A miniaturized VCSEL based sensor platform for velocity measurement

There are many applications for contactless measurement of the displacement and velocity of moving objects. Philips has developed an optical displacement sensor that can be compared to expensive laser-inteferometry sensors however at a cost compatible with requirements for consumer products. In the paper the design and performance of the miniaturized and highly integrated sensor are discussed. The sensor is based on the laser self mixing effect. The small form factor of less than 0.2 cubic centimeters allows applications previously considered impossible.