Patent ID: 6763153
Filing Date: 2004-07-13
Classification: G01C,G01D

Abstract:
An optical sensor system for producing a sensor signal having reduced noise, comprising:an optical sensor adapted to receive a sensor input light and adapted to measure a physical quantity, with the optical sensor producing a sensor output signal corresponding to the physical quantity and a first noise component; a first detector which detects the sensor output signal; a second detector which detects the sensor input light corresponding to a second noise component; a high pass filter or DC block coupled to the second detector; a filter, with a group delay substantially corresponding to a time delay of the sensor input light traversing the optical sensor, coupled to the high pass filter or DC block, a multiplier, which multiplies the filtered time-delayed second noise component with the sensor output signal, and a subtractor which subtracts the multiplied filtered time-delayed second noise component from the sensor output signal to produce the sensor signal having the reduced noise.