An Optical Source for Characterizing CMOS Imagers: Characterization and Calibration Results

Salt Lake Community College

Characterizing the optical properties of CMOS im- agers requires a source of illumination. This paper presents the characterization and calibration of an op- tical source which consists of an array of light emitting diodes, an infrared cut-o® ¯lter, and di®using lenses{ all of which are encased in an anodized aluminium housing. The characterization and calibration results of the optical source are presented in detail. The opti- cal source is capable of illuminating a 15 mm ¯eld at a conjugate distance of 50 mm with 98 percent unifor- mity. The spatial uniformity of the source is compared with with an integrating sphere an Optoliner projection system. From the characterization and comparison re- sults, it is concluded that the optical source system is capable of characterizing CMOS imagers.