Patents by Inventor Nao Murakami

Nao Murakami 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: 20100141873
    Abstract: It is an object of the present invention to provide a liquid crystal display panel having a high contrast ratio in a front direction. A liquid crystal panel according to an embodiment of the present invention includes: a liquid crystal cell; a first polarizing plate placed on one side of the liquid crystal cell; a second polarizing plate placed on the other side of the liquid crystal cell; and a retardation layer placed between the liquid crystal cell and the second polarizing plate. A refractive index ellipsoid of the retardation layer exhibits a relationship of n?ny>nz; and a light transmittance (T2) of the second polarizing plate is larger than a light transmittance (T1) of the first polarizing plate.
    Type: Application
    Filed: May 11, 2007
    Publication date: June 10, 2010
    Applicant: NITTO DENKO CORPORATION
    Inventors: Naotaka Kinjo, Kentarou Yoshida, Takashi Shimizu, Shinobu Nagano, Nao Murakami, Masaki Hayashi
  • Publication number: 20100110347
    Abstract: There is provided a liquid crystal panel exhibiting a high contrast ratio and a liquid crystal display apparatus including the liquid crystal panel. The liquid crystal panel of the present invention includes a first polarizer, a first optical compensation layer, a liquid crystal cell, a second optical compensation layer, and a second polarizer in the stated order from a viewer side. The first optical compensation layer and the second optical compensation layer have a refractive index profile of nx>ny>nz, and a light transmittance (T2) of the second polarizer is larger than a light transmittance (T1) of the first polarizer.
    Type: Application
    Filed: April 23, 2008
    Publication date: May 6, 2010
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takeharu Kitagawa, Kentarou Takeda, Nao Murakami, Hiroyuki Yoshimi
  • Patent number: 7671949
    Abstract: A polarizing plate with optical compensation function, including a polarizing layer and an optically compensating layer, wherein the optically compensating layer includes an optically compensating A-layer including a stretched polymer film and an optically compensating B-layer including a cholesteric liquid crystal layer.
    Type: Grant
    Filed: February 18, 2003
    Date of Patent: March 2, 2010
    Assignee: Nitto Denko Corporation
    Inventors: Shinichi Sasaki, Takashi Yamaoka, Nao Murakami, Hiroyuki Yoshimi
  • Patent number: 7639329
    Abstract: The liquid crystal panel according to an embodiment of the present invention includes, in the stated order from a viewer side: a first polarizer; a first optical compensation layer; a liquid crystal cell; a second optical compensation layer; and a second polarizer, wherein: the first optical compensation layer has an absolute value of a photoelastic coefficient of 40×10?12 (m2/N) or less, has an in-plane retardation ?nd of 90 nm to 200 nm, has relationships of the following Expressions (1) and (2), and functions as a protective layer on a liquid crystal cell side of the first polarizer; and the second optical compensation layer has relationships of the following Expressions (3) and (4), ?nd(380)=?nd(550)=?nd(780)??(1) nx>ny>nz??(2) Rth(380)>Rth(550)>Rth(780)??(3) nx=ny>nz??(4).
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: December 29, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Kentarou Takeda, Takeharu Kitagawa, Daisuke Hayashi, Hideki Ishida, Nao Murakami, Junichi Nagase
  • Publication number: 20090316086
    Abstract: The liquid crystal panel according to an embodiment of the present invention includes a liquid crystal cell, a first polarizing plate placed on one side of the liquid crystal cell, a second polarizing plate and a third polarizing plate placed on the other side of the liquid crystal cell in an order starting from a side of the liquid crystal cell, and a retardation plate (A) placed between the liquid crystal cell and the second polarizing plate, wherein a refractive index ellipsoid of the retardation plate (A) has a relationship of nx?ny>nz, a difference (?T2?1=T2?T1) between a transmittance (T2) of the second polarizing plate and a transmittance (T1) of the first polarizing plate is larger than 0%, a difference (?T3?2=T3?T2) between a transmittance (T3) of the third polarizing plate and a transmittance (T2) of the second polarizing plate is 4.0% to 7.5%, and the third polarizing plate is a linearly polarized light separation type reflective polarizing plate.
    Type: Application
    Filed: June 23, 2009
    Publication date: December 24, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takaaki Ishii, Masatsugu Higashi, Nao Murakami
  • Patent number: 7630038
    Abstract: There are provided a liquid crystal panel and a liquid crystal display apparatus each having an excellent screen contrast, a small color shift, and small display unevenness. The liquid crystal panel includes a liquid crystal cell; a first polarizer placed on one side of the liquid crystal cell; a second polarizer placed on the other side of the liquid crystal cell; and at least two optical compensation layers including a first optical compensation layer and a second optical compensation layer placed between the first polarizer and the second polarizer.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: December 8, 2009
    Assignee: Nitto Denko Cororation
    Inventors: Kentarou Takeda, Nao Murakami, Junichi Nagase, Toshiyuki Iida, Kentarou Yoshida
  • Publication number: 20090279031
    Abstract: A liquid crystal display apparatus is provided, in which excellent viewing angle compensation is conducted, and which is highly excellent in a contrast in an oblique direction and can be reduced in thickness. A liquid crystal panel of the present invention includes a first polarizer, a first optical compensation layer, a liquid crystal cell, a second optical compensation layer, and a second polarizer in the stated order. Each of the first optical compensation layer and the second optical compensation layer contains at least one polymer selected from the group consisting of polyimide, polyamide, polyester, polyetherketone, polyamideimide, and polyesterimide, and have a refractive index profile of nx>ny>nz.
    Type: Application
    Filed: August 9, 2006
    Publication date: November 12, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takeharu Kitagawa, Kentarou Takeda, Yoshiyuki Kiya, Nao Murakami, Shuusaku Nakano
  • Patent number: 7586571
    Abstract: The present invention provides a composite birefringent member including a first birefringent layer and a second birefringent layer. The second birefringent layer is formed on at least one surface of the first birefringent layer. In the wavelength range from 400 to 800 nm, a value of ?ndx/?nd550 and a value of Rthx/Rth550 of the composite birefringent member as a whole are different from each other. The composite birefringent member satisfies a requirement that the second birefringent layer is formed of a polymer such as polyamide and/or a requirement that ?nd and Rth of the composite birefringent member satisfy formulae (I) and (II) below. As a result, the composite birefringent member allows a liquid crystal display to achieve a wide viewing angle, compensates birefringence of a liquid crystal cell, and does not cause display coloring of the liquid crystal display. ?nd400/?nd550<1 ??(I) Rth400/Rth550>1 ??(II).
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: September 8, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Hiroyuki Yoshimi, Yuuichi Nishikouji, Nao Murakami
  • Publication number: 20090207347
    Abstract: There is provided a liquid crystal display panel having a high contrast ratio in a front direction. A liquid crystal panel of the present invention includes: a liquid crystal cell; a first polarizing plate placed on one side of the liquid crystal cell; and a second polarizing plate placed on another side of the liquid crystal cell. A transmittance (T1) of the first polarizing plate is higher than a transmittance (T2) of the second polarizing plate. Preferably, a difference (?T=T1?T2) between the transmittance (T1) of the first polarizing plate and the transmittance (T2) of the second polarizing plate is 0.1% to 6.0%.
    Type: Application
    Filed: June 22, 2007
    Publication date: August 20, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takashi Shimizu, Kentarou Yoshida, Naotaka Kinjo, Nao Murakami
  • Patent number: 7538841
    Abstract: The present invention can provide an optical film suitable for a liquid crystal display apparatus providing colorless neutral display in all azimuth angle directions, a liquid crystal panel employing the optical film, and a liquid crystal display apparatus employing the liquid crystal panel. The optical film of the present invention includes a first transparent protective film, a polarizer, a second transparent protective film, and a birefringent layer having a relationship of nx>ny=nz and positive uniaxial property in the stated order, in which the second transparent protective film has a thickness direction retardation (Rth) represented by the formula Rth=(nx?nz)×d of 10 nm or less.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: May 26, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Nao Murakami, Kentarou Takeda, Yoshiyuki Kiya, Hiroyuki Yoshimi
  • Patent number: 7535531
    Abstract: The present invention provides a birefringent optical film that allows a liquid crystal display to achieve excellent contrast and a wide viewing angle and does not cause coloring of the liquid crystal display. The birefringent optical film includes at least one birefringent A-layer having a property satisfying nya?nza>nxa or nza>nya>nza and at least one birefringent B-layer having a property satisfying nxb?nyb>nzb.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: May 19, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Yuuichi Nishikouji, Hiroyuki Yoshimi, Nao Murakami
  • Publication number: 20090091682
    Abstract: A liquid crystal panel according to the present invention includes a backlight portion emitting light having a brightness distribution in a horizontally oblong oval shape assuming that a longitudinal direction of a panel is a horizontal direction; a first polarizer; a liquid crystal cell; an optical compensation layer having a refractive index profile of nx>ny>nz; and a second polarizer, in this order from a backlight side. According to the present invention, a liquid crystal panel having remarkably excellent contrast in an oblique direction, small light leakage in a black display and a small color shift is provided.
    Type: Application
    Filed: April 20, 2006
    Publication date: April 9, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Nao Murakami, Hiroyuki Yoshimi
  • Patent number: 7494689
    Abstract: It is an object of the present invention to provide a method for manufacturing a birefringent film that can reduce the amount of a remaining solvent in the birefringent film without degrading appearance uniformity or an alignment in its thickness direction. The method of the present invention for manufacturing an optical film includes the steps of: coating a base with a polymer solution obtained by dissolving a polyimide-containing polymer in a solvent so as to form a coating film; and drying the coating film so as to form a birefringent film, in which the drying step includes at least two stages of drying processes. The drying step preferably include two stages of the drying processes, and a temperature in the former stage of the drying process is preferably lower than a temperature in the latter stage of the drying process. If adding a step of providing the birefringent film with an anisotropy of a refractive index in an in-plane direction, a birefringent film with an optical biaxiality can be manufactured.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: February 24, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Masaki Hayashi, Nao Murakami, Yuuichi Nishikouji, Hiroyuki Yoshimi
  • Publication number: 20090046228
    Abstract: There are provided a liquid crystal panel and a liquid crystal display apparatus each having an excellent screen contrast, a small color shift, and small display unevenness. The liquid crystal panel includes a liquid crystal cell; a first polarizer placed on one side of the liquid crystal cell; a second polarizer placed on the other side of the liquid crystal cell; and at least two optical compensation layers including a first optical compensation layer and a second optical compensation layer placed between the first polarizer and the second polarizer.
    Type: Application
    Filed: October 20, 2006
    Publication date: February 19, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kentarou Takeda, Nao Murakami, Junichi Nagase, Toshiyuki Iida, Kentarou Yoshida
  • Patent number: 7462381
    Abstract: A method of manufacturing a birefringent film is provided, by which a birefringent film including a liquid crystal compound birefringent layer and another birefringent layer can be manufactured so as to have a reduced thickness in a reduced number of process steps. In the manufacturing method, a non-liquid crystal polymer birefringent layer that has been subjected to an aligning treatment is used as an alignment layer for a liquid crystal compound. According to the manufacturing method, the process step of separately preparing an alignment layer and the need for the additional alignment layer can be eliminated, thereby allowing the total thickness of the birefringent film to be reduced.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: December 9, 2008
    Assignee: Nitto Denko Corporation
    Inventors: Hiroyuki Yoshimi, Yuuichi Nishikouji, Nao Murakami, Masaki Hayashi
  • Publication number: 20080273153
    Abstract: The liquid crystal panel according to an embodiment of the present invention includes, in the stated order from a viewer side: a first polarizer; a first optical compensation layer; a liquid crystal cell; a second optical compensation layer; and a second polarizer, wherein: the first optical compensation layer has an absolute value of a photoelastic coefficient of 40×10?12 (m2/N) or less, has an in-plane retardation ?nd of 90 nm to 200 nm, has relationships of the following Expressions (1) and (2), and functions as a protective layer on a liquid crystal cell side of the first polarizer; and the second optical compensation layer has relationships of the following Expressions (3) and (4), ?nd(380)=?nd(550)=?nd(780) ??(1) nx>ny>nz ??(2) Rth(380)>Rth(550)>Rth(780) ??(3) nx=ny>nz.
    Type: Application
    Filed: May 1, 2008
    Publication date: November 6, 2008
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kentarou TAKEDA, Takeharu KITAGAWA, Daisuke HAYASHI, Hideki ISHIDA, Nao MURAKAMI, Junichi NAGASE
  • Patent number: 7428029
    Abstract: The present invention relates to an optical film that is excellent in optical properties and can be produced at low cost. In the optical film formed by laminating a transparent polymer film layer and a birefringent layer of a non-liquid crystalline polymer, the birefringent layer satisfies a condition represented by nx?ny>nz and the in-plane retardation of the transparent polymer film layer is 50 nm or less. In the above formula, nx, ny and nz are the refraction indices in the X-, Y- and Z-axes directions of the birefringent layer, respectively. The X-axis direction is the axial direction in which the refraction index shows a maximum value in the in-plane direction of the birefringent layer, the Y-axis direction is the axial direction perpendicular to the X-axis direction in the plane, and the Z-axis direction is the thickness direction perpendicular to the X- and Y-axes directions.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: September 23, 2008
    Assignee: Nitto Denko Corporation
    Inventors: Nao Murakami, Hiroyuki Yoshimi, Yuuichi Nishikouji, Masaki Hayashi
  • Publication number: 20080111960
    Abstract: There are provided a liquid crystal panel and a liquid crystal display apparatus each having significantly improved color shift. The liquid crystal panel includes a backlight part emitting polarized light, an optical compensation layer, a first polarizer, a liquid crystal cell, and a second polarizer in the stated order from a backlight side.
    Type: Application
    Filed: December 19, 2005
    Publication date: May 15, 2008
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kentarou Yoshida, Nao Murakami, Hiroyuki Yoshimi, Yoshiyuki Kiya
  • Publication number: 20080018007
    Abstract: There is provided a polarizing plate including a polyimide layer on at least one side of a polarizer, the polarizing plate having excellent durability causing no peeling or floating of each film to be formed even in a high temperature and high humidity environment. The polarizing plate of the present invention includes a polarizer and a protective film attached to at least one side of the polarizer through an adhesive layer, in which: the protective film is a laminate film including a transparent film layer and a polyimide layer; and the polarizer and the protective film are attached together such that the polyimide layer opposes the polarizer.
    Type: Application
    Filed: September 20, 2007
    Publication date: January 24, 2008
    Applicant: NITTO DENKO CORPORATION
    Inventors: Junichi NAGASE, Nao MURAKAMI
  • Publication number: 20070273816
    Abstract: To provide a liquid crystal panel suitable for a liquid crystal display apparatus and capable of providing colorless neutral displays in all directions, and a liquid crystal display apparatus using the liquid crystal panel, the liquid crystal panel of the present invention includes: a liquid crystal cell; a first polarizer arranged on one side of the liquid crystal cell; a first birefringent layer arranged between the liquid crystal cell and the first polarizer; a second polarizer arranged on another side of the liquid crystal cell; and a second birefringent layer arranged between the liquid crystal cell and the second polarizer; in which: the first birefringent layer has a relationship of 1<Nz?2 where an Nz coefficient is defined by Nz=(nx-nz)/(nx-ny); and the second birefringent layer has a refractive index profile of nx=ny>nz.
    Type: Application
    Filed: May 21, 2007
    Publication date: November 29, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takeharu Kitagawa, Kentarou Takeda, Hiroyuki Yoshimi, Nao Murakami