Abstract: In a high-pressure discharge lamp that includes a bulb formed from a light emitting part having a discharge space therein and a pair of sealing parts connected to the light emitting part, and an electrode pair disposed within the discharge space, a section of a proximity conductor is wound substantially spirally around one of the sealing parts within a predetermined range from the light emitting part, while the remaining section of the proximity conductor crosses over the light emitting part and is electrically connected to the electrode nearer the other sealing part. By initiating a discharge after applying a high-frequency voltage of 1 kHz to 1 MHz to a high-pressure mercury lamp having this structure, the breakdown voltage can be suppressed to at least 8 kV.

Abstract: A method for manufacturing a high pressure mercury lamp having a high pressure resistance strength includes an electric field application step of applying an electric field to at least a light emitting part while keeping the high pressure mercury lamp at a high temperature. As a result of the electric field application step, impurities such as hydrogen and an alkali metal existing in a discharge space and in glass used for forming the light emitting part (1) and sealing parts (2) can be reduced, with it being possible to suppress blackening and devitrification during lighting.

Abstract: A lighting method for a high pressure discharge lamp in which a high-pressure pulse is applied to cause a dielectric breakdown, and then in step S1, it is judged whether the lamp voltage is higher than 25 volts as the current switching voltage. If it is judged negatively in step S1, the control circuit (304) performs a constant current control with the current limiting level set to 6 amperes (step S2). If it is judged that the lamp voltage is higher than 25 in step S1, the control circuit (304) performs a constant current control with the current limiting level set to 4 amperes (step S3). When the lamp voltage rises and reaches 50 volts, the control circuit (304) performs a constant power control so that the lamp power remains to be 200 W.

Abstract: A lighting method for a high pressure discharge lamp in which a high-pressure pulse is applied to cause a dielectric breakdown, and then in step S1, it is judged whether the lamp voltage is higher than 25 volts as the current switching voltage. If it is judged negatively in step S1, the control circuit 304 performs a constant current control with the current limiting level set to 6 amperes (step S2). If it is judged that the lamp voltage is higher than 25 in step S1, the control circuit 304 performs a constant current control with the current limiting level set to 4 amperes (step S3). When the lamp voltage rises and reaches 50 volts, the control circuit 304 performs a constant power control so that the lamp power remains to be 200W.