Active-mode CAOS camera demonstration

Abstract

For the first time, demonstrated is the active-mode CAOS (i.e., Coded Access Optical Sensor) camera. The design demonstrated uses a hybrid approach to both optical device engagement and time-frequency CAOS mode operations. Specifically, time-frequency modulation of both the target illumination light source and the Digital Micromirror Device (DMD) combine to deliver the Frequency Modulation (FM)-Code Division Multiple Access (CDMA) mode of the CAOS camera. Using a 39.6 Klux white light 32 kHz FM LED source combined with a 1 kHz bit rate 4096 bits Walsh sequence CDMA code via the DMD, achieved is 58 × 70 CAOS pixels near 60 dB linear Dynamic Range (DR) imaging of a 36 patch calibrated high DR white light target. Applications for the active-mode CAOS camera are numerous and include indoor full spectrum food inspection and photography where a linear DR camera can play an important role for accurate analysis and color image recovery.