Patent ID: 8031260
Filing Date: 2011-10-04
Classification: H04N

Abstract:
1. An active pixel sensor comprising: at least one pixel comprising a photodetector that outputs an output level indicative of incoming light; a sample and hold element electrically connected to the at least one pixel operating to store a signal output level of the at least one pixel during a readout operation; an adjusted saturated voltage source, comprising a node which provides an adjusted saturation voltage; and a comparator having a first input node operatively connected to the sample and hold element, a second input node electrically connected to the adjusted saturation voltage node, and an output node, said comparator operating to output a signal indicating whether the adjusted saturation voltage exceeds the output level from the photodetector, wherein said signal output from said comparator triggers replacement of a pixel value derived from said signal output level of the at least one pixel with a maximum pixel value when the adjusted saturation voltage exceeds the output level from the photodetector.