Patents by Inventor Kazuhiko Kurata

Kazuhiko Kurata 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).

  • Publication number: 20060110107
    Abstract: The present invention provides a substrate, an optical fiber connecting end member, an optical element-housing member, a light module, and a manufacturing method of the substrate. The substrate has a feature that can be stably realizable and having a simple structure and that a light waveguide formed on the substrate surface or an optical element formed thereon can be connected without core alignment to an optical element provided on the optical fiber of the optical fiber connector to be connected to the optical fiber connecting end member. The substrate of the present invention is characterized in steps 5 for positioning being formed on at least one side of the substrate 1 that provides the optical waveguide 4.
    Type: Application
    Filed: December 29, 2005
    Publication date: May 25, 2006
    Applicant: NEC Corporation
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takanori Shimizu
  • Patent number: 6994479
    Abstract: The present invention provides a substrate, an optical fiber connecting end member, an optical element-housing member, a light module, and a manufacturing method of the substrate. The substrate has a feature that can be stably realizable and having a simple structure and that a light waveguide formed on the substrate surface or an optical element formed thereon can be connected without core alignment to an optical element provided on the optical fiber of the optical fiber connector to be connected to the optical fiber connecting end member. The substrate of the present invention is characterized in steps 5 for positioning being formed on at least one side of the substrate 1 that provides the optical waveguide 4.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: February 7, 2006
    Assignee: ′NEC Corporation
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takanori Shimizu
  • Patent number: 6964527
    Abstract: The present invention provides a substrate, an optical fiber connecting end member, an optical element-housing member, a light module, and a manufacturing method of the substrate. The substrate has a feature that can be stably realizable and having a simple structure and that a light waveguide formed on the substrate surface or an optical element formed thereon can be connected without core alignment to an optical element provided on the optical fiber of the optical fiber connector to be connected to the optical fiber connecting end member. The substrate of the present invention is characterized in steps 5 for positioning being formed on at least one side of the substrate 1 that provides the optical waveguide 4.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: November 15, 2005
    Assignee: NEC Corporation
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takanori Shimizu
  • Publication number: 20050238287
    Abstract: The present invention provides a substrate, an optical fiber connecting end member, an optical element-housing member, a light module, and a manufacturing method of the substrate. The substrate has a feature that can be stably realizable and having a simple structure and that a light waveguide formed on the substrate surface or an optical element formed thereon can be connected without core alignment to an optical element provided on the optical fiber of the optical fiber connector to be connected to the optical fiber connecting end member. The substrate of the present invention is characterized in steps 5 for positioning being formed on at least one side of the substrate 1 that provides the optical waveguide 4.
    Type: Application
    Filed: June 24, 2005
    Publication date: October 27, 2005
    Applicant: NEC Corporation
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takanori Shimizu
  • Publication number: 20050180679
    Abstract: On the back surface of a transparent plate having a light extracting part 14 for outputting lights to the outside, an electrode 16 for wiring, and an electrode 17 for an electromagnetic shield, an optical device 11 is flip-chip mounted right under the light extracting part 14, an a driver IC 12 is flip-chip mounted at a desired position with metal bumps 15. When currents driving the optical device 11 flow from the driver IC 12 according to an electric logical signal from the outside, an optical signal is emitted from the optical device 11, and is output to the outside through the light extracting part 14. The light extracting part 14 may be provided with a light coupling material or an optical axis converter.
    Type: Application
    Filed: April 18, 2003
    Publication date: August 18, 2005
    Inventors: Takanori Shimizu, Takara Sugimoto, Jun-ichi Sasaki, Kazuhiko Kurata
  • Patent number: 6901185
    Abstract: In an optical module, a package includes an array of first optical elements and at least one first positioning member. A microlens array plate including microlenses is fixed to the package, so that each of the microlenses corresponds to one of the first optical elements. An optical array connector mounts second optical elements thereon. The optical array connector has a light path bending portion for bending light paths of the second optical elements and at least one second positioning member. The optical array connector abuts against the package by aligning the second positioning member to the first positioning member so that each of the first optical elements corresponds to one of the second optical elements, A clamping member clamps the optical, array connector to the package.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: May 31, 2005
    Assignee: NEC Corporation
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takashi Yoshikawa
  • Patent number: 6696755
    Abstract: A semiconductor device comprises: an insulating flexible film capable of changing its profile; first and second conductive layers provided on both surfaces of the flexible film and constituting wiring patterns; an LSI mounted on the first conductive layer; a conductor provided in a hole formed in the flexible film and making connection between the wiring pattern formed in the first conductive layer and the wiring pattern formed in the second wiring pattern; a stiffener; and a heat spreader. A part of the wiring pattern constituted by each of the first conductive layer and the second wiring pattern is a conductive wiring, whose characteristic impedance is previously calculated, for a high-speed signal and a connection portion for making connection to a mother board is provided on an end of the conductive wiring for a high-speed signal.
    Type: Grant
    Filed: March 14, 2003
    Date of Patent: February 24, 2004
    Assignee: NEC Corporation
    Inventors: Nobuharu Kami, Kazuhiko Kurata, Satoshi Doumae, Takara Sugimoto
  • Patent number: 6663295
    Abstract: An optical transmitter-receiver module includes: an electrically conductive platform substrate having a transmitter region and a receiver region; a first insulating film extending over the transmitter region and the receiver region of the electrically conductive platform substrate; a first electrically conductive layer having a first fixed-potential, and the first electrically conductive layer extending over the first insulating film; a second insulating film selectively extending over the first electrically conductive layer; an optical receiver circuit including a light-receiving device and existing over the second insulating film; an optical transmitter circuit including a light-emitting device existing on the first insulating film; and a first electrically conductive shielding member spatially isolating the optical receiver circuit from the optical transmitter circuit, and being electrically coupled to the first electrically conductive layer.
    Type: Grant
    Filed: January 28, 2002
    Date of Patent: December 16, 2003
    Assignee: NEC Corporation
    Inventors: Nobuharu Kami, Kazuhiko Kurata, Mikio Oda
  • Publication number: 20030173663
    Abstract: A semiconductor device comprises: an insulating flexible film capable of changing its profile; first and second conductive layers provided on both surfaces of the flexible film and constituting wiring patterns; an LSI mounted on the first conductive layer; a conductor provided in a hole formed in the flexible film and making connection between the wiring pattern formed in the first conductive layer and the wiring pattern formed in the second wiring pattern; a stiffener; and a heat spreader. A part of the wiring pattern constituted by each of the first conductive layer and the second wiring pattern is a conductive wiring, whose characteristic impedance is previously calculated, for a high-speed signal and a connection portion for making connection to a mother board is provided on an end of the conductive wiring for a high-speed signal.
    Type: Application
    Filed: March 14, 2003
    Publication date: September 18, 2003
    Applicant: NEC CORPORATION
    Inventors: Nobuharu Kami, Kazuhiko Kurata, Satoshi Doumae, Takara Sugimoto
  • Publication number: 20030138223
    Abstract: In an optical module, a package includes an array of first optical elements and at least one first positioning member. A microlens array plate including microlenses is fixed to the package, so that each of the microlenses corresponds to one of the first optical elements.
    Type: Application
    Filed: January 15, 2003
    Publication date: July 24, 2003
    Applicant: NEC CORPORATION
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takashi Yoshikawa
  • Publication number: 20030091303
    Abstract: An optical transmitter-receiver module includes: an electrically conductive platform substrate having a transmitter region and a receiver region; a first insulating film extending over the transmitter region and the receiver region of the electrically conductive platform substrate; a first electrically conductive layer having a first fixed-potential, and the first electrically conductive layer extending over the first insulating film; a second insulating film selectively extending over the first electrically conductive layer; an optical receiver circuit including a light-receiving device and existing over the second insulating film; an optical transmitter circuit including a light-emitting device existing on the first insulating film; and a first electrically conductive shielding member spatially isolating the optical receiver circuit from the optical transmitter circuit, and being electrically coupled to the first electrically conductive layer.
    Type: Application
    Filed: January 28, 2002
    Publication date: May 15, 2003
    Applicant: NEC CORPORATION
    Inventors: Nobuharu Kami, Kazuhiko Kurata, Mikio Oda
  • Publication number: 20020085254
    Abstract: An optical transceiver having a transmitter section and a receiver section formed on a substrate to be close to each other is provided, which suppresses the electrical and optical crosstalk between the transmitter section and the receiver section. The transceiver comprises: (a) a substrate; (b) a transmitter section formed on the substrate and including a light-emitting element; (c) a receiver section formed on the substrate to be close to the transmitter section and including a light-receiving element; (d) a conductive first connection member fixed near the substrate; and (e) a transparent second connection member fixed near the first member in such a way as to block the first opening and the second opening of the first member from a front of the first member. The first member has a first opening that allows a first light beam to penetrate the first member and a second opening that allows a second light beam to penetrate the first member.
    Type: Application
    Filed: December 27, 2001
    Publication date: July 4, 2002
    Applicant: NEC CORPORATION
    Inventors: Kazuhiko Kurata, Nobuharu Kami
  • Publication number: 20010041034
    Abstract: The present invention provides a substrate, an optical fiber connecting end member, an optical element-housing member, a light module, and a manufacturing method of the substrate. The substrate has a feature that can be stably realizable and having a simple structure and that a light waveguide formed on the substrate surface or an optical element formed thereon can be connected without core alignment to an optical element provided on the optical fiber of the optical fiber connector to be connected to the optical fiber connecting end member. The substrate of the present invention is characterized in steps 5 for positioning being formed on at least one side of the substrate 1 that provides the optical waveguide 4.
    Type: Application
    Filed: May 10, 2001
    Publication date: November 15, 2001
    Inventors: Junichi Sasaki, Kazuhiko Kurata, Takanori Shimizu
  • Patent number: 5917200
    Abstract: An Au layer 3 and a Sn layer 5 are laminated on a barrier layer 8 which is formed on an optical circuit substrate 1. An Au layer 5 having a predetermined thickness is formed on the laminated layers as a top layer. A junction portion 2 is constituted of these layers. An electrode layer of an optical semiconductor element 9 is made to contact with the top Au layer 5 and the optical semiconductor element 9 is pressed to the optical circuit substrate 1. Then, by heating, the optical semiconductor element 9 is joined on the optical circuit substrate. A weight % of Au and Sn in the junction portion 2 of the optical circuit substrate 1 is about 80%:20% before the joining. The electrode layer is formed as a thin Au layer. The optical circuit substrate 1 is heated at a temperature of 280.degree. C. or more such that the Au layer and the Sn layer are melted and is cooled such that Au and Sn are solidified.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: June 29, 1999
    Assignee: NEC Corporation
    Inventor: Kazuhiko Kurata
  • Patent number: 5854087
    Abstract: A process wherein a Au layer 3 and a Sn layer 5 are laminated on a barrier layer 8 which is formed on an optical circuit substrate 1. An Au layer 5 having a predetermined thickness is formed on the laminated layers as a top layer. A junction portion 2 is constituted of these layers. An electrode layer of an optical semiconductor element 9 is made to contact with the top Au layer 5 and the optical semiconductor element 9 is pressed to the optical circuit substrate 1. Then, by heating, the optical semiconductor element 9 is joined on the optical circuit substrate. A weight % of Au and Sn in the junction portion 2 of the optical circuit substrate 1 is about 80%:20% before the joining. The electrode layer is formed as a thin Au layer. The optical circuit substrate 1 is heated at a temperature of 280.degree. C. or more such that the Au layer and the Sn layer are melted and is cooled such that Au and Sn are solidified.
    Type: Grant
    Filed: April 29, 1996
    Date of Patent: December 29, 1998
    Assignee: NEC Corporation
    Inventor: Kazuhiko Kurata
  • Patent number: 5799120
    Abstract: In a waveguide type wavelength multiplexing/demultiplexing (WDM) module, a wavelength multiplexing/demultiplexing function can be realized with a half length of the conventional directional coupling device. The waveguide type WDM module is comprised of: a common waveguide for conducting first signal light having a first wavelength and second signal light having a second wavelength; common light input/output means coupled to the common waveguide; a substrate containing a WDM unit for multiplexing/demultiplexing the first signal light and the second signal light; a first waveguide for conducting the first signal light; first light input/output means optically coupled to the first waveguide; and second light input/output means for inputting/outputting the second signal light. The WDM unit includes a directional coupling type WDM device constituted by two sets of waveguides connected to the first waveguide and the common waveguide respectively.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: August 25, 1998
    Assignee: NEC Corporation
    Inventors: Kazuhiko Kurata, Naoki Kimura
  • Patent number: 5668902
    Abstract: In a coupling structure for directly coupling a semiconductor laser to an optical fiber without using a lens, a coupling structure is provided which is superior in producibility, low in coupling loss and stable in operation of the semiconductor laser, by removing an influence of a return light due to Fresnel reflection from an end face of the optical fiber. A re-combination of the semiconductor laser to an active layer of the optical fiber is prevented by scattering a reflection light at the end face of the optical fiber by positively increasing a surface roughness Rz of the end face of the optical fiber to a range from 0.04 .mu.m to 0.06 .mu.m. The end face is formed by cutting the optical fiber with a blade saw having abrasive of particle size in a range from #1000 gauge to #2000 gauge corresponding to a range from 8 .mu.m to 20 .mu.m. The end face may be polished with abrasive having size in a rage from #1000 to #2000 gauge.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: September 16, 1997
    Assignee: NEC Corporation
    Inventor: Kazuhiko Kurata
  • Patent number: 5633962
    Abstract: The object is to reduce the size and losses of light transmitting/receiving modules. An optical transmitting/receiving module according to the invention comprises a light emitting element for sending out an optical signal of .lambda..sub.1 in wavelength, a first optical waveguide into which this transmit optical signal is entered, and a second optical waveguide for sending out the transmit optical signal and receiving an optical signal of .lambda..sub.2 in wavelength. Characteristically, it has a directional coupling section formed by arranging the first and second optical waveguides close to each other to be half as long as the full coupling length for a light having the wavelength of .lambda..sub.1, and at the end of the directional coupling section are arranged a filter for reflecting the transmit optical signal of .lambda..sub.1 in wavelength and transmitting the receive optical signal of .lambda..sub.
    Type: Grant
    Filed: December 12, 1994
    Date of Patent: May 27, 1997
    Assignee: NEC Corporation
    Inventor: Kazuhiko Kurata
  • Patent number: 5617495
    Abstract: Semiconductor device can be connected to an external optical fiber, by providing a short optical fiber, optically coupled to a semiconductor, which is held in a ferrule having the same diameter as an external ferrule of the external fiber. The semiconductor device comprises an optical semiconductor laser diode, a short optical fiber optically coupling at its first end face with the optical semiconductor laser diode, a ferrule for housing the optical fiber, and a sleeve which has an inner diameter slightly larger than an outer diameter of the ferrule and into which the ferrule is inserted. The connection to an external optical fiber is given by inserting a connector of the external optical fiber into the sleeve. The present invention provides compact optical semiconductor device suitable for automatic mounting thereof.
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: April 1, 1997
    Assignee: NEC Corporation
    Inventors: Masaaki Funabashi, Kazuhiko Kurata
  • Patent number: 5479549
    Abstract: In a coupling structure for directly coupling a semiconductor laser to an optical fiber without using a lens, a coupling structure is provided which is superior in producibility, low in coupling loss and stable in operation of the semiconductor laser, by removing an influence of a return light due to Fresnel reflection from an end face of the optical fiber. A re-combination of the semiconductor laser to an active layer of the optical fiber is prevented by scattering a reflection light at the end face of the optical fiber by positively increasing a surface roughness Rz of the end face of the optical fiber to a range from 0.04 .mu.m to 0.06 .mu.m. The end face is formed by cutting the optical fiber with a blade saw having abrasive of particle size in a range from #1000 gauge to #2000 gauge corresponding to a range from 8 .mu.m to 20 .mu.m. The end face may be polished with abrasive having size in a rage from #1000 to #2000 gauge.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: December 26, 1995
    Assignee: NEC Corporation
    Inventor: Kazuhiko Kurata