Abstract: A passive ranging system functions in conjunction with an electro-optical imaging system to compute a range measurement based on determined changes of the image of a designated object or objects or image features representative thereof in the scene of an image sensor which is transported from one position to another with respect to the designated objects. In the present embodiment, the image sensor generates frames of image information corresponding to the one and another positions thereof while maintaining substantially a common image scene in its field of view. Image features representative of the designated image objects are extracted from at least a selected portion of the two frames for registration in accordance with a predetermined matching criteria.

Abstract: An improved target sighting device operable to converge on targets whose initial velocity has caused its image to move a significant fraction within the field of view during the period between detections utilizing less electrical circuitry and only one focal plane detector array. A detector array and associated signal processing system for incorporation within an electro-optical tracking system, the detector array comprising both fine track and coarse track detector elements wherein fine track and coarse track detector elements are further interconnected to hybrid fine track and coarse track signal processing algorithms. The resultant signals from the fine track and coarse track detections on the hybrid array will result in commands to gimbals about reflecting means or about a receiver telescope allowing the reflective means or receiver telescope means to be repositioned towards the target with greater accuracy.