CMOS digital image sensor system and method

Abstract

An image sensor system comprises an array of pixels. Each of these pixels includes a light sensitive element that generates a pixel signal that is indicative of the amount of light received by that pixel. A comparator then compares the pixel signal to a reference signal and generates a strobe signal in response to this comparison, while a global counter generates a count across a shutter period. Finally, an array of memory elements is provided. Each of these memory elements stores a count from the global counter in response to receiving the strobe signal from the corresponding pixel of the array of pixels. As a result, the array of pixels has relatively little logic functionality. Each pixel need only contain the light sensitive element and the comparator. Thus, the system can provide a good fill factor. Further, the global counter can be shared across the entire memory array. It is most applicable to implementation in CMOS technology.

Dependencies are inferred from the claim text.