Patents by Inventor Tadaaki Nakayama

Tadaaki Nakayama 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: 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: 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: 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: 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: 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: 5626409
    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: January 4, 1995
    Date of Patent: May 6, 1997
    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