Discharge lamp, discharge lamp electrode, and discharge lamp electrode manufacturing method

An electrode which is arranged at an interior of a discharge lamp and which exhibits a shape of a solid of revolution,

• the electrode, comprising at an interior of a main body of the electrode:
• a heat-transmitting substance of the melting point lower than that of a material which makes up the main body;
• and
• a regulating body that is made up of a material of the melting point higher than that of the heat-transmitting substance, that includes at least one blade which extends in an axial direction of the solid of revolution and in a radial direction perpendicular to the axial direction, and that regulates convection of the heat-transmitting substance,
• wherein surface roughness Rz of at least one of a region which is on an inner wall face of the main body and with which the regulating body makes contact and a region which is on a surface of the regulating body and with which the inner wall face makes contact is not greater than 1.52 μm.

A method for manufacturing an electrode of a discharge lamp comprising the steps of:

• preparing a main body having an internal space and making up the electrode which is arranged at an interior of the discharge lamp;
• a heat-transmitting substance of the melting point lower than that of the main body;
• and a regulating body that is for regulating convection of the heat-transmitting substance and that exhibits a size permitting insertion within the internal space such that a gap intervenes therebetween;
• and
• polishing so as to cause surface roughness Rz of at least one of a region which is on an inner wall face of the main body and with which the regulating body makes contact and a region which is on a surface of the regulating body and with which the inner wall face makes contact is not greater than 1.52 μm.