US Patent 10007001 Active short-wave infrared four-dimensional camera

A lidar system operates as an active short-wave infrared (SWIR) camera system to determine a four-dimensional image at each point in a two-dimensional field of regard. The camera system includes a short-wave infrared spectrum scanner that transmits a pulse of light at a particular position or coordinate in a two-dimensional field of regard and a receiver that detects return pulses scattered from a target in the field of regard coincident with the particular position. The receiver includes a detector that detects the returned pulse, a range determination unit that determines, based on the timing of the returned pulse, a distance to the target at the particular position, and an intensity measurement unit that determines the magnitude, amplitude, or intensity of the returned pulse, which information provides an indication of the relative, or in some cases, absolute reflectivity of the target at the particular point in the field of regard.