TW200509178A - Halogen gas discharge laser electrodes - Google Patents

Abstract

A method and apparatus for operating a gas discharge laser is disclosed which may comprise a laser chamber containing a laser gas, the laser gas comprising a halogen, two elongated electrode elements defining a cathode and an anode, each of the cathode and anode having an elongated discharge receiving region having a discharge receiving region width defining a width of an electric discharge between the electrode elements in the laser gas, the discharge receiving region defining two longitudinal edges, and the anode comprising: a first elongated anode portion comprising a first anode material defining a first anode material erosion rate, located entirely within the discharge receiving region of the anode, a pair of second elongated anode portions comprising a second anode material defining a second anode material erosion rate, respectively located on each side of the first anode portion and at least partially within the discharge receiving region; an elongated electrode center base portion integral with the first elongated anode portion; and wherein each of the respective pair of second elongated anode portions is mechanically bonded to the center base portion. The electrode element may comprise a cathode. The first and second materials may be different materials such as different brass alloys with different erosion rates in the halogen gas. The first elongated cathode portion may comprising a first cathode material, located entirely within the discharge receiving region comprising a first portion of an ellipse intersecting elongated side walls, with a bottom wall opposite the portion of the ellipse; and a pair of second elongated cathode side portions comprising a second cathode material with the intersection of each respective second cathode portion and the portion of the ellipse forming the discharge receiving region of the first cathode portion, forming respective ellipsoidal extensions of the first portion. The members may be mechanically bonded to the center base portion. Some may be diffusion bonded to the center base portion and/or each other. The electrode assembly may have a hooded discharge receiving region extension at respective ends of the electrode and the electrode portion may be formed with or bonded to the center base portion and may have slanted side walls.