Abstract: A compact optical device used to superimpose an intensified infrared image onto a visible image to allow night vision. It can especially be used to make goggles to be worn under the visor of an aircraft or helicopter pilot's helmet. The device includes a combiner located in front of the pilot's eye for directly transmitting visible light to the pilot and an objective for receiving infrared light which is placed above the combiner. An optical system guides the light received by the objective towards the combiner to be forwarded to the pilot's eye. The light is guided in a single plane substantially perpendicular to the plane containing the light received by the objective. The optical system includes a light intensifier, a transport objective, an even number of mirrors to fold the optical circuit and an eye piece.

Abstract: A head-mounted visor with variable transmission has at least two zones with different values of absorption of light. Should the visor be mounted on a pilot's helmet, an upper zone designed for looking at the exterior of the aircraft absorbs more light than a lower zone designed for looking at the dashboard instruments. The application is directed to helmet equipment for tasks comprising swift passages from a very bright space to a darkened space.