Patent ID: 8836955
Filing Date: 2014-09-16
Classification: G01B,G01S

Abstract:
1. A device for measuring positions of plural surface areas of a surface, comprising: a light source for generating a sequence of light pulses with a repetition rate; a light directing device which is controllable to direct said sequence of light pulses onto a surface area of said surface which can be selected from plural surface areas; a detector arrangement comprising a plurality of detectors configured to receive a plurality of return light signals scattered and/or reflected by said surface area into different directions; and an evaluation circuit coupled to said detector arrangement and configured, for determining a position of said surface area, to determine, for each return light signal of said plurality of return light signals received by said detector arrangement, a phase difference between a reference signal derived from said sequence of light pulses and a return signal component of said return light signal, said return signal component respectively having a first frequency which corresponds to a first multiple of said repetition rate.