Patent ID: 6529538
Filing Date: 2003-03-04
Classification: H01S

Abstract:
A gas laser oscillator apparatus comprising:a first main discharge electrode and a second main discharge electrode positioned to face with each other; a pair of preliminary ionization electrodes comprised of hollow dielectric pipes, rear electrodes placed in hollow interiors of said dielectric pipes, and corona electrodes positioned so as to be in contact with outer surfaces of said dielectric pipes, that are positioned at sides of said first main discharge electrode, among said first and second main discharge electrodes, so as to sandwich said first main discharge electrode therebetween, leaving prescribed gaps between said first main discharge electrode and themselves, respectively, and that generate corona discharges started at points of contact as starting points between said corona electrodes and said dielectric pipes, by application of a high voltage across said corona electrodes and said rear electrodes, so as to produce preliminary ionization in a main discharge space; a support plate for securing and supporting said first main discharge electrode and said pair of preliminary ionization electrodes; and laser gas that flows from a side of one of said preliminary ionization electrodes toward a side of other of the preliminary ionization electrodes through said main discharge space between said first and second main discharge electrodes; said corona electrodes being positioned such that the starting points of said corona discharges on the surfaces of said dielectric pipes are lower than a height of a highest part of said first main discharge electrode, wherein the improvement comprises: portions of the corona electrodes being in contact with the dielectric pipes are formed into a plate-shape with a thickness thinner than the main discharge electrode in directions facing to the dielectric pipes; and objects are disposed in said gaps between said first main discharge electrode and said plate-shaped contact portions of the corona electrodes, from an upper surface of said support plate to the height of said starting points, for reducing an eddy of the laser gas in said gaps.