Patents Examined by Richard Gallivan
  • Patent number: 4913531
    Abstract: A liquid crystal light valve is provided with a microgrid of grooves in the photoconductor surface to divide the photoconductor into high resolution pixels. The liquid crystals fill the grooves to seal them and contribute to a potential barrier at the grooves that prevents lateral charge migration between pixels. In a metal oxide semiconductor (MOS) embodiment an oxide layer extends over the pixels and partially overhangs the grooves. A metal matrix mirror is formed over the insulative layer, and extends into a portion of the grooves to shield the underlying silicon from photoactivation while maintaining an electrical isolation between pixels.
    Type: Grant
    Filed: September 7, 1988
    Date of Patent: April 3, 1990
    Assignee: Hughes Aircraft Company
    Inventors: Uzi Efron, Murray S. Welkowsky, Norman W. Goodwin
  • Patent number: 4906071
    Abstract: The invention relates to a liquid crystal display device and a projection TV using same. The liquid crystal display device has microfine conductive bumps formed on terminals of a liquid crystal display panel, and a conductive joint layer formed on each conductive bump. The display panel is connected to wiring leads formed on a substrate provided thereon an IC drive circuit. The projection TV employs a liquid crystal display device in which three liquid crystal display panels corresponding to three colors, red, green, and blue, are mounted on a single substrate. Light beams are made incident on the respective panels, and light beams transmitted through or reflected from specified pixels are projected on a screen to form an image.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: March 6, 1990
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Takahara, Hitoshi Noda, Mamoru Takeda, Yoshito Miyatake, Yasuhiro Horio
  • Patent number: 4906074
    Abstract: A liquid crystal display comprises a pair of substrates provided with an electrode arrangement in matrix form, A chiral smectic C phase liquid crystal material is interposed between the substrates. In the liquid crystal layer, each pixel consists of a number of micro-domains which can be compared to polycrystal line structures. Interaction between adjacent pixels through well ordered liquid crystal structure is suppressed by virtue of the micro-domains.
    Type: Grant
    Filed: September 28, 1988
    Date of Patent: March 6, 1990
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Masahiko Sato
  • Patent number: 4904060
    Abstract: In a reflector-diffuser type liquid crystal display cell, the control electrodes, which are transparent, electronic components and tracks connecting the components to the cell terminals are disposed between the cell front plate and the liquid crystal layer. The counter electrode is disposed on the other side of the liquid crystal layer and has a frosted rough light reflecting and diffusing face over its entire surface situated in the display area and thus itself functions as the cell reflector-diffuser.
    Type: Grant
    Filed: November 22, 1988
    Date of Patent: February 27, 1990
    Assignee: Asulab, S.A.
    Inventor: Joachim Grupp
  • Patent number: 4904061
    Abstract: A projection-type display device for producing a faithful colored synthesized image based on equating the luminous intensity distributions and light patterns produced by three twisted nematic liquid crystal light valves for three primary color images. Each light valve includes a twisted nematic liquid crystal composition which is twisted to the right or left depending on the number of times that color light is reflected. Each light valve may include an active switching matrix arranged in mirror-like symmetry with light shield layers also arranged symmetrically.
    Type: Grant
    Filed: April 14, 1989
    Date of Patent: February 27, 1990
    Assignee: Seiko Epson Corporation
    Inventor: Shuji Aruga
  • Patent number: 4902106
    Abstract: Bistable ferroelectric smectic liquid crystal display device.This device comprises a tight cell inserted between two polarizers formed from two glass walls, each provided with a display-appropriate electrode connected to an electric power supply for applying an electric field for controlling the liquid crystal to a chiral ferroelectric smectic liquid crystal film inserted between the electrodes. To obtain bistability and storage of the liquid crystal, one of the walls is covered with a material constituted by a stack of a silica layer, a polyimide layer, an optionally rubbed organosilane film in contact with the liquid crystal and the other wall is provided with a silica film covered with a Nylon film.
    Type: Grant
    Filed: March 30, 1988
    Date of Patent: February 20, 1990
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Jean Dijon, Christine Ebel
  • Patent number: 4895432
    Abstract: A display device including a pair of opposed substrates at least one of which is transparent with a display medium layer therebetween, and a transparent electrode arranged on the internal surface of the transparent substrate is provided. The thickness of the transparent electrode is about ((5500.times.N)/(2.times.n)).ANG. wherein N is a natural number and n represents the refractive index thereof. When a transparent insulating film is formed on the transparent electrode, the thickness of the transparent insulating film is about ((5500.times.N)/(2.times.m)).ANG. wherein N is a natural number and m represents the refractive index thereof. When the refractive index of n.sub.1 of the transparent insulating film is substantially equal to the refractive index n.sub.2 of the transparent electrode, the value, 2.times.(n.sub.1 .times.d.sub.1 +n.sub.2 .times.d.sub.2) equals about (5500.times.N).ANG. wherein N is a natural number, d.sub.1 represents the thickness of the transparent insulating film and d.sub.
    Type: Grant
    Filed: April 8, 1988
    Date of Patent: January 23, 1990
    Assignee: Seiko Epson Corporation, a Japanese Corporation
    Inventors: Yukihiro Iwashita, Koji Sumi, Koichi Kamijo, Hideaki Okumura
  • Patent number: 4892390
    Abstract: A multi-layered liquid crystal display device is disclosed, which includes a stack of liquid crystal layers in which the longitudinal axes of the liquid crystal molecules extend spirally, the liquid crystal layers being disposed in parallel with the spiral axes. A voltage supply is provided for supplying a voltage to at least a portion of the liquid crystal layers for conversion of the molecular alignment. Also provided is a pair of polarizers for making visible the conversion of the molecular alignment. More particularly, the polarization direction of the polarizers or direction normal to the polarization direction is deflected within the range of 3.degree. to 15.degree. with respect to the longitudinal direction of the liquid crystal molecules in a sense to reduce the spiral angle of the liquid crystal layers and the deflection angle is substantially in alignment with the longitudinal direction of the liquid crystal molecules.
    Type: Grant
    Filed: February 7, 1989
    Date of Patent: January 9, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Fumiaki Funada, Masataka Matsuura, Tomio Wada
  • Patent number: 4889412
    Abstract: Liquid crystal cell using the electrically controlled birefringence effect and processes for the production of the cell and a uniaxial medium or material of negative optical anistropy usable therein.The cell can comprise two crossed rectilinear polarizers, two glass plates provided with transparent electrodes and placed between said polarizers, a liquid crystal layer between the plates and, between a plate and a polarizer, a layer of a negative uniaxial thermoplastic polymer having its extraordinary axis perpendicular to the plates. This layer can be obtained by heating the polymer up to the isotropic state, under a uniform presure on the polarizers, cooling and eliminating the pressure. Application to the production of data display devices.
    Type: Grant
    Filed: February 17, 1987
    Date of Patent: December 26, 1989
    Assignee: Commissariat A l'Energie Atomique
    Inventors: Jean-Frederic Clerc, Jean-Claude Deutsch, Pierre Vaudaine, Sylvie Vey
  • Patent number: 4886343
    Abstract: A liquid crystal display unit is described in which a first panel of pixel elements is used to control red and green portions of a displayed image using an additive technique while a second panel, having pixels aligned with the first panel pixels, controls the blue portion of the image through subtractive techniques. The resulting display system can provide enhanced brightness, resolution and color characteristics. The display system makes use of the fact that the eye is less sensitive to blue radiation for several visual parameters. As a result of the decreased sensitivity, the second (blue) panel can operate with less stringent requirements.
    Type: Grant
    Filed: June 20, 1988
    Date of Patent: December 12, 1989
    Assignee: Honeywell Inc.
    Inventor: Michael J. Johnson
  • Patent number: 4884873
    Abstract: A liquid crystal apparatus includes a plurality of volumes of liquid crystal material in a containment medium. At least some of the volumes are interconnected. The walls defining the volumes tend to distort the natural liquid crystal structure in the absence of an electric field, and the optical and electrical properties of the materials are such that in the absence of a field incident light is scattered or absorbed and in the presence of a field, scattering and/or absorption are reduced. The apparatus may be used in an optical display, optical shutter, billboard, etc., and it functions independently of polarization. Methods of making and using the apparatus also are included in the invention.
    Type: Grant
    Filed: October 27, 1987
    Date of Patent: December 5, 1989
    Assignee: Manchester R & D Partnership
    Inventor: James L. Fergason
  • Patent number: 4884874
    Abstract: An electron beam addressed liquid crystal light modulator or "valve" (10) includes a liquid crystasl cell (40) having a target surface (45) which a writing electron beam (60a) and an erasing electron beam (60b) address to provide a display image. The writing electron beam and the erasing electron beam sequentially strike preselected locations on the target surface to cause an emission of secondary electrons and, thereby, develop an electrostatic potential at such preselected locations. A secondary electron collector electrode (66) positioned over and above the target surface collects in a uniform manner the secondary electrons emitted by all regions of the target surface. A collector electrode controller circuit (81) sequentially applied first and second potential differences between the target surface and the collector electrode in synchronism with the striking of the preselected locations by the respective writing and erasing beams.
    Type: Grant
    Filed: July 14, 1988
    Date of Patent: December 5, 1989
    Assignee: Tektronix, Inc.
    Inventors: Thomas S. Buzak, Rolf S. Vatne
  • Patent number: 4884877
    Abstract: The present invention relates to liquid crystal temperature indicating compositions, preferably absent cholesteric liquid crystal material, and the containing of such compositions in volumes formed in a containment medium that tends to distort the liquid crystal structure when the temperature thereof is below a transition or clearing point temperature. The containment medium is water resistant, e.g. insoluble in water, and preferably has heat and optical stability, e.g. does not brown or otherwise discolor, at relatively high temperatures, e.g. above 100.degree. C. Plural liquid crystal materials having different transition temperatures may be mixed to form a liquid crystal material having a transition temperature intermediate those of the ingredients.
    Type: Grant
    Filed: January 22, 1986
    Date of Patent: December 5, 1989
    Assignee: Manchester R & D Partnership
    Inventor: James L. Fergason
  • Patent number: 4884875
    Abstract: A light-addressed liquid crystal light valve comprises a transparent insulating substrate having either one-dimensional or two-dimensional arrays of light switching elements thereon which can perform switching with an incident light, another opposing transparent substrate having transparent electrodes and a liquid crystal sandwiched therebetween. Each of the light switching elements comprises a voltage divider circuit and an inverter circuit. The voltage divider circuit comprises a photoconductor element and a resistor element. The inverter circuit receives as input the voltage divided by the voltage divider circuit, while the output voltage from the inverter circuit is applied to one pixel electrode for the liquid crystal.
    Type: Grant
    Filed: October 6, 1988
    Date of Patent: December 5, 1989
    Assignee: NEC Corporation
    Inventor: Fujio Okumura
  • Patent number: 4883344
    Abstract: A liquid crystal device comprises a pair of parallel substrates and a ferroelectric liquid crystal disposed between the substrates so as to have an arrangement of molecules forming a plurality of layers perpendicular to the faces of the substrates. At least one of the pair of substrates has an alignment control film formed of a modified polyvinyl alcohol resin having a function of aligning said plurality of layers preferentially in one direction. The modified polyvinyl alcohol resin film stably provides a uniform alignment state with a large tilt angle than a conventional alignment control film of polyimide or unmodified polyvinyl alcohol.
    Type: Grant
    Filed: January 24, 1989
    Date of Patent: November 28, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinjiro Okada, Kazuo Yoshinaga, Osamu Taniguchi, Hideyuki Kawagishi, Akira Tsuboyama, Yukio Hanyu, Masataka Yamashita, Kazuharu Katagiri
  • Patent number: 4872741
    Abstract: A light transmissive liquid crystal display is illuminated from its rear surface by a juxtaposed flat electrodeless discharge lamp. The lamp includes a pair of glass plates sealably enclosing a fill gas. The front plate carries a phosphor coating on its interior surface and the rear plate carries a phosphor coating and a reflective film. A rectangular array of RF coils behind the rear plate provides excitation for a plasma arc discharge within the fill gas whereby adjacent discharge current paths counter rotate. Ultraviolet radiation emitted by the plasma arc discharge excites the phosphor which produces visible light of uniform brightness that may be varied by varying the RF current amplitude in the coils.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: October 10, 1989
    Assignee: General Electric Company
    Inventors: James T. Dakin, Sayed A. El-Hamamsy
  • Patent number: 4859036
    Abstract: A device plate is provided which comprises a transparent conductive film comprised of indium oxide, and laminated thereon a metallic conductive film comprised of at least one metal selected from the group consisting of molybdenum, titanium, chromium, tantalum, tungsten and nickel.
    Type: Grant
    Filed: May 12, 1988
    Date of Patent: August 22, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumie Yamanaka, Takashi Enomoto, Toshifumi Yoshioka
  • Patent number: 4850678
    Abstract: The present invention relates to use of liquid crystal material encapsulated in a containment medium to produce a controlled colored output, for example, in response to the application, removal and variation in an electric field. In one embodiment a non-pleochroic dye is in the containment medium itself and in another embodiment the non-pleochroic dye is in the liquid crystal material itself; and in both cases the object is to color light.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: July 25, 1989
    Assignee: Manchester R & D Partnership
    Inventor: James L. Fergason
  • Patent number: 4844596
    Abstract: Encapsulated operationally nematic liquid crystal is contained in plural volumes formed by a containment medium. The volume walls tend to distort the natural structure of the liquid crystal in the absence of a prescribed input, such as an electric field; the liquid crystal structure tends to align in parallel in the presence of such prescribed input. An additive, for example a chiral additive, in the liquid crystal tends to expedite return to distorted alignment upon removal of the prescribed input. Moreover, an additive can be employed to cause the liquid crystal structure near the wall of the containment medium to be oriented approximately normal to the wall when in distorted or random alignment in the absence of the prescribed input.
    Type: Grant
    Filed: March 19, 1986
    Date of Patent: July 4, 1989
    Assignee: Manchester R & D Partnership
    Inventor: James L. Fergason
  • Patent number: RE33120
    Abstract: A method for driving a liquid crystal element including a ferroelectric liquid crystal sandwiched between a pair of substrates having electrodes on their opposite surfaces is disclosed. A pulse voltage for defining the light transmitting state of the liquid crystal element is applied to the ferroelectric liquid crystal. Before and/or after the application of the pulse voltage, the ferroelectric liquid crystal is applied with a voltage signal which renders the average value of voltages applied to the ferroelectric liquid crystal equal to zero.
    Type: Grant
    Filed: April 1, 1987
    Date of Patent: November 28, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Yoshiharu Nagae, Masato Isogai, Hideaki Kawakami, Fumio Nakano