods to apply the desired phase shift between the arms in the interferometer. In any case, however, it is not easy to apply the desired shift accurately, and if not, measurement errors occur. In order to reduce the errors, the effect of the phase shift error has been analyzed numerically especially in the case with LD.

Determination of Phase Shift by Digital Holography

2019 ◽  
Vol 888 ◽  
pp. 43-46
Author(s):  
Yoshitaka Takahashi ◽  
Masatoshi Saito ◽  
Toru Nakajima ◽  
Masakazu Shingu
Keyword(s):  
Phase Shift ◽  
Noise Reduction ◽  
Digital Holography ◽  
High Accuracy ◽  
Measured Data ◽  
Phase Shifting ◽  
Surface Shape ◽  
Shape Measurement ◽  
Phase Shifting Interferometry

In phase shifting interferometry phase shift is applied by various ways, but applying it with high accuracy, especially by LD current modulation, is not easy. In order to determine the accurate phase shift a new method has been proposed that the value of LD current corresponding to π/2 phase shift can be determined by phase shifting digital holography. The measured data of standard in surface shape measurement were used for calibration, and the obtained value was confirmed to cause noise reduction and improvement of holographic reconstructed images in digital holography.

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