Study on Single Pulse Measurement of Terminal Voltage Self-Coupled Laser Distance Sensor

Abstract

Previous research on distance sensors using the self-coupling effect of semiconductor lasers used current- spouting type LD driver circuits. As a result, the triangular current wave injected into the LD has poor linearity, requiring multiple triangular waves for measurement, which is time-consuming. We improved the triangular wave current’s linearity with a newly created current-absorbing LD drive circuit. We also proposed a novel signal processing method using a self-coupled signal obtained with a single triangular wave and experimentally confirmed that measurements performed with a single triangular wave have the same accuracy as conventional measurements using multiple pulses.