DISCHARGE LAMP, ELECTRODE FOR DISCHARGE LAMP, MANUFACTURING METHOD OF ELECTRODE FOR DISCHARGE LAMP, AND LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To realize a long lifetime and small diameter of a hot cathode type discharge lamp. SOLUTION: The discharge lamp 11 has an electrode 3 at both ends. The electrode 3 has a heater 4 in which a first lead 4b and a second lead 4c extend from back end side of a coil part 4a and an electron emitting substance 3a is coated. In the electrode 3, the first reed 4b is connected to a first leading-in wire 6a and the second reed 4c is connected to a second leading-in wire 6b, and the coil part 4a is arranged in vertical direction along the tube axis of a glass tube 2. Then, the electrode 3 is provided with a sleeve 7 covering the surroundings of a coil part 4a by opening the faces opposed to the top end and the back end of the coil part 4a. By having the opening end face 7a of the sleeve 7 protruded than the top end of the coil part 4a, the coil part 4a is protected. COPYRIGHT: (C)2005,JPO&NCIPI