LUMINESCENT SCREEN

摘要

Luminescent screen provided with a luminescent layer (4) which is disposed on a support (1) and comprises an alkaline earth metal aluminate activated with bivalent europium or with bivalent lead. The alkaline earth metal is strontium of which up to 25 mol.% may be replaced by calcium. The aluminate has a crystal structure the X-ray powder diagram of which corresponds to the diagram of Table I given in the description, whilst the molar ratio of total bivalent metal to aluminium in the aluminate has a value of 1:2 to 1:5. An advantageous application of such a luminescent screen is found in low-pressure mercury vapour discharge lamps.