Wire and wire like object detection system

摘要

An optical radar operating in the infrared region of the spectrum and adapted to efficiently detect elongated targets such as wires. The pulsed transmitter is preferably passively Q-switched and produces optical pulses polarized in one direction. A CW local oscillator laser is locked to a frequency slightly offset from the transmitter frequency. A Brewster angle duplexer and a quarter wave plate in the transmit/receive path of the radar permit the transmitter flux to pass to a scanner and direct the orthogonally polarized echo signals to the heterodyne receiver which includes a display or alarm circuit. The transmitter and local oscillator lasers include frequency control circuits. Either wedge or ball joint type scanners may be used to scan the radar beam over a target area of interest.