Patent ID: 7119488

Claim:
An arc discharge lamp having an improved luminosity for a given color rendering index and 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 comprising: a green phosphor having an emission peak at 515–550 nm, an orange phosphor having an emission peak from 550–600 nm, a red phosphor having an emission peak at 600–670 nm, and a blue phosphor comprising at least one of (Sr,Ba)MgAl 10 O 17 :Eu 2+ , (Sr,Ca,Ba) 5 (PO 4 ) 4 Cl:Eu 2+ , and (Ba,Ca) 5 (PO 4 ) 3 Cl:Eu 2+ .