Analog-to-digital converters for optical sensor arrays

The use of CMOS technology allows the monolithic integration of photosensor arrays together with analog-to-digital (A/D) conversion circuits. The structure of the array can be exploited to increase the connectivity between the sensor and the converter, which are in close coupling. Both single-converter per array and multiple-converter per array approaches are therefore possible. This paper presents a comparative study of different A/D conversion architectures incorporated in intelligent optical systems. The presented schemes have been validated by experimental evaluations.