Patents by Inventor Daisuke Koizumi

Daisuke Koizumi 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: 20080278265
    Abstract: A signal input/output line 101 is used for input and output of a signal. A first resonating part 102 is connected to the signal input/output line 101 at one end and is opened at the other end. A second resonating part 103 is connected to a ground conductor 105 at one end and is opened at the other end. A connecting line 104 has a predetermined length and is connected to a point of connection between the signal input/output line 101 and the first resonating part 102 at one end and is connected to a predetermined point on the second resonating part 103 at the other end.
    Type: Application
    Filed: May 9, 2008
    Publication date: November 13, 2008
    Applicant: NTT DoCoMo, Inc
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi
  • Patent number: 7430798
    Abstract: An electronic component attaching tool suitable for an external shape of a semiconductor device is prepared. The electronic component attaching tool has a function of aligning a position of the semiconductor device to an IC socket. The electronic component attaching tool is mounted on the standard surface that is formed on the IC socket substantially regardless of the external shape of the semiconductor device. The semiconductor device is then aligned and attached to the IC socket by using the electronic component attaching tool, and the electronic component attaching tool is removed from the IC socket. Another electronic component attaching tool suitable for an external shape of another semiconductor device is prepared, and the same procedure as the above is performed to align and attach this semiconductor device to the same type IC socket.
    Type: Grant
    Filed: May 11, 2005
    Date of Patent: October 7, 2008
    Assignee: Fujitsu Limited
    Inventors: Daisuke Koizumi, Shigeyuki Maruyama, Kazuhiro Tashiro, Naoyuki Watanabe
  • Publication number: 20080238578
    Abstract: A coplanar waveguide resonator (100a) has a center conductor (101) formed on a dielectric substrate (105) that has a line conductor (a center line conductor) (101b) extending in the input/output direction, a ground conductor (103) that is disposed on the dielectric substrate (105) across a gap section from the center conductor (101), and a line conductor (a base stub) (104) formed as an extension line from the ground conductor (103), and a part of the base stub (104) constitutes a line conductor (a first collateral line conductor) (104a) disposed in parallel with the center line conductor (101b).
    Type: Application
    Filed: March 28, 2008
    Publication date: October 2, 2008
    Applicant: NTT DoCoMo, Inc
    Inventors: Kei Satoh, Daisuke Koizumi, Shoichi Narahashi
  • Patent number: 7403024
    Abstract: A contactor has contact electrodes elastically deformable in a direction of thickness of the contactor so that the contactor can make a contact with a semiconductor device with an appropriate contact pressure. The contactor is positioned between the semiconductor device and a test board so as to electrically connect the semiconductor device to the test board. Each of a plurality of contact electrodes has a first contact electrode part, a second contact electrode part and a connecting part electrically connecting the first contact electrode part to the second contact electrode part. The first contact electrode part contacts an electrode of the semiconductor device. The second contact electrode part contacts a terminal of the test board. A combining member has an insulating characteristic and holds the connecting part of each of the contact electrodes in a predetermined arrangement.
    Type: Grant
    Filed: July 28, 2004
    Date of Patent: July 22, 2008
    Assignee: Fujitsu Limited
    Inventors: Shigeyuki Maruyama, Kazuhiro Tashiro, Naoyuki Watanabe, Daisuke Koizumi, Takafumi Hashitani, Ei Yano
  • Patent number: 7397331
    Abstract: A coupling structure for coupling to a circuit portion (6) in a coplanar-waveguide circuit (1) having ground conductors (2, 3) at both sides is disclosed. A signal input/output line (4) is provided at the center of the coplanar-waveguide circuit; and an inductive coupling portion (5) having an end of the signal input/output line short-circuited to one of the ground conductors and facing a part of the circuit portion via a first gap is also provided.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: July 8, 2008
    Assignee: NTT DoCoMo, Inc.
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi
  • Patent number: 7378924
    Abstract: A filter is provided which comprises a single dielectric, and a line conductor and a ground conductor disposed on the dielectric. The line conductor includes first and second line conductor sections having opposed portions defining an open gap therebetween to form a capacitive coupling section. The edge lines of the opposed portions of the first and second conductor sections defining the open gap therebetween are substantially elongated relative to the line width of the corresponding conductor sections. The thus constructed filter is capable of suppressing a variation in the normalized J-inverter value even if dimensional errors relative to the design specifications due to overetching or underetching involved during the manufacture.
    Type: Grant
    Filed: February 1, 2005
    Date of Patent: May 27, 2008
    Assignee: NTT DoCoMo, Inc.
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi
  • Patent number: 7309996
    Abstract: A contactor configured to be electrically connected to the terminals of an electronic component is disclosed. The connector includes multiple contact electrodes contacting the terminals of the electronic component and multiple elastic electrodes each composed of an electrically conductive elastic body. The elastic electrodes generate a pressing force for pressing the contact electrodes against the terminals of the electronic component. The contact electrodes are separable from the elastic electrodes.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: December 18, 2007
    Assignee: Fujitsu Limited
    Inventors: Kazuhiro Tashiro, Shigeyuki Maruyama, Daisuke Koizumi, Takumi Kumatabara, Keisuke Fukuda
  • Patent number: 7307045
    Abstract: A signal switching device is disclosed that is capable of transmitting signals with less signal loss while securing a good isolation characteristic. The signal switching device includes a first section formed from a superconducting material connected to a first transmission path. The first section has a smaller cross section at the input end than at the output end or, the signal switching device may include a first section formed from a superconducting material connected to a first transmission path in series, and a second section formed from a superconducting material connected to a second transmission path in parallel. The cross section of the second section is smaller than that of the second transmission path. The length of the second transmission path is determined in such a way that an input impedance of the second transmission path is sufficiently large when the second section is in a superconducting state.
    Type: Grant
    Filed: November 7, 2003
    Date of Patent: December 11, 2007
    Assignee: NTT DoCoMo, Inc.
    Inventors: Kunihiro Kawai, Daisuke Koizumi, Kei Satoh, Shoichi Narahashi, Tetsuo Hirota
  • Patent number: 7292124
    Abstract: A variable resonator is provided which comprises signal conductor 13 formed on top side surface of dielectric substrate 12, ground conductor layer 11 formed on back side surface thereof and switches 14, wherein signal conductor comprises a plurality of first conductor lines 13-1 and second conductor line 13-2 connected with all of first conductor lines, each first conductor line has a width larger than that of second conductor line to thereby a signal path through which high-frequency electric signal passes and which is longer than length of second conductor line is provided, switches 14 are connected to the ends of first conductor lines, whereby selectively opening and closing switches will electrically disconnect and interconnect interspaces between ends of first conductor lines to thereby vary length of signal path and thus change resonance frequency.
    Type: Grant
    Filed: February 1, 2005
    Date of Patent: November 6, 2007
    Assignee: NTT DoCoMo, Inc.
    Inventors: Kunihiro Kawai, Daisuke Koizumi, Hiroshi Okazaki, Shoichi Narahashi, Yasushi Yamao
  • Publication number: 20070252608
    Abstract: A contact terminal formed of an electrically conductive material is arranged in each of a plurality of holed of a contactor substrate. An electrically conductive part is formed on an inner surface of each hole. The contact terminal has a first contact part that contacts a terminal of an electronic part and a second contact part that contacts the electrically conductive part in a middle portion. When the contact terminal bends by the first contact part being pressed, the second contact part contacts the electrically conductive part of the contactor substrate and an appropriate degree of contact pressure is obtained.
    Type: Application
    Filed: May 10, 2007
    Publication date: November 1, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Daisuke Koizumi, Naohito Kohashi, Kazuhiro Tashiro, Takumi Kumatabara
  • Publication number: 20070230450
    Abstract: A signal switching device including a plurality of transmission paths connected to an input path, the signal switching device outputting a signal from the input path through one of the transmission paths, including a first variable impedance unit connected to a first transmission path, the first variable impedance unit including a first section formed from a superconducting material, the first section being set to a non-superconducting state when the signal is to be output through a second transmission path, the first section including a portion of a predetermined length at an input end, the portion having an area of a cross section less than an area of a cross section of the first section at an output end.
    Type: Application
    Filed: March 29, 2007
    Publication date: October 4, 2007
    Applicant: NTT DoCoMo, Inc.
    Inventors: Kunihiro Kawai, Daisuke Koizumi, Kei Satoh, Shoichi Narahashi, Tetsuo Hirota
  • Publication number: 20070223202
    Abstract: A planar circuit housing (300) for containing a planar circuit (120) is disclosed. The planar circuit housing (300) comprises a support portion (341) for supporting edges of the planar circuit (120), the support portion (341) being provided on at least one housing internal surface substantially perpendicular to the planar circuit substrate (120); an upper cavity (380) in the housing (300) above the planar circuit (120); and a lower cavity (382) in the housing (300) below the planar circuit (120), the lower cavity (382) having the same sizes as the upper cavity (380) in directions parallel with the planar circuit substrate (120).
    Type: Application
    Filed: September 19, 2005
    Publication date: September 27, 2007
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi, Tatsuro Masamura
  • Publication number: 20070052502
    Abstract: A coplanar resonator which is comprised of a dielectric substrate, a center conductor formed in the surface thereof, and a ground conductor formed so as to surround the same center conductor, wherein the same center conductor is comprised of a main line conductor 31, formed by extension in a rectilinear shape, and auxiliary line conductors 32a and 32b bifurcating from at least one end of the same main line conductor, folding back and being extended on both sides of the main line conductor.
    Type: Application
    Filed: September 1, 2006
    Publication date: March 8, 2007
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi
  • Patent number: 7161449
    Abstract: A center conductor having a length L1, which is equivalent in electrical length to one quarter wavelength, and ground conductors disposed on the opposite sides of the center conductor with a gap portion therebetween in coplanar manner are formed on a dielectric substrate. The center conductor and the ground conductors located on the opposite sides thereof, and are connected together by shorting ends. This results in the formation of corner areas, respectively, whereby obtaining a coplanar waveguide resonator. An edge line of the shorting end is recessed to have a curve configuration so that each corner area has an angle greater than 90 degrees, which reduces power current concentration at the corner points in the respective corner areas.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: January 9, 2007
    Assignee: NTT DoCoMo, Inc.
    Inventors: Kei Satoh, Shoichi Narahashi, Daisuke Koizumi, Yasushi Yamao
  • Publication number: 20060193559
    Abstract: A coupling structure for coupling to a circuit portion (6) in a coplanar-waveguide circuit (1) having ground conductors (2, 3) at both sides is disclosed. A signal input/output line (4) is provided at the center of the coplanar-waveguide circuit; and an inductive coupling portion (5) having an end of the signal input/output line short-circuited to one of the ground conductors and facing a part of the circuit portion via a first gap is also provided.
    Type: Application
    Filed: February 9, 2006
    Publication date: August 31, 2006
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi
  • Publication number: 20050204551
    Abstract: An electronic component attaching tool suitable for an external shape of a semiconductor device is prepared. The electronic component attaching tool has a function of aligning a position of the semiconductor device to an IC socket. The electronic component attaching tool is mounted on the standard surface that is formed on the IC socket substantially regardless of the external shape of the semiconductor device. The semiconductor device is then aligned and attached to the IC socket by using the electronic component attaching tool, and the electronic component attaching tool is removed from the IC socket. Another electronic component attaching tool suitable for an external shape of another semiconductor device is prepared, and the same procedure as the above is performed to align and attach this semiconductor device to the same type IC socket.
    Type: Application
    Filed: May 11, 2005
    Publication date: September 22, 2005
    Applicant: Fujitsu Limited
    Inventors: Daisuke Koizumi, Shigeyuki Maruyama, Kazuhiro Tashiro, Naoyuki Watanabe
  • Publication number: 20050206481
    Abstract: A filter is provided which comprises a single dielectric, and a line conductor and a ground conductor disposed on the dielectric. The line conductor includes first and second line conductor sections having opposed portions defining an open gap therebetween to form a capacitive coupling section. The edge lines of the opposed portions of the first and second conductor sections defining the open gap therebetween are substantially elongated relative to the line width of the corresponding conductor sections. The thus constructed filter is capable of suppressing a variation in the normalized J-inverter value even if dimensional errors relative to the design specifications due to overetching or underetching involved during the manufacture.
    Type: Application
    Filed: February 1, 2005
    Publication date: September 22, 2005
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Koizumi, Kei Satoh, Shoichi Narahashi
  • Publication number: 20050190018
    Abstract: A variable resonator is provided which comprises signal conductor 13 formed on top side surface of dielectric substrate 12, ground conductor layer 11 formed on back side surface thereof and switches 14, wherein signal conductor comprises a plurality of first conductor lines 13-1 and second conductor line 13-2 connected with all of first conductor lines, each first conductor line has a width larger than that of second conductor line to thereby a signal path through which high-frequency electric signal passes and which is longer than length of second conductor line is provided, switches 14 are connected to the ends of first conductor lines, whereby selectively opening and closing switches will electrically disconnect and interconnect interspaces between ends of first conductor lines to thereby vary length of signal path and thus change resonance frequency.
    Type: Application
    Filed: February 1, 2005
    Publication date: September 1, 2005
    Applicant: NTT DoCoMo, Inc.
    Inventors: Kunihiro Kawai, Daisuke Koizumi, Hiroshi Okazaki, Shoichi Narahashi, Yasushi Yamao
  • Patent number: 6927343
    Abstract: A contactor has a film substrate of an insulating material and plural wiring patterns on the substrate. A first end of each wiring pattern extends out from a first edge of the substrate as a first contact terminal and a second end of each wiring pattern extends out from a second edge of the substrate as a second contact terminal, and a part of the contactor located between the first end and second end can be deformed resiliently.
    Type: Grant
    Filed: October 9, 2002
    Date of Patent: August 9, 2005
    Assignee: Fujitsu Limited
    Inventors: Naoyuki Watanabe, Shigeyuki Maruyama, Kazuhiro Tashiro, Daisuke Koizumi, Takafumi Hashitani
  • Patent number: 6924174
    Abstract: An electronic component attaching tool suitable for an external shape of a semiconductor device is prepared. The electronic component attaching tool has a function of aligning a position of the semiconductor device to an IC socket. The electronic component attaching tool is mounted on the standard surface that is formed on the IC socket substantially regardless of the external shape of the semiconductor device. The semiconductor device is then aligned and attached to the IC socket by using the electronic component attaching tool, and the electronic component attaching tool is removed from the IC socket. Another electronic component attaching tool suitable for an external shape of another semiconductor device is prepared, and the same procedure as the above is performed to align and attach this semiconductor device to the same type IC socket.
    Type: Grant
    Filed: September 5, 2003
    Date of Patent: August 2, 2005
    Assignee: Fujitsu Limited
    Inventors: Daisuke Koizumi, Shigeyuki Maruyama, Kazuhiro Tashiro, Naoyuki Watanabe