Device for visualizing a cathode-ray tube coloured image equipped with a holographic element, and method of producing said element

摘要

1. A cathode ray visualisation device comprising a colour cathode ray tube, the screen of which is constituted of luminophore elements behind a mask, and comprising a transparent plate bearing a hologram and disposed outside the tube and close to the screen in order to limit the observation field of the image visualized by the screen, characterized in that the hologram of said plate (5) constitutes a holographic optical element (5A) acting as a set of converging lenses, the distribution of lenses being identical to that of the luminophore elements (9), each lens (8) being associated to a luminophore element situated in its focal plane, and the surface of each lens being larger than that of the luminophore element such that the effective luminosity of the screen (1) is increased for the observator.