Scanning laser based system and method for measurement of distance to a target

A distance-measurement system and method for its use. The system includes a transmitter located at one location and a receiver, at least portions of which are located at the second location. The transmitter produces a scanning beam of laser light that is narrow in its scanned direction and broad in the orthogonal direction. The beam is scanned at a substantially constant angular velocity. The receiver has at least a pair of apertures and associated photodiodes held in a predetermined configuration. The receiver measures the time interval between the times at which the apertures are illuminated by the scanning beam. Based on these time intervals, the receiver can calculate the distance from the first location to the second location. The scanned beam can also be polarized and the receiver can include polarization detection and a lateral effect cell to account for relative rotation and tilt of the transmitter and receiver.