Patents by Inventor Kazutaka Hara

Kazutaka Hara 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: 20070064168
    Abstract: An optical element comprising: a polarizing element (A), separating incident light into polarization to then emit light, and made of a cholesteric liquid crystal, wherein the polarizing element (A) has a distortion rate with respect to emitting light to incident light in the normal direction of 0.5 or more and a distortion rate with respect to emitting light to incident light at an angle inclined from the normal direction by 60 degrees or more of 0.
    Type: Application
    Filed: August 24, 2004
    Publication date: March 22, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Miki Shiraogawa, Kentarou Takeda, Kazutaka Hara, Naoki Takahashi
  • Publication number: 20070014127
    Abstract: A light source comprising sidelight type backlight light guide plate (L), wherein a transmittance angle dependent layer (T1) which transmits normally incident light and reflects obliquely incident light is disposed on one surface of the sidelight type backlight light guide plate (L), and a reflection plate (R) having a repetitive slope structure is disposed on the other surface of the sidelight type backlight light guide plate (L). The invention light source is less in absorption loss due to repetition of light reflection and the like.
    Type: Application
    Filed: August 20, 2004
    Publication date: January 18, 2007
    Applicant: Nitto Denko Corporation
    Inventors: Kazutaka Hara, Naoki Takahashi, Kentarou Takeda, Miki Shiraogawa
  • Publication number: 20070008460
    Abstract: An optical element of the invention comprises at least two laminated circular-polarization-type-reflection polarizers (a) whose wavelength bands for selective reflection of polarized light overlap one another, wherein the at least two circular-polarization-type-reflection polarizers (a) each have a side capable of selectively reflecting a relatively short wavelength in the wavelength bands for selective reflection, and the sides of said at least two circular-polarization-type-reflection polarizers (a) capable of selectively reflecting the relatively short wavelength are arranged opposite to each other. The optical element condenses or collimates incident light from a light source and can control transmission of light at large incident angles relative to the normal direction, increase front brightness and reduce coloration.
    Type: Application
    Filed: April 15, 2004
    Publication date: January 11, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kentarou Takeda, Kazutaka Hara, Naoki Takahashi
  • Publication number: 20060262401
    Abstract: An optical element of the invention comprises at least two laminated layers of at least one kind of reflective polarizer (a); and at least one layer of at least one kind of retardation layer (b) for changing polarization properties laminated between the reflective polarizers (a), the combination of the layers being designed so as to provide a incident-light transmittance depending on an incident angle of an incident light and designed such that a shielded light is not absorbed but reflected, wherein at least one layer of the reflective polarizer (a) is a circular polarization type reflective polarizer (a1) capable of transmitting a certain circularly polarized light and selectively reflecting an oppositely circularly polarized light; at least one layer of the reflective polarizer (a) is a linear polarization type reflective polarizer (a2) capable of transmitting one of perpendicular linearly polarized lights and selectively reflecting the other of the perpendicular linearly polarized lights; and the retardati
    Type: Application
    Filed: March 19, 2004
    Publication date: November 23, 2006
    Applicant: NITTO DENKO CORPORATION
    Inventors: Naoki Takahashi, Kantarou Takeda, Kazutaka Hara, Miki Shiraogawa
  • Publication number: 20060238867
    Abstract: An optical element of the invention comprises at least three laminated circular-polarization-type-reflection polarizers (a) whose wavelength bands for selective reflection of polarized light overlap one another; a layer (b1) which is placed between at least a pair of the circular-polarization-type-reflection polarizers (a) and has a front retardation of substantially zero (in the normal direction) and a retardation of at least ?/8 with respect to incident light inclined by at least 30° relative to the normal direction; and a layer (b2) which is placed between at least another pair of the circular-polarization-type-reflection polarizers (a) and has a front retardation of substantially zero (in the normal direction) and a retardation of at most ?/2 with respect to incident light inclined by 60° relative to the normal direction.
    Type: Application
    Filed: April 15, 2004
    Publication date: October 26, 2006
    Applicant: Nitto Denko Corporation
    Inventors: Kentarou Takeda, Naoki Takahashi, Kazutaka Hara, Takahiro Fukuoka
  • Publication number: 20060209238
    Abstract: A cholesteric liquid crystal film of the invention consist of a single layer, which is a cholesteric liquid crystal film, formed by applying a liquid crystal mixture containing a polymerizable mesogen compound (A) and a polymerizable chiral agent (B) to an alignment substrate, and applying ultraviolet irradiation to the mixture, wherein a cholesteric liquid crystal film has at least two independent selective reflection wavelength bands. The cholesteric liquid crystal film can be prepared by a simple and easy procedure.
    Type: Application
    Filed: April 15, 2004
    Publication date: September 21, 2006
    Inventors: Miki Shiraogawa, Kazutaka Hara, Takahiro Fukuoka
  • Publication number: 20060127605
    Abstract: A broad band cholesteric liquid crystal film of the present invention is a cholesteric liquid crystal film obtained by coating a liquid crystal mixture containing a polymerizable mesogen compound (a), a polymerizable chiral agent (b) and a photoisomerizable material (c) on a substrate to ultraviolet polymerize a coat of the liquid crystal mixture, and has a reflection bandwidth of 200 nm or more. A broad band cholesteric liquid crystal film of the present invention has a broad reflection band, is of a thin type and can be manufactured in less of manufacturing steps.
    Type: Application
    Filed: January 8, 2004
    Publication date: June 15, 2006
    Applicant: Nitto Denko Corporation
    Inventors: Kentarou Takeda, Kazutaka Hara, Naoki Takahashi, Takahiro Fukuoka
  • Publication number: 20060119783
    Abstract: A broad band cholesteric liquid crystal film of the present invention comprises a cholesteric liquid crystal film obtained by polymerizing a liquid crystal mixture containing a polymerizable mesogen compound (a), a polymerizable chiral agent (b) and a photopolymerization initiator (c) between two substrates with ultraviolet light, and has a reflection bandwidth of 200 nm or more. The broad band cholesteric liquid crystal film of the present invention has a broad reflection band and is excellent in durability.
    Type: Application
    Filed: January 8, 2004
    Publication date: June 8, 2006
    Applicant: Nitto Denko Corporation
    Inventors: Takahiro Fukuoka, Naoki Takahashi, Kazutaka Hara
  • Patent number: 7046320
    Abstract: An optical element 11 includes a bandpass filter made of a lamination of thin films respectively having different refraction factors so as to selectively allow light emitted from a backlight 6 to pass therethrough, and a polarizer 3, a quarter-wavelength plate 2 located between the bandpass filter 6 and the polarizer 3 so as to prevent light incident from the side of the polarizer 3 from being reflected by the bandpass filter 1 and then emitted from the side of the polarizer 3.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: May 16, 2006
    Assignee: Nitto Denko Corporation
    Inventor: Kazutaka Hara
  • Patent number: 6965418
    Abstract: A polarizer is bonded and laminated on a semi-transmitting reflective plate in which an antistatic layer of 10×1010 ohm or less in surface resistance is formed on the back surface of a light-transmitting high-molecular substrate having laminated thereon a semi-transmitting reflective layer composed of a light-transmitting deposited metal film or metal thin film, to thereby form a semi-transmitting polarizer.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: November 15, 2005
    Assignee: Nitto Denko Corporation
    Inventor: Kazutaka Hara
  • Publication number: 20050206804
    Abstract: A liquid crystal display device includes a backlight 1, a collimating element for collimating incoming light from the backlight and transmitting the collimated light, a liquid crystal cell for allowing the light coming from the collimating element to pass therethrough, and a viewing angle widening element 4 for widening the viewing angle by diffusing the light transmitted through the liquid crystal cell, in which the collimating element does not have a periodic pattern structure that allows Moire fringes or interference patterns seen in optical observation from a display side to be formed relative to a periodic pattern structure of another optical member of the liquid crystal display device.
    Type: Application
    Filed: March 13, 2003
    Publication date: September 22, 2005
    Inventor: Kazutaka Hara
  • Publication number: 20050200776
    Abstract: A viewing angle magnification liquid crystal display of this invention comprising: at least a backlight system containing a polarization element (A) obtained by disposing a retardation layer (b) between at least two layers, included in a reflection polarizer (a), and having respective selective reflection wavelength bands of polarized light superimposed on each other to conduct collimation for a diffusion light source; a liquid crystal cell transmitting collimated lights; a polarizing plate disposed on both sides of the liquid crystal cell; and a viewing angle magnifying layer disposed on the viewer side of the liquid crystal cell to diffuse transmitted light. The liquid crystal display can realize a thin type and have a wide viewing angle.
    Type: Application
    Filed: April 18, 2003
    Publication date: September 15, 2005
    Inventors: Kazutaka Hara, Naoki Takahashi, Minoru Miyatake
  • Patent number: 6942906
    Abstract: A resin sheet containing dispersed particles which is thin and lightweight, and has excellent mechanical strength and light-diffusing properties. The resin sheets may be used in liquid crystal displays. A resin sheet having a hard coat layer, an epoxy resin layer containing 100 parts by weight of the resin to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter from 0.2 to 100 ?m, and a thin metal layer as a reflecting layer, wherein the diffuser localizes so as to have a concentration distribution in the direction of the thickness of the epoxy resin layer. A resin sheet having dispersed particles which is obtained by superposing a reflecting layer, an inorganic gas barrier layer, or a color filter layer thereon. A process for producing the resin sheet having a color filter layer.
    Type: Grant
    Filed: November 6, 2003
    Date of Patent: September 13, 2005
    Assignee: Nitto Denko Corporation
    Inventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano
  • Patent number: 6936313
    Abstract: A resin sheet containing dispersed particles which is thin, lightweight, and has excellent mechanical strength and light-diffusing properties. The resin sheets may be used in liquid crystal displays. A resin sheet having a hard coat layer, an epoxy resin layer containing 100 parts by weight of the resin to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter from 0.2 to 100 ?m, and a thin metal layer as a reflecting layer, wherein the diffuser localizes so as to have a concentration distribution in the direction of the thickness of the epoxy resin layer. A resin sheet having dispersed particles which is obtained by superposing a reflecting layer, an inorganic gas barrier layer, or a color filter layer thereon. A process for producing the resin sheet having a color filter layer.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: August 30, 2005
    Assignee: Nitto Denko Corporation
    Inventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano
  • Publication number: 20050185112
    Abstract: A backlight used for a liquid crystal display device is characterized by including a bandpass filter that selectively allows blue light having a center wavelength of 400-440 nm, green light having a center wavelength of 520-530 nm and red light having a center wavelength of 620-640 nm, respectively, to pass therethrough, and a light source that emits at least light of the wavelength ranges towards the bandpass filter.
    Type: Application
    Filed: March 13, 2003
    Publication date: August 25, 2005
    Applicant: NITTO DENKO CORPORATION
    Inventor: Kazutaka Hara
  • Publication number: 20050180017
    Abstract: A light condensing system of this invention comprising: a backlight system having a light source and a first light condensing section (X) capable of condensing emitted light from the light source within ±60° of the front direction; and a light condensing film with no patterned structure as a second light condensing element (Y). The light condensing system effectively shield light passing-through in an oblique direction to thereby suppress uncomfortable coloring, present a good display, realize cost reduction.
    Type: Application
    Filed: April 18, 2003
    Publication date: August 18, 2005
    Inventors: Kazutaka Hara, Naoki Takahashi, Minoru Miyatake
  • Publication number: 20050151896
    Abstract: A polarization component, capable of efficiently reflecting an obliquely transmitted light beam toward a light source without degrading the transmission-polarization property of a perpendicular incident light beam, is provided. A C-plate having an oblique retardation of at least ?/8 with respect to a light beam inclined by at least 30° is disposed between at least two reflective circular polarizer layers whose selective reflection wavelength bands of polarized light overlapping each other. A combination of a reflective linear polarizer and a quarter wavelength plate may be used instead of the reflective circular polarizer. Alternatively, a combination of two reflective linear polarizer layers and two quarter wavelength plate layers (Nz?2) disposed therebetween can provide a similar effect. Further, a combination of two reflective linear polarizer layers and a half wavelength plate (Nz?1.5) disposed therebetween may be used.
    Type: Application
    Filed: April 17, 2003
    Publication date: July 14, 2005
    Inventors: Kazutaka Hara, Minoru Miyatake
  • Publication number: 20050088740
    Abstract: A rotatory polarization plate capable of extracting an emission polarized light from an incident polarized light and rotating an azimuth angle of an polarization axis of the incident polarized light, wherein a rotatory polarization angle of the azimuth angle is changed by an incidence angle of the incident polarized light, is useful for an optical element capable of condensing and collimating incident light from a light source in a specific direction.
    Type: Application
    Filed: October 21, 2004
    Publication date: April 28, 2005
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kentarou Takeda, Kazutaka Hara, Naoki Takahashi, Miki Shiraogawa
  • Patent number: 6876414
    Abstract: A semi-transmissible reflection layer is formed on a light-transmissible polymer substrate uniaxially drawn to have uniaxial orientation characteristic to thereby form a semi-transmissible reflector.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: April 5, 2005
    Assignee: Nitto Denko Corporation
    Inventors: Kazutaka Hara, Takafumi Sakuramoto, Minoru Miyatake, Tatsuya Osuka
  • Publication number: 20040121087
    Abstract: A resin sheet which has abase layer containing particles dispersed therein, is thin and lightweight, and has excellent mechanical strength and light-diffusing properties; a resin sheet containing dispersed particles which is obtained by superposing a reflecting layer or an inorganic gas barrier layer on that resin sheet; a resin sheet containing dispersed particles which is obtained by superposing a color filter layer on that resin sheet; processes for producing the resin sheet having a color filer layer; and liquid crystal displays employing those resin sheets. One of those resin sheets has a hard coat layer, an epoxy resin layer containing, per 100 parts by weight of the resin, up to 200 parts by weight of a diffuser having a refractive index different from that of the epoxy resin and having an average particle diameter of from 0.
    Type: Application
    Filed: November 6, 2003
    Publication date: June 24, 2004
    Applicant: NITTO DENKO CORPORATION
    Inventors: Yoshimasa Sakata, Toshiyuki Umehara, Kiichi Shimodaira, Kazutaka Hara, Yoshihiro Kitamura, Katsuhiro Nakano