Patents by Inventor Hakaru Mizoguchi

Hakaru Mizoguchi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6130904
    Abstract: In an excimer laser apparatus in which halogen gas, rare gas and buffer gas are fed into the laser chamber, before laser oscillation, the oscillation stop time is calculated, and, if the calculated oscillation stop time exceeds a prescribed time, the calculated oscillation stop time is used to calculate a feeding amount of mixed gas comprising rare gas or buffer gas, and the mixed gas is fed, prior to laser oscillation, in the calculated feeding amount; stable laser output is thereby obtained from the initial period of laser oscillation.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: October 10, 2000
    Assignee: Komatsu Ltd.
    Inventors: Takanobu Ishihara, Junichi Fujimoto, Hakaru Mizoguchi
  • Patent number: 6101211
    Abstract: A narrow-band laser apparatus comprising a laser generating section having laser activity and capable of generating laser beam; bandwidth narrowing section which is provided on one end side of the laser generating section on the optical axis of the laser beam generated in the laser generating section to narrow the bandwidth of the laser beam by means of at least one angel-dispersion wavelength selection element, fold back the laser beam in the narrowed band and output the folded laser beam toward the laser generating section; beam folding section which is provided on the other end of the laser generating section on the optical axis of the laser beam generated in the laser generating section to fold back the input laser beam and reflect the folded laser beam into the laser generating section; and a laser beam branching unit which is provided between the laser generating section and the bandwidth narrowing section to permit part of the laser beam input from the laser generating section to pass therethrough into
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: August 8, 2000
    Assignee: Komatsu, Ltd.
    Inventors: Osamu Wakabayashi, Hiroshi Komori, Hakaru Mizoguchi
  • Patent number: 6008497
    Abstract: A laser apparatus comprises storage means for storing a power source voltage of each pulse at the time of continuous pulse oscillation for one cycle, with each voltage correlated with an identifier which specifies the respective pulse, and output control means for, when a pulse is generated, reading from the storage means the source voltage of a pulse having the same identifier, and performing pulse oscillation on the basis of the source voltage. Thus the influence of the spiking phenomenon during a burst mode operation is eliminated as much as possible, and thereby the accuracy of laser beam machining is still more improved.
    Type: Grant
    Filed: February 25, 1998
    Date of Patent: December 28, 1999
    Assignee: Komatsu Ltd.
    Inventors: Hakaru Mizoguchi, Osamu Wakabayashi, Yukio Kobayashi, Yoshiho Amada, Tatsuo Mimura
  • Patent number: 5754579
    Abstract: A first object is to stabilize output of laser light. In order to achieve the first object, if it is detected by an output detection means (15) that the output (E) of laser light (La) has departed from a target value, whilst maintaining the voltage of a power source (17) at a fixed value or in a fixed range, the amount of laser gas supplied to a laser chamber (4) is controlled such that the output (E) of laser light becomes the target value. A second object is to reduce the wear of the pre-ionization electrodes and to prevent drop in output of laser light. The second object is achieved as follows. Specifically, the pulse current discharged from primary capacitor (C1) is stepped up in voltage by a pulse transformer and is charged onto a secondary capacitor (C2).
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: May 19, 1998
    Assignee: Komatsu Ltd.
    Inventors: Hakaru Mizoguchi, Toshihiro Nishisaka, Hiroshi Komori
  • Patent number: 5663977
    Abstract: A gas laser apparatus is operated in such a manner that gas supplied to a laser chamber is excited for laser oscillation. A cabinet (11) which houses gas containers (12 and 13) is located adjacent to the laser oscillator (1) or integrated with it, The piping for the laser gas is incorporated in the cabinet, Such a structure realizes an economical laser of stabilized performance and easy maintenance.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: September 2, 1997
    Assignee: Komatsu Ltd.
    Inventors: Junichi Fujimoto, Hakaru Mizoguchi
  • Patent number: 5642374
    Abstract: Aimed at preventing a laser light beam profile from fluctuating, and by using the fact that there is a substantially proportional relation between the beam profile and the charging voltage as well as between the beam profile and the composition or the total pressure of the laser gases, an excimer laser device comprises a laser chamber containing laser gases which are excited by initiating an electric discharge in the laser chamber to output laser light, a beam profile detector for detecting a beam profile of the output laser light, and a controller for controlling a electric discharge voltage (excitation intensity) and composition or total pressure of the prescribed types of laser gases in such a way that the beam profile is shaped as desired based on detection results of the beam profile detector.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: June 24, 1997
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Osamu Wakabayashi, Hakaru Mizoguchi
  • Patent number: 5557629
    Abstract: A laser device is capable reducing fluctuation of the beam width of the output laser beam due to abrasion of its discharge electrodes. A part of the contour shape of a section perpendicular to the longitudinal axis of the chamber of the laser device in at least one of the electrodes, which part confronts the other one of the electrodes, has a shape of a circular arc having a predetermined radius. The width of at least one of the two electrode may be substantially equal to the width of electric discharge taken place between the electrodes. Further, a conductor member may be disposed on each side of the electrode along its longitudinal axis to reduce electric field strength therearound.
    Type: Grant
    Filed: August 28, 1992
    Date of Patent: September 17, 1996
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Hakaru Mizoguchi, Yoshiho Amada, Noritoshi Ito
  • Patent number: 5535233
    Abstract: A laser device is capable reducing fluctuation of the beam width of the output laser beam due to abrasion of its discharge electrodes. A part of the contour shape of a section perpendicular to the longitudinal axis of the chamber of the laser device in at least one of the electrodes, which part confronts the other one of the electrodes, has a shape of a circular arc having a predetermined radius. The width of at least one of the two electrode may be substantially equal to the width of electric discharge taken place between the electrodes. Further, a conductor member may be disposed on each side of the electrode along its longitudinal axis to reduce electric field strength therearound.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: July 9, 1996
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Hakaru Mizoguchi, Yoshiho Amada, Noritoshi Ito
  • Patent number: 5450436
    Abstract: A laser system which realizes its stable operation. In the system, a spectrum width of laser light dischargingly excited in a laser chamber is detected by a spectrum width monitor. A controller controls, on the basis of the detected spectrum width, a replenishment amount of gas to be replenished from an F2 gas cylinder into the laser chamber through a sub-tank and on-off valves to cause the spectrum width to become constant.Further, when replenishment of a halogen gas diluted with a buffer gas is carried out, a gas exhaustion step of keeping the internal total gas pressure of the laser chamber constant is omitted.In addition, a laser oscillation pulse number is counted for a predetermined period of time and a replenishment amount of the halogen gas is carried out according to the count value.
    Type: Grant
    Filed: November 19, 1993
    Date of Patent: September 12, 1995
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Hakaru Mizoguchi, Junichi Fujimoto, Masahiko Kowaka, Tomokazu Takahashi
  • Patent number: 5373523
    Abstract: An excimer laser apparatus is provided with a compact high efficiency dust particle removal means which is capable of maintaining the windows clean with only a small volume of purging gas, and which prevents deterioration of aperture masks without having to increase the cavity length or risking the possibility of leakage from piping connections. The excimer laser apparatus uses, as dust particle removal means, filters (13a and 13b) made of metal or ceramic which is non-reactive with fluorine. A ground potential dust collector can be provided at a downstream side of a static dust particle remover, having an anode and a cathode, for collecting any dust particles which have passed through the static dust particle remover.
    Type: Grant
    Filed: October 14, 1993
    Date of Patent: December 13, 1994
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Junichi Fujimoto, Hakaru Mizoguchi, Yoshiho Amada, Osamu Wakabayashi
  • Patent number: 5291509
    Abstract: A gas laser apparatus in which a gas medium in a case and a lubricant for bearings supporting a blower for circulating the gas medium are isolated from each other, so that the lubricant can be prevented from mixing into the gas medium while no substantially large resistance is applied to the blower drive. To isolate the gas medium and the lubricant, magnetic fluid shaft seals (10, 11) are used for sealing between the lubricant for the bearings (6) for supporting rotation shafts (3a, 3b) of the blower (3) and the gas medium in the case (1).
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: March 1, 1994
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Hakaru Mizoguchi, Junichi Fujimoto, Yoshiho Amada
  • Patent number: 4745614
    Abstract: A silent discharge type laser device which comprises a detector for detecting the amount of electric charges passed between electrodes and controlling means for controlling an output current or voltage of a power supply so that a charge amount detected by the detector is equal to a target level, thereby keeping the passage charge amount always constant.
    Type: Grant
    Filed: August 20, 1986
    Date of Patent: May 17, 1988
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Akira Egawa, Hakaru Mizoguchi, Kiyonori Matsuno, Tatsuya Ariga, Ryoichi Nodomi
  • Patent number: 4571730
    Abstract: In a cross flow type laser device of the type comprising a cylindrical vacuum vessel, guide ducts for defining a laser medium circulating path, a fan for circulating the laser medium through the circulating path, discharge electrodes installed in the vacuum vessel for creating electrode discharge through circulating laser medium and a cooler for cooling the circulating laser medium, the fan is constructed as a cross-flow fan utilizing a portion of the inner wall of the vessel as a rear casing and a portion of the guide ducts as a front casing so that the fan has substantially the same axial length as that of the cylindrical vacuum vessel.
    Type: Grant
    Filed: February 16, 1984
    Date of Patent: February 18, 1986
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Hakaru Mizoguchi, Akira Egawa, Akira Okamoto