Amplitude modulation ranging achieved by self-sweeping fiber laser in a short distance

Abstract

A self-sweeping fiber laser ranging system was proposed and experimentally studied, which proved the capability of distance measurement based on the continuous wave self-sweeping pulse. Thanks to the beat-frequency signal exists in the process of central wavelength switchover, self-sweeping laser can generate amplitude modulation light without any extra active modulators. Therefore, the phase difference in laser flight times between the reference light and the reflected light can be extracted from the time domain. In experiment, we measured the phase difference and calculated the distance from different spatial lengths less than 25 cm, and the results were analyzed based on the baseline result acquired from an interferometry method. Endowing laser ranging with self-sweeping laser creates a platform that combines the individual advantages of the traditional ways of ranging, which show a promising accuracy and the ability to cross scenes.