Abstract: A device for radiation detection over a broad field, especially for laser radiation detection. The device comprises a photodetector associated with an optical receiver formed by two diaphragms which delimit the field, and an optical diffusing element. In a preferred embodiment, a diffusing paint is deposited on a flat surface of a mechanical part, and a mirror for reflecting the diffused radiation makes it possible to mount at the rear end of the device either the photodetector or an optical fiber terminal to which the photodetector is remotely coupled.

Abstract: An optical device comprising at least an optical element having a cut away area and which supports an inner mechanical structure accommodated in the cut away area, the whole being supported by an outer mechanical structure without obstruction in the optical path between the structures. The contact areas of the optical element with the structures comprise mechanical gripping and position means including deformable members for holding an unvaried centered position to the optical element for severe temperature and mechanical operating conditions.

Abstract: A radiant energy detection system for discriminating between radiation from a target and ambient radiation wherein optical receiver means is arranged to produce two images of the observed field which are staggered along the direction of displacement of modulating grids by an amount substantially equal to the diameter of the target image, and which includes filtering means and attenuating means to balance the radiation levels in the case of ambient background radiation.