Patents by Inventor Yasushi Tomioka

Yasushi Tomioka 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: 8873006
    Abstract: The present invention prevents the shaving of an alignment film caused by a columnar spacer in a liquid crystal display device of an IPS method using photo-alignment. A plinth higher than a pixel electrode is formed at a part where a columnar spacer formed over a counter substrate touches a TFT substrate. When an alignment film of a double-layered structure is applied over the pixel electrode and the plinth, the thickness of the alignment film over the plinth reduces by a leveling effect. When photo-alignment is applied in the state, a photodegraded upper alignment film over the plinth disappears and a lower alignment film having a high mechanical strength remains. As a result, it is possible to prevent the shaving of the alignment film.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: October 28, 2014
    Assignee: Japan Display Inc.
    Inventors: Noboru Kunimatsu, Masaki Matsumori, Hidehiro Sonoda, Yasushi Tomioka, Toshiki Kaneko
  • Publication number: 20140307209
    Abstract: A high-definition and high-contrast liquid crystal display device having a high aperture ratio without light leakage around a columnar spacer is provided. The liquid crystal display device of a horizontal electric field type includes a TFT substrate with a pixel electrode and a common electrode, a color filter substrate with a color filter, a columnar spacer interposed between the substrates, and a liquid crystal layer arranged between the substrates. A liquid crystal alignment film formed between the substrates is a photo-alignment film. The columnar spacer, formed on the color filter substrate or the TFT substrate, has a wall-like shape and an inclined surface extending in a direction parallel to or perpendicular to a direction in which the liquid crystal is initially aligned.
    Type: Application
    Filed: April 10, 2014
    Publication date: October 16, 2014
    Applicant: Japan Display Inc.
    Inventors: Yasushi TOMIOKA, Osamu ITOU, Toshimasa ISHIGAKI, Hidehiro SONODA, Yosuke HYODO
  • Publication number: 20140307212
    Abstract: A pixel electrode formed into a slit structure with striped electrodes opposed to each other for a zero rubbing angle can provide fast response since rotational directions of the liquid crystals become opposite at both sides of the slit in the striped electrodes. The electrode structure, however, poses a problem of low transmittance. Provided is a liquid crystal display device of IPS-Pro scheme including a pixel electrode with one pair of striped electrodes, an electrode section of one of striped electrodes being partially interposed between electrode sections of other striped electrode, and liquid crystals being oriented in a lengthwise direction of the striped electrodes.
    Type: Application
    Filed: April 10, 2014
    Publication date: October 16, 2014
    Applicant: Japan Display Inc.
    Inventors: Shinichiro OKA, Mika OIWA, Yasushi TOMIOKA, Toshiharu MATSUSHIMA
  • Patent number: 8854582
    Abstract: A method for fabricating a liquid crystal display device having a TFT substrate in which an alignment film is formed over a pixel including a pixel electrode and a TFT, an opposing substrate which faces the TFT substrate, and liquid crystals sandwiched between the TFT substrate and the opposing substrate, the alignment film on the TFT substrate including a first and a second alignment film. The method includes depositing a mixture liquid of polyamide acid ester, 80 percent or more of which is polyamide acid ester including cyclobutane, and polyamide acid not including cyclobutane onto the TFT substrate and the opposing substrate, and after drying and firing the TFT substrate and the opposing substrate to harden the alignment film, irradiating the alignment film with ultraviolet light for photo-alignment of the alignment film and, thereafter, heating the TFT substrate and the opposing substrate, thereby forming the alignment film.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: October 7, 2014
    Assignees: Japan Display Inc., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Noboru Kunimatsu, Chikae Matsui, Hidehiro Sonoda, Yuko Matsumoto, Shoichi Uchino, Masaki Matsumori, Yasushi Tomioka
  • Patent number: 8848157
    Abstract: A liquid crystal display includes: a pair of substrates including at least one transparent substrate; a liquid crystal layer disposed between the pair of substrates; and an electrode group formed on at least one of the pair of substrates so as to apply an electric field to the liquid crystal layer. The liquid crystal layer contains at least one kind of liquid crystalline compound and at least one kind of chiral dopant. The concentration c of the chiral dopant is lower than a saturation solubility s thereof. The concentration c of the chiral dopant and a helical twisting power [HTP] of the chiral dopant satisfy a relation of [HTP]·c?5.5 (?m?1).
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: September 30, 2014
    Assignees: Japan Display Inc., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Mika Oiwa, Shintaro Takeda, Kotaro Araya, Yasushi Tomioka, Yoshiro Mikami
  • Publication number: 20140248445
    Abstract: A liquid crystal display is provided which is capable of reducing the occurrence of defective display due to variations in the initial alignment direction of a liquid crystal alignment control film in a liquid crystal display of an IPS scheme, realizing the stable liquid crystal alignment, providing excellent mass productivity, and having high image quality with a higher contrast ratio. The liquid crystal display has a liquid crystal layer disposed between a pair of substrates, at least one of the substrates being transparent, and an alignment control film formed between the liquid crystal layer and the substrate. At least one of the alignment control films 109 comprises photoreactive polyimide and/or polyamic acid provided with an alignment control ability by irradiation of substantially linearly polarized light.
    Type: Application
    Filed: May 9, 2014
    Publication date: September 4, 2014
    Applicants: JAPAN DISPLAY INC., PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD.
    Inventors: Yasushi TOMIOKA, Hidetoshi ABE, Katsumi KONDO
  • Patent number: 8797496
    Abstract: In a liquid crystal display device, a TFT substrate retains a contact hole that is formed in a passivation film, and is for connecting the TFT and the pixel electrode. And an opposite substrate retains a columnar spacer for ensuring a cell gap, and a columnar projection for misalignment prevention formed at a position corresponding to a position of the contact hole. Accordingly, misalignment between the TFT substrate and the opposite substrate is suppressed, occurrence of uneven brightness due to misalignment between pixel regions and a bright spot caused by shaving of an orientation film is prevented, and a favorable image is obtained.
    Type: Grant
    Filed: July 17, 2012
    Date of Patent: August 5, 2014
    Assignee: Japan Display Inc.
    Inventors: Yasushi Tomioka, Noboru Kunimatsu, Hidehiro Sonoda, Yasuo Imanishi, Koichi Igeta
  • Patent number: 8758871
    Abstract: A liquid crystal display is provided which is capable of reducing the occurrence of defective display due to variations in the initial alignment direction of a liquid crystal alignment control film in a liquid crystal display of an IPS scheme, realizing the stable liquid crystal alignment, providing excellent mass productivity, and having high image quality with a higher contrast ratio. The liquid crystal display has a liquid crystal layer disposed between a pair of substrates, at least one of the substrates being transparent, and an alignment control film formed between the liquid crystal layer and the substrate. At least one of the alignment control films 109 comprises photoreactive polyimide and/or polyamic acid provided with an alignment control ability by irradiation of substantially linearly polarized light.
    Type: Grant
    Filed: August 17, 2011
    Date of Patent: June 24, 2014
    Assignees: Japan Display Inc., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Yasushi Tomioka, Hidetoshi Abe, Katsumi Kondo
  • Publication number: 20140144582
    Abstract: A method for fabricating a liquid crystal display device having a TFT substrate in which an alignment film is formed over a pixel including a pixel electrode and a TFT, an opposing substrate which faces the TFT substrate, and liquid crystals sandwiched between the TFT substrate and the opposing substrate, the alignment film on the TFT substrate including a first and a second alignment film. The method includes depositing a mixture liquid of polyamide acid ester, 80 percent or more of which is polyamide acid ester including cyclobutane, and polyamide acid not including cyclobutane onto the TFT substrate and the opposing substrate, and after drying and firing the TFT substrate and the opposing substrate to harden the alignment film, irradiating the alignment film with ultraviolet light for photo-alignment of the alignment film and, thereafter, heating the TFT substrate and the opposing substrate, thereby forming the alignment film.
    Type: Application
    Filed: January 29, 2014
    Publication date: May 29, 2014
    Applicants: Panasonic Liquid Crystal Display Co., Ltd., Japan Display Inc.
    Inventors: Noboru Kunimatsu, Chikae Matsui, Hidehiro Sonoda, Yuko Matsumoto, Shoichi Uchino, Masaki Matsumori, Yasushi Tomioka
  • Patent number: 8734917
    Abstract: A liquid crystal display device includes: a pair of substrates, at least one of which is transparent; a liquid crystal layer placed between the pair of substrates; an electrode group, formed on at least one of the pair of substrates, for applying an electric field to the liquid crystal layer; and an alignment control film placed on at least one of the pair of substrates, in which the alignment control film is formed of polyimide and a precursor of the polyimide, each of the polyimide and the precursor of the polyimide contains, as a material, a specific cyclobutanetetracarboxylic acid dianhydride derivative and aromatic diamine, and the alignment control film is provided with alignment capability by photo-alignment treatment.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: May 27, 2014
    Assignees: Japan Display Inc., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Masaki Matsumori, Yasushi Tomioka
  • Publication number: 20140125905
    Abstract: A liquid crystal display device includes a liquid crystal composition, a thin film transistor substrate as an insulation substrate on which a thin film transistor for controlling the orientation of the liquid crystal composition is provided, and a color filter substrate which seals the liquid crystal composition between itself and the thin film transistor substrate and controls a wavelength region of the transmitted light. The thin film transistor substrate includes a projection part extending from the thin film transistor substrate to the color filter substrate side, and a wall-like electrode on a wall surface of the projection part, which is one electrode for controlling the orientation of the liquid crystal composition. An insulation film and an orientation film are sequentially laminated on the wall-like electrode continuously from a surface parallel to a substrate surface.
    Type: Application
    Filed: October 29, 2013
    Publication date: May 8, 2014
    Applicant: Japan Display Inc.
    Inventors: Chikae MATSUI, Yasushi TOMIOKA, Takato HIRATSUKA
  • Publication number: 20140104553
    Abstract: A liquid crystal display device includes first and second substrates, at least one of which is transparent, a liquid crystal layer which is disposed between the first and second substrates, a pixel electrode and a common electrode which are formed on one of the first and second substrates and which apply an electric field to the liquid crystal layer, a plurality of active elements which is connected to the pixel electrode and the common electrode, an alignment film which is disposed on at least one of the first and second substrates and has one surface contacting the liquid crystal layer, and an underlying layer which is disposed on at least one of the first and second substrates and contacts the other surface of the alignment film. The pixel electrode is laminated on the common electrode having a plane shape through an isolation film.
    Type: Application
    Filed: December 13, 2013
    Publication date: April 17, 2014
    Applicants: Panasonic Liquid Crystal Display Co., Ltd., Japan Display Inc.
    Inventors: Yasuo Imanishi, Masaki Matsumori, Yasushi Tomioka
  • Publication number: 20140043551
    Abstract: In the step of curing a resin for bonding a TFT substrate and a counter substrate each having an alignment film that has been optically aligned by using UV-light, damage to the alignment film due to the UV-light can be prevented without using a light shielding mask. A UV-light absorption layer is formed between each black matrix on the counter substrate. The TFT and counter substrates are sealed at their periphery by a resin that is cured by UV-light radiated from the counter substrate side. Since the absorption layer has a high absorbability to UV-light at a wavelength of 300 nm or less that degrades the alignment film, damage to the alignment film due to the UV-light for curing the resin can be prevented. Thus, provision of a light shielding mask for shielding the UV-light for the display region can be saved.
    Type: Application
    Filed: October 22, 2013
    Publication date: February 13, 2014
    Applicant: HITACHI DISPLAYS, LTD.
    Inventors: Noboru KUNIMATSU, Yuko MATSUMOTO, Yasushi TOMIOKA, Masateru MORIMOTO, Atsuhiro KATAYAMA
  • Publication number: 20140046004
    Abstract: An IPS type liquid crystal display device superior in mass productivity and improved in image quality with a higher contrast ratio by decreasing the occurrence of defective display due to the disorder of the initial liquid crystal alignment by the liquid orientation control film and realizing stable alignment of liquid crystals comprises: a pair of substrates, at least one which is transparent; a liquid crystal layer disposed between the pair of substrates; a group of electrodes formed on at least one of the pair of substrates to apply an electric field to the liquid crystal layer; plural active elements connected to the group of electrodes; and an orientation control film disposed on at least one of the pair of substrates, wherein said orientation control film is made of a photosensitive polyimide and a polyamide acid ester and is given orientation control ability by being irradiated with substantially linearly polarized light.
    Type: Application
    Filed: October 23, 2013
    Publication date: February 13, 2014
    Applicant: JAPAN DISPLAY, INC.
    Inventors: Masaki Matsumori, Yasushi Tomioka, Noboru Kunimatsu
  • Patent number: 8648988
    Abstract: This invention enables forming a photo-alignment film having a large LC anchoring strength in an IPS type liquid crystal display device. An alignment film is adapted to have a two-layer structure including a photo-alignment film and an alignment film with enhanced film strength. The photo-alignment film is formed of a precursor of polyamide acid ester, 80 percent or more of which is polyamide acid ester including cyclobutane. The alignment film with enhanced film strength is formed of a precursor of polyamide acid. After irradiating the substrate with ultraviolet light for photo-alignment, the substrate is heated. Thus, it is possible to achieve a high LC anchoring strength of the alignment film as the whole for photo-alignment, without degrading the mechanical strength of the alignment film with enhanced film strength.
    Type: Grant
    Filed: February 16, 2011
    Date of Patent: February 11, 2014
    Assignees: Hitachi Displays, Ltd., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Noboru Kunimatsu, Chikae Matsui, Hidehiro Sonoda, Yuko Matsumoto, Shoichi Uchino, Masaki Matsumori, Yasushi Tomioka
  • Publication number: 20140009711
    Abstract: A liquid crystal display device in a lateral electric field mode includes: a metal wiring formed on a transparent substrate; an inorganic insulating film and an organic insulating film formed on the metal wiring; and a first transparent electrode and a second transparent electrode formed on the inorganic insulating film and the organic insulating film so that the first and the second transparent electrodes are opposite to each other through an interlayer insulating film. The film thickness of the organic insulating film on the metal wiring is made thicker than the film thickness of the organic insulating film inside a pixel display region including the contact hole, and a projecting portion of the organic insulating film is formed on the metal wiring. A pixel electrode formed of the first electrode or the second electrode is formed on an image display region including a slope portion of the projecting portion.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 9, 2014
    Inventors: Yasushi TOMIOKA, Chikae MATSUI, Noboru KUNIMATSU, Hidehiro SONODA
  • Patent number: 8610855
    Abstract: Provided is a liquid crystal display device having a structure in which one surface of the alignment film contacts a liquid crystal layer, the other surface of the alignment film contacts an underlying layer, the refractive index of the alignment film monotonically increases in a film thickness direction of the alignment film from a boundary surface between the liquid crystal layer and the alignment film to a boundary surface between the underlying layer and the alignment film, and the minimum refractive index nLC of the liquid crystal layer, the refractive index nF2 of the alignment film at the boundary surface between the liquid crystal layer and the alignment film, the refractive index nF1 of the alignment film at the boundary surface between the alignment film and the underlying layer, and the refractive index nS2 of the underlying layer have a relationship of an equation (I) in which nLC?nF2<nF1?nS2.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: December 17, 2013
    Assignees: Japan Display Inc., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Yasuo Imanishi, Masaki Matsumori, Yasushi Tomioka
  • Patent number: 8593596
    Abstract: In the step of curing a resin for bonding a TFT substrate and a counter substrate each having an alignment film that has been optically aligned by using UV-light, damage to the alignment film due to the UV-light can be prevented without using a light shielding mask. A UV-light absorption layer is formed between each black matrix on the counter substrate. The TFT and the counter substrates are sealed at their periphery by a resin that is cured by UV-light radiated from the counter substrate side. Since the absorption layer has a high absorbability to UV-light at a wavelength of 300 nm or less that degrades the alignment film, damage to the alignment film due to the UV-light for curing the resin can be prevented. Thus, provision of a light shielding mask for shielding the UV-light for the display region can be saved.
    Type: Grant
    Filed: February 16, 2012
    Date of Patent: November 26, 2013
    Assignee: Hitachi Displays, Ltd.
    Inventors: Noboru Kunimatsu, Yuko Matsumoto, Yasushi Tomioka, Masateru Morimoto, Atsuhiro Katayama
  • Patent number: 8592009
    Abstract: A liquid crystal display device superior in mass productivity and improved image quality with a higher contrast ratio by decreasing the occurrence of defective display due to the disorder of the initial liquid crystal alignment and realizing stable alignment of liquid crystals, comprising: a pair of substrates 101 and 102, at least one of which is transparent; a liquid crystal layer 110? disposed between the pair of substrates; a group of electrodes formed on at least one of the pair of substrates to apply an electric field to the liquid crystal layer; plural active elements 115 connected to the group of electrodes; and an orientation control film 109 disposed on at least one of the pair of substrates, wherein said orientation control film made of a photosensitive polyimide, a polyamide acid ester and a polyamide acid is given orientation control ability by being irradiated with substantially linearly polarized light.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: November 26, 2013
    Assignees: Hitachi Display, Ltd., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Masaki Matsumori, Yasushi Tomioka, Noboru Kunimatsu
  • Patent number: 8580357
    Abstract: A liquid crystal display device includes: a pair of substrates, at least one of which is transparent; a liquid crystal layer placed between the pair of substrates; an electrode group, formed on at least one of the pair of substrates, for applying an electric field to the liquid crystal layer; and an alignment control film placed on at least one of the pair of substrates, in which the alignment control film is formed of polyimide and a precursor of the polyimide, each of the polyimide and the precursor of the polyimide contains, as a material, a specific cyclobutanetetracarboxylic acid dianhydride derivative and aromatic diamine, and the alignment control film is provided with alignment capability by photo-alignment treatment.
    Type: Grant
    Filed: February 16, 2011
    Date of Patent: November 12, 2013
    Assignees: Hitachi Displays, Ltd., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Masaki Matsumori, Yasushi Tomioka