Patents by Inventor Tomohiro Sasagawa

Tomohiro Sasagawa 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: 6008914
    Abstract: The laser transfer machining apparatus comprises a shaping unit for shaping the laser beam so that the laser beam has a beam pattern which corresponds to a desired pattern to be machined in the object to be machined and a generating unit disposed separately from the shaping unit for simultaneously generating a plurality of laser beams each having the beam pattern from the laser beam shaped by the shaping unit. The generating unit is adapted to emit the plural laser beams while simultaneously defining a plurality of radiation directions of the generated plural laser beams to the object to be machined. The laser transfer machining apparatus can provide a high efficiency of utilization of light and reduce the time required for machining. Furthermore, the laser transfer machining apparatus can utilize a laser with a relatively low spatially coherence such as an eximer laser.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: December 28, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tomohiro Sasagawa, Kenyu Haruta, Yukio Sato, Hitoshi Wakata, deceased, Mitsuo Inoue, Akihiro Suzuki, Shuichi Fujikawa, Yoshio Saito
  • Patent number: 5305338
    Abstract: A switch device used for a laser device, includes series-parallel connected switch elements or modules. The switch elements or modules are simultaneously turned on by trigger signals from trigger circuits. The transmission lines for connecting the trigger circuits to respective switch elements are equal to one another in length. A protecting circuit is provided for the switch elements, and indicators are provided for indicating the shortcircuit of the switch elements. In the switch device, the number of wires for the switch elements is made small and heat generated from the switch elements is effectively radiated. The modules are easily stacked, and firmly connected to a control unit for controlling the switch elements. A discharge excited laser device using the switch device has a high efficiency and a long lifetime and is reliable.
    Type: Grant
    Filed: September 10, 1991
    Date of Patent: April 19, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hitoshi Wakata, Akihiro Suzuki, Kenyu Haruta, Haruhiko Nagai, Akihiko Iwata, Shinji Murata, Isamu Tanakura, Tomohiro Sasagawa, Yuito Kimura
  • Patent number: 5258994
    Abstract: A discharge-excited laser apparatus includes a pair of discharge electrodes extending in a direction of an optical axis; a plurality of charging capacitors charged by a power source; a plurality of peaking capacitors arranged in parallel in a longitudinal direction of the discharge electrodes and receiving energy accumulated in the charging capacitors; and a plurality of semiconductor switches arranged with conductive plates in the longitudinal direction of the discharge electrodes and connected in series and in parallel to the peaking capacitors. The construction of the semiconductor switches enables uniform shift of the energy in the charging capacitors to the peaking capacitors and reduction of inductance of a loop for capacity shifting.
    Type: Grant
    Filed: June 19, 1991
    Date of Patent: November 2, 1993
    Assignee: Mitsubishi Denki K.K.
    Inventors: Kenyu Haruta, Akihiro Suzuki, Akihiko Iwata, Yasushi Minamitani, Hitoshi Wakata, Tomohiro Sasagawa, Takashi Kumagai