Patents by Inventor Kazunobu Kojima

Kazunobu Kojima 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: 20230392280
    Abstract: An object of the present invention is to provide a GaN crystal long in light emission lifetime by time-resolved photoluminescence measurement and provide high-quality GaN crystal and GaN substrate that have few specified crystal defects affecting the light emission lifetime. A gallium nitride crystal having a light emission lifetime by time-resolved photoluminescence measurement, of 5 ps or more and 200 ps or less, and satisfying at least one of the following requirement (i) and requirement (ii): (i) an FWHM in a 004 diffraction X-ray rocking curve is 50 arcsec or less at least one position of the crystal; and (ii) a dislocation density is 5×106 cm?2 or less.
    Type: Application
    Filed: August 24, 2023
    Publication date: December 7, 2023
    Applicants: MITSUBISHI CHEMICAL CORPORATION, THE JAPAN STEEL WORKS, LTD., TOHOKU UNIVERSITY
    Inventors: Yutaka MIKAWA, Hirotaka IKEDA, Quanxi BAO, Kouhei KURIMOTO, Kohei SHIMA, Kazunobu KOJIMA, Toru ISHIGURO, Shigefusa CHICHIBU
  • Patent number: 11245113
    Abstract: A secondary battery includes: a first oxide semiconductor having a first conductivity type; a first charging layer disposed on the first oxide semiconductor layer, and composed by including a first insulating material and a second oxide semiconductor having the first conductivity type; a second charging layer disposed on the first charging layer; a third oxide semiconductor layer having a second conductivity type disposed on the second charging layer; and a hydroxide layer disposed between the first charging layer and the third oxide semiconductor layer, and containing a hydroxide of a metal constituting the third oxide semiconductor layer. The highly reliable secondary battery is capable of improving an energy density and increasing battery characteristics (electricity accumulation capacity).
    Type: Grant
    Filed: February 26, 2019
    Date of Patent: February 8, 2022
    Assignee: Kabushiki Kaisha Nihon Micronics
    Inventors: Takashi Tonokawa, Yutaka Kosaka, Kazuyuki Tsunokuni, Hikaru Takano, Shigefusa Chichibu, Kazunobu Kojima
  • Patent number: 11217726
    Abstract: To improve a wall plug efficiency in a nitride semiconductor light-emitting element for extracting ultraviolet light emitted from an active layer toward an n-type nitride semiconductor layer side to outside of the element.
    Type: Grant
    Filed: February 14, 2018
    Date of Patent: January 4, 2022
    Assignee: SOKO KAGAKU CO., LTD.
    Inventors: Akira Hirano, Yosuke Nagasawa, Shigefusa Chichibu, Kazunobu Kojima
  • Publication number: 20210043804
    Abstract: To improve a wall plug efficiency in a nitride semiconductor light-emitting element for extracting ultraviolet light emitted from an active layer toward an n-type nitride semiconductor layer side to outside of the element.
    Type: Application
    Filed: February 14, 2018
    Publication date: February 11, 2021
    Applicant: Soko Kagaku Co., Ltd.
    Inventors: Akira HIRANO, Yosuke NAGASAWA, Shigefusa CHICHIBU, Kazunobu KOJIMA
  • Patent number: 10643849
    Abstract: A manufacturing method of a nitride semiconductor ultraviolet light-emitting element having a peak emission wavelength of 285 nm or shorter comprises a first step of forming an n-type semiconductor layer composed of an n-type AlXGa1-XN-based semiconductor (1?X?0.5) on an upper surface of an underlying portion including a sapphire substrate, a second step of forming, above the n-type semiconductor layer, an active layer that includes a light-emitting layer composed of an AlYGa1-YN-based semiconductor (X>Y>0) and that is composed of an AlGaN-based semiconductor as a whole, and a third step of forming a p-type semiconductor layer composed of a p-type AlZGa1-ZN-based semiconductor (1?Z>Y) above the active layer. In the manufacturing method, a growth temperature at the second step is higher than 1200° C. and equal to or higher than a growth temperature at the first step.
    Type: Grant
    Filed: November 8, 2017
    Date of Patent: May 5, 2020
    Assignee: SOKO KAGAKU CO., LTD.
    Inventors: Akira Hirano, Yosuke Nagasawa, Shigefusa Chichibu, Kazunobu Kojima
  • Publication number: 20190228972
    Abstract: A manufacturing method of a nitride semiconductor ultraviolet light-emitting element having a peak emission wavelength of 285 nm or shorter comprises a first step of forming an n-type semiconductor layer composed of an n-type AlXGa1-XN-based semiconductor (1?X?0.5) on an upper surface of an underlying portion including a sapphire substrate, a second step of forming, above the n-type semiconductor layer, an active layer that includes a light-emitting layer composed of an AlYGa1-YN-based semiconductor (X>Y>0) and that is composed of an AlGaN-based semiconductor as a whole, and a third step of forming a p-type semiconductor layer composed of a p-type AlZGa1-ZN-based semiconductor (1?Z>Y) above the active layer. In the manufacturing method, a growth temperature at the second step is higher than 1200° C. and equal to or higher than a growth temperature at the first step.
    Type: Application
    Filed: November 8, 2017
    Publication date: July 25, 2019
    Applicant: Soko Kagaku Co., Ltd.
    Inventors: Akira HIRANO, Yosuke NAGASAWA, Shigefusa CHICHIBU, Kazunobu KOJIMA
  • Publication number: 20190190024
    Abstract: A secondary battery includes: a first oxide semiconductor having a first conductivity type; a first charging layer disposed on the first oxide semiconductor layer, and composed by including a first insulating material and a second oxide semiconductor having the first conductivity type; a second charging layer disposed on the first charging layer; a third oxide semiconductor layer having a second conductivity type disposed on the second charging layer; and a hydroxide layer disposed between the first charging layer and the third oxide semiconductor layer, and containing a hydroxide of a metal constituting the third oxide semiconductor layer. The highly reliable secondary battery is capable of improving an energy density and increasing battery characteristics (electricity accumulation capacity).
    Type: Application
    Filed: February 26, 2019
    Publication date: June 20, 2019
    Inventors: Takashi TONOKAWA, Yutaka KOSAKA, Kazuyuki TSUNOKUNI, Hikaru TAKANO, Shigefusa CHICHIBU, Kazunobu KOJIMA
  • Patent number: 7408963
    Abstract: A medical laser apparatus suitable for medical treatment, which is capable of obtaining a plurality of visible laser beams each having a different wavelength, but which has an inexpensive structure.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: August 5, 2008
    Assignee: Nidek Co., Ltd.
    Inventors: Kenichi Hayashi, Kazunobu Kojima
  • Patent number: 7262552
    Abstract: A plasma display apparatus is equipped with a signal input terminal responsive to a user's application. The plasma display apparatus includes a panel including a pair of substrates, wherein at least one of the substrates is transparent. The substrates are placed opposite to each other to form a discharge space in between, and electrodes are provided to the substrate. The plasma display apparatus also includes a display driving circuit block, disposed on a chassis and equipped with at least one signal inputting connector which applies a signal to the panel to perform displaying, and an input signal circuit block detachable to the signal inputting connector of the display driving circuit block.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: August 28, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tomihide Nomoto, Kazunobu Kojima, Akira Mizuno
  • Patent number: 7250725
    Abstract: A plasma display apparatus is equipped with a signal input terminal responsive to a user's application. The plasma display apparatus includes a panel including a pair of substrates, wherein at least one of the substrates is transparent. The substrates are placed opposite to each other to form a discharge space in between, and electrodes are provided to the substrate. The plasma display apparatus also includes a display driving circuit block, disposed on a chassis and equipped with at least one signal inputting connector which applies a signal to the panel to perform displaying, and an input signal circuit block detachable to the signal inputting connector of the display driving circuit block.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: July 31, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tomihide Nomoto, Kazunobu Kojima, Akira Mizuno
  • Publication number: 20070078449
    Abstract: A medical laser apparatus suitable for medical treatment, which is capable of obtaining a plurality of visible laser beams each having a different wavelength, but which has an inexpensive structure.
    Type: Application
    Filed: September 27, 2006
    Publication date: April 5, 2007
    Applicant: NIDEK CO., LTD.
    Inventors: Kenichi Hayashi, Kazunobu Kojima
  • Patent number: 7091665
    Abstract: A plasma display apparatus is equipped with a signal input terminal responsive to a user's application. The plasma display apparatus includes a panel including a pair of substrates, wherein at least one of the substrates is transparent. The substrates are placed opposite to each other to form a discharge space in between, and electrodes are provided to the substrate. The plasma display apparatus also includes a display driving circuit block, disposed on a chassis and equipped with at least one signal inputting connector which applies a signal to the panel to perform displaying, and an input signal circuit block detachable to the signal inputting connector of the display driving circuit block.
    Type: Grant
    Filed: June 12, 2002
    Date of Patent: August 15, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tomihide Nomoto, Kazunobu Kojima, Akira Mizuno
  • Publication number: 20060152909
    Abstract: A plasma display apparatus is equipped with a signal input terminal responsive to a user's application. The plasma display apparatus includes a panel including a pair of substrates, wherein at least one of the substrates is transparent. The substrates are placed opposite to each other to form a discharge space in between, and electrodes are provided to the substrate. The plasma display apparatus also includes a display driving circuit block, disposed on a chassis and equipped with at least one signal inputting connector which applies a signal to the panel to perform displaying, and an input signal circuit block detachable to the signal inputting connector of the display driving circuit block.
    Type: Application
    Filed: March 1, 2006
    Publication date: July 13, 2006
    Inventors: Tomihide Nomoto, Kazunobu Kojima, Akira Mizuno
  • Publication number: 20060145615
    Abstract: A plasma display apparatus is equipped with a signal input terminal responsive to a user's application. The plasma display apparatus includes a panel including a pair of substrates, wherein at least one of the substrates is transparent. The substrates are placed opposite to each other to form a discharge space in between, and electrodes are provided to the substrate. The plasma display apparatus also includes a display driving circuit block, disposed on a chassis and equipped with at least one signal inputting connector which applies a signal to the panel to perform displaying, and an input signal circuit block detachable to the signal inputting connector of the display driving circuit block.
    Type: Application
    Filed: March 1, 2006
    Publication date: July 6, 2006
    Inventors: Tomihide Nomoto, Kazunobu Kojima, Akira Mizuno
  • Patent number: 6813159
    Abstract: In a display device, attached to a plate-type chassis (2) is a PDP (1) having a display screen on which videos are displayed and a circuit board (9) on which a circuit driving the PDP (1) is arranged. The circuit board (9) is shielded with respect to the PDP (1) thanks to the chassis (2), and thus does not receive any unwanted radiation noise radiated by the PDP (1). The display device further includes a back cover (6) and a cabinet (7) each having conductivity. The back cover (6) and the cabinet (7) house therein the PDP (1) and the circuit board (9) attached to the chassis (2). The back cover (6) and the cabinet (7) are both electrically insulated from the chassis (2). Therefore, any unwanted radiation noise from the PDP (1) and the circuit on the circuit board (9) is stopped leaking to the outside.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: November 2, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shoichi Irie, Kazunobu Kojima
  • Publication number: 20040027073
    Abstract: A plasma display apparatus is equipped with a signal input terminal responsive to a user's application. The plasma display apparatus includes a panel including a pair of substrates, at least one of the substrates is transparent, placed oppositely to each other to form a discharge space in between, and electrodes being provided to the substrates; a display driving circuit block, disposed on a chassis and equipped with at least one signal inputting connector which applies a signal to the panel to perform displaying; and an input signal circuit block detachable to the signal inputting connector of the display driving circuit block.
    Type: Application
    Filed: June 2, 2003
    Publication date: February 12, 2004
    Inventors: Tomihide Nomoto, Kazunobu Kojima, Akira Mizuno
  • Patent number: 6679876
    Abstract: The present invention is intended to provide a corneal surgery apparatus which enables a surgical operator to accurately ablate a cornea in part. The corneal surgery apparatus for ablating part of a cornea by irradiating a laser beam onto the cornea of a patient's eye comprises an irradiation optical system for irradiating the laser beam emitted from a laser light source onto the cornea, an aperture, which is disposed in the irradiation optical system, profiling a cross-sectional region of the beam perpendicular to an optical axis of the irradiation into one or more small regions, and correcting device for correcting an intensity distribution of the laser beam, which is changed when the beam passes through the aperture, to a specified intensity distribution.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: January 20, 2004
    Assignee: Nidek Co., Ltd.
    Inventors: Naoyuki Kondo, Kazunobu Kojima, Satoshi Imaizumi
  • Patent number: 6650676
    Abstract: A gas laser apparatus includes a chamber in which laser medium gas is sealingly filled; a pair of main discharge electrodes arranged opposite to each other in the chamber; and a fan disposed in the chamber; wherein the chamber has an inner wall of a substantially elliptic shape in a plane perpendicular to a lengthwise direction of the chamber, and a part of the inner wall being between the fan and the main discharge electrodes serves as a guide for guiding the gas made to flow by the fan toward the main discharge electrodes.
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: November 18, 2003
    Assignee: Nidek Co., Ltd.
    Inventor: Kazunobu Kojima
  • Publication number: 20030169573
    Abstract: In a display device, attached to a plate-type chassis (2) is a PDP (1) having a display screen on which videos are displayed and a circuit board (9) on which a circuit driving the PDP (1) is arranged. The circuit board (9) is shielded with respect to the PDP (1) thanks to the chassis (2), and thus does not receive any unwanted radiation noise radiated by the PDP (1). The display device further includes a back cover (6) and a cabinet (7) each having conductivity. The back cover (6) and the cabinet (7) house therein the PDP (1) and the circuit board (9) attached to the chassis (2). The back cover (6) and the cabinet (7) are both electrically insulated from the chassis (2). Therefore, any unwanted radiation noise from the PDP (1) and the circuit on the circuit board (9) is stopped leaking to the outside.
    Type: Application
    Filed: March 13, 2003
    Publication date: September 11, 2003
    Inventors: Shoichi Irie, Kazunobu Kojima
  • Patent number: 6560124
    Abstract: In a display device, attached to a plate-type chassis (2) is a PDP (1) having a display screen on which videos are displayed and a circuit board (9) on which a circuit driving the PDP (1) is arranged. The circuit board (9) is shielded with respect to the PDP (1) thanks to the chassis (2), and thus does not receive any unwanted radiation noise radiated by the PDP (1). The display device further includes a back cover (6) and a cabinet (7) each having conductivity. The back cover (6) and the cabinet (7) house therein the PDP (1) and the circuit board (9) attached to the chassis (2). The back cover (6) and the cabinet (7) are both electrically insulated from the chassis (2). Therefore, any unwanted radiation noise from the PDP (1) and the circuit on the circuit board (9) is stopped leaking to the outside.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: May 6, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shoichi Irie, Kazunobu Kojima