Related Experiment Video
Updated: Jan 8, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
22.4K
Single code pseudo-random quadrature phase shifting homodyne interferometry
Optics Express
|December 19, 2025
Summary
This study introduces a novel single-code modulation for digital homodyne interferometry, simplifying phase recovery. The new method achieves high optical sensitivity, advancing precision measurement techniques.
Area of Science:
- Optics and Photonics
- Signal Processing
Background:
- Traditional digital homodyne interferometry uses dual pseudo-random noise codes for quadrature phase shifting modulation.
- This enables simultaneous recovery of interference phase and time-of-flight range gating.
Purpose of the Study:
- To propose and validate a simplified
- single-code
- modulation scheme for digital homodyne interferometry.
- To retain the necessary 4-level phase step for double modulated homodyne detection.
Main Methods:
- Generation of a single m-sequence pseudo-random noise code for modulation.
- Numerical verification of the m-sequence autocorrelation profile preservation.
- Experimental characterization of phase recovery performance and relative intensity noise coupling.
Main Results:
- The single-code modulation scheme successfully retains the m-sequence autocorrelation profile.
- Experimental characterization confirmed effective phase recovery.
- An optical sensitivity of 3 µrad/√Hz was demonstrated.
Conclusions:
- The proposed single-code modulation scheme simplifies digital homodyne interferometry.
- It maintains performance while reducing complexity.
- This advancement offers potential for more efficient and sensitive optical measurement systems.
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