Abstract: In a weapon boresighting system for aircraft and other vehicles a pair of spaced apart, collimated laser beams oriented to a fixed reference line on the vehicle are transmitted to a receiver positioned at the weapon or other module to be boresighted, the receiver having a first section including a position sensitive cell for measuring pitch and yaw relative to a pitch and yaw reference surface and a second section including a position sensitive cell for measuring roll relative to a roll reference surface.

Abstract: In a weapon boresighting system for aircraft and vehicles, an optical square is oriented to a fixed reference line on the vehicle and provides the directionality of a pair of orthogonally positioned of laser illuminated retroreflective catadioptric collimators attached to said optical square whose outputs are directed via one or more deviators or periscopes to a pair of retroreflective catadioptric receivers orthogonally attached to a second optical square positioned at the weapon to be boresighted, each said receiver imaging the laser on a position sensitive sensor, the outputs of the latter indicating the pitch roll and yaw condition at the weapon.

Abstract: A surveying instrument and procedure are provided for the precise determination of elevation differences in the course of a surveying traverse. The instrument comprises an optical wedge 13 situated on the horizontal longitudinal line of sight axis 27 of the primary optical system between the objective lens 11 and a target under observation. The wedge is arranged for rotation about this axis and with such rotation angularly displaces the diverted line of sight 28 from the horizontal to the plane of the target. The degree of rotation required of the wedge to acquire the target 33 is measured by electro-optical angle encoder means 10, and the distance to the target by EDM means 24, 26. The difference in elevation is calculated trigonometrically by computer means utilizing as data the wedge diversion angle, the sine function of its rotation, the computed angular displacement of the line of sight, and the distance to the target.

Abstract: The invention provides a highly corrected catadioptric telephoto lens comprising in succession, from the long conjugate end, an aspherized negative meniscus corrector plate, a Mangin type primary mirror which directs light to a secondary mirror comprising the central portion of the second surface of the corrector lens, a first positive meniscus corrector lens and a second biconcave corrector lens. The relative aperture is f/8 and the overall length of the system from first vertex to image plane is less than 0.4 focal length.