Unitary Sheet Comprising Plural Reflecting Areas Patents (Class 359/459)
  • Patent number: 6570706
    Abstract: A two element low energy source front projection screen for pictorially displaying upon a front face of the screen an image projected onto the front face from a projector comprised of a metallic support sheet having a front reflective surface and a sheet of lenticular lenses which overlays the front reflective surface of the support sheet. The lenticular lenses provide a focal point of reflective light on their surface in a narrow bright serpentine line separated from each other by dark regions. This optical arrangement is perceived by the eye as the brightness of the bright lines rather than the average brightness of the whole region.
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: May 27, 2003
    Inventors: Nickey J. Atchison, Brad Ferrell
  • Patent number: 6552848
    Abstract: A rear projection type screen is provided with a Fresnel lens and a lenticular lens, for use with a light valve having pixels. The rear projection type screen has such lens pitches that the secondary moiré pitch PMM indicated by the following equation is 3 mm or less, taking the lens pitch of the Fresnel lens as PF (mm), the lens pitch of the lenticular lens as PL (mm), and the pitch of the pixels in the light valve as PS (mm).
    Type: Grant
    Filed: September 13, 2001
    Date of Patent: April 22, 2003
    Assignee: Kuraray Co., Ltd.
    Inventor: Hideki Kobayashi
  • Patent number: 6538814
    Abstract: An active screen reflects a high contrast projected image. The screen has (1) an active layer having visible optical properties changed by an electric field provided by electrodes and (2) a photosensitive layer. The photosensitive layer is such that the electric field across a localized area of the active layer depends on the illumination incident on the photoconductor in that area. The local reflectance of the projection screen thus depends on the intensity of light incident upon it. In one embodiment, the reflectance of the screen increases with increasing light intensity to produce a high contrast reflected image.
    Type: Grant
    Filed: March 22, 2001
    Date of Patent: March 25, 2003
    Assignee: Hewlett-Packard Company
    Inventors: Andrew Arthur Hunter, John Christopher Rudin
  • Patent number: 6530664
    Abstract: A front projection screen and associated system and method are disclosed that utilize a back structured layer and a front diffusing layer to provide improved viewable image quality. The structured layer is formed with a plurality of grooves and can operate to direct light into a defined audience view region. The diffusing layer is coupled to the structured layer and is formed from a matte polyester film to provide dry erase capability on a front surface of the diffusing layer. For example, the matte polyester film can be TEKRA Marnot XL matte Melinex polyester film. Further, the structured layer can be formed as an acrylate linear prismatic structure having a gloss white coating. The acrylate linear prismatic structure and the matte polyester film can be coupled, for example, by lamination or can be coupled by being extruded as a unitary construction.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: March 11, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Dennis F. Vanderwerf, Patricia M. Hughes, Ernesto M. Rodriguez, Jr.
  • Patent number: 6452653
    Abstract: A reflector comprises a substrate provided with a plurality of projecting and depressed structures which are groups of columnar portions each serving as a basic unit and composed of a plurality of minute columnar portions, which are separate from each other or at least partially connected to each other, and with a light reflecting thin film provided over the projecting and depressed structures. This allows incident light to be scattered and reflected in a forward direction or the like, not in the regular reflection direction, and provides a reflector having a superior contrast property and a superior paper-white property, a fabrication method therefor, and a reflective display device comprising the reflector. The reflective display device has a liquid crystal layer provided between a pair of substrates. One of the pair of substrates is provided with projecting and depressed portions covered with a metal film and with a support portion for supporting the counter substrate, which are molded integrally.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: September 17, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuhiko Yamanaka, Naohide Wakita, Takeshi Karasawa, Mariko Kawaguri, Seiji Nishiyama
  • Patent number: 6414727
    Abstract: A laser projection video system and a holographic screen. The system includes a pulsed laser video image system with a holographic screen to receive the full color video image, which screen has a holographic layer (layer 1) to reflect back the full color video image to the viewer and to transmit through the screen the ambient light to provide high video picture contrast.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: July 2, 2002
    Assignee: Corporation for Laser Optics Research
    Inventor: Stephen A. Benton
  • Patent number: 6404548
    Abstract: A reflection type screen having a high SG value, a wide view angle and an excellent color reproducibility of bright parts of projected image is provided. The reflection type screen comprises a substrate having a light reflecting property such as a white plastic film and a light diffusion layer 2 formed on the substrate, which contains a light diffusion agent and a pearl pigment dispersed in a binder resin. The pearl pigment is mica covered with titanium dioxide and has an optical characteristic reflecting blue component of light projected by a projector and transmitting light of a color complementary to blue. When PC images having many white parts or the like are projected on the screen, the bright part of the images does not become yellowish and projected images with high whiteness can be obtained. The content of pearl pigment is preferably 5-100 parts by weight based on 100 parts by weight of the binder resin and 10-150 parts by weight based on 100 parts by weight of the light diffusion agent.
    Type: Grant
    Filed: July 6, 2000
    Date of Patent: June 11, 2002
    Assignees: Kimoto Co., Ltd., Izumi-Cosmo Co., Ltd.
    Inventors: Koji Tatsuki, Hideo Takamoto, Tetsujiro Omura
  • Patent number: 6359732
    Abstract: Provided is a plastic sheet for rear projection screens, which has a two or more multi-layered structure and which can be readily warped without being unfavorably swollen or waved. The plastic sheet is constructed to have a two or more multi-layered structure, in which the coefficient of linear expansion (at 20° C.) of one layer is higher by at least 1.0×10−6 mm/(mm·°C.) than that of any other layer. In one embodiment of the plastic sheet, the layer of which the coefficient of linear expansion is higher than that of any other layer contains a fine particulate rubber material having a diameter of from 0.1 to 100 &mgr;m to such a degree that the rubber material content thereof is higher by at least 0.5% by weight than that of any other layer.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: March 19, 2002
    Assignee: Kuraray Co., Ltd.
    Inventor: Osamu Yoshimura
  • Patent number: 6335828
    Abstract: A micro-lens array sheet having a wide field angle, a field angle control, a high light efficiency, a high brightness and a high contrast, which is provided with a layer of micro-lenses each shaped to be a centro-symmetry convex or concave micro-lens. A layer of either a light diffusion sheet or a sheet filled with light diffusive agent is attached on a light transmitting side of the micro-lens array sheet. The micro-lenses are aligned in a diamond grid array or an array including a combination of diamond-shape and hexagonal-shape micro-lens blocks.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: January 1, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Hashimoto, Tsutomu Sakamoto
  • Patent number: 6226127
    Abstract: A substrate is arranged to provide at least one optically variable image the substrate has a front surface formed with a plurality of groups of elemental areas, the different said groups of elemental areas corresponding to respective pixels of the image. The different elemental areas of each group are formed with respective sets of grooves or ridges, where the grooves and ridges of different elemental areas of each group are disposed at different orientations in the different elemental areas, such that each elemental area directs light to a viewer from a respective angle of view. For any given angle of view, the image seen by the viewer is made up of light reflected or refracted without interference.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: May 1, 2001
    Assignee: Fryco Limited
    Inventors: Paul Dunn, Andrew Rowe
  • Patent number: 6144491
    Abstract: A reflection-type projection screen includes a substrate, a light-reflecting layer made from a transparent resin in which flakes of a light-reflective material are dispersed, and a transparent light-diffusing layer made from a transparent resin in which fine crystalline particles of calcite and an achromatic dye or pigment are dispersed. The surface of the light-diffusing layer functions as a projection-light-receiving, image-observation surface which receives the incident projection light and on which an image to be observed is formed. A lubricant can be incorporated into the light-diffusing layer. The calcite particles slightly absorb light and have moderate light-diffusing properties. As a result, the transmittance of the light-diffusing layer is increased. The light-reflecting layer has a high reflectance. Due to the synergistic effect of the properties of the two layers, the projection screen has a high reflection luminance (high gain).
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: November 7, 2000
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Toshiyuki Orikasa, Eiichiro Yokochi, Kazuko Eto
  • Patent number: 5914825
    Abstract: In a reflector for a display to be placed on the back surface of a reflection-type display, the section of the reflector is made serrated so that the shape of the serration will be an isosceles or scalene triangle, and, at the same time, the serrated reflecting surface is finely roughened. The roughness of the finely roughened reflecting surface is so controlled that the center line average height Ra will be 1 micrometer or more and 6 micrometers or less and that the ten-point average height Rz will be 1 micrometer or more and 10 micrometers or less. By this, images displayed on a display into which the reflector is incorporated can be observed without being obstructed by surface-reflected light, and also brightly observed in a wide angle.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: June 22, 1999
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Toshikazu Nishio, Hisanori Ishida
  • Patent number: 5837346
    Abstract: Various forms of light-diffusing screen are disclosed comprising plastics sheets having surface texturing of some kind, adding to or modifying the diffusing effect. The plastics sheets may have bulk diffusing characteristics in addition to the surface texturing. The surface texturing may be produced by, for example, embossing or by molding the plastics against a textured surface such as a "brushed" surface or a ribbed or grooved surface imparting asymmetrical diffusion characteristics to the screen.
    Type: Grant
    Filed: November 15, 1996
    Date of Patent: November 17, 1998
    Assignees: Nashua Corporation, Nashua Photo Limited
    Inventors: William Langille, Robin Clabburn
  • Patent number: 5835269
    Abstract: A video display apparatus has a dot matrix of LEDs mounted on an LED matrix board, and a unitary reflecting member made of metal such as aluminum or the like mounted on the LED matrix board. The reflecting member has slanted reflecting surfaces disposed vertically one on each side of each of the LEDs for reflecting light emitted from the LEDs with narrow vertical directivity. The video display apparatus can provide a wide angle of view in the horizontal direction, and a narrow angle of view in the vertical direction for preventing light from being scattered in the vertical direction to maintain a desired level of luminosity.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: November 10, 1998
    Assignee: Sony Corporation
    Inventor: Takehisa Natori
  • Patent number: 5815313
    Abstract: The present invention makes it possible to improve color shift, shading and view angles, to prevent external light absorption and reflection, to enhance external light contrast, to eliminate reflection of external images that appear on a light transmission screen's face plate, and to provide distinct pictures free of the adverse effects of dust. The light transmission screen disclosed by the present invention comprises a Fresnel lens sheet, a transparent lenticular lens sheet arranged on the Fresnel lens sheet's radiant light side and a front diffusion panel formed of a thin diffusion layer and a transparent layer and arranged on the lenticular lens sheet's light radiant side.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: September 29, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Katsuaki Mitani, Hirokazu Sakaguchi, Satoshi Aoki
  • Patent number: 5717522
    Abstract: In an apparatus for displaying a three-dimensional image, an image display and a polarizing filter having an axis of easy transmission in a predetermined direction or an optically-active film having an optically-active portion at a predetermined position are combined together in a predetermined positional relationship, thereby easily displaying an image on the image display when a flat original image is prepared for forming the three-dimensional image and simplifying the structure of the apparatus with a reduced manufacturing cost.
    Type: Grant
    Filed: July 24, 1995
    Date of Patent: February 10, 1998
    Assignee: Fuji Photo Optical Co., Ltd.
    Inventors: Tomohiko Hattori, Takayuki Saito
  • Patent number: 5696625
    Abstract: A flat screen receives light from a light projector at a projector location, and reflects the light to a spectator area. The screen has a center, spaced apart upper and lower edges and a pair of spaced apart side edges. The screen includes a multiplicity of reflective elements arranged in a plurality of vertical rows. Each row extends between the upper and lower edges of the screen. The plurality of rows are horizontally spaced and distributed between the pair of side edges. The elements of one row are displaced vertically with respect to the elements of an adjacent row and all of said element lie in a common plane so that the screen is flat. Each element has an optically active convex surface with a vertical generatrix and a curved horizontal directrix which crosses the generatrix at a center of the element.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: December 9, 1997
    Inventors: Pierre Leon A. Malifaud, Gerard Marcel Vuillaume
  • Patent number: 5690772
    Abstract: A method for mass-producing eccentric Fresnel lens sheets comprising the steps of: preparing a number of concentric Fresnel lens sheets; dividing the concentric Fresnel lens sheets into a first set and a second set each including a plurality of Fresnel lens sheets; cutting out a plurality of first sheets each corresponding to one portion of the eccentric Fresnel lens sheet from each of the Fresnel lens sheets of the first set; cutting out a plurality of second sheets each corresponding to the other portion of the eccentric Fresnel lens sheet from each of the Fresnel lens sheets of the second set; and bonding each of the first sheets and each of the second sheets in such a manner that patterns on the first sheet and the second sheet are continuous to prepare a plurality of eccentric Fresnel lens sheet. The second set can include a third set and a fourth set and a plurality of third sheets are cut out from the third set and a plurality of fourth sheets are cut out from the fourth set.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: November 25, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideaki Mitsutake, Nobuo Minoura, Katsumi Kurematsu, Haruyuki Yanagi
  • Patent number: 5657159
    Abstract: A video display apparatus has a dot matrix of LEDs mounted on an LED matrix board, and a unitary reflecting member made of metal such as aluminum or the like mounted on the LED matrix board. The reflecting member has slanted reflecting surfaces disposed vertically one on each side of each of the LEDs for reflecting light emitted from the LEDs with narrow vertical directivity. The video display apparatus can provide a wide angle of view in the horizontal direction, and a narrow angle of view in the vertical direction for preventing light from being scattered in the vertical direction to maintain a desired level of luminosity.
    Type: Grant
    Filed: January 24, 1996
    Date of Patent: August 12, 1997
    Assignee: Sony Corporation
    Inventor: Takehisa Natori
  • Patent number: 5638208
    Abstract: In a multiple-projector concave-screen display system, spacial alignment of images on the screen, is enabled by designating calibration points with retro-reflective dots and illumination markers. The manufacture of the screen involves locating calibration points and depositing the dots with a tool utilizing a rotary mechanism for loading and applying the dots from solenoid actuated pod units. Areas for retro-reflective dots, versus illumination markers, are defined on the basis of reflectance angles between vectors to the screen from a projector and from the screen to a viewer.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: June 10, 1997
    Assignee: Evans & Sutherland Computer Corporation
    Inventor: Joe L. Walker
  • Patent number: 5609939
    Abstract: A viewing screen for incident light including a sheet of embossable material in which a first micro-sculpted surface relief structure that controls the direction in which light propagates has been formed by replicating in the sheet of embossable material a second micro-sculpted surface structure that controls the direction in which light propagates, the second micro-sculpted surface structure having been formed in a photosensitive medium having a refractive index by (i) generating random, disordered and non-planar speckle in the photosensitive medium with coherent light which has been diffused through a holographic diffuser so as to define non-discontinuous and smoothly varying changes in the refractive index of the photosensitive medium which scatter collimated light into a controlled pattern with smooth brightness variation and (ii) developing the photosensitive medium, the incident light being incident on and returned from the viewing screen to a viewing area, the viewing screen controlling the direction o
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: March 11, 1997
    Assignee: Physical Optics Corporation
    Inventors: Joel Petersen, Jeremy Lerner
  • Patent number: 5589979
    Abstract: A screen simulator arrangement includes spaced apart screen and one or more mirror means; said screen means is formed with a plurality of spaced apart transparent portions therein; said mirror means is formed or provided with a plurality of holes or openings therein; said screen and said mirror means are fixedly located relative to each other; the transparent portions of said screen means and the holes or openings of said mirror means are substantially out of register one with the other. An inner screen surface of said screen means and a reflective surface of said mirror means generally face inwardly towards each other, said transparent portions of said screen means and said holes or openings of said mirror means being so out of register one with the other, such that screen portions of said screen means are in substantial alignment/register with holes or openings in said mirror means.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: December 31, 1996
    Assignee: Trutan Pty Limited
    Inventor: Donald L. M. Martin
  • Patent number: 5483308
    Abstract: This invention discloses a projection apparatus and method for displaying floor, ceiling, and wall coverings. A projector contained within a special projection tower and combined with retroreflective screens provide a means for manufactures to display coverings in a full size perspective even in normal ambient light.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: January 9, 1996
    Inventors: Ray Youngker, Henry J. Oles
  • Patent number: 5475533
    Abstract: A light control material generally comprising a transparent substrate for carrying a print or photographic image and a plurality of focusing elements which provide a field of view over which the brightness of the print or photographic image is enhanced. The field of view is controlled by the geometry of the focusing elements including radius, width, and degree of symmetry. By providing a field of view over which the brightness of the image is enhanced, the image may be viewed at angles which avoid the angles of specular reflection, which are usually seen as unwanted glare. Furthermore, selected portions of an image may be brightness enhanced more than others or selected portions may be brightness enhanced while others are not.
    Type: Grant
    Filed: August 2, 1993
    Date of Patent: December 12, 1995
    Assignee: Applied Physics Research, L.P.
    Inventors: Richard A. Steenblik, Mark J. Hurt, Samuel D. Shearman
  • Patent number: 5456967
    Abstract: A reflection-type screen that is free from uneven formation attributable to a weave pattern of a ground fabric as a constituent material, can be wound up in a roll form and unwound at need and is less likely to cause deformation, such as buckling, elongation and sagging, and is easy to handle. The reflection-type screen includes a dimensionally stable substrate sheet having an elastic limit of 60 kg/cm.sup.2 or more, a Young's modulus of elasticity of 2.5.times.10.sup.4 kg/cm.sup.2 or more, a bending modulus of elasticity of 3.5.times.10.sup.4 kg/cm.sup.2 or less, a thickness of 35 to 200 .mu.m and a center line average height and a waviness of 100 .mu.m or less each. Laminated on the substrate sheet in the following order is a high-density light diffusion-reflection layer and a translucent light diffusion layer including a soft vinyl chloride sheet, the translucent light diffusion layer having a surface provided with a light-diffusing fine uneven pattern.
    Type: Grant
    Filed: September 29, 1993
    Date of Patent: October 10, 1995
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Michiko Nezu
  • Patent number: 5418584
    Abstract: A retroreflective array projection screen for displaying virtual images wherein the apparent distances from the observer to the viewed subject is greater than the distance from the observer to the retroreflective screen. Real images from a source are collimated and then partially reflected onto the retroreflective array. Virtual images are reflected from the array through the beamsplitter onto an observer at an exit pupil.
    Type: Grant
    Filed: December 31, 1992
    Date of Patent: May 23, 1995
    Assignee: Honeywell Inc.
    Inventor: Brent D. Larson
  • Patent number: 5414558
    Abstract: A screen is used for a projector and includes a metal plate body and a plurality of elongated parallel streaks. The metal plate body has a concave reflection surface which is horizontally straight and vertically curved and which has a predetermined radius of curvature. The streaks protrude uniformly and densely from the reflection surface of the metal plate body and extend from the top end of the reflection surface to the bottom end of the reflection surface in a generally vertical direction. Any adjacent pair of the streaks are sized and spaced apart from each other at an interval of less than 5 microns so that the streaks function as a concave grating. The concave reflection surface is coated with a transparent film by immersing the metal plate body in a caustic solution so as to decrease interference from light sources other than the projector.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: May 9, 1995
    Inventor: Shy-Loong You
  • Patent number: 5361163
    Abstract: A reflection type projection screen is constituted as follows. Provided in order on a light absorbing layer 5, which is a dark plastic sheet or a solid print of a dark ink, are a fibrous sheet 4 of glass fibers, a white, opaque base material sheet 3made with a plastic sheet, and a light diffusing layer 2 of a translucent plastic into which a lustrous pigment or calcite powder is incorporated. An emboss 9 is formed on the outer surface of the light diffusing layer 1. It is preferable that a reflection layer 2 printed with an ink containing a lustrous pigment or calcite powder is provided below the light diffusing layer 1. Light absorbing stripes 11 are provided each at a position corresponding to a concave portion 9a of the emboss 9 on the surface of the base material sheet 3 adjoining the light diffusing layer 1. A production process and a production apparatus of a reflection type screen, which can efficiently produce reflection type screens with the emboss are also disclosed.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: November 1, 1994
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventors: Noriaki Matsuda, Keiji Hanamoto
  • Patent number: 5323477
    Abstract: A compact array imager including image generation apparatus providing a real image at an inlet of an optical image waveguide. The real image being reflected a plurality of times within the optical image waveguide by diffractive optical elements that magnify and filter the real image and produce a virtual image at a viewing aperture The imager further includes electronics mounted on the sides of the optical image waveguide and coupled to the image generation apparatus by embedded molded signal waveguides for receiving signals representative of an image and controlling the apparatus to generate the image.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: June 21, 1994
    Assignee: Motorola, Inc.
    Inventors: Michael S. Lebby, Karen E. Jachimowicz
  • Patent number: 5296965
    Abstract: A screen of reflection-type operable with linearly polarized imagewise rays of light projected thereon for presenting a projected image, carried by the linearly polarized imagewise rays of light (8), to viewers occupying a position in front of the screen. The screen comprises a polarizing film (6) having first and second surfaces, a metal layer (4) formed on the second surface of the polarizing film (6) for reflecting the linearly polarized imagewise rays of light (8), and an indentation structure formed on both of the metal layer (4) and the polarizing film (6) for reflecting the imagewise rays of light (8) uniformly at a desired angle of reflection. The linearly polarized imagewise rays of light (8) enter the polarizing film (6) through the first surface thereof while the linearly polarized rays of light (8) have a plane of vibration of an electric field or a magnetic field in a direction required to exhibit a maximum light transmissivity.
    Type: Grant
    Filed: January 11, 1993
    Date of Patent: March 22, 1994
    Assignee: Kuraray Co., Ltd.
    Inventors: Masao Uetsuki, Satoshi Hirofuji, Yasuhira Takeuchi
  • Patent number: 5210641
    Abstract: Disclosed is a front projection display screen formed from a multiplicity of optical cells juxtaposed to define a surface. Each of the cells comprises a directional filter and light converging optics. The directional filter, which covers substantially all of the face of the optical cell, is adapted to pass light from the direction of the projector and to absorb light from other directions except at a small, transparent return aperture. The light converging optics are adapted to focus the substantially parallel light from the projector at the return aperture part of the directional filter and to spread it into a large solid angle. The combination provides an image of improved visual contrast by absorbing background light and returning image light to viewers.
    Type: Grant
    Filed: May 1, 1992
    Date of Patent: May 11, 1993
    Inventor: Richard B. Lewis
  • Patent number: 5186780
    Abstract: A transmission type screen having a screen body constituted by at least one plastic sheet formed of a multiplicity of transparent plastic strands arranged in the shape of a sheet, each the strands being welded together at outer surfaces thereof. Each of the transparent strand may have a main portion and another portion different from the main portion in terms of optical effects. This transmission type screen is manufactured by spinning off the transparent strands from a spinning nozzle while aligning the strands; welding each adjacent over of the strands to form a sheet; and forming a screen body from at least one sheet obtained in this manner.
    Type: Grant
    Filed: November 27, 1989
    Date of Patent: February 16, 1993
    Assignee: Mitsubishi Rayon Co.
    Inventors: Kenichi Sakunaga, Mizuo Okada
  • Patent number: 5130846
    Abstract: A dome-shaped motion picture projection screen is constructed from an external supporting frame and a plurality of panels that are clipped to the frame by a series of individual fasteners that are hooked into the perforations in the panel and clamped to the frame. Each fastener has a L-shaped fastener body with a pair of hook-shaped pins that project from one end of one limb so that they can be hooked into the perforations in the panel. A screw extends through the other limb parallel to the first limb and can be tightened against a supporting frame member to secure the panel to the frame. By carefully controlling tightening of the screw, localized flattening of the panel at the positions of the hooks can be avoided. The ends of the hooks are so small as to be virtually invisible to the audience.
    Type: Grant
    Filed: July 11, 1991
    Date of Patent: July 14, 1992
    Assignee: Imax Corporation
    Inventor: Kevin P. Kowalchuk
  • Patent number: 5121252
    Abstract: A projection screen is comprised of a sheet formed by a multiplicity of light-transmitting plastic strands which strands are arranged and welded in parallel with one another. The width W (mm) of the screen and the pitch p (mm) of the strands meet the following condition (1):0.03.ltoreq.p.ltoreq.W/1000 (1)The radius of curvature R.sub.1 (mm) of the strand at a first side of the screen is determined by the following condition (2)0.5.times.p.ltoreq.R.sub.1 .ltoreq.p (2)The radius of curvature R.sub.2 (mm) of the strand at a second side of the screen meets the following condition(3):R.sub.2 .ltoreq.R.sub.1 (3).
    Type: Grant
    Filed: April 26, 1991
    Date of Patent: June 9, 1992
    Assignee: Mitsubishi Rayon Co., Ltd.
    Inventors: Mizuo Okada, Kenichi Sakunaga, Shigetada Nakagawa, Shozo Saito
  • Patent number: RE36740
    Abstract: In a cata-dioptric optical system having a combination of a reflection system and a refraction system for reduction-projecting an object on a first plane onto a second plane, a polarization beam splitter and a quarter wavelength plate are provided to split the incident light and the reflected light. The light beam directed to the polarization beam splitter is converted to a substantially collimated light beam by a first group of lenses. A second group of lenses are arranged between the polarization beam splitter and a concave reflection mirror to diverge the light beam. The light reflected by the concave reflection mirror is directed back to the polarization beam splitter with a substantially collimated state by the second group of lenses. The light beam from the second group of lenses transmitted through the polarization beam splitter is focused by a third group of lenses having a positive refraction power to form a reduced image.
    Type: Grant
    Filed: June 14, 1995
    Date of Patent: June 20, 2000
    Assignee: Nikon Corporation
    Inventors: Yutaka Ichihara, Hideo Mizutani, Sumio Hashimoto, Yutaka Suenaga