Laser Beamrider Detection System

Advances in laser based weapons constitute a real threat to military aircraft. Detection of incident laser beam illumination early enough to allow an active response is vital. A laser beamrider detection system must have a high probability of detection with a low false alarm rate. This proposal addresses the difficult problem of detecting hostile laser illumination against bright daylight backgrounds over a wide field of view without knowledge of the laser's wavelength or pulse repetition rate. A high resolution imaging sensor is proposed capable of running at 1,000,000 frames/sec, thus combining high spatial and temporal resolution to reduce the ambient background signal without attenuating the sub-microsecond pulsed laser signal. With this sensor, background noise can be reduced to a level where knowledge of the laser's wavelength is not needed and narrow band optical filtering not necessary in order to detect incident low-intensity laser beams in the daytime, over a wide field of view. The proposed detector employs "smart pixels¿ to avoid the impossible burden of reading out the image a million times a second, and thus provides a high duty factor for detecting pulses from threat laser systems.