Patents by Inventor Tetsuya Sadahiro

Tetsuya Sadahiro 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: 20240077665
    Abstract: Provided are a light guide plate, an area light source device, a display device, and manufacturing method for the light guide plate such that the occurrence of uneven luminance is suppressed. The light guide plate is characterized in that the light guide plate has a light entrance surface through which light enters, a light exit surface intersecting with the light entrance surface and through which light is output, and an opposite surface facing the light entrance surface, wherein the light entering through the light entrance surface is guided to the opposite surface side and output from the light exit surface, and the refractive index Nx in a direction perpendicular to the light entrance surface is higher than the refractive index Ny in a direction parallel to the light exit surface and parallel to the light entrance surface.
    Type: Application
    Filed: November 8, 2023
    Publication date: March 7, 2024
    Applicant: Dai Nippon Printing Co., Ltd.
    Inventors: Kohei KOMIZO, Tetsuya SADAHIRO, Hironori HASHIGUCHI, Koujiro OHKAWA
  • Publication number: 20230055455
    Abstract: Provided are a light guide plate, an area light source device, a display device, and manufacturing method for the light guide plate such that the occurrence of uneven luminance is suppressed. The light guide plate is characterized in that the light guide plate has a light entrance surface through which light enters, a light exit surface intersecting with the light entrance surface and through which light is output, and an opposite surface facing the light entrance surface, wherein the light entering through the light entrance surface is guided to the opposite surface side and output from the light exit surface, and the refractive index Nx in a direction perpendicular to the light entrance surface is higher than the refractive index Ny in a direction parallel to the light exit surface and parallel to the light entrance surface.
    Type: Application
    Filed: October 13, 2022
    Publication date: February 23, 2023
    Applicant: Dai Nippon Printing Co., Ltd.
    Inventors: Kohei KOMIZO, Tetsuya SADAHIRO, Hironori HASHIGUCHI, Koujiro OHKAWA
  • Patent number: 11513276
    Abstract: Provided are a light guide plate, an area light source device, a display device, and manufacturing method for the light guide plate such that the occurrence of uneven luminance is suppressed. The light guide plate (12) is characterized in that the light guide plate has a light entrance surface (12a) through which light enters, a light exit surface (12c) intersecting with the light entrance surface (12a) and through which light is output, and an opposite surface (12b) facing the light entrance surface (12a), wherein the light entering through the light entrance surface (12a) is guided to the opposite surface (12b) side and output from the light exit surface (12c), and the refractive index Nx in a direction perpendicular to the light entrance surface (12a) is higher than the refractive index Ny in a direction parallel to the light exit surface (12c) and parallel to the light entrance surface (12a).
    Type: Grant
    Filed: April 16, 2018
    Date of Patent: November 29, 2022
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Kohei Komizo, Tetsuya Sadahiro, Hironori Hashiguchi, Koujiro Ohkawa
  • Publication number: 20210088710
    Abstract: Provided are a light guide plate, an area light source device, a display device, and manufacturing method for the light guide plate such that the occurrence of uneven luminance is suppressed. The light guide plate (12) is characterized in that the light guide plate has a light entrance surface (12a) through which light enters, a light exit surface (12c) intersecting with the light entrance surface (12a) and through which light is output, and an opposite surface (12b) facing the light entrance surface (12a), wherein the light entering through the light entrance surface (12a) is guided to the opposite surface (12b) side and output from the light exit surface (12c), and the refractive index Nx in a direction perpendicular to the light entrance surface (12a) is higher than the refractive index Ny in a direction parallel to the light exit surface (12c) and parallel to the light entrance surface (12a).
    Type: Application
    Filed: April 16, 2018
    Publication date: March 25, 2021
    Applicant: Dai Nippon Printing Co., Ltd.
    Inventors: Kohei KOMIZO, Tetsuya SADAHIRO, Hironori HASHIGUCHI, Koujiro OHKAWA
  • Patent number: 9285669
    Abstract: A reflection screen includes: a reflection layer provided on the back side and adapted to reflect light; and a surface shape layer provided on the reflection layer, at the image source side relative to the reflection screen, the surface shape layer having a plurality of unit optical shapes arrayed and deflecting image light toward the reflection layer side. The unit optical shape satisfies, in a section along the array direction of the unit optical shapes and orthogonal to a screen plane, the relationship of ?+2???>90°, where ? is an angle that a total reflection surface makes with a plane parallel to the screen plane, ? is an angle that an incidence surface makes with a normal direction to the screen plane, and ? is an angle that light incident on the incidence surface makes with the normal direction to the screen plane.
    Type: Grant
    Filed: November 26, 2014
    Date of Patent: March 15, 2016
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Tetsuya Sadahiro, Kazunobu Ogawa
  • Patent number: 9030736
    Abstract: A reflection screen includes: a reflection layer provided on the back side and adapted to reflect light; and a surface shape layer provided on the reflection layer, at the image source side relative to the reflection screen, the surface shape layer having a plurality of unit optical shapes arrayed and deflecting image light toward the reflection layer side. The unit optical shape satisfies, in a section along the array direction of the unit optical shapes and orthogonal to a screen plane, the relationship of ?+2???>90°, where ? is an angle that a total reflection surface makes with a plane parallel to the screen plane, ? is an angle that an incidence surface makes with a normal direction to the screen plane, and ? is an angle that light incident on the incidence surface makes with the normal direction to the screen plane.
    Type: Grant
    Filed: August 15, 2013
    Date of Patent: May 12, 2015
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Tetsuya Sadahiro, Kazunobu Ogawa
  • Publication number: 20150077849
    Abstract: A reflection screen includes: a reflection layer provided on the back side and adapted to reflect light; and a surface shape layer provided on the reflection layer, at the image source side relative to the reflection screen, the surface shape layer having a plurality of unit optical shapes arrayed and deflecting image light toward the reflection layer side. The unit optical shape satisfies, in a section along the array direction of the unit optical shapes and orthogonal to a screen plane, the relationship of ?+2???>90°, where ? is an angle that a total reflection surface makes with a plane parallel to the screen plane, ? is an angle that an incidence surface makes with a normal direction to the screen plane, and ? is an angle that light incident on the incidence surface makes with the normal direction to the screen plane.
    Type: Application
    Filed: November 26, 2014
    Publication date: March 19, 2015
    Inventors: Tetsuya SADAHIRO, Kazunobu OGAWA
  • Patent number: 8891169
    Abstract: Provided is an optical sheet hardly causing a change in color depending on the observation angle of an image, the optical sheet including a plurality of layers, at least one of the layers being an optical functional sheet layer including prisms arranged in parallel along a surface of the optical sheet such that light is transmittable; and light-absorbing portions arranged in parallel between the prisms in a way to absorb light, at least another one of the layers being a light diffusing material-containing layer with optical diffusing particles dispersed in a base material, and the optical sheet satisfying a relation of NdK <NdR and vdK <vdR, wherein NdK is a refractive index of the base material of the light diffusing material-containing layer, vdK is an Abbe number thereof, NdR is a refractive index of the optical diffusing particles and vdR is an Abbe number thereof.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: November 18, 2014
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Tsuyoshi Kashiwagi, Tetsuya Sadahiro, Hiroyuki Amemiya, Nobuhiko Ichikawa
  • Patent number: 8696187
    Abstract: An optical member includes a first optical sheet, and a second optical sheet disposed on the light exit side of the first optical sheet. The optical sheets each include a body portion, and unit shaped elements arranged side by side on the body portion. The ratio of the height of the unit shaped elements relative to the arrangement pitch of the unit shaped elements in the first optical sheet is smaller than that in the second optical sheet.
    Type: Grant
    Filed: March 24, 2010
    Date of Patent: April 15, 2014
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Masahiro Goto, Tetsuya Sadahiro
  • Publication number: 20140092471
    Abstract: A reflection screen includes: a reflection layer provided on the back side and adapted to reflect light; and a surface shape layer provided on the reflection layer, at the image source side relative to the reflection screen, the surface shape layer having a plurality of unit optical shapes arrayed and deflecting image light toward the reflection layer side. The unit optical shape satisfies, in a section along the array direction of the unit optical shapes and orthogonal to a screen plane, the relationship of ?+2???>90°, where ? is an angle that a total reflection surface makes with a plane parallel to the screen plane, ? is an angle that an incidence surface makes with a normal direction to the screen plane, and ? is an angle that light incident on the incidence surface makes with the normal direction to the screen plane.
    Type: Application
    Filed: August 15, 2013
    Publication date: April 3, 2014
    Applicant: Dai Nippon Printing Co., Ltd.
    Inventors: Tetsuya SADAHIRO, Kazunobu OGAWA
  • Patent number: 8634136
    Abstract: There is provided a screen that, as a screen suitable for an interactive board, can output video image light incident obliquely from the back surface side to a viewer side to display a reflection-free image and, at the same time, can realize easy handwriting on the screen surface on the viewer side. To this end, a transmission screen for an interactive board is provided that comprises at least a Fresnel lens sheet comprising a prism part on its incident light side, a light diffusing member provided on the Fresnel lens on its surface side remote from the prism part, and a hard coat layer provided on the outgoing light side of the light diffusing member.
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: January 21, 2014
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Kazunobu Ogawa, Takeshi Ogawa, Kenji Ohki, Tetsuya Sadahiro
  • Publication number: 20120020081
    Abstract: An optical member (28) includes a first optical sheet (30), and a second optical sheet (40) disposed on the light exit side of the first optical sheet (30). The optical sheets each include a body portion (32, 42), and unit shaped elements (35, 45) arranged side by side on the body portion. The ratio of the height of the unit shaped elements relative to the arrangement pitch of the unit shaped elements in the first optical sheet is smaller than that in the second optical sheet.
    Type: Application
    Filed: March 24, 2010
    Publication date: January 26, 2012
    Applicant: Dai Nippon Printing Co., Ltd.
    Inventors: Masahiro Goto, Tetsuya Sadahiro
  • Publication number: 20110216416
    Abstract: There is provided an optical sheet and a display device which hardly cause a change in color depending on the observation angle of an image. The optical sheet comprises a plurality of layers, at least one of the plurality of layers being an optical functional sheet layer which includes prisms arranged in parallel along a surface of the optical sheet in such a way that light is transmittable; and light-absorbing portions arranged in parallel between the prisms in such a way as to absorb light, at least another one of the layers being a light diffusing material-containing layer with optical diffusing particles dispersed in a sheet-shaped base material, and the optical sheet satisfying a relation of NdK<NdR and ?dK<?dR, wherein NdK is a refractive index of the base material of the light diffusing material-containing layer and ?dK is an Abbe number thereof, and NdR is a refractive index of the optical diffusing particles and ?dR is an Abbe number thereof.
    Type: Application
    Filed: September 17, 2009
    Publication date: September 8, 2011
    Inventors: Tsuyoshi Kashiwagi, Tetsuya Sadahiro, Hiroyuki Amemiya, Nobuhiko Ichikawa
  • Publication number: 20110122493
    Abstract: There is provided a screen that, as a screen suitable for an interactive board, can output video image light incident obliquely from the back surface side to a viewer side to display a reflection-free image and, at the same time, can realize easy handwriting on the screen surface on the viewer side. To this end, a transmission screen for an interactive board is provided that comprises at least a Fresnel lens sheet comprising a prism part on its incident light side, a light diffusing member provided on the Fresnel lens on its surface side remote from the prism part, and a hard coat layer provided on the outgoing light side of the light diffusing member.
    Type: Application
    Filed: March 25, 2010
    Publication date: May 26, 2011
    Applicant: Dai Nippon Printing Co., Ltd.
    Inventors: Kazunobu Ogawa, Takeshi Ogawa, Kenji Ohki, Tetsuya Sadahiro