PIN-diode based optical distance measurement sensor for low optical power active illumination

Based on the time-of-flight principle an optoelectronic integrated circuit (OEIC) was realized for range finding applications of non-cooperative targets. The presented sensor combines the advantages of an integrated PIN photodiode, a single-stage transimpedance amplifier (TIA) and an integrating correlation stage with charge compensated switches. The large-signal bandwidth of 1.35GHz together with high responsivity R=0.36A/W at 660nm in of the PIN photodiode and the TIA with a gain-bandwidth-product GBW=52.2THzOmega ensure linearity and sensitivity of the sensor. Distance information is gained by correlating the received weak optical signal with the transmitted modulation signal. The measurement range reaches from 10cm to 15m for a minimum received optical power of 0.8nW. A standard deviation of 2.5cm (7cm) at 5m (15m) and a linearity over the measurement range of better than 12cm could be achieved. The chip was fabricated in a modified 0.6mum BiCMOS process