Patents by Inventor Joji Karasawa

Joji Karasawa 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: 7156523
    Abstract: Aspects of the invention can provide a projector can include an illumination device that outputs illumination light, a color separation system that divides the illumination light output from the illumination device into blue light, red light, and green light and guides the blue light, red light, and green light to first to third optical paths, respectively, and first to third light modulation devices disposed in the first to third optical paths to be illuminated by the blue light, red light, and green light. In the projector, a distance from the illumination device to the third optical modulation device can be longer than a distance from the illumination device to the first optical modulation device and a distance from the illumination device to the second optical modulation device, a relay system having a first lens disposed at the light incident side, a second lens disposed at the light exit side, and a third lens disposed between the first and second lenses can be provided in the third optical path.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: January 2, 2007
    Assignee: Seiko Epson Corporation
    Inventors: Hidemasa Yamakawa, Joji Karasawa, Masafumi Sakaguchi, Kanji Yoshida
  • Publication number: 20060077357
    Abstract: Aspects of the invention can provide a projector that includes three optical modulators which modulate respectively red light, green light, and blue light, a color-synthetic optical system which synthesizes the light modulated by the three optical modulators, and a projection optical system which projects the light synthesized by the color-synthetic optical system. The color-synthetic optical system can include a first reflection film that reflects the green light, and a second reflection film that reflects the blue light, the first reflection film and the second reflection film are arranged in the shape of an X character, and a wavelength in which a reflectance factor of the first reflection film comes to 50% can be longer than a wavelength in which a reflectance factor of the second reflection film comes to 50%.
    Type: Application
    Filed: October 5, 2005
    Publication date: April 13, 2006
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kanji Yoshida, Hidemasa Yamakawa, Joji Karasawa, Masafumi Sakaguchi
  • Publication number: 20060072209
    Abstract: Aspects of the invention can provide a projector that can include an illumination device that emits an illumination light, a color separation system that separates the illumination light emitted from the illumination device into a blue light, a red light, and a green light, and guides the blue light and the red light, respectively, to first and second optical paths, and the green light to a third optical path in which a relay system is provided, first through third light modulation devices that are provided, respectively, in the first through third optical paths, and illuminated by the blue light, the red light, and the green light, respectively, a light combining system that can have a first dichroic filter reflecting one of the blue light and the red light, and a second dichroic filter reflecting the green light which are placed in a crossed state, and that can combine image lights of respective colors exiting from the first through third light modulation devices to go incident on the first and second dichr
    Type: Application
    Filed: October 5, 2005
    Publication date: April 6, 2006
    Applicant: Seiko Epson Corporation
    Inventors: Joji Karasawa, Hidemasa Yamakawa, Kanji Yoshida, Masafumi Sakaguchi
  • Publication number: 20060050396
    Abstract: Aspects of the invention can provide a projector can include an illumination device that outputs illumination light, a color separation system that divides the illumination light output from the illumination device into blue light, red light, and green light and guides the blue light, red light, and green light to first to third optical paths, respectively, and first to third light modulation devices disposed in the first to third optical paths to be illuminated by the blue light, red light, and green light. In the projector, a distance from the illumination device to the third optical modulation device can be longer than a distance from the illumination device to the first optical modulation device and a distance from the illumination device to the second optical modulation device, a relay system having a first lens disposed at the light incident side, a second lens disposed at the light exit side, and a third lens disposed between the first and second lenses can be provided in the third optical path.
    Type: Application
    Filed: September 6, 2005
    Publication date: March 9, 2006
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hidemasa Yamakawa, Joji Karasawa, Masafumi Sakaguchi, Kanji Yoshida
  • Publication number: 20060007399
    Abstract: To provide a thin projector, such as a rear projector, formed by a less expensive projection optical system which is easy to assemble and install, and performing a highly accurate projection, projection light PL projected with a projection optical system onto a screen is linearly polarized light having a polarization azimuth along the longitudinal direction of the screen. With this arrangement, the right and left ends of the rear surface of the screen maintain a low reflectance, thereby reducing a loss in quantity of illumination light when passing through the screen, in other words, achieving high luminance of an image projected onto the screen while maintaining its uniformity of brightness.
    Type: Application
    Filed: September 9, 2005
    Publication date: January 12, 2006
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Joji Karasawa
  • Patent number: 6947212
    Abstract: The invention provides a transmissive screen that can be manufactured at a low cost and show uniform diffusion and moire-free images over the entire screen, and provides a rear projector provided with such a superior transmissive screen. A transmissive screen can include a Fresnel lens portion having Fresnel-lens components on its light-exiting face and a lens array facing the light-exiting face of the Fresnel lens portion and having many lenses on its light-incident face. The transmissive screen can further include separating device for separating the Fresnel lens portion from the lens array portion at least in the periphery of the screen. Such a superior transmissive screen can be included in a rear projector.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: September 20, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Joji Karasawa, Masafumi Sakaguchi
  • Publication number: 20050128439
    Abstract: To provide a projector that hardly causes deterioration of an image resulted from stray light. A neutral density filter, of which posture can be fine-adjusted by a posture regulating mechanism, is placed in a space between a second dichroic mirror and a liquid crystal light valve. Thus, it is possible to remove stray light, corresponding to condensed light resulted from multi-pass through a field lens or the like, to the outside of a light path by merely tilting the neutral density filter adequately. It is thus possible to project an image having homogeneous brightness (illuminance at the white level) across the entire screen, which in turn makes it possible to project an image having no irregularities in color across the entire screen.
    Type: Application
    Filed: November 4, 2004
    Publication date: June 16, 2005
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kanji Yoshida, Joji Karasawa
  • Publication number: 20040212782
    Abstract: To provide a thin projector, such as a rear projector, formed by a less expensive projection optical system which is easy to assemble and install, and performing a highly accurate projection, projection light PL projected with a projection optical system onto a screen is linearly polarized light having a polarization azimuth along the longitudinal direction of the screen. With this arrangement, the right and left ends of the rear surface of the screen maintain a low reflectance, thereby reducing a loss in quantity of illumination light when passing through the screen, in other words, achieving high luminance of an image projected onto the screen while maintaining its. uniformity of brightness.
    Type: Application
    Filed: March 22, 2004
    Publication date: October 28, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Joji Karasawa
  • Publication number: 20040070845
    Abstract: To provide a transmissive screen that can be manufactured at a low cost and show uniform diffusion and moire-free images over the entire screen, and to provide a rear projector provided with such a superior transmissive screen. A transmissive screen includes a Fresnel lens portion having Fresnel-lens components on its light-exiting face and a lens array facing the light-exiting face of the Fresnel lens portion and having many lenses on its light-incident face. The transmissive screen further includes separating means for separating the Fresnel lens portion from the lens array portion at least in the periphery of the screen. A rear projector includes such a superior transmissive screen.
    Type: Application
    Filed: August 22, 2003
    Publication date: April 15, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Joji Karasawa, Masafumi Sakaguchi
  • Patent number: 6538624
    Abstract: In a head-mounted image display apparatus (1) for viewing images on a liquid crystal display means virtually enlarged by an enlarging lens while worn on the head, main apparatus (10) comprises a front case (2), which is positioned at the frontal region side when said main apparatus is worn on the head, and a back case (3), which is positioned at the occipital region. In addition, an air bag (8), which inflates to cause the frontal region to contact a buffer pad affixed to the inside surface of the front case (2), is provided on the inside of the back case (3). The back case (3) is able to rotate on connecting member 5 to the front case (2). Adjustment mechanisms for moving the optical system in the pupil distance direction and in the direction of the optical axes is disposed inside main apparatus (10), and the knobs therefor are centrally disposed on the front of main apparatus (10).
    Type: Grant
    Filed: April 12, 2000
    Date of Patent: March 25, 2003
    Assignee: Seiko Epson Corporation
    Inventors: Joji Karasawa, Shoichi Ishizawa, Shoichi Uchiyama, Yoko Miyazawa
  • Patent number: 6491396
    Abstract: The invention relates to methods and systems that suppress the expansion of an illuminating luminous flux in the short-side direction of a sub-pixel and prevents a color mixture caused by leak of light to an adjacent pixel electrode. The methods and systems of the invention set the direction of polarization separation, using a polarization transforming element, as the long-side direction of a sub-pixel with respect to the directions of the short sides and the long sides of sub-pixels arranged correspondingly to a microlens. The methods and systems of the invention also make the intervals between light source images narrower in the short-side direction, using a luminous flux separation optical element.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: December 10, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Joji Karasawa, Yoshitaka Ito
  • Publication number: 20020126066
    Abstract: A head-mounted image display device with a good operability and a data processing apparatus including such a display device. A head-mounted image display device wherein a liquid crystal panel and an enlarging optical system are crystal display panel through the enlarging optical system housed in a frame and wherein images generated on the liquid are visible in the field of view in front of the frame comprises a first direction detection means (107) disposed in part of the frame (101) for detecting the direction of the user's head; an observation point detection means (109) disposed in part of the frame for detecting the user's line of sight; a trigger input means (4) for transmitting trigger signals; and an image generation means (3, 105) for controlling images generated on the liquid crystal display panel based on signals from the first direction detection, observation point detection, and trigger input means.
    Type: Application
    Filed: August 13, 2001
    Publication date: September 12, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Masaaki Yasukawa, Tadashi Kinebuchi, Noriko Watanabe, Kunio Yoneno, Syoichi Uchiyama, Hiroshi Kamakura, Joji Karasawa
  • Patent number: 6320559
    Abstract: A head-mounted image display device with a good operability and a data processing apparatus including such a display device. A head-mounted image display device wherein a liquid crystal panel and an enlarging optical system are housed in a frame and wherein images generated on the liquid crystal display panel through the enlarging optical system are visible in the field of view in front of the frame comprises a first direction detection means (107) disposed in part of the frame (101) for detecting the direction of the user's head; an observation point detection means (109) disposed in part of the frame for detecting the user's line of sight; a trigger input means (4) for transmitting trigger signals; and an image generation means (3, 105) for controlling images generated on the liquid crystal display panel based on signals from the first direction detection, observation point detection, and trigger input means.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: November 20, 2001
    Assignee: Seiko Epson Corporation
    Inventors: Masaaki Yasukawa, Tadashi Kinebuchi, Noriko Watanabe, Kunio Yoneno, Syoichi Uchiyama, Hiroshi Kamakura, Joji Karasawa
  • Publication number: 20010033367
    Abstract: The invention suppresses the expansion of an illuminating luminous flux in the short-side direction of a sub-pixel and prevents a color mixture caused by leak of light to an adjacent pixel electrode by setting the direction of polarization separation by the polarization transforming element 40 as the long-side direction of a sub-pixel with respect to the directions of the short sides and the long sides of sub-pixels arranged correspondingly to a microlens and making the intervals between the light source images by the luminous flux separation optical element 20 more narrow in the short-side direction.
    Type: Application
    Filed: February 14, 2001
    Publication date: October 25, 2001
    Applicant: Seiko Epson Corporation
    Inventors: Joji Karasawa, Yoshitaka Ito
  • Patent number: 6040945
    Abstract: An optical unit 1 includes a liquid crystal panel 2, a back light 3, a reflecting mirror 4, a lens 5, and a casing 6 for accommodating these constituents therein. The optical unit 1 can be arranged in front of either the left eye or the right eye of the user. A half mirror 8 disposed below the optical unit 1 reflects an image beam emitted from the optical unit 1 toward an eye 10 of the user and transmits a light beam from the background view. The eye of the user which observes a virtual image is changed by shifting the optical unit 1 to the left eye or to the right eye.
    Type: Grant
    Filed: January 25, 1999
    Date of Patent: March 21, 2000
    Assignee: Seiko Epson Corporation
    Inventor: Joji Karasawa
  • Patent number: 6011653
    Abstract: An optical unit 1 includes a liquid crystal panel 2, a back light 3, a reflecting mirror 4, a lens 5, and a casing 6 for accommodating these constituents therein. The optical unit 1 can be arranged in front of either the left eye or the right eye of the user. A half mirror 8 disposed below the optical unit 1 reflects an image beam emitted from the optical unit 1 toward an eye 10 of the user and transmits a light beam from the background view. The eye of the user which observes a virtual image is changed by shifting the optical unit 1 to the left eye or to the right eye.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: January 4, 2000
    Assignee: Seiko Epson Corporation
    Inventor: Joji Karasawa
  • Patent number: 5977935
    Abstract: A head-mounted image display device with a good operability and a data processing apparatus including such a display device. A head-mounted image display device wherein a liquid crystal panel and an enlarging optical system are housed in a frame and wherein images generated on the liquid crystal display panel through the enlarging optical system are visible in the field of view in front of the frame comprises a first direction detection means (107) disposed in part of the frame (101) for detecting the direction of the user's head; an observation point detection means (109) disposed in part of the frame for detecting the user's line of sight; a trigger input means (4) for transmitting trigger signals; and an image generation means (3, 105) for controlling images generated on the liquid crystal display panel based on signals from the first direction detection, observation point detection, and trigger input means.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: November 2, 1999
    Assignee: Seiko Epson Corporation
    Inventors: Masaaki Yasukawa, Tadashi Kinebuchi, Noriko Watanabe, Kunio Yoneno, Syoichi Uchiyama, Hiroshi Kamakura, Joji Karasawa
  • Patent number: 5739893
    Abstract: In a head-mounted image display apparatus (1) for viewing images on a liquid crystal display means virtually enlarged by an enlarging lens while worn on the head, main apparatus (10) comprises a front case (2), which is positioned at the frontal region side when said main apparatus is worn on the head, and a back case (3), which is positioned at the occipital region. In addition, an air bag (8), which inflates to cause the frontal region to contact a buffer pad affixed to the inside surface of the front case (2), is provided on the inside of the back case (3). The back case (3) is able to rotate on connecting member 5 to the front case (2). Adjustment mechanisms for moving the optical system in the pupil distance direction and in the direction of the optical axes is disposed inside main apparatus (10), and the knobs therefor are centrally disposed on the front of main apparatus (10).
    Type: Grant
    Filed: June 22, 1995
    Date of Patent: April 14, 1998
    Assignee: Seiko Epson Corporation
    Inventors: Joji Karasawa, Shoichi Ishizawa, Shoichi Uchiyama, Yoko Miyazawa
  • Patent number: 5739797
    Abstract: A head-mounted display device for enlarging an image formed by an image display element as a virtual image. The head-mounted display device according to this invention comprises a virtual image forming optical system (3) including an image display element (9) and a lens (11) for enlarging an image formed by the image display element (9); a device main body (1) that houses the image forming optical means (3); and a switching means mounted in the device main body (1) for holding the virtual image forming optical system (3) in such a way that the system (3) can be moved in the direction of the width of the eye and placing the virtual image forming optical system (3) in front of one of the user's eyes. The image display element (9) and the lens (11) are disposed so that the optical axis of the virtual image forming optical system (3) approximately aligns with the user's line of sight taken while he or she is looking horizontally.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: April 14, 1998
    Assignee: Seiko Epson Corporation
    Inventors: Joji Karasawa, Hiroshi Kamakura, Shoichi Uchiyama, Hiroyuki Shindo, Takeshi Furihata, Masafumi Sakaguchi
  • Patent number: D363279
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: October 17, 1995
    Assignee: Seiko Epson Corporation
    Inventors: Shoichi Ishizawa, Joji Karasawa