Patent ID: 7855497

Claim:
A discharge lamp for generating ultraviolet (UV) light comprising: a gastight vessel having in inner surface and filled with Xe or a Xe/Ne mixture bounded by the inner surface; an electrode attached to an outer surface of the gastight vessel; and a UV reflecting layer between the electrode and the gastight vessel, wherein the gastight vessel includes a luminescent layer comprising at least one luminescent material emitting UV-B radiation in a range of 280-320 nm, and wherein the luminescent material comprises at least one of (Y 1-x-y Gd x S y )Al 3 (BO 3 ) 4 ,(La 1-x-y Gd x S y )Al 3 (BO 3 ) 4 , (La 1-x-y Gd x S y )B 3 O 6 , (Y 1-x-y-z Gd x S y Lu z )PO 4 , (Y 1-x-y-z Gd x S y Lu z )BO 3 ,(Y 1-x-y-z Gd x S y Lu z ) 3 Al 5 O 12 , Me(Y 1-x-y Gd x S y )F 4 (Me=Li, Na, K; S═Bi, Nd, Pr; 0.0<x,z≦1.0; 0.0<y≦0.1) or a mixture thereof.