Abstract: A panoramic display system for use in a vehicle equipped with a plurality of episcopes (22) includes an information gathering sensor and a plurality of displays (24) for the gathered information. Each display (24) is associated with a respective episcope (22) and is operable to display the information gathered from a field of view corresponding to the respective episcope.

Abstract: A dual-band optical system 10 preferably for use in the thermal infrared waveband provides initial detection of a target in a first waveband (8-12 .mu.m) having a wide field of view and discriminated target recognition in the second waveband (3-5 .mu.m) at higher magnification and narrow field of view without any field-of-view change mechanism. The system 10 comprises a detector array 11 which is responsive in both wavebands and an optical arrangement 16 with a common objective component 15 for both wavabands. One waveband is transmitted through dichroic beamsplitters 17,18 to the array 11 whereas the other waveband is reflected by the beamsplitters 17,18 and transmitted through a field lens 28 before reaching the array 11. Both wavebands are incident upon a spectrally selective aperture stop 20 providing a large aperture for the low magnification field and a small aperture for the high magnification field.

Abstract: An optical system 10 comprises a light source 12 which may be either a point source or collimated and an arrangement 11,22 for directing a beam of light from the source 12 towards a boresighting arrangement 16 associated with an imaging lens 14 for imaging objects in object space 13 onto a detection surface 15. The boresighting arrangement 16 provides a marker on the surface 15 denoting the pointing direction 18 of the system 10 and is arranged so that the marker is of box-like pattern (17A, B 19A, B) closely centred on the pointing direction 18 so as to avoid obscuration of that part of the object image which is coincident with the pointing direction 18.

Abstract: An object-space scanning system for radiation wherein the scanning device comprises sets of planar reflecting surfaces arranged in pairs, one from each set, such that the two surfaces in a pair are disposed substantially at right angles to each other and the line of intersection of the surfaces is at right angles to the axis of rotation of the scanning device which is so arranged that incident radiation is sequentially reflected from the two surfaces of a pair before entering a focussing arrangement which focusses the radiation into a detector, the secondary scan direction being achieved by the fact that the angle included between the planar reflective surfaces of respective pairs differs by a very small angle successively around said axis.

Abstract: A radiation scanning system having a radiation detector which receives radiation from a focussing system after reflection from first and second scanners which are rotatable about parallel axes, and in which the first scanner is annular having its reflective surfaces on its outer periphery, the rotational axis of the second scanner being displaced by a distance which is less than the radius of the second scanner from the plane containing the rotational axis of the first scanner and the axis of the radiation focussing system.

Abstract: In a radiation scanning system, scanning is achieved by rotation of two drums about parallel axes. The first drum is rotated at an angular speed s.sub.1 and has n.sub.1 reflective surfaces at a distance r.sub.1 from a first axis of rotation. The second drum is rotated at an angular speed s.sub.2 and has n.sub.2 reflective surfaces at a distance r.sub.2 from a second axis of rotation. The axes are separated by a distance d. A detector is located a distance a from the first axis. The following conditions hold:2 a(n.sub.1 /n.sub.2 -1).sup.2 + 2 d(n.sub.1 /n.sub.2).sup.2 +r.sub.2 (n.sub.1 /n.sub.2).sup.2 =r.sub.1 (2n.sub.1 /n.sub.2 -1).sup.2 , (i)n.sub.1 s.sub.1 =n.sub.2 s.sub.2.

Abstract: Apparatus for use in a radiation scanning system comprising a radiation detector and an optical system arranged to scan radiation from a field of view across the radiation detector. The optical system includes two sets of planar reflective surfaces, one set being movable relative to the other, and a rotary assembly carrying one of the sets and rotatable about an axis of rotation. The detector is arranged relative to the optical system such that the radiation enters the detector after sequential reflection from reflective surfaces of the two sets, and the surfaces which effect the sequential reflection being separated by a predetermined amount and being located with respect to the axis of rotation such that the angle of incidence of radiation at the detector is independent of the position of the radiation in the field of view.

Abstract: A radiation scanning system which includes a radiation detector located at the focus of an objective lens element and a radiation scanning element arranged to scan radiation emanating from a field of view across the detector. The radiation forms a primary pupil, and one of said elements is located at a conjugate pupil formed by an optical assembly which comprises first and second concave part-spherical reflectors respectively having their centers of curvature substantially optically coincident with the locations of the primary pupil and the conjugate pupil, and a convex reflector substantially coincident with the locus of the focii formed by parallel beams of radiation emanating from the primary pupil and incident upon the first concave reflector.

Abstract: A radiation scanning system comprising a focusing lens which forms an image of radiation received from a field of view and a curved reflector is arranged to reflect radiation onto a plane mirror which is mounted for oscillatory motion about a fixed axis to thereby scan the radiation image. A relay lens is interposed between the plane mirror and a radiation detector and in the plane normal to the axis about which the plane mirror oscillates the radius of curvature of the curved reflector approximates to twice the radius of curvature of the scanned image and in this way the scanned image is presented to the detector at a substantially constant angle.