Patents by Inventor Katsumi Sasata

Katsumi Sasata 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: 11988880
    Abstract: Provided are a small-sized optical coupling system and an optical communication device using the optical coupling system. An optical coupling system includes a liquid crystal optical element, and a photonic device having a plurality of photonic chips, and couples an optical fiber to the photonic device, in which each of the photonic chips includes a grating coupler, the liquid crystal optical element separates incident signal light depending on at least one of polarization or a wavelength to emit light in different directions, and each separated signal light component is incident into the grating coupler of the corresponding photonic chip.
    Type: Grant
    Filed: August 12, 2022
    Date of Patent: May 21, 2024
    Assignee: FUJIFILM Corporation
    Inventors: Yukito Saitoh, Katsumi Sasata, Hiroshi Sato
  • Publication number: 20240094579
    Abstract: A light guide element includes: a light guide plate; and a diffraction element that is disposed on a main surface of the light guide plate, in which the diffraction element includes a liquid crystal layer that is formed of a liquid crystal composition including a liquid crystal compound and has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, a refractive index of the light guide plate is 1.70 or higher, and in a case where the refractive index of the light guide plate is represented by nd and a refractive index of the liquid crystal layer is represented by nk, nk?nd?0 is satisfied.
    Type: Application
    Filed: October 23, 2023
    Publication date: March 21, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Fumitake MITOBE, Katsumi SASATA, Yukito SAITOH, Akiko WATANO
  • Publication number: 20240077664
    Abstract: Provided is a sensor having a high SN ratio. The sensor includes a light source, a band pass filter, and a light-receiving element, in which the band pass filter includes two cholesteric liquid crystal layers and a discontinuous layer disposed between the two cholesteric liquid crystal layers, in the two cholesteric liquid crystal layers, helical twisted directions and helical pitches are the same, and in a case where the discontinuous layer is a layer other than a cholesteric liquid crystal layer and a wavelength having a lowest reflectivity in a selective reflection wavelength range of the band pass filter is represented by ?m [nm], a thickness [nm] is in a range of “30×(?m/550) to 150×(?m/550)”.
    Type: Application
    Filed: October 25, 2023
    Publication date: March 7, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Hiroshi SATO, Katsumi SASATA, Yukito SAITOH
  • Publication number: 20240069257
    Abstract: Provided are a cholesteric liquid crystal layer having a high diffraction efficiency, a method of forming the same, and a laminate, a light guide element, and an image display device that include the cholesteric liquid crystal layer. The cholesteric liquid crystal layer is obtained by immobilizing a cholesteric liquid crystalline phase, in which the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction, in a cross-section observed with a SEM, bright portions and dark portions are tilted, in a case where a tilt angle of a direction in which an in-plane retardation is minimum with respect to a normal line in a slow axis plane or a fast axis plane is represented by ?2, an absolute value of an optical axis tilt angle ? represented by “sin ?2=n·sin ? (n represents an average refractive index of the cholesteric liquid crystal layer)” is 5° or more.
    Type: Application
    Filed: October 16, 2023
    Publication date: February 29, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Katsumi SASATA, Hiroshi SATO, Yukito SAITOH
  • Publication number: 20240045334
    Abstract: An object is to provide an exposure method of a photoalignment layer in which an alignment pattern having no disorder can be formed.
    Type: Application
    Filed: October 11, 2023
    Publication date: February 8, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Hiroshi SATO, Takashi YONEMOTO, Katsumi SASATA
  • Publication number: 20240045335
    Abstract: An object is to provide an exposure method of a photoalignment layer in which an alignment pattern having no disorder can be formed. The exposure method of a photoalignment layer includes an exposure step of disposing an exposure mask and a substrate that includes a coating film including a compound having a photo-aligned group such that the exposure mask and the coating film face each other, irradiating the coating film with light to which the compound is photosensitive from the exposure mask side, and exposing the coating film to form an alignment pattern, in which the light is circularly polarized light having an ellipticity of 0.7 to 1.
    Type: Application
    Filed: October 11, 2023
    Publication date: February 8, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Hiroshi SATO, Katsumi SASATA, Takashi YONEMOTO
  • Patent number: 11886071
    Abstract: A light guide element includes: a light guide plate; and a diffraction element that is disposed on a main surface of the light guide plate, in which the diffraction element includes a liquid crystal layer that is formed of a liquid crystal composition including a liquid crystal compound and has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, a refractive index of the light guide plate is 1.70 or higher, and in a case where the refractive index of the light guide plate is represented by nd and a refractive index of the liquid crystal layer is represented by nk, nk?nd?0 is satisfied.
    Type: Grant
    Filed: September 30, 2022
    Date of Patent: January 30, 2024
    Assignee: FUJIFILM Corporation
    Inventors: Fumitake Mitobe, Katsumi Sasata, Yukito Saitoh, Akiko Watano
  • Patent number: 11835744
    Abstract: Provided is a sensor having a high SN ratio. The sensor includes a light source, a band pass filter, and a light-receiving element, in which the band pass filter includes two cholesteric liquid crystal layers and a discontinuous layer disposed between the two cholesteric liquid crystal layers, in the two cholesteric liquid crystal layers, helical twisted directions and helical pitches are the same, and in a case where the discontinuous layer is a layer other than a cholesteric liquid crystal layer and a wavelength having a lowest reflectivity in a selective reflection wavelength range of the band pass filter is represented by ?m [nm], a thickness [nm] is in a range of “30×(?m/550) to 150×(?m/550)”.
    Type: Grant
    Filed: November 9, 2021
    Date of Patent: December 5, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Hiroshi Sato, Katsumi Sasata, Yukito Saitoh
  • Patent number: 11828960
    Abstract: Provided are a cholesteric liquid crystal layer having a high diffraction efficiency, and a laminate, a light guide element, and an image display device that include the same. The cholesteric liquid crystal layer is obtained by immobilizing a cholesteric liquid crystalline phase, in which the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction, in a case where a tilt angle of a direction in which an in-plane retardation is minimum with respect to a normal line in a slow axis plane or a fast axis plane is represented by ?2, an absolute value of an optical axis tilt angle ? represented by “sin ?2=n·sin ? (n represents an average refractive index of the cholesteric liquid crystal layer)” is 5° or more.
    Type: Grant
    Filed: June 10, 2021
    Date of Patent: November 28, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Katsumi Sasata, Hiroshi Sato, Yukito Saitoh
  • Patent number: 11796854
    Abstract: Provided are an optical member in which emission of stray light to the outside can be suppressed and an image display apparatus. The optical member includes: a light guide element including a light guide plate and an incidence diffraction element and an emission diffraction element that are disposed on a main surface of the light guide plate; and a polarization element that blocks transmission of light leaking to a side of the emission diffraction element opposite to an emission side, wherein the emission diffraction element is a polarization diffraction element, the polarization element is disposed on the side of the emission diffraction element opposite to the emission side, and the polarization element is disposed at a position overlapping the emission diffraction element in a plane direction of the main surface of the light guide plate.
    Type: Grant
    Filed: May 24, 2022
    Date of Patent: October 24, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Hiroshi Sato, Katsumi Sasata, Yukito Saitoh
  • Patent number: 11796880
    Abstract: Provided are a liquid crystal diffraction element that diffracts incident light while allowing transmission of the incident light and has wavelength selectivity, and a laminated diffraction element.
    Type: Grant
    Filed: November 8, 2021
    Date of Patent: October 24, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Yukito Saitoh, Katsumi Sasata, Hiroshi Sato
  • Patent number: 11782196
    Abstract: Provided are a cholesteric liquid crystal layer that diffracts specific circularly polarized light in a specific wavelength range by transmission, and a method of forming the cholesteric liquid crystal layer. The cholesteric liquid crystal layer is obtained by immobilizing a cholesteric liquid crystalline phase, in which the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction, in a cross-section of the cholesteric liquid crystal layer observed with a scanning electron microscope, bright portions and dark portions derived from the cholesteric liquid crystalline phase are tilted at 80° or more with respect to a main surface of the cholesteric liquid crystal layer.
    Type: Grant
    Filed: November 12, 2021
    Date of Patent: October 10, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Katsumi Sasata, Hiroshi Sato, Yukito Saitoh
  • Publication number: 20230288719
    Abstract: An optical element includes a light guide plate, an incidence portion, and an emission portion, in which the incidence/emission portion includes an ?1 diffraction element having a diffraction period ?1, an ?2 diffraction element having a diffraction period ?2, and an ?3 diffraction element having a diffraction period ?3, “?1:?2:?3 = 1: 1/?2± 0.015: ½ ± 0.015” is satisfied, an angle between periodic directions of the ?1 diffraction element and the ?2 diffraction element and an angle between periodic directions of the ?2 diffraction element and the ?3 diffraction element is 45° or 135° (± 0.5°), and an angle between the periodic directions of the ?2 diffraction elements in the incidence portion and the emission portion is any one of 0°, 90°, 180°, or 270° (± 0.5°).
    Type: Application
    Filed: December 13, 2022
    Publication date: September 14, 2023
    Applicant: FUJIFILM Corporation
    Inventors: Fumitake MITOBE, Katsumi SASATA, Hiroshi SATO, Akiko WATANO, Yukito SAITOH
  • Publication number: 20230236353
    Abstract: Provided is an optical element that can display a clear image having no blurriness in AR glasses or the like. The optical element includes: a substrate; and a laminate that is provided on the substrate and where a plurality of liquid crystal layers obtained by aligning a liquid crystal compound are laminated, in which the liquid crystal layers have a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, and in at least one of the liquid crystal layers, an arithmetic mean value of differences between maximum film thicknesses and minimum film thicknesses obtained by observing 10 cross-sections with a scanning electron microscope is 0.1 ?m or less.
    Type: Application
    Filed: March 29, 2023
    Publication date: July 27, 2023
    Applicant: FUJIFILM Corporation
    Inventors: Akiko WATANO, Ryuji SANETO, Katsumi SASATA, Fumitake MITOBE, Hiroshi SATO, Yukito SAITOH
  • Publication number: 20230229002
    Abstract: Provided are an optical element that can make the brightness of light emitted from a light guide plate uniform, a light guide element, and an image display device. The optical element includes a patterned cholesteric liquid crystal layer that is obtained by immobilizing a cholesteric liquid crystalline phase, in which the patterned cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction, and the patterned cholesteric liquid crystal layer has regions having different pitches of helical structures in a plane.
    Type: Application
    Filed: February 13, 2023
    Publication date: July 20, 2023
    Applicant: FUJIFILM Corporation
    Inventors: Hiroshi SATO, Yukito SAITOH, Ayako MURAMATSU, Daisuke KASHIWAGI, Katsumi SASATA
  • Patent number: 11693278
    Abstract: Provided are a liquid crystal diffraction element which exhibits low scattering and high sharpness of diffracted light, and a method for producing the same.
    Type: Grant
    Filed: March 24, 2022
    Date of Patent: July 4, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Yukito Saitoh, Keisuke Kodama, Hiroshi Sato, Katsumi Sasata
  • Publication number: 20230168538
    Abstract: An optical element comprising: a cholesteric liquid crystal layer obtained by cholesteric alignment of a liquid crystal compound, in which the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, a helical pitch of a helical axis direction in the cholesteric alignment gradually changes in a thickness direction of the cholesteric liquid crystal layer, and the cholesteric liquid crystal layer has a peak of reflection at each of a first wavelength ? and a second wavelength ?/2.
    Type: Application
    Filed: January 26, 2023
    Publication date: June 1, 2023
    Applicant: FUJIFILM Corporation
    Inventors: Yukito SAITOH, Akiko WATANO, Fumitake MITOBE, Hiroshi SATO, Katsumi SASATA
  • Patent number: 11650448
    Abstract: Provided are a liquid crystal diffraction element that can make the brightness of light emitted from a light guide plate uniform and a light guide element. The liquid crystal diffraction element includes: an optically-anisotropic layer that is formed of a composition including a liquid crystal compound, in which the optically-anisotropic layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound continuously rotates in at least one in-plane direction, and a diffraction efficiency of the optically-anisotropic layer increases from one side to another side in the one in-plane direction.
    Type: Grant
    Filed: June 10, 2021
    Date of Patent: May 16, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Katsumi Sasata, Hiroshi Sato, Yukito Saitoh
  • Patent number: 11630308
    Abstract: Provided are an optical element that can make the brightness of light emitted from a light guide plate uniform, a light guide element, and an image display device. The optical element includes a patterned cholesteric liquid crystal layer that is obtained by immobilizing a cholesteric liquid crystalline phase, in which the patterned cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction, and the patterned cholesteric liquid crystal layer has regions having different pitches of helical structures in a plane.
    Type: Grant
    Filed: September 28, 2020
    Date of Patent: April 18, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Hiroshi Sato, Yukito Saitoh, Ayako Muramatsu, Daisuke Kashiwagi, Katsumi Sasata
  • Patent number: 11592700
    Abstract: Provided are: a light guide element that includes an intermediate diffraction element to expand exit pupil such that a light utilization efficiency is high and a decrease in the brightness of an image to be displayed can be suppressed; and an image display apparatus.
    Type: Grant
    Filed: May 25, 2022
    Date of Patent: February 28, 2023
    Assignee: FUJIFILM Corporation
    Inventors: Hiroshi Sato, Katsumi Sasata, Yukito Saitoh