Mercury discharge lamp of the short arc type
AssigneeUshiodenki Kabushiki Kaisha
InventorsYukio Yasuda, Yoshinoir Aiura
Life of this patent
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Abstract
A short arc mercury discharge lamp including an arc tube filled with at least mercury and a rare gas, a cathode and an anode positioned opposite to each other within the arc tube, the cathode having an tapered area which tapers in a direction towards the anode and a projection which protrudes from the tapered area in a direction towards the anode. The amount of mercury to be added in the arc tube is in a range of 0.2≦n≦52, where n is the weight (mg/cm3) of the mercury per unit of volume, and a pressure of the rare gas to be added in the arc tube is in a range of 0.1≦p≦800, where p is the pressure (kPa) of the rare gas at an ambient temperature of 25° C.
Claims14
A short arc mercury discharge lamp comprising:
- an arc tube filled with at least mercury and a rare gas;
- a cathode and an anode positioned opposite to each other within the arc tube, the cathode having a tapered area and a projection, the tapered area tapering in a direction towards the anode and the projection axially projecting from the tapered area in a direction towards the anode,
- wherein the amount of mercury added in the arc tube is in a range of 0.2≦n≦52, where n is the weight (mg/cm3) of the mercury per unit of volume and a pressure of the rare gas added in the arc tube is in a range of 0.1≦p≦800, where p is the pressure (kPa) of the rare gas at an ambient temperature of 25° C.
Dependencies are inferred from the claim text.