Patent ID: 7663737

Claim:
A sensor device comprising a source for electromagnetic radiation, a plurality of receivers for the electromagnetic radiation, and an electronics unit, wherein the electronics unit transmits electromagnetic radiation from the electromagnetic source and the plurality of receivers receive electromagnetic radiation reflected from a reflection surface of an object to determine a distance which the electromagnetic radiation emitted from the source travels from the reflection surface of the object to the respective receiver by evaluation of at least one of the delay time of the electromagnetic radiation and the phase of an oscillation modulated on to the electromagnetic radiation, wherein each of the plurality of receivers is evaluated individually, the electronics unit detects reflective objects, which are like floating parts and are distributed in three dimensions in a medium, by determining from the measured distances a first group of distances which fit a predetermined distribution and the sensor device emits a signal which is associated with the detection of reflective objects which are like floating parts when the first group of distances contains more than one group member.