Patent ID: 6667769
Filing Date: 2003-12-23
Classification: H04N

Abstract:
A time-integrating pixel sensor comprising:a photo-detector; a capacitive element electrically coupled to the photo-detector; a comparator element having a first input for receiving a reference voltage, a second input electrically coupled to the capacitive element and an output; a pixel data buffer responsive to the comparator output and operable to store a digital code value, a voltage reference supply element, electrically coupled to the first input of said comparator and operable to supply the reference voltage thereto; and a global code generator, coupled to said pixel data buffer and operable to supply the digital code value thereto; and a processor operably coupled to said pixel data buffer and operable to convert said digital code value to an optical power level, wherein said processor calculates the optical power level P in accordance with P=C&it;VrefN-N0,where C is a constant, Vref is the reference voltage, N is the digital code value stored in the pixel data buffer, and N0 is an initial digital code value.