Laser Diode Array Driver With Inductor Current Recirculation

The illumination array is divided into multiple rows of laser diodes that can be independently controlled. The controller selectively activates only the rows needed for each scanning line, rather than driving the entire array simultaneously. This segmentation allows high-resolution imaging with fine granularity while maintaining driving efficiency by activating only the necessary portion of the array for each measurement cycle.

The inductor is pre-charged to the required current level before each laser pulse is emitted. The controller manages the timing so that the inductor charging occurs during the interval between pulses, and the charged inductor current is then rapidly discharged through the selected laser diode row. This preliminary charging action ensures that when the pulse is needed, the current is already available, eliminating charge time delays during the actual measurement cycle.

The system uses periodic pulsed operation where current is applied to the laser diodes in discrete time intervals rather than continuously. The inductor stores energy during the off-period and releases it in controlled pulses during the on-period. This periodic action allows the system to accommodate large numbers of diodes while maintaining high efficiency, as energy is only consumed during the brief pulse intervals rather than continuously across the entire array.