GB778905A - Electroluminescent lamps - Google Patents

Abstract

778,905. Electroluminescence. SYLVANIA ELECTRIC PRODUCTS, Inc. Aug. 20, 1953 [Aug. 20, 1952], No. 23029/53. Class 39(1). A lamp comprises a layer of compressed electroluminescent material disposed between and in electrical contact with two electrodes. The layer 3, e.g. zinc sulphide with zinc oxide or zinc selenide activated by manganese, copper or lead and containing zinc chloride, or triactivated calcium phosphate or manganese activated zinc or cadmium silicate is spread over a transparent conductive coating 2 of silicon, tin or titanium chloride inside a masked portion and pressure applied which will not break the glass support 1 e.g. up to 9000 pounds/sq. in. A metal backing 3 is applied as a foil or paint or by evaporation in vacuum, and covered by a thin mica sheet before moulding a plastic covering 6 thereover. A smaller quantity of metal particles, e.g. 5-10 per cent, may be mixed with the electroluminescent material or a thin metal film evaporated on an electroluminescent layer followed by milling to produce crystals partially coated with metal, small enough to avoid short circuiting. Specifications 567,184 [Group XL] and 778,907 are referred to.