Thin film energy-controlled variable color cathodoluminescent screens

A new technique for obtaining energy-variable multicolor cathodoluminescent display screens is presented. This technique employs radio frequency ion plasma sputtering of one thin-film phosphor material over a dissimilar phosphor substrate. The technique employed differs from the old ''Penetron'' screen in that the substrate and the secondary phosphor layer are single-crystal materials. This results in higher resolution and allows the use of lower energy beam excitation. The experiments presented use Y2O3:Eu (red) deposited on a Y3Al5O12-Tb,Ce (green) substrate with excitation in the low killovolt range. The method demonstrated, however, is extendable to a full red-green-blue triplet composed of a wide variety of materials. The screens are particularly applicable to small, low-power formats, such as avionics and instrumentation displays.