Abstract: A matrix screen for displaying multiplexed colour images, wherein the screen comprises several selection modules each connected to at least one colour source, in that each selection module comprises different selection terminals, a single selection terminal per selection module being activated during the same screen operating phase or sub-frame, and in that the optoelectronic devices of the screen belonging to the same colour family.

Abstract: A lens unit for observing an object, comprises an optical system comprising one or more successive lenses, and an optical device, comprising: at least one first optical element of the lens type, defining a front surface and a rear surface, the first optical element being produced from an optically transparent material and having a refractive index “n1”, a second optical element, defining a front surface and a rear surface, and being optically coupled by its front surface to the rear surface of the first optical element, the second optical element being produced from a material with a refractive index n2 and provided with at least one portion produced from a material optically absorbing visible light. The optical device being substituted for the lens of the optical system or at least for the end lens among the successive lenses in the optical system.

Abstract: A lens unit for observing an object, comprises an optical system comprising one or more successive lenses, and an optical device, comprising: at least one first optical element of the lens type, defining a front surface and a rear surface, the first optical element being produced from an optically transparent material and having a refractive index “n1”, a second optical element, defining a front surface and a rear surface, and being optically coupled by its front surface to the rear surface of the first optical element, the second optical element being produced from a material with a refractive index n2 and provided with at least one portion produced from a material optically absorbing visible light. The optical device being substituted for the lens of the optical system or at least for the end lens among the successive lenses in the optical system.