DISCHARGE LAMP

A discharge lamp comprises a substantially straight glass bulb having discharge gas charged therein and an electrode provided at each longitudinal end portion of the bulb on the outer surface thereof. The discharge lamp is applied a high frequency voltage across the electrodes. The each end portion has an outer surface area per unit length of the bulb larger than that at light emitting portion of the bulb. The outer surface area may be formed uneven or in the shape of ridges and furrows at the end portions for a large surface area. the electrodes being configured to the ridges and furrows. The end portions may have a larger diameter than that of the light emitting portion of the bulb so that they have larger surface area contacting with the bulb. The each of the electrodes may have a narrow beltshaped elongate portion on outer surface of the bulb extending longitudinally of the bulb toward middle portion. thereby allowing use of a lower discharge voltage. The fluophor may be applied except inner surface opposite to the electrodes.