Patents by Inventor Kenji Takashima

Kenji Takashima 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: 20150103406
    Abstract: This invention provides an optical member in which ripple is suppressed and a porous glass layer is formed on a base member and also provides a method for easily manufacturing the optical member. An optical member has a base member (1) and a porous glass layer (2) formed on the base member (1), in which a textured structure is formed on the interface contacting the porous glass layer (2) of the base member (1) and the height of the textured structure is 100 nm or more and equal to or lower than the thickness of the porous glass layer (2).
    Type: Application
    Filed: May 17, 2013
    Publication date: April 16, 2015
    Inventors: Kenji Takashima, Zuyi Zhang, Yoshinori Kotani, Akiko Takei, Akira Sugiyama, Naoyuki Koketsu
  • Patent number: 9003833
    Abstract: This invention provides a porous glass with a varied porous structure that shows an excellent optical performance. A method of manufacturing a porous glass comprising: a first step of forming a surface layer containing a boron compound and an alkali metal compound as main ingredients on a matrix glass containing a silicon oxide, a boron oxide and an alkali metal oxide; a second step of heat treatment the matrix glass and the surface layer for phase separation to form a phase-separated glass; and a third step of acid treatment the phase-separated glass to form the porous glass having pores.
    Type: Grant
    Filed: November 25, 2011
    Date of Patent: April 14, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinori Kotani, Zuyi Zhang, Akira Sugiyama, Kenji Takashima, Naoyuki Koketsu
  • Patent number: 8993107
    Abstract: The present invention provides a porous glass having excellent antireflection performance for visible light. A porous glass includes a porous layer which is mainly composed of silica and which has pores attributed to spinodal phase separation and pores attributed to binodal phase separation.
    Type: Grant
    Filed: August 25, 2011
    Date of Patent: March 31, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinori Kotani, Zuyi Zhang, Kenji Takashima, Akira Sugiyama
  • Patent number: 8908353
    Abstract: A laminated ceramic capacitor has multiple layered dielectric ceramic layers of a dielectric ceramic constituted by primary phase grains whose primary component is BaTiO3, secondary phase grains containing at least Re (Re represents at least one of Eu, Gd, Dy, Ho, Er, Yb, and Y), Ba, and Ti, and grain boundary phase containing at least one of B and Li or both; and internal electrodes which are made of Cu or Cu alloy. When a thickness of the dielectric ceramic layer is given by t, and when grain sizes at cumulative 20%, cumulative 50%, and cumulative 95% points of a cumulative count distribution of the primary phase grains are given by D20, D50, and D95, respectively, D20?D50×70%, D50?t/4, D95?t/2, and CV value ((standard deviation between D20 and D95)/D50)<40% are satisfied.
    Type: Grant
    Filed: September 26, 2011
    Date of Patent: December 9, 2014
    Assignee: Taiyo Yuden Co., Ltd.
    Inventors: Kenji Takashima, Shinsuke Takeoka
  • Publication number: 20140335346
    Abstract: To provide an optical member having a porous glass layer on a substrate and rarely causing ripples. The optical member has a porous glass layer on a substrate. The porous glass layer includes a first porous glass layer and a second porous glass layer in this order on the substrate. The first porous glass layer has a uniform porosity. The second porous glass layer has a higher uniform porosity than the first porous glass layer.
    Type: Application
    Filed: November 8, 2012
    Publication date: November 13, 2014
    Inventors: Akira Sugiyama, Zuyi Zhang, Yoshinori Kotani, Akiko Takei, Kenji Takashima, Naoyuki Koketsu
  • Publication number: 20140320728
    Abstract: The present invention provides an optical member including a porous glass layer on the base member, wherein a ripple is suppressed. The optical member includes the porous glass layer which is disposed on the base member and which has a thickness of 400 nm or more, wherein the porous glass layer includes at least a gradient region having a porosity increasing from the interface between the base member and the porous glass layer toward the surface of the porous glass layer, the porosity is continuous in the thickness direction from the base member to the surface of the porous glass layer, and a specific relational expression is satisfied.
    Type: Application
    Filed: November 6, 2012
    Publication date: October 30, 2014
    Inventors: Akira Sugiyama, Zuyi Zhang, Yoshinori Kotani, Akiko Takei, Kenji Takashima, Naoyuki Koketsu
  • Publication number: 20140313391
    Abstract: An imaging apparatus for imaging a subject image from a lens on an imaging element through an optical filter has a porous body having pores which three dimensionally communicate with each other at least at a side opposite to the imaging element of the optical filter.
    Type: Application
    Filed: July 1, 2014
    Publication date: October 23, 2014
    Inventors: Zuyi Zhang, Yoshinori Kotani, Akira Sugiyama, Kenji Takashima, Naoyuki Koketsu
  • Publication number: 20140305166
    Abstract: The present invention provides an optical member having a high transmittance, wherein a composition change of a phase-separable base material glass film is suppressed. A method for manufacturing an optical member provided with a porous glass film on the base member includes the steps of forming a glass powder film containing a glass powder on the base member, forming a phase-separable base material glass film on the base member by heating and fusing the glass powder film in an atmosphere having an oxygen concentration of more than 20%, forming a phase-separated glass film on the base member by heating the base material glass film, and forming a porous glass film on the base member by subjecting the phase-separated glass film to an etching treatment.
    Type: Application
    Filed: October 18, 2012
    Publication date: October 16, 2014
    Inventors: Naoyuki Koketsu, Zuyi Zhang, Yoshinori Kotani, Akiko Takei, Akira Sugiyama, Kenji Takashima
  • Publication number: 20140299573
    Abstract: The present invention provides a method for producing a porous glass layer easily, wherein a ripple is suppressed. A method for manufacturing an optical member provided with a porous glass layer on a base member includes the steps of forming an intermediate layer containing at least one of silicon, potassium, and aluminum on the base member, forming a phase-separable glass layer on the intermediate layer, forming a phase-separated glass layer on the base member by heating the intermediate layer and the phase-separable glass layer at a temperature higher than or equal to the glass transition temperature of the phase-separable glass layer, and forming a porous glass layer on the base member by subjecting the phase-separated glass layer to an etching treatment.
    Type: Application
    Filed: December 11, 2012
    Publication date: October 9, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kenji Takashima, Zuyi Zhang, Yoshinori Kotani, Akiko Takei, Akira Sugiyama, Naoyuki Koketsu
  • Publication number: 20140293114
    Abstract: The present invention provides an optical member including a porous glass film on a base member, wherein a ripple is suppressed. The optical member includes the base member and the porous glass film disposed on the base member, wherein the porosity increases in the direction from the base member toward the porous glass film in an interfacial region between the base member and the porous glass film and the porosity is continuous in the film thickness direction from the base member to the surface of the porous glass film in the optical member.
    Type: Application
    Filed: November 12, 2012
    Publication date: October 2, 2014
    Inventors: Naoyuki Koketsu, Zuyi Zhang, Yoshinori Kotani, Akiko Takei, Akira Sugiyama, Kenji Takashima
  • Patent number: 8804140
    Abstract: An imaging apparatus for imaging a subject image from a lens on an imaging element through an optical filter has a porous body having pores which three dimensionally communicate with each other at least at a side opposite to the imaging element of the optical filter.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: August 12, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Zuyi Zhang, Yoshinori Kotani, Akira Sugiyama, Kenji Takashima, Naoyuki Koketsu
  • Publication number: 20140178290
    Abstract: Provided is a lead-free dielectric ceramics having a low leakage current value, and a bismuth iron oxide powder as a raw material thereof. The bismuth iron oxide powder includes at least: (A) grains including a bismuth iron oxide having a perovskite-type crystal structure; (B) grains including a bismuth iron oxide having a crystal structure classified to a space group Pbam; and (C) grains including a bismuth iron oxide or a bismuth oxide having a crystal structure that is classified to a space group I23. The dielectric ceramics are made of bismuth iron oxide in which the bismuth iron oxide crystals having the crystal structure classified to the space group Pbam are distributed at a grain boundary of crystal grains of the bismuth iron oxide crystals having the perovskite-type crystal structure.
    Type: Application
    Filed: February 27, 2014
    Publication date: June 26, 2014
    Applicants: FUJI CHEMICAL CO., LTD., CANON KABUSHIKI KAISHA
    Inventors: Hisato Yabuta, Makoto Kubota, Mikio Shimada, Kenji Takashima, Fumio Uchida, Kenji Maeda, Chiemi Shimizu
  • Patent number: 8704429
    Abstract: Provided is a lead-free dielectric ceramics having a low leakage current value, and a bismuth iron oxide powder as a raw material thereof. The bismuth iron oxide powder includes at least: (A) grains including a bismuth iron oxide having a perovskite-type crystal structure; (B) grains including a bismuth iron oxide having a crystal structure classified to a space group Pbam; and (C) grains including a bismuth iron oxide or a bismuth oxide having a crystal structure that is classified to a space group I23. The dielectric ceramics are made of bismuth iron oxide in which the bismuth iron oxide crystals having the crystal structure classified to the space group Pbam are distributed at a grain boundary of crystal grains of the bismuth iron oxide crystals having the perovskite-type crystal structure.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: April 22, 2014
    Assignees: Canon Kabushiki Kaisha, Fuji Chemical Co., Ltd.
    Inventors: Hisato Yabuta, Makoto Kubota, Mikio Shimada, Kenji Takashima, Fumio Uchida, Kenji Maeda, Chiemi Shimizu
  • Publication number: 20140009864
    Abstract: A laminated ceramic capacitor has multiple layered dielectric ceramic layers of a dielectric ceramic constituted by primary phase grains whose primary component is BaTiO3, secondary phase grains containing at least Re (Re represents at least one of Eu, Gd, Dy, Ho, Er, Yb, and Y), Ba, and Ti, and grain boundary phase containing at least one of B and Li or both; and internal electrodes which are made of Cu or Cu alloy. When a thickness of the dielectric ceramic layer is given by t, and when grain sizes at cumulative 20%, cumulative 50%, and cumulative 95% points of a cumulative count distribution of the primary phase grains are given by D20, D50, and D95, respectively, D20?D50×70%, D50?t/4, D95?t/2, and CV value ((standard deviation between D20 and D95)/D50)<40% are satisfied.
    Type: Application
    Filed: September 26, 2011
    Publication date: January 9, 2014
    Applicant: TAIYO YUDEN CO., LTD.
    Inventors: Kenji Takashima, Shinsuke Takeoka
  • Publication number: 20130333419
    Abstract: A method for manufacturing a porous glass includes: forming a phase-separated glass by heating at a temperature in a range of 300 to 500 degrees Celsius for 3 to 50 hours for phase separation of a glass body in which the concentration of SiO2 is 50 to 70 percent by weight, the concentration of B2O3 is 15 to 40 percent by weight, the concentration of Li2O is 1.0 to 8.0 percent by weight, the concentration of Na2O is 2.0 to 8.0 percent by weight, the concentration of K2O is 0.3 to 5.0 percent by weight, the total concentration of Li2O, Na2O, and K2O is 3.5 to 15 percent by weight, and the ratio of the concentration of K2O to the total concentration of Li2O, Na2O, and K2O is 0.10 to 0.30; and forming a porous glass by etching the phase-separated glass.
    Type: Application
    Filed: February 20, 2012
    Publication date: December 19, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Naoyuki Koketsu, Zuyi Zhang, Yoshinori Kotani, Akira Sugiyama, Kenji Takashima
  • Patent number: 8547001
    Abstract: To provide a piezoelectric ceramic containing BiFeO3 having a {110} plane orientation in a pseudo-cubic form, which is suited for the domain engineering, the piezoelectric ceramic includes a perovskite-type metal oxide represented by the following general formula (1), and has a {110} plane orientation in a pseudo-cubic form: xBiFeO3-(1?x)ABO3??General Formula (1) where A and B each represent one kind or more of metal ions; A represents a metal ion having a valence of 1, 2 or 3; and B represents a metal ion having a valence of 3, 4, or 5, provided that x is within a range of 0.3?x?1.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: October 1, 2013
    Assignees: Canon Kabushiki Kaisha, University of Yamanashi
    Inventors: Hiroshi Saito, Takanori Matsuda, Kenji Takashima, Nobuhiro Kumada
  • Publication number: 20130233018
    Abstract: To provide a method of manufacturing a porous glass in which the porosity decreases as a function of the distance from the surface in the direction of depth. A method of manufacturing a porous glass includes a step of bringing one or more than one ion species selected from silver ion, potassium ion and lithium ion into contact with a matrix glass containing borosilicate glass as main ingredient and heating the matrix glass to form a glass body having an ion concentration distribution with a concentration of the one or more than one ion species decreasing as a function of a distance from a surface in a direction of depth, a step of heating and phase-separating the glass body to form a phase-separated glass, and a step of etching the phase-separated glass to form a porous glass having a porosity decreasing as the function of the distance from the surface in the direction of depth.
    Type: Application
    Filed: November 25, 2011
    Publication date: September 12, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kenji Takashima, Zuyi Zhang, Yoshinori Kotani, Akira Sugiyama, Naoyuki Koketsu
  • Publication number: 20130224494
    Abstract: This invention provides a porous glass with a varied porous structure that shows an excellent optical performance. A method of manufacturing a porous glass comprising: a first step of forming a surface layer containing a boron compound and an alkali metal compound as main ingredients on a matrix glass containing a silicon oxide, a boron oxide and an alkali metal oxide; a second step of heat treatment the matrix glass and the surface layer for phase separation to form a phase-separated glass; and a third step of acid treatment the phase-separated glass to form the porous glass having pores.
    Type: Application
    Filed: November 25, 2011
    Publication date: August 29, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yoshinori Kotani, Zuyi Zhang, Akira Sugiyama, Kenji Takashima, Naoyuki Koketsu
  • Publication number: 20130216775
    Abstract: Provided is an optical member having high strength, low reflection, and a high transmittance. The optical member includes: a transparent substrate; and a porous glass layer having a spinodal-type porous structure disposed on the transparent substrate, in which at least one of the average pore diameter of a pore formed in the porous glass layer and the average skeleton diameter of a skeleton of the porous glass layer is set so that the optical member has a transmittance of 50% or more in the wavelength region of 450 nm or more and 650 nm or less.
    Type: Application
    Filed: November 1, 2011
    Publication date: August 22, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Akira Sugiyama, Zuyi Zhang, Yoshinori Kotani, Kenji Takashima, Naoyuki Koketsu
  • Publication number: 20130192306
    Abstract: There is provided a method for producing a porous glass having high porosity and nanosized pores even at a deeper portion in the glass. A method for producing a porous glass includes the steps of preparing a glass body containing boron, subjecting the glass body to heat treatment for phase separation, and bringing the phase-separated glass body into contact with a boron-containing solution having a boron concentration of 5 to 140 ppm.
    Type: Application
    Filed: September 16, 2011
    Publication date: August 1, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Akira Sugiyama, Zuyi Zhang, Yoshinori Kotani, Kenji Takashima