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Published on: September 30, 2019
Modified Fabry-Perot interferometer for displacement measurement in ultra large measuring range
Chung-Ping Chang1, Pi-Cheng Tung, Lih-Horng Shyu
1Department of Mechanical Engineering, National Central University, Taoyuan 32001, Taiwan.
The Review of Scientific Instruments
|June 8, 2013
Summary
A novel common-optical-path interferometer achieves picometer resolution and a large 500 mm measurement range. This system minimizes environmental errors for precise industrial length measurements.
Area of Science:
- Optomechatronics
- Precision Metrology
Background:
- Laser interferometers offer high precision but are susceptible to environmental errors in non-common-optical-path designs.
- In situ industrial applications are limited by measurement inaccuracies under ordinary conditions.
Purpose of the Study:
- To develop a novel interferometric displacement measuring system with a common-optical-path structure.
- To enhance resistance to tilt-angle and minimize environmental and mechanical effects for industrial applications.
Main Methods:
- Integration of optomechatronic modules for picometer-order resolution.
- Implementation of an automatic gain control module for signal stabilization.
- Employment of a self-developed interpolation model to enhance resolution.
Main Results:
- Achieved a resolution of 2.5 nm within a 500 mm measuring range.
- Maximal standard deviation of 0.146 μm compared to a commercial Michelson interferometer over 500 mm.
- Demonstrated simultaneous high resolution and ultra-large measuring range.
Conclusions:
- The proposed common-optical-path Fabry-Perot interferometer offers superior performance.
- This system provides the largest dynamic measurement range reported for a Fabry-Perot interferometer.
- The design minimizes environmental influences, enabling precise in situ industrial measurements.
