Patent ID: 8345260
Filing Date: 2013-01-01
Classification: G01B,G01Q

Abstract:
1. A method of detecting a movement of a measuring probe provided between an objective lens adapted to image an object plane on a predetermined image plane and said object plane, comprising: splitting an input beam of light into a measurement beam and a reference beam; focusing said measurement beam to a point lying in a reverse focal plane of said objective lens such that said measurement beam is collimated by said objective lens; reflecting said collimated measurement beam at said measuring probe, said reflected measurement beam being directed towards said objective lens such that said objective lens focuses said reflected measurement beam to a point lying in said reverse focal plane; collimating said reflected measurement beam; superimposing said collimated reflected measurement beam and said reference beam to form a superimposed beam; and detecting an interference between said reflected measurement beam and said reference beam.