Patent ID: 7164226

Claim:
A high-pressure discharge lamp, comprising: a light emission tube having a light emission portion, a pair of electrodes disposed so as to be opposed to each other in the light emission portion, and a pair of side tube portions elongating from ends of the light emission portion along an axis line connecting the electrodes, a support structure for supporting the light emission tube so as to restrict a displacement of the light emission tube at least in a direction perpendicular to the axis line, and a pair of thermal-stress generation members, base end sides of which are supported by the support structure, and tip end sides of which are connected to the side tube portions of the light emission tube, the thermal-stress generation members generating thermal stresses by a temperature change at a time of switching the high pressure lamp from an on status to an off status, and the thermal stresses acting as forces directed downward in a vertical direction and outward with respect to the light emission tube on the side tube portions of the light emission tube arranged in a posture where the axis line extends in a substantially horizontal direction.