Patents by Inventor Tomohiro Sasagawa

Tomohiro Sasagawa 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: 6753548
    Abstract: The laser heat treatment of an amorphous or polycrystalline silicon film material is conducted by forming a laser beam generated from a pulse laser source having a wavelength of 350 nm to 800 nm into a linear beam having a width and a length, and directing the linear beam onto a film material formed on a substrate.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: June 22, 2004
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Seiko Epson Corporation
    Inventors: Tetsuya Ogawa, Hidetada Tokioka, Yukio Sato, Mitsuo Inoue, Tomohiro Sasagawa, Mitsutoshi Miyasaka
  • Patent number: 6738116
    Abstract: A reflective liquid crystal display device having a structure providing high contrast even if there is undesired light. The structure includes a light-guiding plate for receiving, from a light-incident surface, light coming from a light source, and for allowing the light to exit from a bottom surface; a reflective liquid crystal display panel opposed to the bottom surface of the light-guiding plate; and a prism disposed on the side of a top surface of an upper substrate of the liquid crystal display panel. The prism has a surface that is substantially perpendicular to the top surface of the upper substrate, and a tilted surface which is tilted towards a side opposite to the light source from a crest line of the substantially perpendicular surface at a tilt angle with respect to an imaginary surface which passes through the crest line and which is parallel to the top surface of the upper substrate.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: May 18, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tomohiro Sasagawa, Akimasa Yuuki, Toshio Tobita
  • Patent number: 6724546
    Abstract: Lengths of both sides of each end plane of a light-intensity distribution uniformizing element receiving a light flux and having an F-number of 1 are set to ½ of those of a reflecting surface of a reflecting optical-spatial modulator element, position information of uniformed light fluxes output from the light-intensity distribution uniformizing element is Fourier-transformed into diverging angle information indicated by incident light fluxes output from a first group of lenses, a relay deformed diaphragm intercepts an interference component of each incident light flux, which is expected to interfere with an outgoing light flux, to produce asymmetric light fluxes, the asymmetric light fluxes are incident on the reflecting optical-spatial modulator element, a projection lens deformed diaphragm removes stray light from outgoing light fluxes output from the reflecting optical-spatial modulator element, and an image is displayed according to the outgoing light fluxes.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: April 20, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Junichi Nishimae, Akira Sekiguchi, Tomohiro Sasagawa, Yoshiyuki Goto, Kohei Teramoto, Hiroyuki Kawano, Tatsuki Okamoto, Yukio Satou, Atsuhiro Sono
  • Publication number: 20040070735
    Abstract: A lamp (1) has a deformed lamp reflector (1b) and a lamp front glass (1c). The deformed lamp reflector (1b) is made by deforming an ellipsoidal of revolution of a conventional lamp reflector (10b) to an aspherical reflection surface rotationally symmetric with respect to an optical axis Z. The lamp front glass (1c) is obtained by deforming at least one of incident plane and outgoing plane of a conventional lamp front glass (101c) to an aspherical lens surface rotationally symmetric with respect to the optical axis Z. A light flux emitted from the center point (Pf) of the illuminant (1a) is reflected by the deformed lamp reflector (1b), and outputted with a uniform density through the entire of the outgoing plane of the lamp front lens (1c) so that the light flux is condensed at the focus point.
    Type: Application
    Filed: October 3, 2003
    Publication date: April 15, 2004
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Sekiguchi, Tomohiro Sasagawa, Junichi Nishimae, Yoshiyuki Goto, Kohei Teramoto
  • Publication number: 20040027513
    Abstract: A double-side display type liquid crystal display device including a liquid crystal, first and second electrodes for driving the liquid crystal, first and second polarizing means disposed on both sides of the liquid crystal, a front light disposed at the opposite side of the liquid crystal of the first polarizing means, and semitransmission reflecting means disposed at the second polarizing means side of the liquid crystal for passing a part of light from the front light side passing through the liquid crystal. The first polarizing means is optically disposed so as to absorb or transmit light passing through the liquid crystal, and the second polarizing means is optically disposed so as to absorb or transmit light passing through the liquid crystal and then passing through the semitransmission reflecting means.
    Type: Application
    Filed: May 20, 2003
    Publication date: February 12, 2004
    Inventors: Akimasa Yuuki, Tomohiro Sasagawa, Naoto Sugawara, Takashi Yamamoto
  • Publication number: 20040021827
    Abstract: A lamp has a deformed lamp reflector (1b) and a lamp front glass (1c). The deformed lamp reflector (1b) is formed by deforming a paraboloid of revolution of a conventional lamp reflector (101b) to an aspherical reflection surface which is rotationally symmetric symmetrical with respect to an optical axis Z. The lamp front glass (1c) is obtained by deforming the incident plane of a conventional lamp front glass (101c) to an aspherical lens surface rotationally symmetric with respect to the optical axis Z. A light flux irradiated radiated from the center point Pf of the light source of an illuminant (1a) is reflected by the deformed lamp reflector (1b), and is output through the lens (1c) as a parallel light flux having a circular cross section equal in area to the outgoing plane of the lens (1c).
    Type: Application
    Filed: July 30, 2003
    Publication date: February 5, 2004
    Inventors: Akira Sekiguchi, Tomohiro Sasagawa, Junichi Nishimae, Yoshiyuki Goto, Kohei Teramoto
  • Publication number: 20030202259
    Abstract: Lengths of both sides of each end plane of a light-intensity distribution uniformizing element receiving a light flux of an F-number of 1 are set to ½ of those of a reflecting surface of a reflection type optical-spatial modulator element, position information of uniformed light fluxes output from the light-intensity distribution uniformizing element is Fourier-transformed into diverging angle information indicated by incident light fluxes output from a first group of lenses, a relay deformed diaphragm intercepts an interference component of each incident light flux, which is expected to interfere with an outgoing light flux, to produce asymmetric light fluxes, the asymmetric light fluxes are incident on the reflection type optical-spatial modulator element, a projection lens deformed diaphragm removes stray light from outgoing light fluxes output from the reflection type optical-spatial modulator element, and an image is displayed according to the outgoing light fluxes.
    Type: Application
    Filed: October 10, 2002
    Publication date: October 30, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Junichi Nishimae, Akira Sekiguchi, Tomohiro Sasagawa, Yoshiyuki Goto, Kohei Teramoto, Hiroyuki Kawano, Tatsuki Okamoto, Yukio Satou, Atsuhiro Sono
  • Publication number: 20030201466
    Abstract: The laser heat treatment of an amorphous or polycrystalline silicon film material is conducted by forming a laser beam generated from a pulse laser source having a wavelength of 350 nm to 800 nm into a linear beam having a width and a length, and directing the linear beam onto a film material formed on a substrate.
    Type: Application
    Filed: April 23, 2003
    Publication date: October 30, 2003
    Applicants: MITSUBISHI DENKI KABUSHIKI KAISHA, SEIKO EPSON CORPORATION
    Inventors: Tetsuya Ogawa, Hidetada Tokioka, Yukio Sato, Mitsuo Inoue, Tomohiro Sasagawa, Mitsutoshi Miyasaka
  • Patent number: 6636283
    Abstract: A compact and light weight front light, a reflective liquid crystal display device, and a personal digital assistant providing an image display of uniform brightness with high efficiency are provided. The front light includes a main optical guide plate and a second optical guide plate. The second optical guide plate is arranged at an end of the main optical guide plate along the widthwise direction, and, on an end surface opposite an end surface facing the main optical guide plate, grooves forming prisms are aligned along the longitudinal direction, extending in the depth direction. The front light further includes a point light source arranged at an end, in the longitudinal direction, of the second optical guide plate, and a reflective film covering the surfaces of the grooves.
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: October 21, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tomohiro Sasagawa, Kyoichiro Oda, Akimasa Yuuki, Naoto Sugawara, Masahiro Yokoi, Masahisa Moroda
  • Publication number: 20030156238
    Abstract: A transmissive display apparatus 21 comprises a liquid crystal display unit 22 and a plane light source unit 23. The unit 23 comprises a tubular light source 24, a light guide 25 having a wedge-shaped reflecting groove formed at the bottom thereof, and a light-diffusing film 27 having anisotropy and/or ultraviolet (UV) absorbability. In the film, a light-scattering characteristic F(&thgr;) representing the relationship between the light-scattering angle &thgr; and a scattered light intensity F fulfills Fy(&thgr;)/Fx(&thgr;)≧1.01 over a range of &thgr;=4 to 30°, wherein Fx(&thgr;) and Fy(&thgr;) represent the light-scattering characteristics in the X-axial direction and the Y-axial direction of the film, respectively. The film comprises a light-diffusing layer composed of a plurality of resins which are different from each other in refractive index, and a transparent layer laminated on at least one side thereof. The transparent layer at least may contain a UV absorber.
    Type: Application
    Filed: March 28, 2003
    Publication date: August 21, 2003
    Inventors: Masanori Hiraishi, Masanari Ohnishi, Tomohiro Sasagawa, Naoko Iwasaki, Akimasa Yuuki, Osamu Murakami
  • Patent number: 6573161
    Abstract: A fabrication process is provided for semiconductor devices having a crystalline semiconductor film formed on a substrate, the semiconductor film being an active layer of a transistor and being mainly composed of silicon, and includes at least an underlevel protection layer fabrication step of forming a silicon oxide film as an underlevel protection layer on the substrate; a first processing step of forming a semiconductor film, which is mainly composed of silicon, on the underlevel protection layer; and a second processing step of irradiating a pulsed laser light on the semiconductor film. The semiconductor film is irradiated by a pulsed laser, the wavelength of the pulsed laser light is between 370 and 710 nm. As a result, using a low temperature process, high performance thin film semiconductor devices can be produced simply and reliably.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: June 3, 2003
    Assignees: Seiko Epson Corporation, Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsutoshi Miyasaka, Tetsuya Ogawa, Hidetada Tokioka, Yukio Satoh, Mitsuo Inoue, Tomohiro Sasagawa
  • Patent number: 6566683
    Abstract: The laser heat treatment of an amorphous or polycrystalline silicon film material is conducted by forming a laser beam generated from a pulse laser source having a wavelength of 350 nm to 800 nm into a linear beam having a width and a length, and directing the linear beam onto a film material formed on a substrate.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: May 20, 2003
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Seiko Epson Corporation
    Inventors: Tetsuya Ogawa, Hidetada Tokioka, Yukio Sato, Mitsuo Inoue, Tomohiro Sasagawa, Mitsutoshi Miyasaka
  • Patent number: 6454452
    Abstract: A backlight provides uniform emanating light for a liquid crystal display. In the backlight, light emitted from a light source is incident on a receiving end surface of a light guide plate and emanates through a top surface toward a liquid crystal panel. A bottom surface includes a reflecting hollow wedge extending along the receiving end surface and varying in depth, as measured from the bottom surface, in correspondence with distance from the end surface. A dividing flat portion orthogonal to the reflecting hollow wedge divides the reflecting hollowed portion, and an output surface includes a prism having parallel ridges extending in a direction orthogonal to the receiving end surface.
    Type: Grant
    Filed: October 20, 2000
    Date of Patent: September 24, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tomohiro Sasagawa, Akimasa Yuuki, Naoko Iwasaki, Sadayuki Matsumoto, Mitsuo Inoue, Kyoichiro Oda
  • Patent number: 6437284
    Abstract: An optical system that controls laser beam spot profile for forming a high performance thin film by a laser heat treatment process is provided. In the optical system that irradiates a rectangular laser beam on a film formed on a substrate, intensity distribution forming, apparatus makes the intensity distribution uniform in the longitudinal direction while maintaining the properties of the laser beam 2 such as directivity in the direction of shorter side, making it possible to concentrate the light to a limit permitted by the nature of the laser beam and achieve the maximum intensity gradient on the film disposed on the substrate. Thus a steep temperature distribution can be generated on the film disposed on the substrate and, as a result, high performance thin film can be formed.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: August 20, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tatsuki Okamoto, Tetsuya Ogawa, Keisuke Furuta, Hidetada Tokioka, Tomohiro Sasagawa, Junichi Nishimae, Mitsuo Inoue, Yukio Sato
  • Publication number: 20020089698
    Abstract: An imaging apparatus including at least an imaging device having a plurality of photoelectric transfer devices arranged in matrix-shape to detect a light irradiated to each photoelectric transfer device and transfer to electric signal, and imaging means for imaging an image of a photogenic object on a surface of the imaging devices. The imaging means images at least two similar images of the photogenic subject on different area of the surface of the imaging device, and the imaging apparatus further includes electric signal processing means to form one image of photogenic subject from at least two images of photogenic subject. Since a plurality of images of photogenic subject can be formed on the imaging device by a plurality of image formation lenses, a thinner imaging apparatus can be realized.
    Type: Application
    Filed: January 9, 2001
    Publication date: July 11, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventors: Mitsuo Inoue, Tomohiro Sasagawa, Hiroaki Sugiura, Masao Hamamura
  • Publication number: 20020067447
    Abstract: A reflective liquid crystal display device having a structure which makes it possible to provide high contrast even if there is undesired light. The structure includes a light-guiding plate for receiving from a light-incident surface thereof light coming from a light source, and for allowing the light to exit from a bottom surface; a reflective liquid crystal display panel disposed so as to oppose the bottom surface of the light-guiding plate; and a prism disposed on the side of a top surface of an upper substrate of the liquid crystal display panel. The prism has a surface that is substantially perpendicular to the top surface of the upper substrate, and a tilted surface which is tilted towards a side opposite to the light source from a crest line of the substantially perpendicular surface at a tilt angle with respect to an imaginary surface which passes through the crest line of the substantially perpendicular surface and which is parallel to the top surface of the upper substrate.
    Type: Application
    Filed: October 3, 2001
    Publication date: June 6, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tomohiro Sasagawa, Akimasa Yuuki, Toshio Tobita
  • Publication number: 20010035927
    Abstract: A compact and light weight front light, a reflective liquid crystal display device and a personal digital assistant providing image display of uniform brightness with high efficiency are provided. The front light includes a main optical guide plate and a second optical guide plate. The second optical guide plate is arranged at an end portion of the main optical guide plate along the widthwise direction, and on an end surface opposite to an end surface facing the main optical guide plate, a plurality of prism- shaped grooves are formed along the longitudinal direction, extending in the depth direction. The front light further includes a point light source arranged at an end in the longitudinal direction of the second optical guide plate, and a reflective film covering the surface of the prism-shaped grooves.
    Type: Application
    Filed: March 29, 2001
    Publication date: November 1, 2001
    Inventors: Tomohiro Sasagawa, Kyoichiro Oda, Akimasa Yuuki, Naoto Sugawara, Masahiro Yokoi, Masahisa Moroda
  • Patent number: 6219116
    Abstract: A liquid crystal panel module includes a liquid crystal panel unit on a backlight unit. The backlight unit preferably has a holding member for holding the liquid crystal panel unit in a specific position on the backlight unit with no gap therebetween. Preferably, the backlight unit comprises a light guide; a lamp for emitting illumination from one side of the light guide; and a reflector for collecting light from the lamp on the light guide. The reflector has a polygonal cross section, a thickness greater than the thickness of the light guide, and is open to only the thickness of the light guide on the light guide side of the reflector.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: April 17, 2001
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Advanced Display Inc.
    Inventors: Akimasa Yuuki, Mitsumasa Umesaki, Sadayuki Matsumoto, Tomohiro Sasagawa, Sin Kawabe, Kazutoshi Shimojo
  • Patent number: 6147725
    Abstract: A liquid crystal panel module includes a backlight unit consisting of a light guide plate having a reflecting sheet at a lower face, a lamp for projecting light to one side of the light guide plate, a reflector for condensing the light from the lamp onto the light guide plate, and a liquid crystal panel having a polarizing plate at a lower face and disposed on the backlight unit. Equilateral prisms are located between the light guide plate and reflecting sheet of the backlight unit in a direction parallel to a polarization axis of the polarizing plate of the liquid crystal panel unit. Each of the prisms has a prism angle so that the angle of incidence of the light guided from the lamp into the light guide plate is the Brewster angle of the prisms.
    Type: Grant
    Filed: October 20, 1998
    Date of Patent: November 14, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akimasa Yuuki, Tomohiro Sasagawa
  • Patent number: 6110291
    Abstract: A thin film forming apparatus using laser includes a chamber (1), a target (5) placed therein, a laser light source (10) for emitting laser beam to target (5), and a substrate holder (3). When target (5) is irradiated with laser beam (16), a plume (15) is generated, and materials included in plume (15) are deposited on the surface of a substrate (2) held by substrate holder (3). The laser beam emitted from laser light source (10) has its cross section shaped to a desired shape when passed through a shielding plate (4804), for example, so that the surface of the target (5) is irradiated with the beam having uniform light intensity distribution. Therefore, a plume (15) having uniform density distribution of active particles is generated, and therefore a thin film of high quality can be formed over a wide area with uniform film quality, without damaging the substrate.
    Type: Grant
    Filed: August 7, 1996
    Date of Patent: August 29, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kenyu Haruta, Koichi Ono, Hitoshi Wakata, Mutsumi Tsuda, Yoshio Saito, Keisuke Nanba, Kazuyoshi Kojima, Tetsuya Takami, Akihiro Suzuki, Tomohiro Sasagawa, Kenichi Kuroda, Toshiyuki Oishi, Yukihiko Wada, Akihiko Furukawa, Yasuji Matsui, Akimasa Yuki, Takaaki Kawahara, Hideki Yabe, Taisuke Furukawa, Kouji Kise, Noboru Mikami, Tsuyoshi Horikawa, Tetsuo Makita, Kazuo Kuramoto, Naohiko Fujino, Hiroshi Kuroki, Tetsuo Ogama, Junji Tanimura