Abstract: A vibratile optical boresight which can be used for conical or nutating scanning of a target by a beam of light. A lens is mounted for vibration, in at least one direction in a plane normal to the axis of the lens, between the free ends of piezo-electric cantilevered plates which are trihedral, tapering towards the free ends. The lens is carried in a canister which has arms extending to the cantilevers. The arms and the cantilevered plates can flex in a common plane to which the axis is normal.

Abstract: An optical detector of remote vibration, comprising a system for obtaining a Doppler signal by mixing reference light with laser light reflected from a vibrating object. The Doppler signal is rectified and the successively highest value of it are stored. The laser light is scanned over the object and the values of scanning waveforms at the time of storage of a maximum return signal are stored, the stored values being read out to control the direction of the laser light so as to locate the region giving maximum return.

Abstract: A detector of remote movement in which light from a laser is directed at a target and, on reflection from the target, is mixed with reference light from the laser to produce a Doppler signal denoting the movement of the target. The beam of light from the laser is directed through an optical system which brings the light to a focus and thereafter projects the light from the focus at the target. The optical system includes a lens which is mounted in a ferromagnetic carrier which can be vibrated in two orthogonal directions each normal to the axis of the light beam and the axis of the lens. Coils disposed to produce these orthogonal movements are energized in quadrature so as to produce conical scanning of the beam of light on the target.

Abstract: An optical path-length modulator which comprises a tube having at one open end a lens of which the focal length is equal to the distance between this lens and the surface of a concave mirror which is disposed at the closed end of the tube and which has a radius of curvature equal to the focal length of the lens. The tube is carried between and mounted on two spaced apart diaphragms which can flex in order that the tube may move axially. The tube constitutes an armature for an electromagnetic vibrator which includes also pole pieces surrounding the tube and a driving coil on one of the pole pieces. Energization of the driving coil causes to and fro axial movement of the tube. Collimated light entering the tube via the lens is brought to a focus at the surface of the mirror and is rereflected the way it entered.