Patents by Inventor Masahide Tokuda

Masahide Tokuda 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: 7292519
    Abstract: An integrated optical head records and reproduces information to and from optical discs of different types, including CD and DVD, with use of a single information recording/reproducing apparatus. The optical head has a plurality of semiconductor lasers of different wavelengths integrated by index alignment onto a substrate formed with an optoelectric integrated circuit, photodetection patterns, and a reflecting mirror.
    Type: Grant
    Filed: January 4, 2005
    Date of Patent: November 6, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Kimio Tatsuno, Masahide Tokuda, Hirohisa Sano, Toshiaki Tanaka, Takeshi Shimano, Shigeru Nakamura, Takeshi Maeda, Akira Arimoto
  • Patent number: 6965552
    Abstract: A method of mounting an optical device having a step on the surface opposing to a mounting substrate favorably by face-down bonding which enables a decrease in the number of components or integrate additional components on one identical substrate and, accordingly, is useful for reducing the size and the thickness of an optical head using a light source, the method includes the step of making the volume of a solder pattern to the area ratio of each electrode different for every wiring electrode portions upon mounting the electrodes on the substrate for mounting the optical device, in which the optical device having the step can be mounted favorably to the substrate by the control for the height of solder upon melting.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: November 15, 2005
    Assignees: Hitachi, Ltd., Nichia Corporation
    Inventors: Masahide Tokuda, Kimio Tatsuno, Hirohisa Sano, Takeshi Shimano, Shigeharu Kimura
  • Publication number: 20050122880
    Abstract: An integrated optical head records and reproduces information to and from optical discs of different types, including CD and DVD, with use of a single information recording/reproducing apparatus. The optical head has a plurality of semiconductor lasers of different wavelengths integrated by index alignment onto a substrate formed with an optoelectric integrated circuit, photodetection patterns, and a reflecting mirror.
    Type: Application
    Filed: January 4, 2005
    Publication date: June 9, 2005
    Inventors: Kimio Tatsuno, Masahide Tokuda, Hirohisa Sano, Toshiaki Tanaka, Takeshi Shimano, Shigeru Nakamura, Takeshi Maeda, Akira Arimoto
  • Patent number: 6829265
    Abstract: The subject of the disclosed art is to prevent a short circuit between plural electrodes caused by soldering in the assembling process for a semiconductor laser element. The constitution for improving the subject is as follows. A semiconductor laser device comprises a semiconductor laser chip having a first electrode and a laser sustaining material, in which the laser sustaining material has electrodes and solder layers connected electrically therewith on the surface where the semiconductor laser chip is mounted, the first electrode of the semiconductor laser chip is connected with the solder layer of the laser sustaining material and at least the solder layer of the laser sustaining material extends from at least one end face in the longitudinal direction of an optical resonator of the semiconductor laser chip to the outside of the optical resonator.
    Type: Grant
    Filed: May 15, 2002
    Date of Patent: December 7, 2004
    Assignees: Hitachi, Ltd., Hitachi Printing Solutions Ltd.
    Inventors: Shinichi Nakatsuka, Susumu Saito, Junshin Sakamoto, Kazuo Sakaki, Masahide Tokuda
  • Patent number: 6782018
    Abstract: This invention is provided to reduce wavefront aberrations caused by the filling of a transparent resin intended to prevent degradation of a diode laser in a hermetically sealed package. A parallel-plane plate is arranged between a diode laser and an objective lens, and a transparent resin is filled into a space formed between the diode laser and the parallel-plane plate. With this invention, degradations of the diode lasers can be prevented and the wavefront aberrations can be reduced.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: August 24, 2004
    Assignee: Hitachi, Litd.
    Inventors: Kimio Tatsuno, Masahide Tokuda, Shigeharu Kimura, Takeshi Shimano, Hirohisa Sano
  • Publication number: 20030147333
    Abstract: A method of mounting an optical device having a step on the surface opposing to a mounting substrate favorably by face-down bonding which enables a decrease in the number of components or integrate additional components on one identical substrate and, accordingly, is useful for reducing the size and the thickness of an optical head using a light source, the method typically includes the step of making the area ratio of each electrode to a solder pattern different for every wiring electrode portions upon mounting the electrodes on the substrate for mounting the optical device, in which the optical device having the step can be mounted favorably to the substrate by the control for the height of solder upon melting, and the volume of the solder is previously controlled depending on the wettability of a region of the substrate covered by the solder.
    Type: Application
    Filed: February 27, 2002
    Publication date: August 7, 2003
    Inventors: Masahide Tokuda, Kimio Tatsuno, Hirohisa Sano, Takeshi Shimano, Shigeharu Kimura
  • Publication number: 20030128726
    Abstract: This invention is provided to reduce wavefront aberrations caused by the filling of a transparent resin intended to prevent degradation of a diode laser in a hermetically sealed package. A parallel-plane plate is arranged between a diode laser and an objective lens, and a transparent resin is filled into a space formed between the diode laser and the parallel-plane plate. With this invention, degradations of the diode lasers can be prevented and the wavefront aberrations can be reduced.
    Type: Application
    Filed: February 26, 2002
    Publication date: July 10, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Kimio Tatsuno, Masahide Tokuda, Shigeharu Kimura, Takeshi Shimano, Hirohisa Sano
  • Publication number: 20020172245
    Abstract: The subject of the disclosed art is to prevent a short circuit between plural electrodes caused by soldering in the assembling process for a semiconductor laser element. The constitution for improving the subject is as follows. A semiconductor laser device comprises a semiconductor laser chip having a first electrode and a laser sustaining material, in which the laser sustaining material has electrodes and solder layers connected electrically therewith on the surface where the semiconductor laser chip is mounted, the first electrode of the semiconductor laser chip is connected with the solder layer of the laser sustaining material and at least the solder layer of the laser sustaining material extends from at least one end face in the longitudinal direction of an optical resonator of the semiconductor laser chip to the outside of the optical resonator.
    Type: Application
    Filed: May 15, 2002
    Publication date: November 21, 2002
    Inventors: Shinichi Nakatsuka, Susumu Saito, Junshin Sakamoto, Kazuo Sakaki, Masahide Tokuda
  • Patent number: 5870289
    Abstract: A structure for connecting an integrated circuit chip to a wiring substrate which implements high-density packaging, high-density connection, high-speed signal transmission, and low cost. An integrated circuit is connected to a wiring substrate by means of flip-chip die bonding using an adhesive film. A direct through-hole connection is formed directly below a connecting pad so as to pass through the adhesive film and the wiring substrate. This direct through-hole connection directly connects the connecting pad to the wire. As a result of reduced area and thickness of the chip, the chip is mounted in high density, and high-density inputs and outputs are implemented by means of minute two-dimensional connections. Short wire connections directly connected to the chip permit high speed signal transmission, and high reliability is ensured by the dispersion of stress. Low-cost packaging can be effected by simple processes and facilities.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: February 9, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Masahide Tokuda, Takeshi Kato, Hiroyuki Itoh, Masayoshi Yagyu, Yuuji Fujita, Mitsuo Usami
  • Patent number: 5251100
    Abstract: A semiconductor integrated circuit device is equipped with a cooling system which serves to cool a plurality of integrated circuit chips mounted on a circuit board. The cooling system is kept in contact with the upper surfaces of the plurality of integrated circuit chips. A chip surface arranging plate of uniform thickness is formed with apertures smaller than the integrated circuit chips mounted on the circuit board. The cooling system is fixed on the chip surface arranging plate. The upper surfaces of the integrated circuit chips are substantially kept flush by the chip surface arranging plate. Further, the integrated circuit chips are thermally joined to the cooling system so that heat generated by the integrated circuit chips is removed by the cooling system. The plurality of integrated circuit chips are joined to the chip surface arranging plate by applying a vacuum that causes suction of air through the apertures formed in the chip surface arranging plate.
    Type: Grant
    Filed: August 25, 1992
    Date of Patent: October 5, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Yuuji Fujita, Masahide Tokuda
  • Patent number: 4819857
    Abstract: A method for fabricating a composite structure, in which an intermediate member is sandwiched between first and second members, is disclosed. In this method, the intermediate member is disposed along the periphery of a spatial region formed between facing surfaces of the first and second members so that the spatial region is enclosed by the intermediate member, the fluidity of the intermediate member is enhanced under an atmosphere having a predetermined pressure, and then the pressure of the atmosphere is increased to make the intermediate member flow into the spatial region.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: April 11, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Mizuishi, Masahide Tokuda, Katuaki Chiba
  • Patent number: 4686606
    Abstract: A cooling structure for cooling a multichip module for effectively removing heat generated from integrated circuit chips. A suction plate formed with minute grooves on one of its surfaces is disposed between each integrated circuit chip and an associated cooling block and is brought into contact at a grooved surface with the integrated circuit chip through a layer of a liquid such as silicone oil interposed therebetween, thereby producing negative hydrostatic pressure by capillary action of the minute grooves. The suction plate has a thickness small enough to be bent under influence of the negative hydrostatic pressure to follow a warping of the integrated circuit chip, so that the clearance between the opposing surfaces of the suction plate and the integrated circuit chip can be minimized.
    Type: Grant
    Filed: February 10, 1986
    Date of Patent: August 11, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Minoru Yamada, Mitsuru Usui, Akira Masaki, Keiichirou Nakanishi, Masahide Tokuda