Liquid Crystal Patents (Class 348/751)
  • Patent number: 5614962
    Abstract: In a projection-type display apparatus using light scattering type liquid crystal devices, light from a light source is reflected by a reflecting mirror through a collecting lens; reflected light is converted by a lens into a parallel light beam, which is injected into liquid crystal devices disposed on three sides through a dichroic mirror, the liquid crystal devices coloring an image in red, green and blue; the image is projected on a screen through again the dichroic mirror, the collecting lens and an enlarging lens. Further a photodetector is disposed at a focal point of the collecting lens and a function of adjusting the position of the light source on the basis of a result of this detection is added.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: March 25, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Yoshiharu Nagae, Yuji Mori, Yoshiro Mikami, Hideo Sato, Minoru Hoshino, Kyohei Fukuda
  • Patent number: 5608467
    Abstract: A color projection video system utilizing only a single light valve. A white light source is separated into into red, green and blue bands. Scanning optics cause the RGB bands to be sequentially scanned across a light valve, such as a transmission LCD panel. Prior to each color passing over a given row of panels on the light valve, that row will be addressed, by the display electronics with the appropriate color content of that portion of the image which is being displayed. The image is projected by a projection lens onto a viewing surface, such as a screen. The sequence of light bands occurs so quickly as to give the viewer an appearance of simultaneous full color.
    Type: Grant
    Filed: July 18, 1995
    Date of Patent: March 4, 1997
    Assignee: Philips Electronics North America Corporation
    Inventors: Peter J. Janssen, Ralph H. Bradley, Joseph P. Bingham, William F. Guerinot, Detlev Otto
  • Patent number: 5555035
    Abstract: Projection apparatus comprising high resolution projection display systems that generate a relatively large high resolution image on a display screen, wherein seams and tiling artifacts in observation (image) space are eliminated or minimized. The projection apparatus comprises an image source that includes a plurality of small tiled image displays, relay optics, and a photoactivated reflective liquid crystal light valve. The small tiled or mosaic-like displays that provide source images that are displayed. The images projected by the image displays are imaged onto the light valve. A polarizing beamsplitter is disposed adjacent an output surface of the light valve, and an illumination source provides illumination light that is projected by way of the polarizing beamsplitter onto an output surface of the light valve. The illumination light is reflected from the output surface of the light valve back through the polarizing beamsplitter. A projection lens projects the illumination light onto the display screen.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: September 10, 1996
    Assignee: Hughes Aircraft Company
    Inventors: Donald C. Mead, Ronald S. Gold, Victor J. Fritz
  • Patent number: 5552840
    Abstract: The present invention relates to a projection type liquid crystal display. In a preferred aspect, the projection type liquid crystal display of the invention includes an optical source for generating light, a light dividing unit which divides the light into a first light having a first polarization direction and a second polarization direction and allows the first and second lights to come out in different directions from each other, a pair of reflective liquid crystal display elements formed of a first reflective liquid crystal display element and a second reflective liquid crystal display element with synchronization, a light synthesizing unit for receiving the first light which comes out of the first reflective liquid crystal display element and the second light which comes out of the second reflective liquid crystal display element and synthesizing the first and second lights into image light, and a screen.
    Type: Grant
    Filed: March 11, 1993
    Date of Patent: September 3, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yutaka Ishii, Yoshitaka Yamamoto
  • Patent number: 5532763
    Abstract: A color projection video system utilizing only a single light valve. A white light source is separated into into red, green and blue bands. Scanning optics cause the RGB bands to be sequentially scanned across a light valve, such as a transmission LCD panel. Prior to each color passing over a given row of panels on the light valve, that row will be addressed, by the display electronics with the appropriate color content of that portion of the image which is being displayed. The image is projected by a projection lens onto a viewing surface, such as a screen. The sequence of light bands occurs so quickly as to give the viewer an appearance of simultaneous full color.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: July 2, 1996
    Assignee: North American Philips Corporation
    Inventors: Peter J. Janssen, Ralph H. Bradley, Joseph P. Bingham, William F. Guerinot, Detlev Otto
  • Patent number: 5526063
    Abstract: A three-color image projector, of the type using several colored light beams with primary colors, with improved luminous efficiency. The projector employs spatial rather than temporal beam modulation. The projector includes a generator producing light in the three spectral bands corresponding to the primary colors (red, green, blue). The generator has at least two light sources (S1, S2), one of which produces multi-spectral band light, and the other is a monochromatic source. By comparison with the prior art, where the white light is produced by a single source, this arrangement avoids, in particular, the elimination of a significant quantity of lumens in the excess primary color.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: June 11, 1996
    Assignee: Thomson-CSF
    Inventors: Cecile Joubert, Claude Puech, Brigitte Loiseaux, Jean-Pierre Huignard
  • Patent number: 5499061
    Abstract: A projection system for pictures and a projection display apparatus which are designed to improve the luminance and contrast of a magnified picture on a projection screen by increasing the luminous flux projected within the effective size of projection optical systems. The projection display apparatus has a picture compressions device for compressing the aspect ratio of the source picture formed on the face plate panel (PNL) of a projection cathode-ray tube (PRT) or a liquid crystal panel (LCP) to make it substantially 1 and an optical system for extending a picture (EXT) for extending the source picture having the same aspect ratio as that of the original picture. With this construction, the whole luminous flux passing the effective size of the projection optical system is maximized with the effect of improving the luminance and contrast of the magnified pictured projected onto the projection screen.
    Type: Grant
    Filed: January 24, 1995
    Date of Patent: March 12, 1996
    Assignee: Hitachi, Ltd.
    Inventor: Kentaro Oku
  • Patent number: 5488436
    Abstract: A liquid crystal projector which splits white light projected from a light source and light-intensity-modulates and synthesizes the split light components to project the synthesized light components onto a screen. The projector includes a dichroic mirror having a light transmittance characteristic in which two color light components of the three color light components being adjacent in spectrum are transmitted, and a dichroic mirror having a light transmittance characteristic in which the remaining color light excluding the two color light components is reflected. The location of the light source is appropriately modified inside the projector. Accordingly, the production cost is reduced, the heat produced by the light source is not exhausted toward the viewers and the projector is miniaturized.
    Type: Grant
    Filed: April 20, 1993
    Date of Patent: January 30, 1996
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Soon C. Choi, Ki U. Jeon
  • Patent number: 5481320
    Abstract: An electro-optical device includes a light amplifying portion comprising a first substrate having a transparent conductive film, a photoconductor whose electric resistance is lowered in accordance with light irradiation and a dielectric thin film, a second substrate having a transparent conductive film and uniaxially-orienting layer and a ferroelectric liquid crystal or antiferroelectric liquid crystal layer sandwiched between the first and second substrate, an image write-in portion comprising a display body, a mirror for splitting an image light into three color lights and light shutters for performing a switching operation between transmission and interception of the split lights, and serves to irradiate the image light through the first substrate of each light amplifying portion, an image read-out portion comprising a light source for irradiating light through the second substrate of each of the three light amplifying portions, and red, green and blue color filter portions, and an imaging portion for synt
    Type: Grant
    Filed: July 13, 1992
    Date of Patent: January 2, 1996
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Toshimitsu Konuma, Akira Mase
  • Patent number: 5477280
    Abstract: A liquid crystal projector has a video monitor for displaying the same image as that displayed on a screen. The video monitor uses an amount of the light which is not displayed on the front screen according to the light transmission characteristic of a dichroic mirror, to thereby enable a user to view the same image as that displayed on the front screen through a projection lens.
    Type: Grant
    Filed: June 9, 1994
    Date of Patent: December 19, 1995
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Han-il Ko
  • Patent number: 5404175
    Abstract: In a projection-type display apparatus using light scattering type liquid crystal devices, light from a light source is reflected by a reflecting mirror through a collecting lens; reflected light is converted by a lens into a parallel light beam, which is injected into liquid crystal devices disposed on three sides through a dichroic mirror, the liquid crystal devices coloring an image in red, green and blue; the image is projected on a screen through again the dichroic mirror, the collecting lens and an enlarging lens. Further a photodetector is disposed at a focal point of the collecting lens and a function of adjusting the position of the light source on the basis of a result of this detection is added.
    Type: Grant
    Filed: March 18, 1992
    Date of Patent: April 4, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Yoshiharu Nagae, Yuji Mori, Yoshiro Mikami, Hideo Sato, Minoru Hoshino, Kyohei Fukuda
  • Patent number: 5386252
    Abstract: A projection system for pictures and a projection display apparatus which are designed to improve the luminance and contrast of a magnified picture on a projection screen by increasing the luminous flux projected within the effective size of projection optical systems. The projection display apparatus has a picture compression device for compressing the aspect ratio of the source picture formed on the face plate panel (PNL) of a projection cathode-ray tube (PRT) or a liquid crystal panel (LCP) to make it substantially 1 and an optical system for extending a picture (EXT) for extending the source picture having the same aspect ratio as that of the original picture. With this construction, the whole luminous flux passing the effective size of the projection optical system is maximized with the effect of improving the luminance and contrast of the magnified pictured projected onto the projection screen.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: January 31, 1995
    Assignee: Hitachi, Ltd.
    Inventor: Kentaro Oku
  • Patent number: 5357289
    Abstract: This specification discloses an image projector for projecting a tri-color composite optical image on a screen as a magnified optical image. A reading light beam emitted from a light source is separated into three color beams, e.g., Red, Green and Blue color beams through a tri-color separation and composition optical system. The separated color beams are irradiated on image forming devices provided correspondingly with Red, Green and Blue color images to read out color images respectively therefrom. Each of the reflected light beams from the image forming device carrying color image information impinges again on the tri-color separation and composition optical system to compose a composite image beam. The composite image beam is projected on the screen through an optical lens system comprising a first lens group, a second lens group and a third lens group disposed along an optical axis in order.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: October 18, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ighiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5327229
    Abstract: A clear color image having a high contrast ratio without particular coloration is displayed on a screen by improved display apparatus. Such display apparatus is comprised of a spatial light modulator including a photo-conductive layer, a photo-modulator layer and a dielectric mirror, a device for writing color images of different colors onto the spatial light modulator time-divisionally in a sequence of the different colors, a reading device for producing reading lights having different colors in synchronism with time-divisional writing of the color images, and for projecting the reading lights to the spatial light modulator, a driving device for supplying the spatial light modulator with different voltages and frequencies correspondingly with the reading light of different colors and in synchronism with time-divisional projections of the reading lights, and a device for projecting the color images read out from the spatial light modulator on the display device.
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: July 5, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Toshio Konno, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Hiroyuki Bonde, Tsutomu Matsumura
  • Patent number: 5317409
    Abstract: A diagonally oriented LCD panel is used in a rear screen LCD projection television to reduce moire fringes on the display.
    Type: Grant
    Filed: December 3, 1991
    Date of Patent: May 31, 1994
    Assignee: North American Philips Corporation
    Inventor: Stephen Macocs
  • Patent number: 5313288
    Abstract: A recording medium has first and second transparent electrodes, a photoconductive layer member and a photomodulation member. The recordingmedium also has a first lamination member having a first substrate on which the first transparent electrode and the photoconductive layer member are laminated in order, a second lamination member having a second transparent substrate on which the second transparent electrode and the photomodulation layer member are laminated in order and coupling members for unifying the first and second lamination members together with a gap of specific width in such a manner that the photoconductive and photomodulation layer members face each other.
    Type: Grant
    Filed: March 4, 1992
    Date of Patent: May 17, 1994
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Tsutou Asakura, Masato Furuya, Yoshihisa Koyama, Yuji Uchiyama
  • Patent number: 5301017
    Abstract: A projection-type display apparatus having a lamp which emits a high intensity white light, two dichroic mirrors which filter out the three primary color beams from the white light and three liquid crystal panels which, respectively, modulate the color beams according to the three color image signals. Characteristics of the lamp and the dichroic mirrors are set so that the reproduction chromaticity range includes transmission chromaticity ranges of both the NTSC and HDTV systems. The image signals are supplied to two types of linear matrix circuit which are, respectively, suited for the NTSC and HDTV systems in order to correct color reproduction errors. The output of the linear matrix circuits are selected according to the system of the received television signal. In addition, a display white color temperature is set in the corrected image signals according to the system. Thus, the image signals are supplied to a display device such that the colors of the image can be accurately reproduced.
    Type: Grant
    Filed: August 11, 1993
    Date of Patent: April 5, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Seiji Murakami
  • Patent number: H1320
    Abstract: A method for producing a natural color display on a display panel, wherein means for reformatting video signal images for a grey-scale matrix liquid crystal or ferroelectric liquid crystal panel such that frames of image are presented sequentially in time, each frame containing the information of a particular color, and then illuminating said image with the appropriate primary color light. Such images are presented to the viewer at a rate above the color fusion frequency of the eye and thus appear as a full color image.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: June 7, 1994
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Robert V. Kieronski