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Updated: May 16, 2026

Micro/Nano-scale Strain Distribution Measurement from Sampling Moiré Fringes
Published on: May 23, 2017
Theoretical analysis for moiré effect of circular gratings for volume optical computerized tomography
Jia Wang1, Yang Song, Zhen-hua Li
1Department of Information Physics and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Abstract:
Obtaining the radial derivatives of wavefronts in projections is a critical step for volume optical computerized tomography. In this paper, the moiré effect of two identical circular gratings in acquiring the first-order radial derivative of a wavefront is analyzed. Based on scalar diffraction theory, the formation mechanism of circular gratings' moiré fringes is derived. A more explicit analytical relation between moiré fringes of different diffraction orders and tested wavefront is obtained. The involved results will be useful for extracting the projection information that is used in three-dimensional reconstruction by volume OCT.
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