Patent ID: 9236943
Filing Date: 2016-01-12
CPC Classification: G01J,G01S,H04B,H04N

Claim Text:
1. A method of eliminating an offset in a spot centroid due to crosstalk, comprising: measuring crosstalk ratios between respective pixels of a detector by a crosstalk-ratio measuring device; arranging the crosstalk ratios between the respective pixels into a crosstalk matrix characterizing crosstalk characteristics of the detector; left-multiplying signals outputted from the detector by an inverse matrix of the crosstalk matrix to derive a light-intensity-distribution signal with impacts of the crosstalk substantially removed; and calculating the spot centroid based on the light-intensity-distribution signal, wherein the crosstalk-ratio measuring device comprises: a parallel-light source configured to emit parallel light beams; a two-dimensionally adjustable reflector configured to reflect the parallel light beams from the parallel-light source; a reflector configured to further reflect the light beams reflected by the two-dimensionally adjustable reflector; an imaging lens configured to converge the light beams reflected by the reflector onto the multi-pixel spot-centroid detector to form a spot thereon; a computer configured to record signals outputted from the multi-pixel spot-centroid detector; and wherein measuring the crosstalk ratios comprises: arranging the crosstalk ratios into the crosstalk matrix comprises:  wherein an element c wherein measuring the crosstalk ratios comprises: