ABSOLUTE DISTANCE AND VELOCITY-MEASUREMENTS BY THE FMCW TECHNIQUE ANDSELF-MIXING INTERFERENCE EFFECT INSIDE A SINGLE-MODE ND-YAG-LITAO3 MICROCHIP LASER

In this paper, a theoretical analysis of a sensor which uses a self-mi xing interference effect inside a microchip laser is reported. Experim entally, the FMCW approach has been implemented by using both a Nd:YAG microchip laser emitting at 1.064 mu m and an intracavity LiTaO3 crys tal. By using the Pockel effect a total 10 GHz shift of the optical wa ve has been obtained by applying a transverse electrical field inside the LiTaO3 crystal. We demonstrated that the dynamics of the microchip laser can be used to perform highly sensitive preamplified detection for absolute distance and velocity measurements from 1 to 10 m +/- 5 m m and from 0.1 to 25 m s(-1) +/- 1.5%, respectively.