Abstract: A coincidence and stereoscopic binocular rangefinder is disclosed for measuring distance to sighted targets. The rangefinder preferably has three optical windows for receiving radiation from a sighted target allowing the user to use both his ability to align separated images in one of the eyepieces of the rangefinder, and his ability to stereoscopically sense and compare apparent target depths using both eyepieces of the rangefinder. The rangefinder also includes a novel feature whereby the binocular portion may be easily and conveniently detached from the rangefinder and used separately, and then easily reattached when distance measurement is again desired.

Abstract: A stereoscopic rangefinder is disclosed for determining the distance of a target object by measuring the angle of parallax of light scattered by the target. The rangefinder includes two arrays of photosensitive elements upon each of which a distinct target image is projected. A measurement of the pixel displacement between the two target images is used in measuring the angle of parallax. A novel computational scheme is included in the rangefinder wherein it is self-correcting with regard to mechanical shock and thermal influences such that a user need only "point and shoot." Further, the rangefinder is insensitive to target image blur and is embodied as a hand held rangefinding binocular having no moving parts.

Abstract: A device to precisely determine the angle of parallax formed by a target object of interest and first and second entrances (30, 30') for the purpose of rangefinding for example. The device having photodetectors (46) for sensing the separation of first and second channel target scene images (68, 68') and for sensing the separation of first and second channel reference marker images (66, 66') and having electronic circuitry (76) and processor (78), wherein by comparison of these separations, may calculate an accurate angle of parallax of the target object of interest and provide the resultant information to the user via a display (80). The device includes a spatial referencing system (14) and therein, the device may automatically account for small misalignments of optical elements which may occur during normal use and in certain embodiments of the device may allow the user to isolate the target object of interest from other objects which may appear in the field of view.