Patents by Inventor Takashi Kikukawa

Takashi Kikukawa 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: 10799863
    Abstract: A chemical sensor that enables high detection accuracy. A chemical sensor includes a substrate, a magnetoresistance-effect element disposed over the substrate, a first film disposed over the magnetoresistance-effect element, and a second film disposed in a region in the vicinity of the magnetoresistance-effect element or over a region in the vicinity of the magnetoresistance-effect element, wherein the second film has higher solubility in a specific liquid than the first film.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: October 13, 2020
    Assignee: TDK CORPORATION
    Inventors: Sachio Tsuboike, Susumu Haratani, Sumiko Kitagawa, Takashi Kikukawa, Haruki Yuga
  • Publication number: 20200271963
    Abstract: An optical modulator is provided with a substrate, first and second optical waveguides each formed of a ridge-shaped electro-optic material film and disposed so as to be mutually adjacent on the substrate, a buffer layer covering upper surfaces of the first and second optical waveguides, first and second signal electrodes provided above the buffer layer so as to be opposed respectively to the first and second optical waveguides, and a dielectric layer covering at least one of a part of an exposed surface of the first signal electrode and a part of an exposed surface of the second signal electrode, and a part of an upper surface of the buffer layer. Differential signals are applied to the first and second signal electrodes.
    Type: Application
    Filed: February 24, 2020
    Publication date: August 27, 2020
    Inventors: Shinji Iwatsuka, Kenji Endou, Hiroki Hara, Toshinori Matsuura, Takashi Kikukawa, Yasuhiro Ohmori, Masaharu Doi, Shintaro Takeuchi, Takehito Tanaka, Yoshinobu Kubota
  • Publication number: 20200272020
    Abstract: An optical modulator is provided with a ridge-shaped optical waveguide formed of a dielectric thin film having electro-optic effect, a buffer layer covering the optical waveguide, a signal electrode formed on the buffer layer so as to be opposed to the optical waveguide through the buffer layer; a ground electrode formed on the buffer layer together with the signal electrode, and a dielectric film having a higher dielectric constant than air and covering at least a part of exposed surfaces of the signal electrode and ground electrode and exposed surfaces of the buffer layer.
    Type: Application
    Filed: February 24, 2020
    Publication date: August 27, 2020
    Inventors: Yasuhiro OHMORI, Masaharu DOI, Shintaro TAKEUCHI, Takehito TANAKA, Yoshinobu KUBOTA, Shinji IWATSUKA, Kenji ENDOU, Hiroki HARA, Toshinori MATSUURA, Takashi KIKUKAWA
  • Publication number: 20200272021
    Abstract: An electro-optic device is provided with a Mach-Zehnder optical waveguide including at least one linear section and at least one curved section and a differential RF signal electrode provided along the Mach-Zehnder optical waveguide. Optical input/output ports of the Mach-Zehnder optical waveguide are provided at one end side in a first direction in which the linear section extends. The differential RF signal electrode is provided in both the linear and curved sections.
    Type: Application
    Filed: February 24, 2020
    Publication date: August 27, 2020
    Applicant: FUJITSU OPTICAL COMPONENTS LIMITED
    Inventors: Hiroki HARA, Shinji IWATSUKA, Takashi KIKUKAWA, Toshinori MATSUURA, Yasuhiro OHMORI, Masaharu DOI, Shintaro TAKEUCHI, Yoshinobu KUBOTA
  • Publication number: 20200049888
    Abstract: A first disclosure is an optical fiber member equipped with two holding members that hold an optical fiber such that an end surface of the optical fiber is located on one end and a curving portion having a coat of the optical fiber is curved to be extended at another end; the holding members are provided with holding flat portions that sandwich an end portion of the optical fiber where the coat is removed such that the end surface of the optical fiber is located on the one end; at least any of the holding flat portions has an aligning groove to fix a position of the end portion of the optical fiber; the holding member is provided with a curved surface at a position adjacent to the curving portion in the extending direction Dl; and the two holding members are equal in thermal expansion coefficient.
    Type: Application
    Filed: February 20, 2018
    Publication date: February 13, 2020
    Inventors: Hiroki HARA, Masahiro SHINKAI, Takashi KIKUKAWA, Masami SASAKI, Ryohei FUKUZAKI, Motohiro NAKAHARA, Tetsuo MIYA, Shuji TACHI, Koichi ARISHIMA
  • Publication number: 20190224671
    Abstract: A biosensor includes a substrate having a surface in which a first region and a second region disposed adjacent to the first region are formed; a magnetoresistance effect element that is disposed on at least the first region and is configured such that a resistance value detected according to an input magnetic field varies; a protective film that is disposed on both the first region and the second region and covers a surface of the magnetoresistance effect element, and is disposed on the top part of the second region and contains an affinity substance that allows recognition of the biomolecules on the outer surface only on the second region; and an adsorption prevention film that is disposed on at least the top part of the first region and is substantially free of the affinity substance, wherein the protective film and the adsorption prevention film are made of different materials.
    Type: Application
    Filed: March 24, 2017
    Publication date: July 25, 2019
    Applicant: TDK CORPORATION
    Inventors: Susumu HARATANI, Sachio TSUBOIKE, Sumiko KITAGAWA, Takashi KIKUKAWA, Haruki YUGA
  • Publication number: 20190154676
    Abstract: A detection system includes a detection device including a space, defined by a wall surface, into which a liquid containing a biomolecular label and a liquid containing magnetic beads are introduced and a magnetic sensor having a surface forming a portion of the wall surface, wherein at least some of the magnetic beads bind to the biomolecular label immobilized on the surface of the magnetic sensor or to a molecule near the biomolecular label immobilized on the surface of the magnetic sensor; and a first magnetic-field applying mechanism that applies a magnetic field in a direction in which the magnetic beads are moved away from the surface of the magnetic sensor.
    Type: Application
    Filed: July 22, 2016
    Publication date: May 23, 2019
    Applicant: TDK CORPORATION
    Inventors: Haruki YUGA, Seigo ZAIMA, Takashi KIKUKAWA, Sachio TSUBOIKE
  • Publication number: 20190128882
    Abstract: What provided is a biosensor including: a substrate having a surface with first and second regions adjacent to each other; a magnetoresistance effect element that is disposed at least on the first region and is configured for a detected resistance value to be changed based on an input magnetic field; a protective film that is disposed on both the first region and the second region, covers a surface of the magnetoresistance effect element, is disposed on the top part of the first region and contains an affinity substance capable of recognizing the biomolecule on the outer surface of the first region exclusively; and an adsorption prevention film that is disposed on at least the top part of the second region and is substantially free of the affinity substance, wherein the protective film and the adsorption prevention film are made of different materials.
    Type: Application
    Filed: March 24, 2017
    Publication date: May 2, 2019
    Applicant: TDK CORPORATION
    Inventors: Susumu HARATANI, Sachio TSUBOIKE, Sumiko KITAGAWA, Takashi KIKUKAWA, Haruki YUGA
  • Publication number: 20190120794
    Abstract: A chemical sensor that enables high detection accuracy that includes a soft-magnetic-material film, a magnetoresistance-effect element, a first film disposed over the soft-magnetic-material film, and a second film disposed over the magnetoresistance-effect element, wherein, when viewed from a direction perpendicular to the film surface of the soft-magnetic-material film, the soft-magnetic-material film is disposed at least partially so as not to overlap the magnetoresistance-effect element; when viewed from the direction perpendicular to the film surface of the soft-magnetic-material film, the magnetoresistance-effect element is disposed at least partially so as not to overlap the soft-magnetic-material film; and the second film has higher solubility in a specific liquid than the first film.
    Type: Application
    Filed: March 24, 2017
    Publication date: April 25, 2019
    Applicant: TDK Corporation
    Inventors: Sachio TSUBOIKE, Susumu HARATANI, Sumiko KITAGAWA, Takashi KIKUKAWA, Haruki YUGA
  • Publication number: 20190113479
    Abstract: To provide a chemical sensor that enables high detection accuracy. A chemical sensor includes a substrate, two or more magnetoresistance-effect elements disposed side by side in a substrate in-plane direction over the substrate, a first film disposed over a region between the magnetoresistance-effect elements adjacent to each other, and a second film disposed over the magnetoresistance-effect elements, wherein the second film has higher solubility in a specific liquid than the first film.
    Type: Application
    Filed: March 24, 2017
    Publication date: April 18, 2019
    Applicant: TDK CORPORATION
    Inventors: Sachio TSUBOIKE, Susumu HARATANI, Sumiko KITAGAWA, Takashi KIKUKAWA, Haruki YUGA
  • Publication number: 20190107512
    Abstract: A chemical sensor that enables high detection accuracy. A chemical sensor includes a substrate, a magnetoresistance-effect element disposed over the substrate, a first film disposed over the magnetoresistance-effect element, and a second film disposed in a region in the vicinity of the magnetoresistance-effect element or over a region in the vicinity of the magnetoresistance-effect element, wherein the second film has higher solubility in a specific liquid than the first film.
    Type: Application
    Filed: March 24, 2017
    Publication date: April 11, 2019
    Applicant: TDK CORPORATION
    Inventors: Sachio TSUBOIKE, Susumu HARATANI, Sumiko KITAGAWA, Takashi KIKUKAWA, Haruki YUGA
  • Publication number: 20190064046
    Abstract: What provided is a biosensor including: a substrate having a surface with first and second regions adjacent each other; a magnetoresistance effect element disposed on the first region; a soft magnetic thin film on the second region; a protective film disposed on both the first region and the second region, covering a surface of the soft magnetic thin film, and disposed on the top part of the second region and contains an affinity substance recognizing the biomolecule on the outer surface of the second region exclusively; and an MR cover film disposed on at least the top part of the first region, disposed on the protective film above the magnetoresistance effect element, and being free of the affinity substance, wherein the soft magnetic thin film transmits an in-plane component of a stray magnetic field of magnetic beads to the magnetoresistance effect element.
    Type: Application
    Filed: March 24, 2017
    Publication date: February 28, 2019
    Applicant: TDK CORPORATION
    Inventors: Susumu HARATANI, Sachio TSUBOIKE, Sumiko KITAGAWA, Takashi KIKUKAWA, Haruki YUGA
  • Patent number: 9007883
    Abstract: An optical recording medium includes a recording and reading layer that is previously staked or formed afterword and has no concavo-convex pattern for tracking control, and a servo layer in which a concavo-convex pattern or a groove for tracking control is formed. Information can be recorded in the recording and reading layer while tracking is performed using the servo layer.
    Type: Grant
    Filed: December 11, 2013
    Date of Patent: April 14, 2015
    Assignee: TDK Corporation
    Inventors: Motohiro Inoue, Tomoki Ushida, Atsuko Kosuda, Takashi Kikukawa
  • Patent number: 8830803
    Abstract: An optical drive apparatus that reproduces an optical disk having a land and a groove, the optical drive apparatus including a first tracking-error-signal generating unit that generates a first tracking error signal by using a DPD method, a second tracking-error-signal generating unit that generates a second tracking error signal by using a DPP method, a tracking servo unit that controls the optical system, and a determining unit that determines that an irradiation point of an optical beam is in a non-recorded area. The tracking servo unit switches over to a control based on the second tracking error signal in response to a result of determination by the determining unit during performing a control based on the first tracking error signal.
    Type: Grant
    Filed: August 10, 2010
    Date of Patent: September 9, 2014
    Assignee: TDK Corporation
    Inventors: Tetsuya Nishiyama, Takashi Kikukawa
  • Publication number: 20140169147
    Abstract: An optical recording medium includes a recording and reading layer that is previously staked or formed afterword and has no concavo-convex pattern for tracking control, and a servo layer in which a concavo-convex pattern or a groove for tracking control is formed. Information can be recorded in the recording and reading layer while tracking is performed using the servo layer.
    Type: Application
    Filed: December 11, 2013
    Publication date: June 19, 2014
    Inventors: Motohiro INOUE, Tomoki USHIDA, Atsuko KOSUDA, Takashi KIKUKAWA
  • Patent number: 8649250
    Abstract: A series of optical recording media is provided to reduce a burden on an optical pickup by introducing a standardized idea among a plurality of optical recording media. In the series of optical recording media, optical recording media are of a plurality of types, each optical recording medium including a plurality of planar recording and reading layers with no projections and depressions for tracking control, and a servo layer with projections and depressions for tracking control. The plurality of optical recording media have different numbers of stacked recording and reading layers, and the positions of the servo layers with respect to the corresponding light incident surfaces are standardized among the plurality of optical recording media.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: February 11, 2014
    Assignee: TDK Corporation
    Inventors: Hideki Hirata, Takashi Kikukawa, Atsuko Kosuda, Motohiro Inoue
  • Patent number: 8630156
    Abstract: An optical recording medium includes a recording and reading layer that is previously staked or formed afterward and has no concavo-convex pattern for tracking control, and a servo layer in which a concavo-convex pattern or a groove for tracking control is formed. Information can be recorded in the recording and reading layer while tracking is performed using the servo layer.
    Type: Grant
    Filed: February 3, 2012
    Date of Patent: January 14, 2014
    Assignee: TDK Corporation
    Inventors: Motohiro Inoue, Tomoki Ushida, Atsuko Kosuda, Takashi Kikukawa
  • Patent number: 8588045
    Abstract: Information is recorded on a multi-layered optical recording medium by irradiating it with a laser beam. The recording medium can form a first information recording layer that is the farthest from a light incident surface, a second information recording layer that is the second farthest from the light incident surface, and at least one third information recording layer that is located closer to the light incident surface than the second information recording layer is. At this time, if all the information recording layers other than the first information recording layer are either blank or have been completely recorded, then information is recorded on the first information recording layer. This allows for stabilizing the energy of a recording laser beam during recording and thereby providing improved recording quality.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: November 19, 2013
    Assignee: TDK Corporation
    Inventors: Takashi Kikukawa, Koji Mishima
  • Patent number: 8582415
    Abstract: An object of the present invention is to increase the number of stacked layers in a multilayer optical recording medium while simplifying the design of the multilayer optical recording medium is provided a multilayer optical recording medium including at least four recording and reading layers from which information can be reproduced by light irradiation, the layers stacked through intermediate layers. The multilayer optical recording medium includes a plurality of recording and reading layers that are continuous in order of stacking and includes at least one recording and reading layer group in which reflectance in a stacked state decreases from a near side of a light incident surface to a far side. A single-layer reflectance of the nearest recording and reading layer is set to 0.2% or more and less than 2.0%, and a light transmittance improvement process is applied to the light incident surface.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: November 12, 2013
    Assignee: TDK Corporation
    Inventors: Atsuko Kosuda, Takashi Kikukawa, Tomoki Ushida, Motohiro Inoue
  • Patent number: 8520481
    Abstract: In a multilayer optical recording medium, it is an object to suppress generation of crosstalk while reducing an interlayer distance of recording and reading layers. In an optical recording medium including three or more recording and reading layers, a first distance, and a second distance greater than the first distance by 3 ?m or more are alternately defined as interlayer distances of recording and reading layers.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: August 27, 2013
    Assignee: TDK Corporation
    Inventors: Takashi Kikukawa, Atsuko Kosuda, Motohiro Inoue, Hideki Hirata