Quasi-Common-Path Laser Feedback Interferometers for Precision Measurement of Non-Cooperative Targets

X.J. Wan; Shu Lian Zhang

doi:10.4028/www.scientific.net/KEM.381-382.49

Paper Titles

AFM with the Slope Compensation Technique for High-Speed Precision Measurement of Micro-Structured Surfaces
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Compact Displacement Measurement System Based on Microchip Nd:YAG Laser with Birefringence External Cavity
p.39

New Synthetic Heterodyne Laser Doppler Vibrometer for Measurement of Mechanical Vibrations with Submicron Amplitude
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Development of the Precision Stage with Nanometer Accuracy and a Millimeter Dynamic Range
p.47

Quasi-Common-Path Laser Feedback Interferometers for Precision Measurement of Non-Cooperative Targets
p.49

Self-Mixing Interferometer Based on Four-Bucket Integration Technique for Micro-Displacement Measurement
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Micro-Nanometer Positioning Control of Bimodal Ultrasonic Motor Based on Wavelet Differential Actuation Pattern
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Adaptive Fiber-Optical Sensor System for Pico-Strain and Nano-Displacement Metrology
p.61

The Development of a Separated Mini-Environment
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HomeKey Engineering MaterialsKey Engineering Materials Vols. 381-382Quasi-Common-Path Laser Feedback Interferometers...

Quasi-Common-Path Laser Feedback Interferometers for Precision Measurement of Non-Cooperative Targets

Abstract:

In this paper, we report a novel quasi-common-path laser feedback interferometer (QLFI) for highly stable, high-resolution and non-contact displacement measurement. QLFI measures the displacement of the target by measuring the phase of feedback light. In addition to the target-generated feedback light (frequency shifted by 2#), a reference mirror generates a reference feedback light which is frequency shifted by #. The phase variations of both feedback lights are measured by heterodyne detection simultaneously and their difference offers the phase variations caused only by target displacement. When the optical path lengths of the reference and measuring feedback light are nearly the same, the phase fluctuations caused by the environment and laser instability are effectively removed. The heat-induced deformation of a He-Ne laser tube is successfully in-line measured using QLFI.