Patents by Inventor Takashi Ohshima

Takashi Ohshima 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: 20240128049
    Abstract: An object of the invention is to provide an electron microscope capable of obtaining a sufficient energy resolution without forming a long drift space and capable of attaining high energy discrimination detection performance with approximately the same device size as in the related art. The electron microscope according to the invention includes a pulsed electron emission mechanism configured to emit an electron beam in a pulsed manner, and discriminates energy of signal electrons by discriminating the signal electrons, which are emitted from a sample by irradiating the sample with the electron beam, according to a time of flight (see FIG. 2).
    Type: Application
    Filed: August 31, 2021
    Publication date: April 18, 2024
    Inventors: Katsura TAKAGUCHI, Takashi OHSHIMA, Hideo MORISHITA, Yoichi OSE, Junichi KATANE, Toshihide AGEMURA, Michio HATANO
  • Publication number: 20240120168
    Abstract: An electron beam emitted from a photoexcited electron gun is increased in luminance. An electron gun 15 includes: a photocathode 1 including a substrate 11 and a photoelectric film 10; a light source 7 that emits pulsed excitation light; a condenser lens 2 that focuses the pulsed excitation light toward the photocathode; and an extractor electrode 3 that faces the photocathode and that accelerates an electron beam generated from the photoelectric film by focusing the pulsed excitation light by the condenser lens, transmitting the pulsed excitation light through the substrate of the photocathode, and causing the pulsed excitation light to be incident on the photocathode. The pulsed excitation light is condensed at different timings at different positions on the photoelectric film of the photocathode.
    Type: Application
    Filed: October 31, 2019
    Publication date: April 11, 2024
    Applicants: Hitachi High-Tech Corporation, Hitachi High-Tech Corporation
    Inventors: Takashi Ohshima, Hideo Morishita, Tatsuro Ide, Naohiro Kohmu, Momoyo Enyama, Yoichi Ose, Toshihide Agemura, Junichi Katane
  • Publication number: 20230402246
    Abstract: The apparatus includes: a photocathode including a substrate and a photoelectric film formed on the substrate; a light source configured to emit a pulsed excitation light; a condenser lens facing the substrate of the photocathode and configured to condense the pulsed excitation light toward the photocathode; a first anode electrode and a second anode electrode facing the photoelectric film of the photocathode; a first power supply configured to apply a first control voltage between the first anode electrode and the second anode electrode; and a second power supply configured to apply an acceleration voltage between the photocathode and the second anode electrode. The first anode electrode is disposed between the photocathode and the second anode electrode. A surface of the first anode electrode facing the second anode electrode has a recessed shape, and a surface of the second anode electrode facing the first anode electrode has a protruding shape.
    Type: Application
    Filed: December 22, 2020
    Publication date: December 14, 2023
    Inventors: Hideo MORISHITA, Takashi OHSHIMA, Yoichi OSE, Toshihide AGEMURA, Makoto KUWAHARA
  • Publication number: 20230335367
    Abstract: An activation mechanism is provided in an activation region of an electron gun, and includes a light source device 3 configured to irradiate a photocathode with excitation light, a heat generating element, an oxygen generation unit configured to generate oxygen by heating the heat generating element, and an emission current meter configured to monitor an emission current generated by electron emission when the photocathode 1 is irradiated with the excitation light from the light source device. In a surface activation process, the photocathode is irradiated with the excitation light from the light source device, an emission current amount of the photocathode is monitored by the emission current meter, the heat generating element is heated to generate oxygen by the oxygen generation unit, and the heating of the heat generating element is stopped when the emission current amount of the photocathode satisfies a predetermined stop criterion.
    Type: Application
    Filed: November 10, 2020
    Publication date: October 19, 2023
    Inventors: Takashi OHSHIMA, Hideo MORISHITA, Tatsuro IDE, Hiroyasu SHICHI, Yoichi OSE, Junichi KATANE
  • Patent number: 11784022
    Abstract: A scanning electron beam apparatus which two-dimensionally scans a sample by an electron beam to achieve high resolution even with a photoexcited electron source. The electron beam apparatus includes a photocathode including a substrate having a refractive index of more than 1.7 and a photoemissive film, a focusing lens configured to focus an excitation light toward the photocathode, an extractor electrode disposed facing the photocathode and configured to accelerate an electron beam generated from the photoemissive film by focusing the excitation light by the focusing lens and emitting the excitation light through the substrate, and an electron optics including a deflector configured to two-dimensionally scan a sample by the electron beam accelerated by the extractor electrode. For a spherical aberration of the focusing lens, a root mean square of the spherical aberration on the photoemissive film is equal to or less than 1/14 of a wavelength of the excitation light.
    Type: Grant
    Filed: January 28, 2019
    Date of Patent: October 10, 2023
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Takashi Ohshima, Tatsuro Ide, Hideo Morishita, Yoichi Ose, Tsunenori Nomaguchi, Toshihide Agemura
  • Publication number: 20230110667
    Abstract: A computer-tomography (CT) imaging system, comprising an imaging data acquisition system. The imaging data acquisition system includes a detector section, an aggregation section, and a storage section. The detection section includes a plurality of detector elements configured to convert radiation into electric signals. The aggregation section aggregates imaging data carried by the electric signals from the detector section. The storage section is arranged in a manner corresponding to the detector elements regarding an output from the detector section and an input to the aggregation section. The storage section includes a predetermined number of non-volatile memories configured to store the imaging data from the corresponding detector elements.
    Type: Application
    Filed: August 17, 2022
    Publication date: April 13, 2023
    Inventors: James Lawrence BEGELMAN, Kevin ZIMMERMAN, Thomas LABNO, John BAUMGART, Akira NISHIJIMA, Takashi OHSHIMA
  • Publication number: 20220406558
    Abstract: The electron gun is provided with a first anode electrode and a second anode electrode to generate an acceleration and deceleration electric field. A lens electric field makes it possible to irradiate a sample with an electron beam emitted from a part outside an optical axis of the photoelectric film without being blocked by a differential exhaust diaphragm. A wide range of electron beams off-optical axis can be used even in a high-brightness photocathode that requires high vacuum. As a result, the photoelectric film and the electron gun can be extended in life, can be stabilized, and can be increased in brightness. Further, it is possible to facilitate a control of emitting electron beams from a plurality of positions on the photoelectric film, a timing control of emitting electron beams from a plurality of positions, a condition control of an electron beam in an electron microscope using electron beams.
    Type: Application
    Filed: March 25, 2020
    Publication date: December 22, 2022
    Inventors: Hideo MORISHITA, Takashi OHSHIMA, Tatsuro IDE, Naohiro KOHMU, Toshihide AGEMURA, Yoichi OSE, Junichi KATANE
  • Publication number: 20220165536
    Abstract: A scanning electron beam apparatus which two-dimensionally scans a sample by an electron beam, to achieve high resolution even with a photoexcited electron source. The electron beam apparatus includes a photocathode including a substrate having a refractive index of more than 1.7 and a photoemissive film, a focusing lens configured to focus an excitation light toward the photocathode, an extractor electrode disposed facing the photocathode and configured to accelerate an electron beam generated from the photoemissive film by focusing the excitation light by the focusing lens and emitting the excitation light through the substrate, and an electron optics including a deflector configured to two-dimensionally scan a sample by the electron beam accelerated by the extractor electrode. For a spherical aberration of the focusing lens, a root mean square of the spherical aberration on the photoemissive film is equal to or less than 1/14 of a wavelength of the excitation light.
    Type: Application
    Filed: January 28, 2019
    Publication date: May 26, 2022
    Inventors: Takashi Ohshima, Tatsuro Ide, Hideo Morishita, Yoichi Ose, Tsunenori Nomaguchi, Toshihide Agemura
  • Patent number: 11322329
    Abstract: The invention provides an electron source including a columnar chip of a hexaboride single crystal, a metal pipe that holds the columnar chip of the hexaboride single crystal, and a filament connected to the metal pipe at a central portion. The columnar chip of the hexaboride single crystal is formed into a cone shape at a portion closer to a tip than a portion held in the metal pipe, and a tip end portion having the cone shape has a (310) crystal face. Schottky electrons are emitted from the (310) crystal face. According to the invention, it is possible to provide a novel electron source having monochromaticity, long-term stability of an emitter current, and high current density.
    Type: Grant
    Filed: August 27, 2018
    Date of Patent: May 3, 2022
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Toshiaki Kusunoki, Tomihiro Hashizume, Keigo Kasuya, Noriaki Arai, Hiromitsu Seino, Minoru Kaneda, Takashi Ohshima, Soichiro Matsunaga
  • Patent number: 11251011
    Abstract: To provide an electron microscope capable of performing the switching-over between normal illumination and annular illumination, wide-area irradiation, an interference pattern as desired or normal illumination in an expeditious and readily manner or achieving a better S/N ratio, the electron microscope comprises a photocathode 101 with negative electron affinity in use; an excitation optical system to excite the photocathode; and an electron optics system to irradiate an electron beam 13 generated from the photocathode by excitation light 12 irradiated through the excitation optical system onto a sample, the excitation optical system including a light source device 107 for the excitation light; and an optical modulation means 108 which is disposed in an optical path of the excitation light to perform spatial phase modulation to the excitation light.
    Type: Grant
    Filed: March 29, 2016
    Date of Patent: February 15, 2022
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Takashi Ohshima, Hiroyuki Minemura, Yumiko Anzai, Momoyo Enyama, Yoichi Ose, Toshihide Agemura
  • Patent number: 11185851
    Abstract: A macromolecules containing a metal and a use thereof as a catalyst are disclosed. The macromolecules containing a metal may be obtained by causing a ligand to react with a zinc compound or a cobalt compound. The ligand has an imidazole group that is bonded to a macromolecule via a linker. The metal-containing macromolecules are highly active as a catalyst, stable, and easy to recover and reuse.
    Type: Grant
    Filed: February 16, 2017
    Date of Patent: November 30, 2021
    Assignee: TAKASAGO INTERNATIONAL CORPORATION
    Inventors: Yoshimasa Matsushima, Takashi Ohshima
  • Publication number: 20210327674
    Abstract: The invention provides an electron source including a columnar chip of a hexaboride single crystal, a metal pipe that holds the columnar chip of the hexaboride single crystal, and a filament connected to the metal pipe at a central portion. The columnar chip of the hexaboride single crystal is formed into a cone shape at a portion closer to a tip than a portion held in the metal pipe, and a tip end portion having the cone shape has a (310) crystal face. Schottky electrons are emitted from the (310) crystal face. According to the invention, it is possible to provide a novel electron source having monochromaticity, long-term stability of an emitter current, and high current density.
    Type: Application
    Filed: August 27, 2018
    Publication date: October 21, 2021
    Inventors: Toshiaki KUSUNOKI, Tomihiro HASHIZUME, Keigo KASUYA, Noriaki ARAI, Hiromitsu SEINO, Minoru KANEDA, Takashi OHSHIMA, Soichiro MATSUNAGA
  • Publication number: 20210319970
    Abstract: In a photoexcited electron source, a condenser lens optimally designed on an assumption that excitation light passes through a transparent substrate having a predetermined thickness and a predetermined refractive index cannot focus a focal point of the excitation light well on a photocathode film when the transparent substrate is different. Therefore, an optical spherical aberration correction plate 21 having a refractive index equal to a refractive index of a substrate of a photocathode at a wavelength of the excitation light is disposed between the photocathode 1 and the condenser lens 2. Alternatively, an optical spherical aberration corrector 20 configured to diverge or focus parallel light emitted to the condenser lens is provided. Accordingly, flares of the electron beam can be reduced and brightness of the photoexcited electron source can be increased.
    Type: Application
    Filed: May 21, 2018
    Publication date: October 14, 2021
    Inventors: Takashi Ohshima, Hiroyuki Minemura, Manabu Shiozawa, Hideo Morishita
  • Patent number: 11087947
    Abstract: To provide an electron microscope capable of performing the switching-over between normal illumination and annular illumination, wide-area irradiation, an interference pattern as desired or normal illumination in an expeditious and readily manner or achieving a better S/N ratio, the electron microscope comprises a photocathode 101 with negative electron affinity in use; an excitation optical system to excite the photocathode; and an electron optics system to irradiate an electron beam 13 generated from the photocathode by excitation light 12 irradiated through the excitation optical system onto a sample, the excitation optical system including a light source device 107 for the excitation light; and an optical modulation means 108 which is disposed in an optical path of the excitation light to perform spatial phase modulation to the excitation light.
    Type: Grant
    Filed: March 29, 2016
    Date of Patent: August 10, 2021
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Takashi Ohshima, Hiroyuki Minemura, Yumiko Anzai, Momoyo Enyama, Yoichi Ose, Toshihide Agemura
  • Patent number: 11062892
    Abstract: The objective of the present invention is to provide a charged particle detector and a charged particle beam device with which it is possible to acquire a high luminous output while rapidly eliminating charged particles that are incident to a scintillator. In order to achieve said objective the present invention proposes: a charged particle detector provided with a light-emitting unit including a laminated structure obtained by laminating a GaInN-containing layer and a GaN layer, and provided with a conductive layer that is in contact with the GaInN-containing layer on the charged particle incidence surface side of the laminated structure; and a charged particle beam device.
    Type: Grant
    Filed: January 25, 2017
    Date of Patent: July 13, 2021
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Shin Imamura, Takashi Ohshima, Tomonobu Tsuchiya, Hajime Kawano, Makoto Suzuki
  • Patent number: 10984979
    Abstract: The disclosure provides a charged particle detector including a scintillator that emits light with stable intensity and obtains high light emission intensity regardless of an energy of an incident electron. The disclosure provides the charged particle detector including: a first light-emitting part (21) in which a layer containing Ga1-x-yAlxInyN (where 0?x<1, 0?y<1) and a layer containing GaN are alternately laminated; a second light-emitting part (23) in which the layer containing Ga1-x-yAlxInyN (where 0?x<1, 0?y<1) and the layer containing GaN are alternately laminated; and a non-light-emitting part (22) that is interposed between the first light-emitting part (21) and the second light-emitting part (23) (see FIG. 2).
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: April 20, 2021
    Assignee: HITACHI HIGH-TECH CORPORATION
    Inventors: Shin Imamura, Takashi Ohshima, Tomonobu Tsuchiya, Hajime Kawano, Shahedul Hoque, Shunsuke Mizutani, Makoto Suzuki
  • Publication number: 20200303152
    Abstract: To provide an electron microscope capable of performing the switching-over between normal illumination and annular illumination, wide-area irradiation, an interference pattern as desired or normal illumination in an expeditious and readily manner or achieving a better S/N ratio, the electron microscope comprises a photocathode 101 with negative electron affinity in use; an excitation optical system to excite the photocathode; and an electron optics system to irradiate an electron beam 13 generated from the photocathode by excitation light 12 irradiated through the excitation optical system onto a sample, the excitation optical system including a light source device 107 for the excitation light; and an optical modulation means 108 which is disposed in an optical path of the excitation light to perform spatial phase modulation to the excitation light.
    Type: Application
    Filed: March 29, 2016
    Publication date: September 24, 2020
    Inventors: Takashi OHSHIMA, Hiroyuki MINEMURA, Yumiko ANZAI, Momoyo ENYAMA, Yoichi OSE, Toshihide AGEMURA
  • Patent number: 10707046
    Abstract: An electron source that can be used stably for a long time even when hexaboride is used, and an electron beam device using the electron source are provided. The invention is directed to an electron source which includes a filament made of a metal, a metal tube that is fixed to the filament and has a plurality of recesses disposed at least in two axial directions so as to surround a central axis at an outer periphery, and a columnar hexaboride tip that emits an electron, is disposed so as to protrude from the inside of the metal tube to a side opposite to the filament, and is in contact with a bottom of each of the plurality of recesses of the metal tube.
    Type: Grant
    Filed: December 8, 2017
    Date of Patent: July 7, 2020
    Assignee: Hitachi High-Tech Corporation
    Inventors: Toshiaki Kusunoki, Keigo Kasuya, Takashi Ohshima, Tomihiro Hashizume, Noriaki Arai, Yoichi Ose
  • Patent number: 10586674
    Abstract: In order to provide a stable hexaboride single-crystal field emission electron source capable of heat-flashing, this field emission electron source is provided with a metal filament, a metal tube joined thereto, a hexaboride tip that emits electrons, and graphite sheets that are independent of the metal tube and the hexaboride tip. The hexaboride tip is arranged so as not to be in structural contact with the metal tube due to the graphite sheets. The hexaboride tip, the graphite sheets, and the metal tube are configured so as to be mechanically and electrically in contact with one another.
    Type: Grant
    Filed: November 24, 2016
    Date of Patent: March 10, 2020
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Toshiaki Kusunoki, Tomihiro Hashizume, Keigo Kasuya, Takashi Ohshima, Yusuke Sakai, Yoichi Ose, Noriaki Arai
  • Patent number: 10522319
    Abstract: An electron beam apparatus which can stably achieve high spatial resolution also during low acceleration observation using CeB6 for the CFE electron source is provided. In an electron beam apparatus having a CFE electron source, the emitter of the electron beam of the CFE electron source is Ce hexaboride or a hexaboride of a lanthanoid metal heavier than Ce, the hexaboride emits the electron beam from the {310} plane, and the number of the atoms of the lanthanoid metal on the {310} plane is larger than the number of boron molecules comprising six boron atoms on the {310} plane.
    Type: Grant
    Filed: October 13, 2016
    Date of Patent: December 31, 2019
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Keigo Kasuya, Noriaki Arai, Toshiaki Kusunoki, Takashi Ohshima, Tomihiro Hashizume, Yusuke Sakai