Plural Light Path Projectors Patents (Class 349/8)
  • Patent number: 5934778
    Abstract: An optical system for a liquid crystal projector in which the deterioration of the contrast of a projection screen is prevented. The optical system, comprising: a light source 1 for emitting a white light, an optical divider 4, 5 for dividing said white light into red, green and blue lights, a liquid crystal display panel 17, 18, 19 for modulating each of said red, green and blue light, a polarizer 14, 15, 16 for polarizing each of said modulated red, green and blue light, an optical synthesis element 21 for synthesizing each of said polarized red, green and blue light, and a green-light removing element 23, 24, 25 for removing green light disposed between said liquid crystal display panel for said blue light and said color synthesis element. The green-light removing element 23, 24, 25 removes is provided between the blue-light modulating LCD panel 19 and the color synthesis element 21. Therefore the deterioration of the contrast of the blue-light modulating LCD panel 19 can be prevented.
    Type: Grant
    Filed: July 29, 1998
    Date of Patent: August 10, 1999
    Assignee: NEC Corporation
    Inventor: Yukinori Shioya
  • Patent number: 5933205
    Abstract: A novel structure of an active electro-optical device is disclosed. The device is provided with complementary thin film insulated gate field effect transistors (TFTs) therein which comprise a P-TFT and an N-TFT. P-TFT and N-TFT are connected to a common signal line by the gate electrodes thereof, while the source (or drain) electrodes thereof are connected to a common signal line as well as to one of the picture element electrodes.In case of driving the active electro-optical device, a gradation display can be carried out in a driving method having a display timing determined in relation to a time F for writing one screen and a time (t) for writing in one picture element, by applying a reference signal in a cycle of the time (t), to the signal line used for a certain picture element driving selection, and by applying the select signal to the other signal line at a certain timing within the time (t), and whereby setting the value of the voltage to be applied to a liquid crystal.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: August 3, 1999
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Akira Mase, Masaaki Hiroki
  • Patent number: 5926240
    Abstract: The liquid crystal display apparatus has a pair of substrates. One of the paired substrates includes active matrix elements and reflective pixel electrodes. The other substrate includes a transparent electrode. A liquid crystal layer is provided between the paired substrates, with a single-layer dielectric film disposed between the reflective pixel electrodes and the liquid crystal layer.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: July 20, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Shoichi Hirota, Hideo Sato, Iwao Takemoto, Toshio Saito
  • Patent number: 5918961
    Abstract: A color projection display device separates light into the colors of red, green and blue. Each of the color components is modulated, superimposed with the other components again and projected. The device provides color picture images with few irregularities in illumination intensity. Polarizing beam splitters used for modulation of the colors are constructed from base materials having a minimum absolute photoelasticity constant value at different wavelengths. Thus, the absolute photoelasticity constant value of the base material for a particular wavelength of light that is separated by the polarizing beam splitter can be made small and double refractions, resulting from stress, are unlikely to occur in any of the components. As a result, a disturbance in the polarization and separation performance is unlikely to occur, and irregularities in the illumination intensity can be reduced.
    Type: Grant
    Filed: May 7, 1997
    Date of Patent: July 6, 1999
    Assignee: Nikon Corporation
    Inventor: Motoi Ueda
  • Patent number: 5917561
    Abstract: The image processing apparatus includes a lamp, fly eye lenses, an R reflective dichroic mirror, an R liquid-crystal light valve, a G reflective dichroic mirror, a G liquid-crystal light valve, a B dichroic light valve, a dichroic prism, and a projection lens for projecting a synthesized color image. In addition, a color-impurity correcting filter is provided typically between the R reflective dichroic mirror and the mirror to form an inclination angle of 10 degrees with a normal axis Y perpendicular to the incident-light axis X in the clockwise rotational direction around a normal axis Z. As a result, the color purity of the image displayed on the screen is improved and the luminance distribution of the displayed image can also be made uniform as well.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: June 29, 1999
    Assignee: Sony Corporation
    Inventor: Masato Hatanaka
  • Patent number: 5917560
    Abstract: A liquid crystal projector and color beamsplitter that comprises a single X-cube beamsplitter that transmits both incident and exit light beams. One half of the beamsplitter divides incident white light into three primary colors, and the other half of the beamsplitter combines the primary colors to produce white light that is used for projection. More specifically, the projector comprises a light source for projecting white light, and the color beamsplitter is disposed to receive the white light. The beamsplitter comprises four (right angle) prisms that each comprise a base and two sides, and that are disposed such that the sides of the prisms are adjacent each other. The incident white light is separated by the prisms and coupled along three separate light paths corresponding to red, green and blue light paths. Apparatus such as a plurality of mirrors, or an optical link, for example, are provided for coupling the red, green and blue light back toward the beamsplitter.
    Type: Grant
    Filed: November 28, 1995
    Date of Patent: June 29, 1999
    Assignee: Raytheon Company
    Inventor: Margarete Neumann
  • Patent number: 5903388
    Abstract: This invention relates to electromagnetic wave beam paths, formation of the beam, illumination of programmable electromagnetic wave field vector orientation rotating devices ("PEMFVORD") with an electromagnetic beam, and the technique of projection of the modulated beam. This invention also relates to a unique light path and method of forming the light into a rectangular beam to be used for optical projection systems and, more particularly, in a color and/or black and white liquid crystal device (LCD) projectors that produce high resolution, high brightness and/or three-dimensional images. This invention further relates to a device capable of receiving and displaying two-dimensional and three-dimensional images.
    Type: Grant
    Filed: November 4, 1996
    Date of Patent: May 11, 1999
    Inventor: Steven R. Sedlmayr
  • Patent number: 5897190
    Abstract: This invention provide an image display apparatus having an illumination optical system for effectively illuminating a plurality of areas on a single common plane uniformly by shortening optical paths of the optical system and a new projection optical system capable of reducing the overall size of the optical system and a production cost thereof. The illumination optical system has an ellipse mirror for collecting light beams generated from a light source, a first lens group for suppressing divergence of the light beams reflected from a light collecting area of the ellipse mirror, a plural color filters for separating the light beams into three color light beams and altering a path of each of the three color light beams, and a second lens group for illuminating objects disposed on the single common plane by focusing the separated three color light beams thereon.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: April 27, 1999
    Assignee: Victor Company of Japan, Ltd.
    Inventor: Ryusaku Takahashi
  • Patent number: 5896226
    Abstract: Optical device for viewing a virtual three dimensional image superimposed on a real object and characterized in that it includes means for forming a three dimensional virtual image and two semi-transparent mirrors arranged between the observer and the real object at a given angle of inclination to reflect the computer-generated virtual image of the real object.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: April 20, 1999
    Assignee: Centre National de la Recherche Scientifique (CNRS)
    Inventors: Bernard Peuchot, Alain Tanguy, Michel Eudes
  • Patent number: 5889567
    Abstract: Binary optics are used in an illumination system for a color projection display. In one embodiment a broad spectrum light source illuminates a multilevel optical phase element which disperses the broad spectrum light from the light source by diffraction. A display having a number of pixel elements, each capable of transmitting a predetermined spectral region, is positioned within the near field region of the multilevel optical phase element so as to receive the light dispersed by the multilevel phase element.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: March 30, 1999
    Assignees: Massachusetts Institute of Technology, Kopin Corporation
    Inventors: Gary J. Swanson, Ronald P. Gale
  • Patent number: 5886754
    Abstract: A projection-type display device using twisted nematic liquid crystal light valves having multi-twist and/or multi-polarization angles. The photoelectric transfer characteristics of three light valves are optimized for reflecting red, green and blue light with high efficiency and similar reflectivity by selecting proper twisted angle and polarization angle for each corresponding liquid crystal light valve. The twisted angle or polarization biasing angle of each light valve may be different.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: March 23, 1999
    Assignee: Industrial Technology Research Institute
    Inventor: Chen-Lung Kuo
  • Patent number: 5877824
    Abstract: This system for illuminating a liquid-crystal screen comprises a light source which emits an unpolarized light beam (F). A polarizing splitter device (PBS) receives this unpolarized light beam and retransmits, onto the liquid-crystal screen, a first and a second beam (F1, F2) which are polarized in the same polarization direction. The axes of the two beams make a defined angle (2.beta.) between them. A matrix of microlenses is provided with one microlens (.mu.L) for at least two adjacent picture elements (EL1, EL2) in the liquid-crystal screen. Each microlens directs that part of the first beam which it receives onto one (EL1) of the two picture elements and that part of the second beam which it receives onto the other picture element (EL2).
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: March 2, 1999
    Assignee: Thomson multimedia, S.A
    Inventor: Khaled Sarayeddine
  • Patent number: 5875008
    Abstract: In an optical system phase device such as .lambda./2 plate or a .lambda./4 plate is used to convert S polarization to P polarization and vice versa. In the projection display, a white light emitted from a light source is separated by a color separation optical system, including dichroic mirrors or a dichroic prism, into three primary colors which are modulated by optical modulation elements. Then, the modulated lights are synthesized by a color synthesis optical system and projected by a projection element onto a screen. When appropriate plates are inserted appropriately in the optical system of the projection display, the conversion between S and P polarization occurs and an optical bandwidth becomes narrow, and color purity can be improved. A thick transparent plate is preferably adhered to the optical modulation element. A light absorption film is applied to an ineffective plane of the transparent plate.
    Type: Grant
    Filed: February 5, 1997
    Date of Patent: February 23, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Takahara, Hideki Ohmae, Yoshito Miyatake, Mitsuhiro Wada
  • Patent number: 5853240
    Abstract: A small and light liquid-crystal projector, a projector making a combination with a head-mounted display and a small-and-light projector device for projecting an image or three-dimensional image from the HMD onto a common screen: the HMD has, in its casing, an optical device for enlarging an image of a liquid-crystal panel illuminated by a back light, which device comprising a reflection type refracting element with a half-mirror coat and a cholesteric liquid crystal element acting as circularly-polarized-light selecting semitransparent mirror; a base unit with which the HMD is connected to form a projector device has, in its housing, an optical correcting portion, a projector back-light, a light-source changing portion and a mechanism for inserting the optical correcting portion for correcting the curvature of a projectable image; when assembling the HMD with the base unit, the light-source changing portion acts so as to illuminate the liquid crystal panel with intensive back-light though a parabolic mirror
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: December 29, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Seiichi Tanaka, Atsushi Yamanaka
  • Patent number: 5847792
    Abstract: An active matrix type liquid crystal display panel comprises a first substrate having a plurality of active devices, a plurality of scanning bus lines, a plurality of data bus lines, and a plurality of pixel electrodes, a second substrate having opposed electrodes on its surface opposing to the first substrate, a first shielding film formed on top of the active devices and between the pixel electrodes on the first substrate, a second shielding film formed in at least areas opposing to semiconductor regions of the active devices on the second substrate, and liquid crystals sealed between the first substrate and the second substrate.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: December 8, 1998
    Assignee: Fujitsu Limited
    Inventors: Tetsuya Kobayashi, Toshihiro Suzuki, Takeshi Gotoh, Hisashi Yamaguchi, Kazutaka Hanaoka, Yasutoshi Tasaka, Seiji Tanuma, Makoto Ohashi, Takashi Sasabayashi, Yohei Nakanishi
  • Patent number: 5847784
    Abstract: A self adjusting tiled image display system and method is provided. In operation, an image source having an array of tiled image displays projects a test image pattern. A positioning device is attached to a corresponding one of the image displays for positioning that image display. A sensor senses the test image pattern projected by the image displays and generates a sensor signal indicative of the sensed test image pattern. A processor compares the sensor signal to a proper alignment signal indicative of the image displays being properly aligned to generate a positioning signal. The processor applies the positioning signal to the positioning devices to position the image displays as a function of the positioning signal until the image displays are in the proper alignment.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: December 8, 1998
    Assignee: Hughes Electronics Corporation
    Inventors: Ronald M. Finnila, Donald C. Mead
  • Patent number: 5844637
    Abstract: A semiconductor device can be prevented from mal-functioning by interrupting reflected beam. Polarizing plates (1), (3) are disposed at beam entrance and exit sides, respectively of a transmission liquid-crystal display device (2) as polarizers. Beam from the polarizing plate (3) has the change of light and shade presented in accordance with a video signal. An optical isolator using a quarter-wave plate (4) is disposed at the beam exit side of the polarizing plate (3). A glass panel (5) such as an optical filter is disposed at the beam exit side of the quarter-wave plate (4), whereby beam from the polarizing plate (3) is converted into linearly-polarized beam having an arbitrary plane of polarization. When this linearly-polarized beam is introduced into the optical isolator using the quarter-wave plate (4), inputted linearly-polarized beam is converted into circularly-polarized beam by action of the quarter-wave plate (4). The thus converted circularly-polarized beam is irradiated on the glass panel (5).
    Type: Grant
    Filed: March 3, 1997
    Date of Patent: December 1, 1998
    Assignee: Sony Corporation
    Inventor: Masao Katsumata
  • Patent number: 5838415
    Abstract: A liquid crystal panel includes a liquid crystal layer sandwiched by first and second substrates, wherein a transparent film is adhered on at least one of the first and second substrates by an intervening adhesive layer, such that the adhesive layer fills defects formed on a surface of the substrate with a material having a refractive index close to the refractive index of the substrate. Further, a liquid crystal projector having an improved cooling efficiency is disclosed.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: November 17, 1998
    Assignee: Fujitsu Limited
    Inventors: Keiji Hayashi, Tetsuya Hamada, Takeshi Gotoh
  • Patent number: 5822025
    Abstract: A high performance single light valve color projection system that enables sequential display of color, and an addressing process for this system. Several rotating glass plates are sequentially inserted between the light valve and the objective. These glass plates create a spatial offset of the image of light valve pixels three times per frame on the projection screen. The sets of plates are rotated by a motor with an axis parallel to the optical axis of the motor, and intersect the image beam at each image frame.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: October 13, 1998
    Assignee: Thomason multimedia S.A.
    Inventors: Thierry Borel, Khaled Sarayeddine
  • Patent number: 5812223
    Abstract: An LCD projector which has a white light source for emitting a randomly polarized luminous flux, and a plurality of LCD panels for modulating luminous fluxes that are transmitted through the LCD panels. The LCD projector also includes four reflecting devices. The first reflecting device reflects a first portion of the luminous flux having a first polarization characteristic and a wavelength which is within a first predetermined range of wavelengths, to the first LCD panel. The second reflecting device reflects a second portion of the luminous flux that is not reflected to the first LCD panel, to the second LCD panel. The second portion of the luminous flux has the first polarization characteristic and a wavelength which is within a second predetermined range of wavelengths. The third reflecting device reflects a third portion of the luminous flux that is not reflected to the second LCD panel, to the third LCD panel.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: September 22, 1998
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventor: Masato Noguchi
  • Patent number: 5805244
    Abstract: A liquid crystal projector using monochromatic liquid crystal displays (LCDs). The liquid crystal projector includes a filter for filtering light emitted from a light source and for outputting a white light. A condenser lens group then condenses the white light, and, thereafter, the condensed white light is separated into the three primary colors of light by (color filters and applied to an LCD part comprising monochromatic LCDs. The LCD part outputs video images corresponding to the three primary colors of light separated according to an applied video signal. A reflective part their combines the outputted video images and outputs the combined video image to a projector lens. Finally, the projector lens projects the combined video image onto a screen.
    Type: Grant
    Filed: December 11, 1996
    Date of Patent: September 8, 1998
    Assignee: Samsung Aerospace Industries, Ltd.
    Inventor: Inh-Seok Suh
  • Patent number: 5801814
    Abstract: A split image exposure method capable of realizing high-resolution and high-quality exposure of an image by suppressing discontinuity of density and color in junctions between split images when the original image divided into a plurality of subdivisions is exposed using a planar element. A LCD panel can be positioned at four different locations in a horizontal plane, and it receives light from a light source in respective locations and can print a transmission image onto a color printing paper through a projection lens system by exposure. A reference mark is captured based on a difference in the amounts of light received by light receiving portions of the sensor, whereby the positioning of the LCD panel can be completed. The occupancy ratio of image data representing each split image is varied in double-exposed or fourfold-exposure areas, and the density of each pixel of the liquid crystal panel is controlled in accordance with this occupancy ratio.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: September 1, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Nobuo Matsumoto
  • Patent number: 5801794
    Abstract: The invention relates to a color display device comprising a chromatic dispersive grating and an active matrix possibly of liquid crystal type. This device moreover comprises a matrix of spherical microlenses, the shape of the cross section of the microlenses being such that it makes it possible to compensate for the spreading of the R G B colored beams by virtue of the use of a dispersive grating, and hence to make best use of the circular aperture of projection objectives.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: September 1, 1998
    Assignee: Thomson-CSF
    Inventors: Jean-Claude Lehureau, Brigitte Loiseaux, Cecile Joubert
  • Patent number: 5786874
    Abstract: On the incident sides of the blue light modulating liquid crystal panel and the green light modulating liquid crystal panel, condenser lenses whose outer diameter is equal to or more than that of the two liquid crystal panels are disposed respectively. No condenser lens is disposed on the incident side of the red light modulating liquid crystal panel. The focal length f of the two condenser lenses is preferably set to be a value of(L.sub.1 .multidot.L.sub.2)/(L.sub.1 +L.sub.2),where L.sub.1 is the distance between each condenser lens and the light source, and L.sub.2 is the distance between each condenser lens and the projection lens. The direct light from the discharge lamp and incident upon the condenser lenses is all incident upon the projection lens. Alternatively, a condenser lens may be disposed on the incident side of the red light modulating liquid crystal, but having a focal length which is longer than the other condenser lenses, preferably equal to L.sub.1.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: July 28, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Naoki Kawamoto, Masanori Kojima
  • Patent number: 5781252
    Abstract: The present invention relates to a light valve projector in which a pair of high resolution active matrix transmission displays are used with a light source, coupling optics and a projection lens to provide a compact video or data presentation system. A preferred embodiment of the system comprises a two light valve system and a lamp within a compact housing where light from the lamp is directed through two active matrix displays using a pair of diffractive optical elements.
    Type: Grant
    Filed: April 2, 1996
    Date of Patent: July 14, 1998
    Assignee: Kopin Corporation
    Inventor: Ronald P. Gale
  • Patent number: 5767924
    Abstract: A display unit includes an optical modulation element for subjecting an incident light beam to optical modulation, and a coolant disposed in contact with an output side of the optical modulation element, wherein a focal distance of an output light beam of the optical modulation element is set to a predetermined distance in accordance with a length of the output light beam of the optical modulation element, which passes through the coolant.
    Type: Grant
    Filed: June 7, 1996
    Date of Patent: June 16, 1998
    Assignee: Semiconductor Energy Laboratory Co.,
    Inventors: Masaaki Hiroki, Jun Koyama, Toshimitsu Konuma, Shunpei Yamazaki
  • Patent number: 5764319
    Abstract: The invention provides a small-sized high-resolution transmissive display device which can be employed in a projector of the color-filterless type. The transmissive display device includes a pair of transparent substrates connected to each other via a predetermined space. The transparent substrates are provided with electrodes forming pixels arranged in a matrix form. The above-described space is filled with an electrooptical material so that the transmissivity of an incident light ray is modulated by the electrooptical material for each pixel and thus converted into an emerging light ray. The transparent substrate on the incident side is further provided with micro lenses and micro prisms. The incident light ray includes three primary color components which have been separated so that they enters the transparent substrate at angles different from each other.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: June 9, 1998
    Assignee: Sony Corporation
    Inventor: Shizuo Nishihara
  • Patent number: 5754260
    Abstract: A light source optical system for projection 1, dichroic mirrors 21, 22 disposed to have a predetermined included angle .beta., a reflection type liquid crystal optical element blocks 31-33 each including a closely contacted converging lens and having a reflection surface and a projection optical system 4 are provided, wherein the normal line of a dichroic mirror surface and the optical axis of incident light form an included angle .alpha.; the normal line of the reflection surface and the optical axis of incident light form an included angle .gamma.; light emitted from a light source is color-separated so as to become color lights; the color lights are rendered to be parallel light beams, and are modulated and reflected by means of the reflection type liquid crystal optical elements; the reflected light beams are color-synthesized; and the color-synthesized light is projected through a projection lens.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: May 19, 1998
    Assignee: AG Technology Co., Ltd.
    Inventors: Yoshiharu Ooi, Tsuneo Wakabayashi, Shigeyuki Serizawa, Yoshiyuki Sonda, Masaya Kunigita, Yoshinori Hirai
  • Patent number: 5748379
    Abstract: The invented optical engines are characterized as including generally parallel planar glass plate-mounted or coated dichroic and turning mirror and light valve elements. An important topological feature of the invented optical engines is the fact that like optical elements are positioned and oriented to be coplanar, i.e. the light-splitting dichroic mirror elements are coplanar with one another, the split beam-turning mirror elements are coplanar and the light valves are coplanar. This important feature of the invention renders compact optical engines that are simply and inexpensively manufactured and maintained because the critical optical elements are in part self-aligning when like optical elements are placed in an aligning mounting structure or more preferably on a common substrate that renders them self-positioning and self-aligning relative to one another.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: May 5, 1998
    Assignee: Delta America Ltd.
    Inventors: Kenneth E. Salsman, Amjad I. Malik, Gary B. Kingsley
  • Patent number: 5726719
    Abstract: The projection-type color display device of the invention includes: a white light source; a splitting means for splitting white light emitted from the white light source into a first, a second, and a third beam having respectively different wavelength regions; a modulation means for modulating the first, the second and the third beams; an irradiation means for irradiating the first, the second and the third beams onto a principal surface of the modulation means at respectively different angles; and a projection means for projecting the first, the second and the third beams modulated by the modulation means. In the projection-type color display device, the first beam includes a color beam having a weakest intensity among the beams in three primary colors contained in the white light; and a direction of the first beam incident onto the principal surface of the modulation means is closer to a normal of the principal surface of the modulation means as compared with the second and the third beams.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: March 10, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Naoyuki Tanaka, Hiroshi Hamada, Hiroshi Nakanishi, Hideki Ohshima
  • Patent number: 5696564
    Abstract: A video projector including a light source and a light valve for receiving light emitted from the light source. A first filter is disposed between the light source and the light valve. The first filter removes light having a bandwidth ranging from ultraviolet to a wavelength within the visible spectrum of light and infrared light from the light emitted from the light source. A second filter is disposed between the first filter and the light valve. The second filter removes light having a bandwidth ranging from ultraviolet to a wavelength within the visible spectrum of light.
    Type: Grant
    Filed: February 28, 1996
    Date of Patent: December 9, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Atsushi Hatakeyama
  • Patent number: 5691785
    Abstract: The present invention provides a color projector utilizing three liquid crystal display elements. The natural light is separated into illuminating rays of red, green and blue colors by a dichroic mirror, each of these illuminating rays being used to illuminate the corresponding one of the liquid crystal display elements. Each of the liquid crystal display elements is controlled by a desired image signal with respect to its transmittance at each pixel. After passed through the liquid crystal display elements, three kinds of colored illuminating rays are again synthesized by the other dichroic mirror to form a light beam which in turn is enlarged and projected by a projecting lens on a screen. By providing light source means including means for converting the natural light into the linearly polarized beam, the illuminating rays may have their polarizing angles coincide with each other without any loss of light.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: November 25, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masahiro Usui, Hiroshi Kida, Shinsuke Shikama, Mitsushige Kondo
  • Patent number: 5689321
    Abstract: A display apparatus comprising a reflective type panel displaying images by reflecting the light from at least one light source, wherein each of a plurality of pixel electrodes of the reflective type panel is composed of a reflective electrode. Each inclination angle of the pixel electrodes with respect to the panel surface is arranged to be different from others.
    Type: Grant
    Filed: April 9, 1996
    Date of Patent: November 18, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tetsunobu Kochi
  • Patent number: 5682212
    Abstract: The invention relates to optical elements having image-forming, color- and polarization-selective reflection and containing cholesteric liquid crystals, and to the preparation and use of these elements. In the wavelength- and polarization-selective elements which form an optical image, at least one cholesteric liquid crystal is enclosed in the cavity of constant thickness between two light-transmitting substrates having curved surfaces in such a way that the helix axis of the liquid crystal is aligned perpendicular to the curved surface of the light-transmitting substrates. The elements are suitable for use as beam splitters or recombiners in projection displays.
    Type: Grant
    Filed: August 22, 1994
    Date of Patent: October 28, 1997
    Assignee: Consortium fur elektrochemische Industrie GmbH
    Inventors: Robert Maurer, Stefan Beiergroesslein, Franz-Heinrich Kreuzer
  • Patent number: 5623349
    Abstract: In a color liquid crystal projection display in which three differently-colored illuminating beams (R,G,B) are incident from mutually different directions on an LC panel (20) having an array of display elements (40) with a microlens array (21) at the input side of the panel comprising microlens elements (42) overlying groups of display elements that direct light from the beams through respective sets of display elements, and a projection lens (30) projects the output beams from the panel onto a screen (31), the beam geometries are selected such that at a position spaced from the output side of the panel the three output beams pass respectively through substantially separate areas and filter means (50) are disposed at that position to remove unwanted color stray light at each area thus improving color purity.
    Type: Grant
    Filed: June 27, 1995
    Date of Patent: April 22, 1997
    Assignee: U.S. Philips Corporation
    Inventor: John A. Clarke
  • Patent number: 5621551
    Abstract: An LCLV projection system (10) includes color separation dichroic mirrors (50, 52) positioned between a group of reflective liquid crystal light valves (38, 40, 42) and a polarizer analyzer (26) which enables a single projection lens (34) to project all colors via a light beam of single linear polarization with a high degree of contrast, efficiency and color separation. The polarizer analyzer (26) directs a light beam with a single polarization state to a pair of dichroic filters (50, 52) which separate the beam into three different colors that are sent to three different reflective liquid crystal light valves (38, 40, 42). The light valves reflect the respective colored light beams with change in polarization state back to the dichroic mirrors (50, 52) which combine the three colors into a single combined multi-color beam that is fed through the polarizer analyzer (26) to a single system projection lens (34).
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: April 15, 1997
    Assignee: Hughes-JVC Technology Corporation
    Inventors: Alan R. Henderson, Ralph Gagnon
  • Patent number: 5363132
    Abstract: An ink jet apparatus for discharging a plurality of kinds of ink to a recording medium to thereby effect color recording has a plurality of recording head for discharging the inks to thereby effect recording, a carriage carrying the plurality of recording head thereon to be scanned along the recording medium, and forwardly and backwardly moving members for moving the plurality of recording heads carried on the carriage forwardly and backwardly independently of one another.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: November 8, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventor: Masatoshi Ikkatai