Patent ID: 6433329
Filing Date: 2002-08-13
Classification: G01J

Abstract:
Apparatus for dynamically updating a detection threshold for an optical sensor adapted to compare a light-detector output with said detection threshold to determine a logic signal indicative of a first state, wherein a high light intensity is sensed by a light detector, and a second state, wherein a low light intensity is sensed by the light detector, said apparatus comprising:a first part of an electronic circuit programmed to record a first output of said light detector when the high light intensity is sensed by the light detector and a second output of the light detector when the low light intensity is sensed by the light detector; and a second part of the electronic circuit programmed to update the detection threshold as a function of said first and second outputs of the light detector; wherein said first and second outputs of the light detector correspond to maximum and minimum light intensities sensed by the light detector.