A pre-ionizing system in which the pre-ionizer elements are integral with the cathode insulating plate is provided. The cathode insulating plate includes a recessed region machined into the front surface into which the cathode fits, lying substantially flush with the insulator front surface. The back surface of the insulating plate contains a pair of slots running parallel to the long axis of the cathode. The pre-ionizing rods are located within these slots, the slots having sufficient depth to locate the rods approximately adjacent to the cathode. By maintaining the rods at ground, a capacitor is formed in which the insulating plate material between the rod and the cathode acts as the dielectric material of the capacitor. When a voltage pulse is applied, a capacitive corona discharge is formed which pre-ionizes the gases in the region near the cathode.
An apparatus designed to prevent, by adjusting a flow of laser gas, discharge products from stagnating and being released again into a main discharge space, maintain the purity of the laser gas in the main discharge space, and stabilize the main discharge so as to minimize laser output fluctuation, in which conductors are interposed in the gaps between a main discharge electrode and a pair of corona preliminary ionization electrodes, from the upper surface of a support plate to the discharge starting points.
The present invention is a device for avoiding sliding discharges in pre-ionization in a gas laser with corona discharge. The invention uses a pair of main electrodes provided in a closed gas discharge volume, and at least one pair of corona electrodes which are arranged in the immediate vicinity of the pair of main electrodes. The individual electrodes, which include a tube-like sheathing of dielectric material, are designed to be open on both ends and contain an electrically conducting rod, or core, introduced into the interior and projecting beyond the sheathing. The invention is distinguished by the provision that the material selection, the shaping of various elements associated with the gas discharge volume, or a combination of material selection and shaping is made in such a way that a specific capacitance per unit area is provided in the surface region on both ends of the sheathing is lower than the capacitance in the central region of the sheathing between its both ends. Some of the elements that may be altered as to material selection and/or shaping considerations include the sheathing surrounding the electrically conducting core, the dielectric insert body inserted between said sheathing and said electrically conducting core, and the electrically conducting core.
A corona-discharge type, preionizer assembly for a gas discharge laser is disclosed. The assembly may include an electrode and a hollow, dielectric tube that defines a tube bore. In one aspect, the electrode may include a first elongated 0o conductive member having a first end disposed in the bore of the tube. In addition, the electrode may include a second elongated conductive member having a first end disposed in the bore and spaced from the first end of the first conductive member. For the assembly, the first and second conductive members may be held at a same voltage potential.
The present invention provides a gas discharge laser having at least one long-life elongated electrode for producing at least 12 billion high voltage electric discharges in a fluorine containing laser gas. In a preferred embodiment at least one of the electrodes is comprised of a first material having a relatively low anode erosion rate and a second anode material having a relatively higher anode erosion rate. The first anode material is positioned at a desired anode discharge region of the electrode. The second anode material is located adjacent to the first anode material along at least two long sides of the first material. During operation of the laser erosion occurs on both materials but the higher erosion rate of the second material assures that any tendency of the discharge to spread onto the second material will quickly erode away the second material enough to stop the spread of the discharge. In a preferred embodiment the anode is as described above and the cathode is also a two-material electrode with the first material at the discharge region being C26000 brass and the second material being C36000 brass. A pulse power system provides electrical pulses at rates of at least 1 KHz. A blower circulates laser gas between the electrodes at speeds of at least 5 m/s and a heat exchanger is provided to remove heat produced by the blower and the discharges.
A gas discharge laser includes a laser chamber containing a halogen laser gas, two electrode elements defining a cathode and an anode, each having a discharge receiving region defining two longitudinal edges and having a region width defining a width of an electric discharge between the electrode elements in the laser gas. The anode comprising a first anode portion comprising a first anode material defining a first anode material erosion rate, located entirely within the discharge receiving region, a pair of second 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 electrode center base portion integral with the first anode portion; and wherein each of the respective pair of second anode portions is mechanically bonded to the center base portion.
