Discharge lamp

Abstract

This discharge lamp is provided with a discharge tube, and a pair of electrodes disposed in the discharge tube, and at least one of the electrodes comprises an enclosed space into which a heat transfer element that melts and convects while the lamp is lit is sealed, and a hollow rectification body disposed along an electrode axis within the enclosed space and having an enclosed space bottom surface-side opening and an enclosed space top surface-side opening. A flow path for the heat transfer element is formed between the enclosed space bottom surface-side opening and the enclosed space top surface-side opening, and the rectification body is disposed such that the electrode axis passes through the flow path.

Description

technical field [0001] The present invention relates to a discharge lamp used in an exposure device, and more particularly to an electrode in which a heat transfer body is sealed inside the electrode. Background technique [0002] In a discharge lamp, an electrode is known in which a metal having a cooling function is enclosed in a sealed space formed inside the electrode along with the increase in output (see Patent Document 1). Among them, a heat transfer body made of a metal with high thermal conductivity and low melting point such as silver is sealed inside the anode. When the electrode temperature rises due to lighting of the lamp, the heat transfer body melts and is liquefied. As a result, heat convection occurs in the closed space, and the heat at the tip of the electrode is transported toward the electrode support rod on the opposite side. [0003] If the heat transfer body conducts convection when the lamp is turned on, a strong temperature difference will occur i...

AI Technical Summary

Problems solved by technology

[0003] If the heat transfer body conducts convection when the lamp is lit, a strong temperature difference will be generated in the closed space inside the electrode, which may cause high temperature creep deformation

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