Abstract: The invention relates to headsets comprising at least a supporting shell and a moving visor that can be displaced between two extreme positions. The headset includes a system for securing the visor in any position between the two extreme positions by friction between the visor and the supporting shell, the friction being produced by at least one microfibre felt element. The invention applies to the field of headsets in general for users of motorized craft such as in aeronautics and automobiles for example.

Abstract: Optical devices using thin optical films to adapt the characteristics of a light radiation. An optical device includes an optical structure and thin optical films interposed in the path of a light radiation that gets propagated towards the optical structure. The optical films are placed in an enclosed space having dimensions that are greater than the dimensions of the optical films so that the latter are maintained by a float mounting that allows each of them freedom of movement. The device prevents mechanical strains created by differential thermal expansion. Such optical devices may find particular application to liquid crystal display screens.

Abstract: The present invention provides an improved design for a mechanical pump. The pump is a dual chamber design typically including a pair of expandable bellows driven in a reciprocating fashion by a supply of pressurized air. The use of expandable bellows reduces wear on the pump thereby lengthening the required maintenance intervals in comparison with dual chamber diaphragm pumps previously known. Additionally, the pump is easily disassembled for inspection, cleaning or maintenance. Furthermore, the high strength of the pump's design makes it possible to manufacture the pump entirely of corrosion resistant materials.

Abstract: The present invention provides an improved design for a mechanical pump. The pump is a dual chamber design typically including a pair of expandable bellows driven in a reciprocating fashion by a supply of pressurized air. The use of expandable bellows reduces wear on the pump thereby lengthening the required maintenance intervals in comparison with dual chamber diaphragm pumps previously known. Additionally, the pump is easily disassembled for inspection, cleaning or maintenance. Furthermore, the high strength of the pump's design makes it possible to manufacture the pump entirely of corrosion resistant materials.