Optical sensor for, e.g. passenger car, has circuit unit that evaluates change of speckle or granulation patterns between signals from detector and determines information about change of object from change of patterns

摘要

The optical sensor (1) has a light source (21) which emits coherent light with respect to an object, where a portion of the light is reflected from the object or scattered. A detector (14) receives the reflected or scattered light, and generates and transmits digital signal to circuit unit. The circuit unit evaluates the change of speckle or granulation patterns between two signals and determines the information about the change of object in space from the change of speckle or granulation patterns. An independent claim is included for method for measuring movement or length of object.