Patent ID: 6765676
Filing Date: 2004-07-20
Classification: G01N

Abstract:
A method for simultaneously compensating a source drift of a light source and a detector drift of a light detector, said method comprising:a) providing a first beam path with a crossing for a probe beam traveling from said light source to said light detector along a test location; b) providing a second beam path from said light source to said light detector along said crossing and not along said test location; c) positioning at said test location a calibration sample for sending a known response beam along said first beam path to said light detector in response to said probe bean; d) calibrating said light source and said light detector using said known response beam; e) temporarily placing a reference sample at said beam crossing for sending a reference beam along said second beam path to said light detector in response to said probe f) establishing a relation between said known response beam and said reference beam; g) defining a group of operational calibration parameters including a set time period, drift of said light source or drift of said light detector; h) positioning at said test location a test sample and testing said test sample; i) interrupting said testing in conjunction with said operational calibration parameters and temporarily placing said reference sample at said beam crossing for simultaneously compensating said source drift and said detector drift using said established relation while said test sample remains in position.