Patent ID: 6965193

Claim:
An arc discharge lamp having an improved color rendering index for a given color coordinated temperature, the lamp comprising a lamp envelope enclosing a discharge space and having an inner surface; an ionizable medium within said lamp envelope comprising mercury and an inert gas; first and second electrodes; and a phosphor layer comprising a phosphor blend on said inner surface, said blend including: a green phosphor having a peak emission at about 525 to about 570 nm, a blue-green phosphor having a peak emission from about 475-525 nm, a blue phosphor having a peak emission from 430 to 460 nm and a red phosphor selected from the group consisting of SrY 2 O 4 :Eu 3+ , (Y,Gd)Al 3 B 4 O 12 :Eu 3+ , and [(Y 1-x-y-m La y )Gd x ]BO 3 :Eu m wherein y<0.50 and m=0.001-0.3.