Lamp, phosphor and method

Claim 1

THE COMBINATION WHICH COMPRISES: A POWER-OPERABLE ARC TUBE HIGH-PRESSURE DISCHARGE SOURCE HAVING THE CHARACTERISTIC OF EMITTING ULTRAVIOLET RADIATIONS AND VISISBLE RADIATIONS; A LIGHT-TRANSMITTING ENVELOPE SURROUNDING SAID ARC-TUBE SOURCE; A RADIATION-TRANSMITTING MEMBER POSITIONED INTERMEDIATE SAID ARC-TUBE SOURCE AND SAID ENVELOPE; A PHOSPHATE PHOSPHOR CARRIER ON SAID RADIATIONTRANSMITTING MEMBER; THE POSITION OF SAID RADIATION-TRANSMITTING MEMBER WITH RESPECT TO SAID ARC-TUBE SOURCE BEING SO SELECTED THAT WHEN SAID ARC-TUBE SOURCE IS OPERATED, SAID PHOSPHOR EFFICIENTLY CONVERTS ULTRAVIOLET RADICATIONS GENERATED BY SAID ARC-TUBE SOURCE INTO VISIBLE RADIATIONS, AND SAID PHOSPHOR HAVING AS ESSENTIAL METALLIC ELEMENTS; TERBIUM; COPPER AT LEAST A PORTION OF WHICH IS IN THE CUPROUS STATE; AND AT LEAST ONE OF THE GROUP CONSISTING OF STRONTIUM, CALCIUM AND BARIUM; A RATIO OF ATOMS OF COPPER TO ATOMS OF PHOSPHORUS IN SAID PHOSPHOR OF FROM 0.001:2 TO 0.06:2, A RATIO OF THE SUM OF ATOMS OF TERBIUM TIMES 1.5 PLUS ALL ATOMS OF THE ELEMENTS OF SAID GROUP PLUS ATOMS OF COPPER TIMES 0.5 TO ATOMS OF PHOSPHORUS IN SAID PHOSPHOR OF FROM 2.2:2 TO 3.08:2; AND A RATIO OF ATOMS OF TERBIUM TO ALL ATOMS OF THE ELEMENTS OF SAID GROUP IN SAID PHOSPHOR OF FROM 1:4 TO 1:150.