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High-Precision Measurement Method for Small Angles Based on the Defect Spot Mode of the Position-Sensitive Detector
Yusheng Zhai1, Guorong Wang1, Yiheng Zhao1
1School of Electronics and Information, Zhengzhou University of Light Industry, Zhengzhou 450000, China.
Sensors (Basel, Switzerland)
|November 27, 2024
Summary
This study introduces a novel small-angle measurement technique using a position-sensitive detector (PSD) in defect spot mode. The method significantly enhances measurement sensitivity and real-time performance for precision applications.
Area of Science:
- Optoelectronics
- Precision Metrology
Background:
- Accurate small-angle measurement is crucial for various scientific and industrial applications.
- Existing methods using position-sensitive detectors (PSDs) have limitations in sensitivity.
Purpose of the Study:
- To propose and verify a novel small-angle measurement method.
- To significantly improve measurement sensitivity compared to existing PSD-based techniques.
Main Methods:
- Utilizing the defect spot mode of a position-sensitive detector (PSD).
- Leveraging the output characteristics of the PSD and focused beam properties.
- Conducting calibration experiments with a piezoelectric transducer (PZT).
Main Results:
- Achieved a 57-fold improvement in small-angle measurement sensitivity compared to the autocollimation method.
- Demonstrated potential for further sensitivity enhancement through system parameter optimization.
- The proposed method exhibits a simple system design and high real-time capability.
Conclusions:
- The novel PSD-based method offers a substantial advancement in small-angle measurement sensitivity.
- The technique is suitable for high-precision motion error detection and shape/position measurement.
- Further optimization can lead to even greater measurement precision.
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