Patents by Inventor Yoshitaka Itoh

Yoshitaka Itoh 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: 6441710
    Abstract: A cold head is disposed in an insulating container and cooled by a refrigerator. A superconductor is disposed in the insulating container, contacting the cold head, and is cooled to its superconduction transition temperature or lower by heat conduction. A magnetizing coil is disposed outside the insulating container for applying a magnetic field to the superconductor. Control is performed so that a magnetic field determined considering the magnetic field to be captured by the superconductor is applied. A pulsed magnetic field is applied to the superconductor a plurality of times. Each pulsed magnetic field is applied when the temperature of the superconductor is a predetermined temperature or lower. A maximum pulsed magnetic field is applied at least once in an initial or intermediate stage of the repeated application of pulsed magnetic fields. After that, a pulsed magnetic field equal to or less than the maximum pulsed magnetic field is applied.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: August 27, 2002
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Yousuke Yanagi, Tetsuo Oka, Yoshitaka Itoh, Masaaki Yoshikawa
  • Publication number: 20020093737
    Abstract: A polarization luminaire is disclosed having a light source, a system of the optical integrator, a polarized light splitting device for splitting a light emitted from the light source into two kinds of polarized lights whose polarization directions are perpendicular to each other and whose traveling directions are apart from each other by an angle of less than 90 degrees, and a polarization conversion device for causing the two kinds of polarized lights to have the same polarization direction. The polarized light splitting device is placed on one of the entrance side and the outputting side of the first lens plate of the system of the optical integrator or is placed within the second lens plate. A prism beam splitter having a polarized light splitting film constituted by a thermally stable dielectric multi-layer film is suitable for the polarized light splitting device. Most of the polarized lights can be utilized by causing the polarized lights to have the same polarization direction.
    Type: Application
    Filed: March 18, 2002
    Publication date: July 18, 2002
    Applicant: Seiko Epson Corporation
    Inventors: Yoshitaka Itoh, Kunio Yoneno
  • Patent number: 6411438
    Abstract: A polarization luminaire is disclosed having a light source, a system of the optical integrator, a polarized light splitting device for splitting a light emitted from the light source into two kinds of polarized lights whose polarization directions are perpendicular to each other and whose traveling directions are apart from each other by an angle of less than 90 degrees, and a polarization conversion device for causing the two kinds of polarized lights to have the same polarization direction. The polarized light splitting device is placed on one of the entrance side and the outputting side of the first lens plate of the system of the optical integrator or is placed within the second lens plate. A prism beam splitter having a polarized light splitting film constituted by a thermally stable dielectric multi-layer film is suitable for the polarized light splitting device. Most of the polarized lights can be utilized by causing the polarized lights to have the same polarization direction.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: June 25, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Yoshitaka Itoh, Kunio Yoneno
  • Patent number: 6406016
    Abstract: A dispensing apparatus for thin flat articles, such as monetary currency bills, includes a plenum chamber having an aperture of a size smaller than the articles to be dispensed. A suction device is connected to the plenum chamber to provide sufficient negative pressure to adhere an article to the aperture. A contact member, such as an endless belt, is mounted for movement across the aperture to drive the article adhering to the aperture for release from the stack of articles. The stack of articles can be stored in a storage tray and biased towards the plenum chamber aperture. A series of spacer members can relieve part of the bias pressure. The released articles can be counted and stored in a storage chamber until a predetermined number of articles are accumulated. Subsequently, the passageway from the storage chamber to a dispenser tray can be opened and the articles ejected to the user.
    Type: Grant
    Filed: September 8, 1999
    Date of Patent: June 18, 2002
    Assignee: Asahi Seiko Co. Ltd.
    Inventors: Takashi Ehara, Kenichi Tezuka, Yoshitaka Itoh, Kenji Saito
  • Publication number: 20020070829
    Abstract: A cold head is disposed in an insulating container and cooled by a refrigerator. A superconductor is disposed in the insulating container, contacting the cold head, and is cooled to its superconduction transition temperature or lower by heat conduction. A magnetizing coil is disposed outside the insulating container for applying a magnetic field to the superconductor. Control is performed so that a magnetic field determined considering the magnetic field to be captured by the superconductor is applied. A pulsed magnetic field is applied to the superconductor a plurality of times. Each pulsed magnetic field is applied when the temperature of the superconductor is a predetermined temperature or lower. A maximum pulsed magnetic field is applied at least once in an initial or intermediate stage of the repeated application of pulsed magnetic fields. After that, a pulsed magnetic field equal to or less than the maximum pulsed magnetic field is applied.
    Type: Application
    Filed: February 6, 2002
    Publication date: June 13, 2002
    Applicant: AISIN SEIKI KABUSHIKI KAISHA
    Inventors: Yousuke Yanagi, Tetsuo Oka, Yoshitaka Itoh, Masaaki Yoshikawa
  • Patent number: 6394607
    Abstract: The invention provides a plate-shaped polarized light separation device that has a repetitive structure of polarized light separation film surfaces and reflective film surfaces arranged alternately at a fine pitch, along with a projection display apparatus that uses this polarized light separation device. In the process of manufacturing the polarized light separation device, first a glass block is formed by alternately pasting together plate glass with a polarized light separation film made up of a multi-layer thin film of inorganic material upon its surface and plate glass with a reflecting film upon its surface, and this glass block is cut obliquely to the pasted surfaces. A projection that is usable at the time of the positioning of the polarization beam splitter may be provided on at least one side of this plate-shaped block that is thus cut out.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: May 28, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Toshiaki Hashizume, Yoshitaka Itoh, Akitaka Yajima
  • Publication number: 20020057420
    Abstract: A projection-type display apparatus (1) is comprised of an illumination optical system (2A), a color separating system (4) for separating a white beam (W) from the illumination optical system into color beams (R, G, B), three liquid crystal panels (5R, 5G, 5B) for modulating the separated color beams, a light guide system (9) located on an optical path of the beam (G) having the longest optical path among the separated color beams respectively incident on the three light valves, a dichroic prism (6) for synthesizing the beams modulated through the liquid crystal panels, and a projection lens (7) for projecting the synthesized and modulated beam onto a screen (8). The illumination optical system (2A) is provided with a uniform illumination optical device (3) for converting the white beam into a uniform rectangular beam.
    Type: Application
    Filed: October 30, 2001
    Publication date: May 16, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tadaaki Nakayama, Yoshitaka Itoh, Akitaka Yajima
  • Patent number: 6348997
    Abstract: The invention provides a polarizing illumination device in which randomly polarized light beams emitted from first and second light source sections, respectively, are directionally separated into two types of polarized light beams by a polarization separating optical element to form three types of polarization light beams whose directions of polarization mutually intersect perpendicularly, and then, one of the polarized light beam is returned to the light source sections to rotate the direction of polarization, other two types of polarized light beams are condensed at spatially different positions, and the directions of polarization of the polarized light beams are unified. Therefore, a polarizing illumination device that is able to utilize both polarized light components by using a plurality of light sources without increasing the illumination angle can be provided, and a projector that is able to project an extremely bright projection image can also be provided.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: February 19, 2002
    Assignee: Seiko Epson Corporation
    Inventor: Yoshitaka Itoh
  • Patent number: 6348996
    Abstract: The invention provides a polarizing illumination device in which randomly polarized lights emitted from first and second light source sections, respectively, are directionally separated into two types of polarized lights by a polarization-separating-and-synthesizing optical element, and then, secondary light source images, which are offset in the x direction, are formed and the direction of polarization is unified.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: February 19, 2002
    Assignee: Seiko Epson Corporation
    Inventor: Yoshitaka Itoh
  • Patent number: 6344927
    Abstract: A polarization luminaire is disclosed having a light source, a system of the optical integrator, a polarized light splitting device for splitting a light emitted from the light source into two kinds of polarized lights whose polarization directions are perpendicular to each other and whose traveling directions are apart from each other by an angle of less than 90 degrees, and a polarization conversion device for causing the two kinds of polarized lights to have the same polarization direction. The polarized light splitting device is placed on one of the entrance side and the outputting side of the first lens plate of the system of the optical integrator or is placed within the second lens plate. A prism beam splitter having a polarized light splitting film constituted by a thermally stable dielectric multi-layer film is suitable for the polarized light splitting device. Most of the polarized lights can be utilized by causing the polarized lights to have the same polarization direction.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: February 5, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Yoshitaka Itoh, Kunio Yoneno, Junichi Nakamura, Tadaaki Nakayama
  • Patent number: 6341867
    Abstract: In a polarized light illumination apparatus, randomly polarized lights emitted from first and second light sources are respectively separated by a polarized light separating and combining element into two different types of polarized lights. Secondary light source images are formed at locations shifted from each other in an x direction, whereby polarization is aligned in the same single direction. At least two condensing mirror plates of first to third condensing mirror plates are shifted in parallel from the center axis of the polarized light separating and combining optical element so that secondary light source images formed by z-polarized lights (polarized in a z direction) emitted from the first and second light sources are superimposed upon each other, and secondary light source images formed by x-polarized lights (polarized in an x direction) emitted from the first and second light sources are superimposed upon each other.
    Type: Grant
    Filed: August 12, 1999
    Date of Patent: January 29, 2002
    Assignee: Seiko Epson Corporation
    Inventor: Yoshitaka Itoh
  • Patent number: 6310723
    Abstract: A polarization luminaire is disclosed having a light source, a system of the optical integrator, a polarized light splitting device for splitting a light emitted from the light source into two kinds of polarized lights whose polarization directions are perpendicular to each other and whose traveling directions are apart from each other by an angle of less than 90 degrees, and a polarization conversion device for causing the two kinds of polarized lights to have the same polarization direction. The polarized light splitting device is placed on one of the entrance side and the outputting side of the first lens plate of the system of the optical integrator or is placed within the second lens plate. A prism beam splitter having a polarized light splitting film constituted by a thermally stable dielectric multi-layer film is suitable for the polarized light splitting device. Most of the polarized lights can be utilized by causing the polarized lights to have the same polarization direction.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: October 30, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Yoshitaka Itoh, Junichi Nakamura
  • Patent number: 6309073
    Abstract: A projection-type display apparatus includes a light source, a uniform illumination optical system, a color separating system for separating a white light beam emitted from the uniform illumination optical system into three color beams, three liquid crystal panels for respectively modulating each of the separated color beams, a light guide system located on an optical path of the color beam having the longest optical path among the separated color beams, a dichroic prism for synthesizing the beams modulated through the liquid crystal panels, and a projection lens for projecting the synthesized and modulated beam onto a screen. The uniform illumination optical system is provided with a uniform illumination optical device for converting the white light beam emitted from the light source into a uniform beam.
    Type: Grant
    Filed: March 16, 2000
    Date of Patent: October 30, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Tadaaki Nakayama, Yoshitaka Itoh, Akitaka Yajima
  • Patent number: 6208451
    Abstract: A polarization conversion system comprises a polarized light selective reflector that divides incident unpolarized light into first and second types of polarized light, transmits the first type of polarized light and reflects the second type of polarized light, a relay optical system that relays an incident light beam onto the polarized light selective reflector, a polarized light reflector, disposed on an optical path of a reflected light beam reflected by the polarized light selective reflector, that reflect the reflected light beam back to the polarized light selective reflector while converting the second type of polarized light to polarized light of the first type.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: March 27, 2001
    Assignee: Seiko Epson Corporation
    Inventor: Yoshitaka Itoh
  • Patent number: 6204972
    Abstract: An upper portion and lower portion of a first lens array may be relatively offset from each other in an x direction. A second lens array is also offset correspondingly to the first lens array. Since an angle at which a partial light beam transmitted through the upper portions of the first and second lens arrays illuminates an area of illumination is different from an angle at which a partial light beam transmitted through the lower portions of the first and second lens arrays illuminates the area of illumination, dark lines generated by these partial light beams appear in different positions on a screen. With this arrangement, the dark lines resulting from the center line of a cross-dichroic prism are made less visible.
    Type: Grant
    Filed: February 17, 2000
    Date of Patent: March 20, 2001
    Assignee: Seiko Epson Corporation
    Inventor: Yoshitaka Itoh
  • Patent number: 6154320
    Abstract: A polarizing conversion device in accordance with the invention includes a first optical element for condensing an incident beam and forming a plurality of intermediate beams spatially separated from one another, and a second optical element for spatially separating each intermediate beam into two polarized beams and aligning the polarization directions of the polarized beams, thereby obtaining the same type of polarized beams. In the second optical element, a shading plate is placed to prevent light from directly entering a section corresponding to a reflecting plane of a polarizing separation unit array. Since the ability of separating the intermediate beam into two polarized beams is thereby enhanced, it is possible to perform conversion into the same type of polarized beams polarized in the same direction, with high efficiency.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: November 28, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Yoshitaka Itoh, Toshiaki Hashizume
  • Patent number: 6147802
    Abstract: A polarization luminaire of the present invention has a light source, an optical integrator, a polarized light splitting means and a polarization conversion means. The polarized light splitting means splits a light emitted from the light source into two kinds of polarized lights. The polarization directions of the two kinds of polarized lights are perpendicular to each other and travel in directions separated by an angle of less than 90 degrees. The polarization conversion means modifies the two kinds of polarized lights to have the same polarization direction. The polarized light splitting means is placed on the entrance side or the outputting side of a first lens plate of the optical integrator, or is placed within a second lens plate. A prism beam splitter having a polarized light splitting film that includes a thermally stable dielectric multi-layer film may be used as the polarized light splitting means.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: November 14, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Yoshitaka Itoh, Kunio Yoneno, Junichi Nakamura, Tadaaki Nakayama
  • Patent number: 6132047
    Abstract: In a polarized light illumination apparatus, randomly polarized lights emitted from first and second light sources are respectively separated by a polarized light separating optical element into two different types of polarized light thereby producing three types of polarized light which are polarized in directions perpendicular to one another. The polarized lights are partially returned to the light sources and their polarization directions are rotated. Secondary light source images are formed at locations shifted in an x direction whereby polarization is aligned in the same single direction. Thus, even though a plurality of light sources are used, the polarized light illumination apparatus can emit illumination light using both polarized components without causing an increase in the illumination angle. Furthermore, a projector capable of projecting an image with a very high brightness can be realized.
    Type: Grant
    Filed: August 12, 1999
    Date of Patent: October 17, 2000
    Assignee: Seiko Epson Corporation
    Inventor: Yoshitaka Itoh
  • Patent number: 6120152
    Abstract: A projection-type display apparatus includes a light source, a uniform illumination optical system, a color separating system for separating a white light beam emitted from the uniform illumination optical system into three color beams, three liquid crystal panels for respectively modulating each of the separated color beams, a light guide system located on an optical path of the color beam having the longest optical path among the separated color beams, a dichroic prism for synthesizing the beams modulated through the liquid crystal panels, and a projection lens for projecting the synthesized and modulated beam onto a screen. The uniform illumination optical system is provided with a uniform illumination optical device for converting the white light beam emitted from the light source into a uniform beam.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: September 19, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Tadaaki Nakayama, Yoshitaka Itoh, Akitaka Yajima
  • Patent number: RE36850
    Abstract: A projection-type display apparatus includes a light source, a uniform illumination optical system, a color separating system for separating a white light beam emitted from the uniform illumination optical system into three color beams, three liquid crystal panels for respectively modulating each of the separated color beams, a light guide system located on an optical path of the color beam having the longest optical path among the separated color beams, a dichroic prism for synthesizing the beams modulated through the liquid crystal panels, and a projection lens for projecting the synthesized and modulated beam onto a screen. The uniform illumination optical system Is provided with a uniform illumination optical device for converting the white light beam emitted from the light source into a uniform rectangular beam.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: September 5, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Tadaaki Nakayama, Yoshitaka Itoh, Akitaka Yajima