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Related Experiment Video

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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators

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Published on: May 30, 2014

Phase-shifting interferometry with feedback control using heterodyne phase detection.

Youichi Bitou¹

¹National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Central, Ibaraki, Japan. y-bitou@aist.go.jp

|August 19, 2008

Summary

A novel phase-shifting interferometer utilizes heterodyne phase detection for precise feedback control. This system successfully stabilizes interference fringes and achieves accurate phase shifts even amidst significant vibrations.

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Area of Science:

Optical Metrology
Interferometry
Instrumentation

Background:

Phase-shifting interferometry is crucial for high-precision measurements.
External vibrations can degrade the accuracy of interferometric systems.
Effective feedback control is necessary for robust interferometric performance.

Purpose of the Study:

To develop a phase-shifting interferometer with advanced feedback control.
To propose a composite heterodyne phase detection method for feedback signal acquisition.
To demonstrate the system's capability in stabilizing interference fringes and achieving accurate phase shifts.

Main Methods:

Development of a phase-shifting interferometer incorporating feedback control.
Implementation of a composite heterodyne phase detection technique.
Utilizing a digital high-speed lock-in amplifier for signal processing.

Main Results:

Successful demonstration of interference fringe stabilization.
Achievement of accurate pi/2 phase shifts.
Effective performance demonstrated under micrometer-order vibrations.

Conclusions:

The developed phase-shifting interferometer with heterodyne feedback control enhances measurement stability.
The composite heterodyne detection method provides reliable feedback signals.
The system offers robust performance in vibration-prone environments.