A smart image sensor with high-speed feeble ID-beacon detection for augmented reality system

In this paper, we present a smart image sensor with high-speed feeble ID-beacon detection for an augmented reality (AR) system. AR systems are designed to provide an enhanced view of the real world with meaningful information from a computer. Our target AR system uses an optical device with ID beacon such as a blinking LED. Our sensor architecture realizes analog readout for 2-D image capture and high-speed digital readout for ID beacon detection simultaneously. The pixel circuit has a logarithmic-response photo detector and an adaptive modulation amplifier to detect a feeble ID beacon in wide range of background illumination. A 128 /spl times/ 128 smart sensor has been developed and successfully tested. It achieves 4850 bit/IC/spl middot/sec using 40 kHz carrier and < -10.0 dB signal-to-background ratio (SBR) in > 40 dB background illumination for robust ID-beacon detection.