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Interferometric measurement of angular motion
Fabián Erasmo Peña Arellano1, Hasnain Panjwani, Ludovico Carbone
1School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, United Kingdom. fepa@star.sr.bham.ac.uk
The Review of Scientific Instruments
|May 3, 2013
Summary
This study presents a novel homodyne polarization interferometer for precise angular motion measurement. The compact device achieves high accuracy and a wide measurement range using optimized cat
Area of Science:
- Optical Engineering
- Precision Measurement
- Interferometry
Background:
- Accurate angular motion measurement is critical in various scientific and industrial applications.
- Existing interferometers often face limitations in range, alignment, or compactness.
Purpose of the Study:
- To design and realize a homodyne polarization interferometer for enhanced angular motion measurement.
- To optimize cat's eye retroreflectors for maximizing measurable range and simplifying alignment.
- To evaluate the performance and linearity of the developed interferometer.
Main Methods:
- Optical design and numerical characterization of cat's eye retroreflectors using Zemax software.
- Calculation of measurement linearity considering optical aberrations.
- Construction of a compact interferometer using stock components.
- Performance evaluation against a commercial autocollimator.
Main Results:
- The interferometer demonstrates high reproducibility (within 0.1%) and excellent linearity (less than 1 ppm).
- Achieved a sensitivity limit of approximately 5 × 10(-11) rad/Hz in the audioband down to 100 mHz.
- Exhibits a wide angular measurement range exceeding ±1°.
Conclusions:
- The developed homodyne polarization interferometer offers a compact, high-performance solution for angular motion measurement.
- Optimized retroreflectors and a robust design contribute to its superior accuracy and range.
- This instrument is suitable for applications demanding precise angular sensing.
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