Dual-probe homodyne quadrature laser interferometer

Area of Science:

• Optics and Photonics
• Laser Interferometry
• Materials Science

Background:

• Accurate displacement measurement is crucial in various scientific and engineering fields.
• Traditional interferometers often require prior knowledge of wave propagation characteristics for specific applications.
• Developing versatile measurement tools is essential for advancing experimental capabilities.

Purpose of the Study:

• To present a novel dual-probe homodyne quadrature laser interferometer.
• To demonstrate its capability for simultaneous displacement measurements at two distinct spatial points.
• To showcase its application in locating laser-induced mechanical wave interaction sites without prior velocity information.

Main Methods:

• Implementation of a coupled homodyne interferometer design.
• Utilizing inverted polarity of probe signals for enhanced performance.
• Employing the dual-probe setup to analyze laser-induced mechanical wave propagation.

Main Results:

• The developed interferometer offers a wide dynamic range and constant sensitivity.
• Successful demonstration of measuring displacement at two separate locations.
• Accurate localization of pulsed-laser interaction sites on a plate was achieved without knowledge of wave propagation velocities.

Conclusions:

• The dual-probe homodyne quadrature laser interferometer is a robust tool for displacement sensing.
• This technique provides a novel method for non-contact, non-destructive analysis of localized impacts.
• The system's ability to function without prior wave speed data broadens its applicability in dynamic event analysis.