Monolithically integrated optical displacement sensorin GaAs/AlGaAs

Abstract
A monolithically integrated displacement sensor has been fabricated in the GaAs/AlGaAs material system. The device is configured as a Michelson interferometer and consists of a DBR laser, a directional coupler, transparent waveguides and a photodetector. Interference fringes could be seen at a measurement distance of up to 45 cm, requiring only the alignment of an external GRIN lens for beam collimation.