Patents by Inventor Yuji Egi

Yuji Egi 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: 7728928
    Abstract: It is an object to provide a display device with the high contrast ratio by an easy method. In addition, it is an object to provide such a high performance display device at low cost. In a display device including a display element between a pair of light transmitting substrates, a layer including stacked polarizers is each provided on an outer side of the substrates. At that time, the stacked polarizers on a viewing side are arranged to deviate from a parallel nicol state. In addition, a retardation film may be provided between the stacked polarizers and the substrate.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: June 1, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tetsuji Ishitani, Yuji Egi, Takeshi Nishi
  • Publication number: 20100096637
    Abstract: Off current of a thin film transistor is reduced, and on current of the thin film transistor is increased, and variation in electric characteristics is reduced. As a structure of semiconductor layers which form a channel formation region of a thin film transistor, a first semiconductor layer including a plurality of crystalline regions is provided on a gate insulating layer side; a second semiconductor layer having an amorphous structure is provided on a source region and drain region side; an insulating layer with a thickness small enough to allow carrier travel is provided between the first semiconductor layer and the second semiconductor layer. The first semiconductor layer is in contact with the gate insulating layer. The second semiconductor layer is provided on an opposite side to a face of the first semiconductor layer which is in contact with the gate insulating layer.
    Type: Application
    Filed: April 15, 2009
    Publication date: April 22, 2010
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei Yamazaki, Yuji Egi, Shinya Sasagawa, Motomu Kurata
  • Publication number: 20100096631
    Abstract: A thin film transistor includes, over a substrate having an insulating surface, a gate insulating layer covering a gate electrode; a semiconductor layer which includes a plurality of crystalline regions in an amorphous structure and which forms a channel formation region, in contact with the gate insulating layer; a semiconductor layer including an impurity element imparting one conductivity type, which forms source and drain regions; and a buffer layer including an amorphous semiconductor between the semiconductor layer and the semiconductor layer including an impurity element imparting one conductivity type. The crystalline regions have an inverted conical or inverted pyramidal crystal particle which grows approximately radially in a direction in which the semiconductor layer is deposited, from a position away from an interface between the gate insulating layer and the semiconductor layer.
    Type: Application
    Filed: April 14, 2009
    Publication date: April 22, 2010
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hidekazu MIYAIRI, Koji DAIRIKI, Yuji EGI, Yasuhiro JINBO, Toshiyuki ISA
  • Patent number: 7687988
    Abstract: The invention provides a display device of which a contrast ratio is enhanced. By providing stacked polarizing plates so as to be in a cross nicol state, a contrast ratio of a display device can be enhanced. The stacked polarizing plates are stacked outside a light-transmissive insulating substrate in a parallel nicol state. When the number of polarizing plates is four or five in total, a contrast ratio becomes the highest.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: March 30, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tetsuji Ishitani, Yuji Egi, Takeshi Nishi, Koji Moriya
  • Patent number: 7659669
    Abstract: To provide a PDP and an FED with high visibility, having an anti-reflection function capable of reducing reflection of incident light from external. An anti-reflection layer including a plurality of pyramid-shaped projections, apexes of which are provided at equal intervals and in which each side of a base which forms a pyramid shape of one of the plurality of pyramid-shaped projections is in contact with a side of a base which forms a pyramid shape of an adjacent pyramid-shaped projection, is included. In other words, one pyramid-shaped projection is surrounded by other pyramid-shaped projections, and the base of the pyramid-shaped projection shares a side of a base with the base of the adjacent pyramid-shaped projection.
    Type: Grant
    Filed: December 5, 2007
    Date of Patent: February 9, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Jiro Nishida, Yuji Egi, Takeshi Nishi, Shunpei Yamazaki
  • Publication number: 20090261328
    Abstract: Disclosed is a thin film transistor which includes, over a substrate having an insulating surface, a gate insulating layer covering a gate electrode; a semiconductor layer which functions as a channel formation region; and a semiconductor layer including an impurity element imparting one conductivity type. The semiconductor layer exists in a state that a plurality of crystalline particles is dispersed in an amorphous silicon and that the crystalline particles have an inverted conical or inverted pyramidal shape. The crystalline particles grow approximately radially in a direction in which the semiconductor layer is deposited. Vertexes of the inverted conical or inverted pyramidal crystal particles are located apart from an interface between the gate insulating layer and the semiconductor layer.
    Type: Application
    Filed: April 14, 2009
    Publication date: October 22, 2009
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hidekazu MIYAIRI, Koji DAIRIKI, Yuji EGI, Yasuhiro JINBO, Toshiyuki ISA
  • Publication number: 20080165315
    Abstract: An object of the present invention is to provide an antireflective film having an anti-reflection function with which reflection of incident light from external can be further reduced and a high-visibility display device having such an antireflective film. The tops of the plurality of pyramidal projections are evenly spaced and each side of the base of a pyramidal projection is in contact with one side of the base of an adjacent pyramidal projection. That is, one pyramidal projection is surrounded by other pyramidal projections, and the base of the pyramidal projection and the base of the adjacent pyramidal projection have a side in common.
    Type: Application
    Filed: December 5, 2007
    Publication date: July 10, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Jiro NISHIDA, Yuji EGI, Takeshi NISHI, Shunpei YAMAZAKI
  • Publication number: 20080158682
    Abstract: It is an object to provide a high-visibility antireflection film having an antireflection function which can further reduce reflection and a display device that has the antireflection film. A plurality of projections in a pyramidal shape (hereinafter, referred to as pyramidal projection) that are adjacent to each other are provided, and the refractive index of the projection is made to change by the physical pyramidal shape to the outer side (air side) from a surface of a display screen, so that reflection of light is prevented. In addition, the plurality of pyramidal projections are each covered with a film formed of a material having a higher refractive index than the pyramidal projections.
    Type: Application
    Filed: December 5, 2007
    Publication date: July 3, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Yuji EGI, Jiro NISHIDA, Takeshi NISHI
  • Publication number: 20080144180
    Abstract: To provide a PDP and an FED with high visibility, having an anti-reflection function capable of reducing reflection of incident light from external. An anti-reflection layer including a plurality of pyramid-shaped projections, apexes of which are provided at equal intervals and in which each side of a base which forms a pyramid shape of one of the plurality of pyramid-shaped projections is in contact with a side of a base which forms a pyramid shape of an adjacent pyramid-shaped projection, is included. In other words, one pyramid-shaped projection is surrounded by other pyramid-shaped projections, and the base of the pyramid-shaped projection shares a side of a base with the base of the adjacent pyramid-shaped projection.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 19, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Jiro NISHIDA, Yuji EGI, Takeshi NISHI, Shunpei YAMAZAKI
  • Publication number: 20080129188
    Abstract: To provide a plasma display panel and a field emission display having an anti-reflection function which can further reduce reflection of incident light from an external source. By providing an anti-reflection layer which geometrically includes a plurality of adjacent hexagonal pyramid-shaped projections, reflection of light is prevented. The reflective index changes from a surface side of display screen to an out side (an atmosphere side) due to a physical shape of a hexagonal pyramid. The plurality of hexagonal pyramid-shaped projections can be provided densely without any space remaining, and six surfaces of side of the hexagonal pyramid-shaped projection are each provided at different angles to a base surface. Therefore, light ray can be effectively scattered in many directions.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 5, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Yuji EGI, Jiro NISHIDA, Takeshi NISHI, Shunpei YAMAZAKI
  • Publication number: 20080129933
    Abstract: An anti-reflection film that can provide high visibility and has an anti-reflection function by which reflection of incident light from external can be further reduced, and a display device having such an anti-reflection film. A plurality of contiguous pyramidal projections is arranged in a geometric pattern, so that reflection of incident light is prevented. In addition, a protective layer formed of a material having a lower refractive index than the pyramidal projections is provided so as to fill a space between the plurality of pyramidal projections. The plurality of pyramidal projections has a hexagonal shape and can be densely arranged with no space therebetween. Further, since six sides of each pyramidal projection are provided at a different angle from the base, light can be effectively scattered in many directions.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 5, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Jiro NISHIDA, Yuji EGI, Takeshi NISHI, Shunpei YAMAZAKI
  • Publication number: 20080129184
    Abstract: It is an object to provide a plasma display and a field emission display that each have high visibility and an anti-reflection function that can further reduce reflection of incident light from external. Reflection of light can be prevented by having an anti-reflection layer that geometrically includes a plurality of adjacent pyramidal projections. In addition, a plurality of hexagonal pyramidal projections, each of which is provided with a protective layer formed of a material having a lower refractive index than a refractive index of the pyramidal projection so as to fill a space among the plurality of pyramidal projections, can be provided to be packed together without any spaces. Further, six sides of a pyramidal projection face different directions with respect to a base. Therefore, light can be diffused in many directions efficiently.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 5, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Jiro NISHIDA, Yuji EGI, Takeshi NISHI, Shunpei YAMAZAKI
  • Publication number: 20080129183
    Abstract: It is an object of the present invention to provide a PDP and an FED with excellent visibility and a high level of reliability that each have an antireflective function by which reflection of external light can be reduced. A plurality of adjacent pyramidal-shaped projections and an antireflective layer equipped with a covering film that covers the projections are provided. The reflection of light is prevented by the index of refraction of incident light from external being changed by a pyramid, which is a physical shape, projecting out toward an external side (atmosphere side) of a substrate that is to be used as a display screen as well as by the covering film used to cover the projections being formed of a material that has a higher index of refraction than the index of refraction of the pyramidal projection.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 5, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Yuji EGI, Jiro NISHIDA, Takeshi NISHI
  • Publication number: 20080130122
    Abstract: An object is to provide an anti-reflection film which has an anti-reflection function capable of further reducing reflection of incident light from external, and has excellent visibility, and a display device having the anti-reflection film. A plurality of adjacent hexagonal pyramidal projections is geometrically provided, so that reflection of light is prevented. A refractive index is changed from a display screen surface side to the outside (the air side) because of a physical form that is a hexagonal pyramid. The plurality of hexagonal pyramidal projections can be provided without gaps therebetween and each of six side surfaces thereof is provided at an different angle from a base; thus, light can be sufficiently scattered in many directions.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 5, 2008
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Yuji EGI, Jiro NISHIDA, Takeshi NISHI, Shunpei YAMAZAKI
  • Publication number: 20080042926
    Abstract: The display device includes an anti-reflection film having a plurality of projections over a display screen surface and a protective layer filling a space between the projections. The number of times of incidence of external light entering the display device on the anti-reflection film is increased; therefore, the amount of external light transmitted through the anti-reflection film is increased. Thus, the amount of external light reflected to a viewer side is reduced, and the cause of a reduction in visibility such as reflection can be eliminated. Further, since the plurality of projections is covered with a protective layer, entry of dust can be prevented, and physical strength of the anti-reflection film can be increased.
    Type: Application
    Filed: May 29, 2007
    Publication date: February 21, 2008
    Inventors: Yuji Egi, Takeshi Nishi, Kiyofumi Ogino, Shinya Sasagawa, Motomu Kurata, Hideomi Suzawa
  • Publication number: 20070284991
    Abstract: A display device includes an anti-reflection film having a plurality of projections over a display screen surface. An angle made by a base and a slope of each of the plurality of projections is equal to or greater than 84° and less than 90°.
    Type: Application
    Filed: May 30, 2007
    Publication date: December 13, 2007
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Yuji Egi, Takeshi Nishi, Kiyofumi Ogino, Shinya Sasagawa, Motomu Kurata, Hideomi Suzawa
  • Publication number: 20070200978
    Abstract: An object is to provide a display device with high contrast ratio. Another object is to manufacture such a high-performance display device at low cost. In a display device having a display element interposed between a pair of light-transmitting substrates, a stack of polarizer-including layers in a parallel nicol state is provided outside each of the light-transmitting substrates. Here, transmission axes of polarizers that are stacked in the stack on one side of the display element and transmission axes of polarizers that are stacked in the stack on another side of the display element are arranged to be displaced from a cross nicol state. Also, a retardation film may be provided between the polarizers that are stacked and the substrate.
    Type: Application
    Filed: February 21, 2007
    Publication date: August 30, 2007
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Tetsuji ISHITANI, Takeshi NISHI, Yuji EGI
  • Publication number: 20070200977
    Abstract: An object of the invention is to provide a display device having a high contrast ratio. Another object of the invention is to manufacture such a high-performance display device at low cost. In a display device having a display element between a pair of light-transmissive substrates, polarizer-including layers, which have different wavelength distributions of extinction coefficients, are stacked so that absorption axes are in a parallel nicol state, over each light-transmissive substrate. Absorption axes of one of a pair of stacks of polarizers and the other together which interpose the display element are deviated from a cross nicol state. A retardation plate may be provided between the stack of polarizing plates and the substrate.
    Type: Application
    Filed: February 21, 2007
    Publication date: August 30, 2007
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Yuji Egi, Tetsuji Ishitani, Takeshi Nishi
  • Publication number: 20070182885
    Abstract: The present invention provides a display device with higher contrast ratio. The display device includes a first substrate, a second substrate, a layer including a display element which is interposed between the first substrate and the second substrate, and stacked polarizers on an outer side of the first substrate or the second substrate. The stacked polarizers are arranged to be in parallel Nicols. The stacked polarizers have the same wavelength distribution in the extinction coefficients. Further, a retardation plate may be provided between the stacked polarizers and the first substrate or the second substrate. The stacked polarizers are provided for both of the first substrate and the second substrate, and the stacked polarizers on the outer side of the first substrate and the stacked polarizers on the outer side of the second substrate are arranged to be in crossed Nicols or parallel Nicols.
    Type: Application
    Filed: January 31, 2007
    Publication date: August 9, 2007
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Yuji EGI, Takeshi NISHI, Tetsuji ISHITANI
  • Publication number: 20070177084
    Abstract: It is an object to provide a display device with the high contrast ratio by an easy method. In addition, it is an object to provide such a high performance display device at low cost. In a display device including a display element between a pair of light transmitting substrates, a layer including stacked polarizers is each provided on an outer side of the substrates. At that time, the stacked polarizers on a viewing side are arranged to deviate from a parallel nicol state. In addition, a retardation film may be provided between the stacked polarizers and the substrate.
    Type: Application
    Filed: January 23, 2007
    Publication date: August 2, 2007
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Tetsuji ISHITANI, Yuji EGI, Takeshi NISHI