Shared aperture dichroic active tracker with background subtraction

Abstract

An imaging self-referencing target tracker ( ) for a laser weapon ( ). The weapon generates a first beam of radiation ( ) that engages a target ( ) to form a beam hit spot ( ) thereon. In a first embodiment, a target illuminator ( ) (variant ) illuminates the target with a second beam of radiation ( ). An optics subsystem ( ) receives and separately images the first and second beams ( ) of radiation. In a second embodiment, a blocking filter ( ) is implemented rather than an illumination laser to pass only radiation at the target wavelength, thereby ensuring that the first and second beams of radiation are separately imaged. A controller ( ) is programmed to steer the first and second beams of radiation to the desired target aim point ( ) in response to information from the imaged first and second beams of radiation. The tracker of the present invention tracks the laser hit spot relative to the actual target image in a closed loop manner, thereby increasing the probability of accurate target engagement and resulting in a target kill.