New phosphors for lamps

Abstract

The method of preparation and the applications of four new phosphors are discussed in relation to their use in different types of lamps. Europium-activated yttrium phosphate vanadate made with the addition of boric acid is a red-emitting phosphor used in fluorescent high pressure mercury vapour lamps. Strontium pyrophosphate activated by divalent europium has been used in fluorescent lamps for photocopying and has enabled higher reproduction rates to be achieved. Barium strontium disilicate activated by divalent europium may find application in fluorescent lamps with improved colour rendering properties, and manganese-activitated magnesium aluminium gallate in fluorescent lamps used for xerographic reproduction.