Laser dynamics in sawtooth-like self-mixing signals

Area of Science:

• Optics and Photonics
• Laser Physics
• Metrology

Background:

• Self-mixing interferometry is a technique utilizing laser feedback.
• Understanding transient phenomena in self-mixing signals is crucial for advanced applications.
• Extracting target properties from optical signals requires robust models.

Purpose of the Study:

• To experimentally demonstrate that transient phenomena in self-mixing signals contain target reflectivity and distance information.
• To develop and validate a dynamical model for explaining these transient phenomena.
• To establish a method for determining target properties from measured self-mixing signals.

Main Methods:

• Experimental setup for generating and measuring self-mixing signals from a moving target.
• Development of a dynamical model for laser diode behavior under self-mixing conditions.
• Signal processing techniques to analyze high-bandwidth self-mixing data.

Main Results:

• Transient phenomena in self-mixing signals were experimentally observed and characterized.
• The dynamical laser diode model successfully explained the observed transient phenomena.
• A method was developed to derive target reflectivity and distance from the transient signals.

Conclusions:

• Transient phenomena in laser self-mixing signals are valuable indicators of target properties.
• The dynamical laser diode model provides a robust framework for analyzing these signals.
• This work enables precise measurement of target reflectivity and distance using self-mixing interferometry.