Patents by Inventor Seiji Imagawa

Seiji Imagawa 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: 20230103773
    Abstract: Provided is a ranging sensor calibration system that can execute a calibration operation during travel at low cost and without adding a special configuration. This ranging sensor calibration system is provided with a plurality of ranging sensors that are installed facing at least a first direction along a direction of travel of a vehicle and a second direction that is an opposite direction to the first direction, and are configured to be able to measure a distance; and a calibration processing unit that configures the plurality of ranging sensors. The calibration processing unit is configured to calibrate the plurality of ranging sensors on the basis of a distance between a plurality of calibration targets disposed near a travel path for the vehicle, a distance between the plurality of ranging sensors, and a distance measured by each of the plurality of ranging sensors.
    Type: Application
    Filed: December 20, 2020
    Publication date: April 6, 2023
    Inventor: Seiji IMAGAWA
  • Patent number: 10877298
    Abstract: A head-mounted display device 1 includes: an image display unit 2 that displays an image; arms 3a and 3b that support the image display unit; and attachment parts 4a and 4b that attach the arms to glasses 100. The arm is formed by a first arm 3a supporting the image display unit and a second arm 3b bonded to the attachment part 4b and includes: a first moving part 5 that can rotate the image display unit 2 with respect to the first arm 3a; and a second moving part 6 that can rotate the first arm 3a to be folded back with respect to the second arm 3b. Directions of a rotation axis of the first moving part 5 and a rotation axis of the second moving part 6 are approximately orthogonal to each other. Accordingly, the head-mounted display device 1 can be stored integrally with the glasses 100.
    Type: Grant
    Filed: June 16, 2015
    Date of Patent: December 29, 2020
    Assignee: MAXELL, LTD.
    Inventor: Seiji Imagawa
  • Patent number: 10613826
    Abstract: Operability of head-mounted display systems is enhanced by incorporating the following: a microphone which receives an utterance input by a person and outputs voice information; a character string generation unit which generates an uttered character string by converting the voice information into a character string; a specific utterance information storage unit which stores specific utterance information that associates at least one program to be started or stopped and/or at least one operating mode to be started or stopped, with specific utterances for starting or stopping each of the programs and/or operating modes; a specific utterance extraction unit which extracts a specific utterance included in the uttered character string with reference to the specific utterance information, and generates an extracted specific utterance signal indicating the extraction result; and a control unit which starts or stops a program or an operating mode with reference to the extracted specific utterance signal.
    Type: Grant
    Filed: December 25, 2014
    Date of Patent: April 7, 2020
    Assignee: MAXELL, LTD.
    Inventor: Seiji Imagawa
  • Publication number: 20180173017
    Abstract: A head-mounted display device 1 includes: an image display unit 2 that displays an image; arms 3a and 3b that support the image display unit; and attachment parts 4a and 4b that attach the arms to glasses 100. The arm is formed by a first arm 3a supporting the image display unit and a second arm 3b bonded to the attachment part 4b and includes: a first moving part 5 that can rotate the image display unit 2 with respect to the first arm 3a; and a second moving part 6 that can rotate the first arm 3a to be folded back with respect to the second arm 3b. Directions of a rotation axis of the first moving part 5 and a rotation axis of the second moving part 6 are approximately orthogonal to each other. Accordingly, the head-mounted display device 1 can be stored integrally with the glasses 100.
    Type: Application
    Filed: June 16, 2015
    Publication date: June 21, 2018
    Inventor: Seiji IMAGAWA
  • Publication number: 20180011687
    Abstract: Operability of head-mounted display systems is enhanced by incorporating the following: a microphone which receives an utterance input by a person and outputs voice information; a character string generation unit which generates an uttered character string by converting the voice information into a character string; a specific utterance information storage unit which stores specific utterance information that associates at least one program to be started or stopped and/or at least one operating mode to be started or stopped, with specific utterances for starting or stopping each of the programs and/or operating modes; a specific utterance extraction unit which extracts a specific utterance included in the uttered character string with reference to the specific utterance information, and generates an extracted specific utterance signal indicating the extraction result; and a control unit which starts or stops a program or an operating mode with reference to the extracted specific utterance signal.
    Type: Application
    Filed: December 25, 2014
    Publication date: January 11, 2018
    Applicant: HITACHI MAXELL, LTD.
    Inventor: Seiji IMAGAWA
  • Patent number: 8634281
    Abstract: The operability of an optical disc device for reading or writing data from/to a disc having a data layer and a servo layer is improved by increasing the resistance to control disturbances. An optical disc device in accordance with the present invention includes an objective lens, a relay lens, a blue-violet laser detector, a red laser detector, an objective lens focus actuator, an objective lens tracking actuator, a relay lens actuator, a pair of focus error signal generating units, a pair of focus control signal generating units, a switching unit for selecting a focus control signal, a pair of tracking error signal generating units, a pair of tracking control signal generating units, a switching unit for selecting a tracking control signal, a focus error conversion unit and a tracking error conversion unit.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: January 21, 2014
    Assignees: Hitachi-LG Data Storage, Inc., Hitachi Consumer Electronics Co., Ltd.
    Inventor: Seiji Imagawa
  • Patent number: 8559285
    Abstract: An optical disc apparatus includes a focus controller including a first digital filter, tracking controller including a second filter, focus actuator driver, tracking actuator driver, defect detector for detecting a defect on an optical disc, and a system controller for controlling the focus controller, the tracking controller and the defect detector. The system controller holds an input and output of at least one of either the focus controller or the tracking controller on the basis of the output of the defect detector, and sets an initial value in a delay memory of the digital filter of the controller held upon awake of the hold state.
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: October 15, 2013
    Assignee: Hitachi Consumer Electronics Co., Ltd.
    Inventor: Seiji Imagawa
  • Patent number: 8547809
    Abstract: There is a need to prevent a possible erroneous detection of an off-track condition during recording to an optical disk. The above need can be addressed by, for example, determining an off-track condition has occurred when a light spot is located at least half-way from the track being recorded toward another track adjacent the track being recorded, and stopping a recording operation. In another example, the above need can be addressed by determining that off-track has occurred based on an output of a first off-track detector which detects that the light spot is off the track based on a wobble signal, an output of a second off-track detector which detects that the light spot is off the track based on a tracking error signal, and an output of a zero-cross detector which detects that the tracking error signal crosses zero based on an output of the tracking error signal.
    Type: Grant
    Filed: June 3, 2009
    Date of Patent: October 1, 2013
    Assignee: Hitachi Consumer Electronics Co., Ltd.
    Inventors: Seiji Imagawa, Yoshinori Ishikawa
  • Publication number: 20130064058
    Abstract: An optical disc apparatus includes a focus controller including a first digital filter, tracking controller including a second filter, focus actuator driver, tracking actuator driver, defect detector for detecting a defect on an optical disc, and a system controller for controlling the focus controller, the tracking controller and the defect detector. The system controller holds an input and output of at least one of either the focus controller or the tracking controller on the basis of the output of the defect detector, and sets an initial value in a delay memory of the digital filter of the controller held upon awake of the hold state.
    Type: Application
    Filed: August 3, 2012
    Publication date: March 14, 2013
    Inventor: Seiji IMAGAWA
  • Patent number: 8325574
    Abstract: An optical disc device capable of preventing a current larger than prescribed in specifications from flowing by measuring amounts of variation in drive signals of the actuator or the spindle motor, and in view of a correlation between those amounts of variation in the drive signals and the amount of current, changing the servo control system characteristics according to measured amounts of variation, and setting a limit to the level of drive signals.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: December 4, 2012
    Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.
    Inventors: Takeyoshi Kataoka, Seiji Imagawa, Munehiro Yonezawa
  • Publication number: 20120230171
    Abstract: The operability of an optical disc device for reading or writing data from/to a disc having a data layer and a servo layer is improved by increasing the resistance to control disturbances. An optical disc device in accordance with the present invention includes an objective lens, a relay lens, a blue-violet laser detector, a red laser detector, an objective lens focus actuator, an objective lens tracking actuator, a relay lens actuator, a pair of focus error signal generating units, a pair of focus control signal generating units, a switching unit for selecting a focus control signal, a pair of tracking error signal generating units, a pair of tracking control signal generating units, a switching unit for selecting a tracking control signal, a focus error conversion unit and a tracking error conversion unit.
    Type: Application
    Filed: March 2, 2012
    Publication date: September 13, 2012
    Inventor: Seiji IMAGAWA
  • Patent number: 8223602
    Abstract: With a high-density optical disc drive, although it is necessary to correct spherical aberrations which depend on a disc substrate thickness error, operation of an aberrations correction element takes time and therefore easy correction according to a disc radius degrades the operability of the apparatus. The present invention comprises an optical pickup unit including an objective lens and an aberrations correction lens, a focus actuator, a tracking actuator, a aberrations correction motor, a seek motor, an aberrations correction lens control module, a radius information detecting module, and a system control module.
    Type: Grant
    Filed: January 11, 2007
    Date of Patent: July 17, 2012
    Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.
    Inventor: Seiji Imagawa
  • Patent number: 7933175
    Abstract: In an optical disc drive that needs an aberration correcting element for correcting spherical aberrations, it takes long time to conduct a processing operation of the aberration correcting element in an interlayer movement of a multilayer disc and a drive initializing operation. In order to eliminate the problem, an optical disc drive using a pickup includes a focus actuator for moving an objective lens in a rotation axis direction of a disc, a tracking actuator for moving the objective lens in a radial direction of the disc, an aberration corrector for correcting aberrations, and a feeder for moving the pickup in the disc radial direction. A control operation of the aberration corrector and a control operation of the feeder are conducted in parallel.
    Type: Grant
    Filed: July 19, 2006
    Date of Patent: April 26, 2011
    Assignees: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.
    Inventor: Seiji Imagawa
  • Publication number: 20090296544
    Abstract: There is a need to prevent a possible erroneous detection of an off-track condition during recording to an optical disk. The above need can be addressed by, for example, determining an off-track condition has occurred when a light spot is located at least half-way from the track being recorded toward another track adjacent the track being recorded, and stopping a recording operation. In another example, the above need can be addressed by determining that off-track has occurred based on an output of a first off-track detector which detects that the light spot is off the track based on a wobble signal, an output of a second off-track detector which detects that the light spot is off the track based on a tracking error signal, and an output of a zero-cross detector which detects that the tracking error signal crosses zero based on an output of the tracking error signal.
    Type: Application
    Filed: June 3, 2009
    Publication date: December 3, 2009
    Inventors: Seiji IMAGAWA, Yoshinori ISHIKAWA
  • Publication number: 20090207708
    Abstract: An optical disc device capable of preventing a current larger than prescribed in specifications from flowing by measuring amounts of variation in drive signals of the actuator or the spindle motor, and in view of a correlation between those amounts of variation in the drive signals and the amount of current, changing the servo control system characteristics according to measured amounts of variation, and setting a limit to the level of drive signals.
    Type: Application
    Filed: December 17, 2008
    Publication date: August 20, 2009
    Inventors: Takeyoshi KATAOKA, Seiji Imagawa, Munehiro Yonezawa
  • Publication number: 20070274166
    Abstract: With a high-density optical disc drive, although it is necessary to correct spherical aberrations which depend on a disc substrate thickness error, operation of an aberrations correction element takes time and therefore easy correction according to a disc radius degrades the operability of the apparatus. The present invention comprises an optical pickup unit including an objective lens and an aberrations correction lens, a focus actuator, a tracking actuator, a aberrations correction motor, a seek motor, an aberrations correction lens control module, a radius information detecting module, and a system control module.
    Type: Application
    Filed: January 11, 2007
    Publication date: November 29, 2007
    Applicants: Hitachi, Ltd., Hitachi-LG Data Storage, Inc.
    Inventor: Seiji Imagawa
  • Publication number: 20070177469
    Abstract: In an optical disc drive that needs an aberration correcting element for correcting spherical aberrations, it takes long time to conduct a processing operation of the aberration correcting element in an interlayer movement of a multilayer disc and a drive initializing operation. In order to eliminate the problem, an optical disc drive using a pickup includes a focus actuator for moving an objective lens in a rotation axis direction of a disc, a tracking actuator for moving the objective lens in a radial direction of the disc, an aberration corrector for correcting aberrations, and a feeder for moving the pickup in the disc radial direction. A control operation of the aberration corrector and a control operation of the feeder are conducted in parallel.
    Type: Application
    Filed: July 19, 2006
    Publication date: August 2, 2007
    Inventor: Seiji Imagawa
  • Publication number: 20070008836
    Abstract: An optical disk drive having a laser source for irradiating an optical beam onto an optical disk, a lens unit to focus the optical beam from the laser source onto the optical disk, a drive unit for driving the lens unit, and a high-frequency signal output unit for producing a high-frequency signal. The drive unit drives the lens unit by applying the high-frequency signal before the optical disk is started to reproduce, and drives it without applying the high-frequency signal after the optical disk is started to reproduce. Thus, it is possible to effectively control the aberration correction mechanism using a linear actuator.
    Type: Application
    Filed: February 27, 2006
    Publication date: January 11, 2007
    Inventors: Seiji Imagawa, Motoyuki Suzuki, Akio Fukushima
  • Publication number: 20060126466
    Abstract: An optical disc reproducing apparatus and an optical disc recording apparatus for reproducing an optical disc. The apparatus includes an optical pickup unit for irradiating a laser beam to the optical disc, an optical pickup drive unit for moving the optical pickup in the radial direction of the optical disc, and a motor unit for rotating the optical disc. When a tracking jump command is issued, the optical pickup drive unit moves the optical pickup unit in the radial direction of the optical disc at the timing in accordance with the rotation speed of the optical disc after the laser beam irradiated to the optical disc has passed the address information recording portion indicating the address of the optical disc.
    Type: Application
    Filed: December 13, 2005
    Publication date: June 15, 2006
    Inventors: Seiji Imagawa, Koichiro Nishimura
  • Patent number: 6657666
    Abstract: The purpose of the invention is to improve an operability of an image information recording and/or reproducing method and apparatus. A shot place extraction means 6 is established so that the means 6 can extract a shot place proposed by referring a map information 5 corresponding to a shot position on the map, and furthermore a shot object extraction means 7 is establishes to that the means 7 can extract a shot object proposed by referring the map information 5 corresponding to the shot object on the map based on the shot position, a distance between the shot position and the shot object, and a direction from the shot position to the shot object.
    Type: Grant
    Filed: June 14, 1999
    Date of Patent: December 2, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Seiji Imagawa, Hiroaki Ono, Shigemitsu Higuchi, Isao Nakagawa