SELF-MIXING LASER SENSOR

摘要

A laser sensor is used as a velocimeter using principles of self-mixing. A laser device having an optical cavity with an optical output face and a beam splitter integrated into the laser device provides at least two output beams from the optical output facet. A first one of the output beams is used as a probe beam directed to a target surface external to the sensor and a second one of the output beams is used as a monitor beam directed to an optical detector which measures the laser output power. From the measured output power, motion of the target surface relative to the sensor is determined as a function of self-mixing of a portion of the probe beam returned to the optical cavity by reflection from the target surface.