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).

  • Patent number: 7489610
    Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: February 10, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Shinji Fujita, Takeshi Maeda, Manabu Shiozawa, Takahiro Kurokawa
  • Patent number: 7486603
    Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: February 3, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Shinji Fujita, Takeshi Maeda, Manabu Shiozawa, Takahiro Kurokawa
  • Publication number: 20090010132
    Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.
    Type: Application
    Filed: July 31, 2008
    Publication date: January 8, 2009
    Applicant: Hitachi, Ltd.
    Inventors: Shinji FUJITA, Takeshi MAEDA, Manabu SHIOZAWA, Takahiro KUROKAWA
  • Patent number: 7471605
    Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: December 30, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Shinji Fujita, Takeshi Maeda, Manabu Shiozawa, Takahiro Kurokawa
  • Publication number: 20080291796
    Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.
    Type: Application
    Filed: July 31, 2008
    Publication date: November 27, 2008
    Applicant: Hitachi, Ltd.
    Inventors: Shinji FUJITA, Takeshi Maeda, Manabu Shiozawa, Takahiro Kurokawa
  • Publication number: 20080291795
    Abstract: An optical disk recording method includes the steps of: providing a multi-pulse chain from a recording wave; independently changing the pulse rise timing and pulse fall timing (pulse width) of the first pulse in the multi-pulse chain in accordance with a preceding space length and a recording mark length; changing the pulse rise timing and pulse fall timing (pulse width) in accordance with a following space length and the recording mark length in a predetermined timing or in independence; and in relation to the smallest mark recorded by irradiation with mono pulse, changing the rise timing in accordance with the preceding space length and the recording mark length and the fall timing (pulse width) in accordance with the following space length and recording mark length, compensating various optical disks different in recording material without change of the fundamental waveform.
    Type: Application
    Filed: July 31, 2008
    Publication date: November 27, 2008
    Applicant: Hitachi, Ltd.
    Inventors: Shinji FUJITA, Takeshi Maeda, Manabu Shiozawa, Takahiro Kurokawa
  • Publication number: 20080273446
    Abstract: Conventionally, as in the case of switching between a DVD-R and a DVD-RAM, when the method of record mark arrangement in a track is changed, the physical format of the disk is also changed. This makes it difficult to ensure compatibility between pieces of data recorded by a plurality of different methods of record mark arrangement. According to the present invention, sector address data and block address data are recorded in each sector by using wobbling or deformation of a recording groove. Then, depending on which address is used, sector data structure is modified, thereby making it possible to select an address data detection and a data structure on a disk in a single physical format depending on the purpose.
    Type: Application
    Filed: May 29, 2008
    Publication date: November 6, 2008
    Inventors: Hidehiko Kando, Harukazu Miyamoto, Takeshi Maeda
  • Patent number: 7432897
    Abstract: A liquid crystal display device for displaying video data having a detection circuit for detecting a luminance distribution based on video data which is inputted, the luminance distribution being indicative of generation frequency of gradations in each of divided region which includes a plurality of gradations. The display device includes a determination circuit for determining at least one of a plurality of divided regions of higher generation frequency of gradation than that of other divided regions based on the luminance distribution, a correction circuit for correcting the video data so as to make a luminance characteristic of the at least one of the plurality of divided regions of higher generation frequency of gradation more abrupt than a luminance characteristic of the other divided regions, and a liquid crystal display panel for displaying the corrected video data. A width of the divided region is changeable.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: October 7, 2008
    Assignees: Hitachi, Ltd., Hitachi Video and Information System, Inc., Hitachi Microsoftware Systems, Inc.
    Inventors: Shigeyuki Nishitani, Takeshi Maeda, Kazuyoshi Kawabe, Hiroshi Kurihara, Tetsuo Takagi, Toshiaki Ohashi
  • Publication number: 20080219109
    Abstract: Provided is a recording and retrieval apparatus for a multi-layer optical disk. A multi-layer optical disk in which a plurality of recording layers and a single servo layer are combined to form a set is used. A spot for the servo layer and a spot for the recording layers are turned on in a time-sharing manner. Servo signal detection areas are formed discretely in the servo layer. The servo signal detection areas and data recording areas are provided so as not to overlap each other when viewed from the spot incident side. Thus, separation of data from each of the layers can be done by even a single photodetector without interference.
    Type: Application
    Filed: July 19, 2007
    Publication date: September 11, 2008
    Inventors: Takeshi Maeda, Takeshi Shimano, Akemi Hirotsune, Harukazu Miyamoto
  • Publication number: 20080202447
    Abstract: An engine-driven generator is provided that is formed by supporting an engine (3) and a generator (4) on a frame (2), wherein the frame (2) is formed as an open periphery framework type, within this frame (2) a duct member (31) is disposed around the outer periphery of the engine (3) and the generator (4), the duct member (31) defining a series of cooling air passages (32) between itself and the engine (3) and generator (4), a cooling fan (26) is provided in the cooling air passage (32), the cooling fan (26) being driven by the engine (3), an intake box (34) having an intake opening (38) at an outer end thereof and housing an electrical component (53, 55) is connected to the upstream end of the duct member (31), and an exhaust box (68) having an exhaust opening (73) at an outer end thereof and housing an exhaust muffler (74) of the engine (3) is connected to the other end of the duct member (31). A compact engine-driven generator that enables running noise to be reduced can thereby be provided.
    Type: Application
    Filed: July 8, 2004
    Publication date: August 28, 2008
    Inventors: Toshifumi Kochi, Tadafumi Hirose, Ryuji Tsuru, Shouhei Kasagi, Yuji Shimada, Takeshi Maeda
  • Patent number: 7417942
    Abstract: There are provided parts where respective addresses of grooves on both sides of a land are identical to each other, and selection marks indicating validity of the parts are disposed. The selection marks determines the validity by taking advantage of the fact that there occurs a difference in wobble waveform in the land between a case of wobble data of the grooves on both sides of the land are identical and a case of the wobble data differ from each other. In this case, the wobble address method having an advantageous format efficiency can be used in combination with land/groove recording capable of narrowing down tracks, so that a reproduction method using a large capacity optical disc capable of high-density recording can be implemented.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: August 26, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Harukazu Miyamoto, Hiromi Kudo, Takeshi Maeda
  • Patent number: 7404426
    Abstract: A hybrid cord 1 for rubber reinforcement comprises a strand 2 having higher elastic modulus, made of PBO fiber or the like, which is disposed at the center of the cord, and strands 3 having lower elastic modulus, made of glass fiber or the like, which are disposed therearound. The hybrid cord has enough strength and is excellent in flexural fatigue resistance, adhesion property relative to rubber, and dimensional stability. A rubber product employs this hybrid cord 1 for rubber reinforcement.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: July 29, 2008
    Assignee: Nippon Sheet Glass Co., Ltd.
    Inventors: Mitsuharu Akiyama, Takeshi Maeda, Yukinari Okuyama
  • Publication number: 20080159100
    Abstract: An information recording medium including a plurality of layers for recording or reproduction of information by irradiation of light and a tracking error signal for determining a layer number being recorded in each of the plurality of layers. A modulation of the tracking error signal is different in each of the plurality of layers.
    Type: Application
    Filed: March 11, 2008
    Publication date: July 3, 2008
    Inventors: Akemi HIROTSUNE, Harukazu Miyamoto, Takeshi Maeda
  • Patent number: 7391710
    Abstract: A method for determining layers in a recording medium having a plurality of layers for the recording and reproduction of information using light irradiation. Each of the plurality of layers includes an emboss portion and a wobble region having wobbles of a predetermined frequency. Layer determination is carried out based on the ratio of the amplitude of a wobble signal obtained from the wobble region to the amplitude of a reproduction signal from the emboss portion.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: June 24, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Akemi Hirotsune, Harukazu Miyamoto, Takeshi Maeda
  • Patent number: 7385909
    Abstract: Conventionally, as in the case of switching between a DVD-R and a DVD-RAM, when the method of record mark arrangement in a track is changed, the physical format of the disk is also changed. This makes it difficult to ensure compatibility between pieces of data recorded by a plurality of different methods of record mark arrangement. According to the present invention, sector address data and block address data are recorded in each sector by using wobbling or deformation of a recording groove. Then, depending on which address is used, sector data structure is modified, thereby making it possible to select an address data detection and a structure on a disk in a single physical format depending on the purpose.
    Type: Grant
    Filed: January 4, 2006
    Date of Patent: June 10, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Hidehiko Kando, Harukazu Miyamoto, Takeshi Maeda
  • Patent number: 7359302
    Abstract: In a method of recording information by varying the front- and rear-edge positions of a mark by integer multiples of a specific interval, the recording density is increased without narrowing the intervals of edge position variation and without being influenced by the detection dynamic range. A data cell is divided at specific intervals ?, and the front- and rear-edge positions of the mark are disposed at any desired positions at specific intervals ?. Thus the mark length and the number of positions the mark can take can be increased, so that the recording density can be increased with the same margin as that of the prior art.
    Type: Grant
    Filed: January 22, 2003
    Date of Patent: April 15, 2008
    Assignee: Hitachi, Ltd.
    Inventor: Takeshi Maeda
  • Patent number: 7352675
    Abstract: An information recording method using an optical recording medium including the steps of forming a plurality of recording pulses to irradiate the optical recording medium and recording information to the optical recording medium by irradiating the recording pulses on the optical recording medium. A leading edge of a first recording pulse of the recording pulses shifts at a shifting value, and the shifting value is determined by a combination of a length of M(n) of a mark being currently written and a length s(n?1) of a space precedent to the mark.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: April 1, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Takeshi Maeda, Hirofumi Sukeda, Hiroyuki Minemura, Hidehiko Kando, Makoto Miyamoto
  • Patent number: 7349319
    Abstract: An information recording apparatus includes a multilayer information recording medium having a first layer containing an electro-chromic material, an electrode layer applying a voltage to the first layer to color the first layer, a second layer containing an electro-chromic material, a unit for applying the voltage to the first layer, a first optical irradiating unit for irradiating a first optical spot onto the first layer, and a second optical irradiating unit for irradiating a second optical spot onto the second layer after irradiating the first optical spot onto the first layer.
    Type: Grant
    Filed: January 26, 2004
    Date of Patent: March 25, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Motoyasu Terao, Kyoko Kojima, Hiroyuki Minemura, Takeshi Maeda, Takeshi Shimano
  • Patent number: 7349318
    Abstract: An information recording apparatus using an optical recording medium includes a light source to irradiate a light beam to the optical recording medium and a pulse former for forming a plurality of recording pulses of the light beam. A leading edge of a first recording pulse of the recording pulses shifts at a shifting value, and the shifting value is determined by a combination of a length of M(n) of a mark being currently written and a length s(n?1) of a space precedent to the mark.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: March 25, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Takeshi Maeda, Hirofumi Sukeda, Hiroyuki Minemura, Hidehiko Kando, Makoto Miyamoto
  • Patent number: 7349317
    Abstract: An information recording method using an optical recording medium includes the steps of forming a plurality of recording pulses to irradiate the optical recording medium and recording information to the optical recording medium by irradiating the recording pulses on the optical recording medium. At least a leading edge of a first recording pulse and a trailing edge of a last recording pulse of the recording pulses shift at a shifting value, wherein the shifting value is determined by combinations of a length of M(n) of a mark being currently written and at least one of a length s(n?1) of a space precedent to the mark and a length s(n+1) of a space subsequent to the mark.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: March 25, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Takeshi Maeda, Hirofumi Sukeda, Hiroyuki Minemura, Hidehiko Kando, Makoto Miyamoto