MERCURY-FREE UNSATURATED HIGH-PRESSURE SODIUM LAMP AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a sodium lamp capable of being easily manufactured without requiring an exhaust pipe for sealing sodium and capable of being lighted by a constant-power ballast for mercury lamp. ;SOLUTION: At least one sodium inorganic compound of a prescribed quantity selected from a group of sodium chromate, disodium tetrasulfide, sodium disufate, sodium nitrite, sodium nitrate, sodium metavanadate, sodium divanadate, sodium molydate, sodium oxalate, and sodium ozide and a getter of a prescribed quantity made of zirconium-aluminum are filled in the discharge space in a light emitting tube 2 made of a translucent member and airtightly sealed with xenon gas in this mercury-free unsaturated high-pressure sodium lamp so that the sodium evaporated and gasified in the discharge space is kept at the unsaturated state during lighting.;COPYRIGHT: (C)1997,JPO