Abstract: A UV-emitting, Ce,Pr-coactivated calcium pyrophosphate phosphor is provided wherein the Pr activator increases the phosphor's sensitivity to excitation by 185 nm radiation. The improved sensitivity to the 185 nm radiation allows the phosphor to make better use of the approximate 10% of the UV radiation that is emitted at 185 nm by a low pressure mercury discharge.

Abstract: A UV-emitting phosphor and lamp containing same are described. The phosphor is a praseodymium-activated pyrophosphate-based phosphor which may be represented by the general formula (Ca2-x,Srx)P2O7:Pr where 0?x?2. The phosphor is excitable by vacuum ultraviolet (VUV) radiation and in particular it may be excited by Xe-excimer discharges and thereby provide a Hg-free UV-emitting lamp. The phosphor exhibits a broad emission in the UVC region in the wavelength range from about 220 nm to about 280 nm with the peak emission occurring in the wavelength range from about 230 nm to about 240 nm. The emission characteristics of the phosphor may be varied depending on the ratio of Sr/Ca.