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Updated: Jun 22, 2026
06:56
Micro/Nano-scale Strain Distribution Measurement from Sampling Moiré Fringes
Published on: May 23, 2017
Fringe patterns in integrated photoelasticity.
1Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia.
Summary
Rotation of principal stress axes significantly impacts integrated photoelasticity measurements. This effect reduces fringe distance and contrast in optical stress analysis, complicating stress distribution interpretations.
Area of Science:
- Solid Mechanics
- Optical Physics
- Materials Science
Background:
- Integrated photoelasticity uses fringe patterns to analyze stress distribution.
- Pointwise measurements determine stress but can be complex.
- Fringe patterns in circular polariscopes are influenced by stress integrals and axis rotation.
Purpose of the Study:
- To analyze the general effect of principal stress axis rotation in integrated photoelasticity.
- To understand how axis rotation influences recorded fringe patterns.
Main Methods:
- Theoretical analysis of integrated photoelasticity.
- Considering the general form of principal stress axis rotation.
Main Results:
- Principal stress axis rotation was analyzed in a general form.
- It was demonstrated that rotation diminishes the distance between interference fringes.
- The contrast of the fringe pattern is also diminished due to rotation.
Conclusions:
- Principal stress axis rotation is a critical factor affecting integrated photoelasticity.
- The observed reduction in fringe distance and contrast necessitates careful interpretation of stress data.
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