Patent ID: 6373189
Filing Date: 2002-04-16
Classification: G03F,H01J

Abstract:
Mercury lamp of the short arc type comprising a qua arc tube in which a cathode and an anode are disposed opposite one another and which is filled with mercury and a rare gas; wherein the rare gas comprises at least one of argon (Ar) and krypton (Kr) with a pressure from 1.0 to 8.0 atm at room temperature; also wherein the relationship 0.3&lE;X/L&lE;0.6 is satisfied, where L is a length of the arc tube in an axial direction in mm, and X is a length of the cathode which projects in an axial direction into an emission space in mm, the direction between the anode and the cathode being defined as the axial direction, and wherein the relationships 0.85D&gE;(X+5) and 0.85D&gE;Lâˆ’(X+5) are satisfied, where D is the maximum outside diameter of the arc tube in a radial direction in mm, the radial direction being defined as the direction of a cross section which is perpendicular to the axial direction of the arc tube.