Real-time displacement reconstruction by an orthogonal Fabry-Perot interferometer

Area of Science:

• Optics and Photonics
• Metrology
• Vibration Analysis

Background:

• Accurate real-time displacement measurement is crucial for various scientific and engineering applications.
• Traditional methods may face limitations in speed, accuracy, or directional discrimination.

Purpose of the Study:

• To develop and demonstrate a real-time displacement reconstruction method.
• To achieve high-precision measurement of vibration target displacement.
• To enable directional discrimination of motion.

Main Methods:

• Utilizing an orthogonal Fabry-Perot interferometer.
• Generating two orthogonal polarization signals with a phase shift of π/2 using a He-Ne laser.
• Employing arctangent and unwrapping algorithms for real-time displacement reconstruction.
• Leveraging quadrature signals for motion direction discrimination.

Main Results:

• Successful real-time reconstruction of target displacement.
• Experimental validation with varying peak-to-peak amplitudes and frequencies.
• Demonstrated reconstruction errors consistently below 58 nm.
• Effective discrimination of motion direction using quadrature signals.

Conclusions:

• The presented orthogonal Fabry-Perot interferometer method enables accurate and real-time displacement reconstruction.
• The technique is robust across different vibration parameters.
• This method offers a reliable solution for precise vibration analysis and metrology.