Abstract: The discharge lamp according to the present invention is composed of a slender translucent airtight vessel 1a, an inner electrode 1c fixed inside one end of 1a, a discharge lamp 1 provided with a discharge medium composed mainly of rare gas, and an outer electrode 2 composed of a conductive wire arranged on the outer surface of translucent airtight vessel 1a. The outer electrode 2 is placed within a half circumference of the translucent airtight vessel in a first area 2a of the translucent airtight vessel 1a, which extends in a range between a top end of the inner electrode 1c and a position having a predetermined length in the forward direction of the translucent airtight vessel 1a. The outer electrode 2 is placed within an entire circumference of the translucent airtight vessel 1a in a second area 2b of the translucent airtight vessel 1a, which extends in the rest of the length of the translucent airtight vessel 1a.

Abstract: A transparent airtight vessel 1a, a discharge medium enclosed in a transparent airtight vessel 1a and composed mainly of rare gas, a fluorescent lamp 1 provided with at least a pair of electrodes 1b, 1e which generate discharge inside the transparent airtight vessel 1a, a reflection means 2 arranged in the vicinity of the fluorescent lamp 1, and a transparent resin 3 which exists between the fluorescent lamp 1 and the reflection means 2 and contacting with both of them. The transparent resin 3 conducts heat generated by the fluorescent lamp 1 to the reflection means 2 and promotes the heat radiation. The heat radiation of the rare gas discharge lamp is then promoted and the decrease of the light emitting efficiency is suppressed.