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Micro/Nano-scale Strain Distribution Measurement from Sampling Moiré Fringes
Published on: May 23, 2017
Focusing errors in a collimating lens or mirror: use of a moiré technique
Applied Optics
|February 4, 2010
Summary
Fresnel diffraction creates grating images. Superposing a second grating forms moiré patterns sensitive to beam parallelism, enabling study of collimating lens and mirror focusing errors.
Area of Science:
- Optics
- Diffraction Physics
Background:
- Fresnel diffraction patterns can reproduce gratings.
- Moiré patterns arise from superposing gratings.
Purpose of the Study:
- Investigate using moiré patterns for optical focusing error analysis.
- Explore sensitivity of moiré patterns to incident beam parallelism.
Main Methods:
- Generating Fresnel diffraction patterns of a grating.
- Superposing a second grating onto the diffraction image.
- Analyzing the resultant moiré pattern.
Main Results:
- Moiré pattern formation is dependent on the parallelism of the incident beam.
- The technique shows potential for detecting focusing errors.
Conclusions:
- Moiré pattern analysis of Fresnel diffraction offers a novel method for assessing optical system focusing.
- This technique can be applied to evaluate collimating lenses and mirrors.
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