Luminescent quartz glass, method of preparing such a glass and luminescent screen provided with such a glass

Abstract

Luminescent quartz glass comprising as a glass matrix oxide mainly SiO.sub.2 and furthermore per mole of SiO.sub.2 from 0 to 0.15 mol of at least one of the oxides Al.sub.2 O.sub.3, B.sub.2 O.sub.3, P.sub.2 O.sub.5, ZrO.sub.2, Sc.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, Gd.sub.2 O.sub.3, Lu.sub.2 O.sub.3, the alkali metal oxides and the alkaline earth metal oxides. The glass comprises as an activator oxide at least one of the oxides Tb.sub.2 O.sub.3 and Ce.sub.2 O.sub.3 in a quantity of 0.75 to 15 mol % calculated with respect to the glass matrix oxides. In one embodiment the glass comprises Tb.sub.2 O.sub.3 and also not more than 0.2 mol % of Eu.sub.2 O.sub.3 as an activator oxide. The glasses are preferably obtained by a sol-gel technique and are useful, for example, in luminescent screen of low-pressure mercury vapor discharge lamps.

Dependencies are inferred from the claim text.