Solid-state block-based pulsed laser illuminator for single-photon avalanche diode detection-based time-of-flight 3D range imaging

A laser diode illuminator for single-photon avalanche diode detection-based pulsed time-of-flight 3D range imaging is presented. The illuminator supports a block-based illumination scheme and consists of a 16-element custom-designed common anode quantum-well laser diode bar working in the enhanced gain switching regime and lasing at 810 nm. The laser diode elements are separately addressable and driven with gallium nitride drivers, which produce current pulses with a width of 2 ns; the current pulse amplitude was estimated from the supply voltage (90 V) as 5 to 10 A. Cylindrical optics are used to produce a total illumination field-ofview of 40 10 deg 2 (full width at half maximum) in 16 separately addressable blocks. With a laser pulsing frequency of 256 kHz and laser pulse energy of 8.5 nJ, the average optical illumination power of the transmitter is 2.2 mW.