Patents by Inventor Takeshi Maeda

Takeshi Maeda 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).

  • Information storage medium, playback and recording method
    Patent number: 7339875
    Abstract: An information storage medium includes a substrate forming a first groove having a depth, and a second groove adjacent to the first groove and different depth from the first groove; and a recording layer formed on the substrate to record information marks, making optical characteristics of the information marks different for each such that diffracted lights from the plurality of marks orthogonally intersect one another.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: March 4, 2008
    Assignee: Hitachi, Ltd.
    Inventor: Takeshi Maeda
  • Antenna Device and Radio Communication Apparatus
    Publication number: 20080018548
    Abstract: An antenna device has a plane ground conductor plate, and two radiating conductors disposed on the upper side of the plane ground conductor plate in parallel to and adjacently to each other so as to be symmetrical with each other with reference to the center of the plane ground plate. The radiating plates are individually provided with respective feeder ports, and are operated independently from each other. End portions of the radiating conductors may be bent to be substantially perpendicular to the plane ground plate in a direction of achieving a maximum gain, whereby isolation between the feeder ports can be enhanced. With this antenna device, antenna directivity can be secured, a high antenna gain can be obtained, and the going-round of a current from a transmitting unit to a receiving unit can be suppressed favorably.
    Type: Application
    Filed: April 15, 2005
    Publication date: January 24, 2008
    Applicant: Sony Corporation
    Inventor: Takeshi Maeda
  • THREE-DIMENSIONAL RECORDING AND REPRODUCING APPARATUS
    Publication number: 20080012934
    Abstract: A recording medium including a plurality of recording layers, including: an optional first recording layer on which a light spot at a diffraction limit is formed; and a second recording layer on which a mark string pattern is formed, said second recording layer being different from said first recording layer, wherein when said mark string pattern is formed on a light receiving plane, while information of said first recording layer is reproduced, assuming that an optical distance between said first and second recording layers is dm, an optical distance d between optional two recording layers among a plurality of said recording layers is different from said dm.
    Type: Application
    Filed: July 23, 2007
    Publication date: January 17, 2008
    Inventors: Hisataka Sugiyama, Takeshi Maeda, Kiyoshi Matsumoto, Motoyasu Terao, Shigenori Okamine, Tetsuya Nishida, Harukazu Miyamoto
  • Information reproducing apparatus and method
    Publication number: 20070274186
    Abstract: There is provided an optical information recording/reproducing apparatus capable of obtaining a high super-resolution effect using an optical information recording medium in which a super-resolution thin film is formed. An optical information recording medium 1 having a super-resolution layer is irradiated with a laser light in a light emission pattern such that a bias light emission portion that does not cause the super-resolution layer to be in the state of super-resolution and a pulse light emission portion that causes the super-resolution layer to be in the state of super-resolution alternatively appear, and reflected light is detected. A reproduction signal based on the pulse light emission portion and a reproduction signal based on the bias light emission portion are acquired.
    Type: Application
    Filed: August 9, 2006
    Publication date: November 29, 2007
    Inventor: Takeshi Maeda
  • Angular velocity sensor
    Patent number: 7296467
    Abstract: An angular velocity sensor 1 includes support members 10A1, 10A2, 10B1 and 10B2, bonded to two nodal points of a pillar-shaped oscillator, generated on oscillations of the oscillator, in a manner of sandwiching the nodal points from upper and lower sides of the oscillator. The support members simultaneously serve for mechanically supporting and providing for electrical connection of the oscillator. Upper support members 10A1, 10A2 and lower support members 10B1 and 10B2 for the nodal points include bent parts, the bent parts being bent in the same direction with respect to the longitudinal direction of the oscillator. The upper support members and lower support members also include arms 11 extending at right angles to the up-and-down direction and to the longitudinal direction of the oscillator and connecting portion 13 for the arms and the oscillator.
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: November 20, 2007
    Assignee: Sony Corporation
    Inventors: Toshiyuki Kawamura, Yoshinori Satoh, Toru Matsunaga, Takeshi Maeda, Naoya Sasaki, Kazuhiro Chiba
  • Optical head with lasers and mirrors in a recess formed in a substrate
    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
  • Multi-layered optical recording medium, information recording method, and information reproduction method
    Publication number: 20070247999
    Abstract: High-speed and high-density recording of a layer-selected optical disc are enabled with a small number of electrodes. A plurality of recording films that are independently selectable are disposed between a pair of electrodes 3 and 8. The recording films are controlled individually in terms of a threshold of voltage required for coloration and electric characteristics. A desired layer can be selected by changing the voltage applied between the pair of electrodes.
    Type: Application
    Filed: August 31, 2006
    Publication date: October 25, 2007
    Inventors: Masaki Mukoh, Takeshi Maeda, Akemi Hirotsune
  • Three-dimensional recording and reproducing apparatus
    Patent number: 7286153
    Abstract: In a three-dimensional recording and reproducing apparatus having a recording medium including a plurality of recording layers stacked on a substrate and an optical system for converging a light irradiated from the substrate side on each of the plurality of recording layers to three-dimensionally record and reproduce information, the following equation is satisfied: ?/4?(1/8NB)(1/NB2?1)NAF4?d where ?: Wavelength of the light; NB: Refractivity of the substrate 3; NAF: Numerical aperture of a focus lens 8 for converging a light; ?d: Positional range in the optical axis direction in which exists a recording layer on which the light is to be converged. A light spot is focused on each layer of the multi-layer structured disc to record and reproduce highly reliable data in a high density.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: October 23, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Hisataka Sugiyama, Takeshi Maeda, Kiyoshi Matsumoto, Motoyasu Terao, Shigenori Okamine, Tetsuya Nishida, Harukazu Miyamoto
  • Optical disk apparatus using mechanism for controlling spherical aberration
    Patent number: 7283439
    Abstract: In the past there has been a problem that on a detection surface the influence of interference causes a defocusing signal to degrade, narrowing the range in which spherical aberration can be stably detected. Accordingly, a diffraction grating is used to focus the inner and outer sides of luminous flux on separate optical detectors before the optical flux is focused on an optical detector and defocusing signals are independently calculated to find the difference therebetween, thereby providing a spherical aberration signal. This makes it possible to detect spherical aberration signals more stably.
    Type: Grant
    Filed: November 10, 2005
    Date of Patent: October 16, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Takeshi Shimano, Takeshi Maeda, Hirofumi Sukeda
  • Information Recording Method, Information Recording Medium And Information Recording Apparatus
    Publication number: 20070237049
    Abstract: An information recording method using a recording medium includes forming a plurality of recording pulses in accordance with both a reference waveform having been stored in the recording medium and data regarding a shifting value relying on material of the recording medium also having been stored in the recording medium in a table manner, and recording information included in the plurality of recording pulses to the recording medium. The recording information is arranged to be stored according to the material of the recording medium.
    Type: Application
    Filed: June 14, 2007
    Publication date: October 11, 2007
    Inventors: Takeshi Maeda, Hirofumi Sukeda, Hiroyuki Minemura, Hidehiko Kando, Makoto Miyamoto
  • INFORMATION RECORDING MEDIUM AND INFORMATION REPRODUCTION METHOD
    Publication number: 20070230319
    Abstract: An information recording medium having a plurality of tracks, wherein the respective tracks at least include: a plurality of segments, and having redundancy of identical information being maintained in at least two of the segments of the same track.
    Type: Application
    Filed: June 7, 2007
    Publication date: October 4, 2007
    Inventors: HARUKAZU MIYAMOTO, Hiromi Kudo, Takeshi Maeda
  • Information recording and reproducing apparatus, and information recording method
    Publication number: 20070206474
    Abstract: Interlayer crosstalk from a layer (non-readout layer) other than a readout layer, which poses a problem for a next-generation multi-layer optical disk, is reduced. A plurality (t) of tables showing a correspondence between user data and combinations of length, position, and total area of one or a plurality of marks in the user data are used. The possible range of the total mark area is varied depending on the tables. The tables containing user data and combinations of the length, position, and total area of the marks are switched by determining between what values in a number (t-l) of combinations of thresholds of mark areas the total area value of the marks contained in the predetermined number of past data cells (m) falls. The amount of disturbance in mark area is reduced by restricting the range of the area of a subsequent mark that is to appear.
    Type: Application
    Filed: June 30, 2006
    Publication date: September 6, 2007
    Inventors: Masaharu Kondou, Takeshi Maeda
  • Information recording method and information recording apparatus
    Patent number: 7263053
    Abstract: An information recording method and information recording apparatus is capable of resolving the trade-off relation between recording density and transmittance, wherein either the reproduction (playback) signal quality or the recording sensitivity is lowered. For this purpose, a voltage is applied by way of ball bearings or slip rings to a specified layer of a medium having multiple layers. The light transmittance of the recording layer is changed by application of this voltage. The tradeoff relationship between recording density and transmittance is eliminated thereby, and the recording density and transmittance levels are both improved, so as to enhance the recording reliability.
    Type: Grant
    Filed: April 6, 2004
    Date of Patent: August 28, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Motoyasu Terao, Katsuhiko Yamaguchi, Tadao Ino, Kyoko Kojima, Harukazu Miyamoto, Takeshi Maeda, Yuko Tsuchiya
  • OPTICAL INFORMATION RECORDING AND REPRODUCING APPARATUS
    Publication number: 20070177476
    Abstract: An optical information recording and reproducing apparatus comprises an optical disk having a reflection layer, an optical information recording layer, a super resolution layer and a protection layer on the recording surface of a substrate, a laser emission control unit for emitting the laser light to record and reproduce the optical information and changing the pulse-like emission pattern, a pickup for radiating by focusing the laser light and receiving the reflected light, a spindle and a spindle motor for supporting and rotationally driving the optical disk, and a reproduction signal processing unit for arithmetically processing the received signal.
    Type: Application
    Filed: January 17, 2007
    Publication date: August 2, 2007
    Inventors: Hiroki Yamamoto, Takeshi Maeda
  • Liquid crystal display control device
    Publication number: 20070164968
    Abstract: There is provided a liquid crystal display control device which can display pictures in a magnification mode by using only a memory having low-speed access and a low storage capacity. When a video signal has intermediate resolution or less, the enlargement processing is performed by a frame memory, a line memory and an enlargement processing control circuit. If the input operation and the output operation to and from the frame memory are synchronized with each other, it is sufficient for the frame memory to have a storage capacity of two lines. When the video signal has the same high resolution as a liquid crystal display panel, the video signal is output through a gate circuit to a display timing generating circuit, and it is displayed in a through mode. In this case, no processing is performed by the frame memory or the like.
    Type: Application
    Filed: March 5, 2007
    Publication date: July 19, 2007
    Inventors: Tsutomu Furuhashi, Takeshi Maeda, Atsuhiro Higa, Hisayuki Ohhara, Hiroshi Kurihara, Naruhiko Kasai
  • Double-row self-aligning roller bearing and device for supporting wind turbine generator main shaft
    Publication number: 20070127858
    Abstract: A double-row self-aligning roller bearing includes left and right rows of rollers 4 and 5, arranged between an inner race 2 and an outer race 3. A raceway surface 3a of the outer race 3 represents a spherical shape and the rollers 4 and 5 have an outer peripheral surface following the shape of the raceway surface 3a of the outer race 3. The rollers 4 and 5 of the left and right roller rows have respective lengths L1 and L2 different from each other. Also, the left and right roller rows have respective contact angles ?1 and ?2 different from each other.
    Type: Application
    Filed: November 16, 2004
    Publication date: June 7, 2007
    Inventors: Naoki Nakagawa, Masaharu Hori, Takeshi Maeda, Souichi Yagi, Mitsuo Sasabe, Nobuyuki Mori
  • Magneto-optical data recording/reproducing method
    Patent number: 7227818
    Abstract: A method of recording data into a recording medium by forming a recording region which is physically different from the nonrecorded portions is disclosed. The optical data recording/reproducing method includes a first trial writing operation in which trial writing data are recorded into the recording medium while changing the recording power conditions, the recorded trial writing data are reproduced, and the reproduced trial writing data are evaluated to set an optimum recording power. The method also includes a second trial writing operation in which trial writing data are recorded into the recording medium while changing the servo conditions, the recorded trial writing data are reproduced, and the reproduced trial writing data are evaluated to set optimum servo conditions.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: June 5, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Tsuyoshi Toda, Takeshi Maeda, Fumio Kugiya, Hiroshi Ide, Hiroyuki Tsuchinaga, Fumiyoshi Kirino, Toshimitsu Kaku, Kazuo Shigematsu
  • AGENT SYSTEM
    Publication number: 20070088777
    Abstract: In an agent system having a plurality of agents each of which executes predetermined processing while moving through a plurality of nodes connected to an information network, the plurality of nodes respectively have a plurality of agent platforms which receive and execute the agents, one of the agent platform and the node has synchronization means, and when the plurality of agents which are running on the same node should synchronously execute operation, the plurality of agents on the same node execute processing synchronously by sending a synchronization request message to the synchronization means.
    Type: Application
    Filed: November 14, 2006
    Publication date: April 19, 2007
    Inventors: Takeshi MAEDA, Shigeki Katayama, Takahiro Hatanaka, Setsuo Tamura, Manabu Shimoo, Yoshihiro Koizumi, Tatsuji Tanaka, Takaya Shono, Katsuhiko Sekiguchi, Koichi Sawai
  • Liquid crystal display control device
    Patent number: 7202848
    Abstract: There is provided a liquid crystal display control device which can display pictures in a magnification mode by using only a memory having low-speed access and a low storage capacity. When a video signal has intermediate resolution or less, the enlargement processing is performed by a frame memory, a line memory and an enlargement processing control circuit. If the input operation and the output operation to and from the frame memory are synchronized with each other, it is sufficient for the frame memory to have a storage capacity of two lines. When the video signal has the same high resolution as a liquid crystal display panel, the video signal is output through a gate circuit to a display timing generating circuit, and it is displayed in a through mode. In this case, no processing is performed by the frame memory or the like.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: April 10, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Furuhashi, Takeshi Maeda, Atsuhiro Higa, Hisayuki Ohhara, Hiroshi Kurihara, Naruhiko Kasai
  • Imformation recording medium and method for manufacturing the same
    Publication number: 20070058518
    Abstract: In an optical disk in which a recording layer is selected by applying voltages, a different address pit is formed in each recording layer. To this end, a plurality of recording layers are formed in a way that the plurality of recording layers follow a concavo-convex shape formed in a substrate, and thus the plurality of recording layers keep the concavo-convex shape even after the formation; mutually different address marks are add-on written, as a part of the address information, respectively to recording layer so that the address and track information can be confirmed in each layer.
    Type: Application
    Filed: August 9, 2006
    Publication date: March 15, 2007
    Inventors: Akemi Hirotsune, Motoyasu Terao, Takeshi Maeda, Masaki Mukoh, Toshimichi Shintani