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Updated: Jun 16, 2026
06:56
Micro/Nano-scale Strain Distribution Measurement from Sampling Moiré Fringes
Published on: May 23, 2017
Geometric parameters of moiré fringes.
Applied Optics
|February 19, 2010
Summary
This study analyzes the moiré phenomenon under incoherent illumination between periodic and quasiperiodic structures using spatial frequency analysis. The new method precisely explains fringe parameters without system averaging effects.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Moiré patterns are typically analyzed considering system averaging effects.
- Understanding moiré phenomena in quasiperiodic structures is crucial for advanced optical applications.
Purpose of the Study:
- To analyze the incoherent illumination moiré phenomenon between periodic and quasiperiodic structures.
- To develop a method that explains fringe parameters without considering the averaging effect of the detecting system.
Main Methods:
- Spatial frequency analysis of the resultant transmittance.
- Derivation of the basic moiré pattern equation from the beat phenomenon.
- Derivation of fringe profile, spacing, orientation, and displacement equations.
Main Results:
- A fundamental equation for moiré patterns under incoherent illumination was obtained, exclusively from the beat phenomenon.
- Equations for moiré fringe shape, spacing, orientation, and local displacement were derived.
- Experimental verification of the fringe profile equation was achieved.
Conclusions:
- The spatial frequency analysis provides a comprehensive explanation of moiré fringe parameters without system averaging.
- The derived equations accurately describe moiré fringe characteristics and enable interpretation of sensitivity enhancement techniques like fringe multiplication.
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