Patents Examined by Tiep H. Nguyen
  • Patent number: 5638203
    Abstract: The present invention relates to obtain an electrooptical device having a high response speed by using a spontaneously polarized ferroelectric liquid crystal. Spontaneously polarized ferroelectric liquid crystal in the smectic-A state is sealed into a proper transparent case. An electric field is applied perpendicularly to a light path direction so as to change the orientation directions of liquid crystal molecules, thereby changing the refractive index distribution. A liquid crystal electrooptical device having both deflection and focusing functions is provided by adjusting the shape of the electrodes while maintaining the polarization state of an input light beam.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: June 10, 1997
    Assignee: International Business Machines Corporation
    Inventors: Masaki Hasegawa, Fuminori Sai, Fumiaki Yamada
  • Patent number: 5636044
    Abstract: A display device (110) having first and second substrates (112) and (190) and a layer of a liquid crystal material having a periodic modulated structure, such as a PSCT or PFCT liquid crystal material disposed therebetween. The first substrate is divided into segment and non-segmented areas which are defined by a gap in the electrode materials disposed on the substrate. Similarly, the second substrate (190) is divided into common electrodes corresponding to the segmented and non-segmented areas on the first substrate.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: June 3, 1997
    Assignee: Kent Displays, Inc.
    Inventors: Haiji Yuan, George Ventouris
  • Patent number: 5636041
    Abstract: Method and apparatus for automatically increasing the visibility of an LCD during warm-up thereof is disclosed. In a preferred embodiment, the system of the present invention comprises brightness control circuitry electrically connected to an LCD panel of a portable personal computer (PC) or other battery operated electronic device for controlling the brightness level of the LCD. The brightness control circuitry is also electrically connected to receive a signal indicative of a brightness control level selected by a user using a user-settable control means, such as a brightness control knob located on the device. In operation, on power up of the LCD, the brightness control circuitry increases the LCD brightness to a maximum level, regardless of the brightness level selected by the user. Once the LCD has warmed up, the brightness control circuitry decreases the brightness level of the LCD to the level selected by the user.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: June 3, 1997
    Assignee: Dell USA, L.P.
    Inventors: John J. Pearce, Philip Chidester
  • Patent number: 5631754
    Abstract: Systems and methods for shaping light from a liquid crystal display are described. A holographic high contrast viewing screen embedded in a liquid crystal display includes a first substrate; a first electrode connected to said first substrate; a light shaping holographic surface relief diffuser connected to said first electrode, said light shaping holographic surface relief diffuser having a first orientation and a first refractive index; a liquid crystal adjacent said light shaping holographic surface relief diffuser, the liquid crystal having a second refractive index that is substantially equal to the first refractive index, in the absence of a driving voltage applied to the first electrode and the second electrode; an alignment layer adjacent said liquid crystal, said alignment layer having a second orientation that is substantially orthogonal to said first orientation; a second electrode connected to said alignment layer; and a second substrate connected to said second electrode.
    Type: Grant
    Filed: October 20, 1995
    Date of Patent: May 20, 1997
    Assignee: Physical Optics Corporation
    Inventors: Tomasz P. Jannson, Tin M. Aye, Jeremy Lerner
  • Patent number: 5629786
    Abstract: A liquid crystal display device has a liquid crystal layer having super twisted nematic liquid crystal with a twist angle of 260.degree., the liquid crystal layer being sandwiched between a first substrate and a second substrate. A color filter is formed on the second substrate. The first substrate is orientation-processed so that pretilt angles of the liquid crystal to the first substrate are 5.5.degree.. The second substrate is orientation-processed so that pretilt angles of the liquid crystal to the second substrate are 3.0.degree.. Therefore, it is possible to easily reduce occurrence rate of inadequate display and, at the same time, to maintain beneficial characteristics of a liquid crystal display device with a twist angle of 250.degree. or more, i.e., a good temperature characteristic, a small contrast change against a temperature change, and good quality display.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: May 13, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masami Ogura, Masayuki Yamanaka, Hiroshi Takanashi
  • Patent number: 5625474
    Abstract: A full-color liquid crystal display device is provided which includes: a first substrate formed with a plurality of liquid crystal driving active elements; and first, second and third liquid crystal cells stacked one on another on an inter-layer film formed on the first substrate; the first liquid crystal cell including a first liquid crystal driving electrode connected to a first liquid crystal driving active element formed on the first substrate; the second liquid crystal cell formed on the second substrate and including a second liquid crystal driving electrode connected to a second liquid crystal driving active element formed on the first substrate via a lower stereo-interconnection extending through the first liquid crystal cell; the third liquid crystal cell formed on the third substrate and including a third liquid crystal driving electrode connected to a third liquid crystal driving active element formed on the first substrate via another lower stereo-interconnection extending through the first liquid
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: April 29, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shigeru Aomori, Atsushi Tanaka, Seiichi Mitsui
  • Patent number: 5615028
    Abstract: A liquid crystal display apparatus includes a first substrate, a second substrate having a counter electrode, and a liquid crystal layer sandwiched between the first substrate and the second substrates. The first substrate includes: a plurality of pixel electrodes arranged in a matrix; a plurality of source bus lines for transmitting a plurality of data signals, each data line being disposed between columns of the plurality of pixel electrodes; a plurality of active elements for electrically connecting each of the plurality of pixel electrodes to its adjacent source bus line and thereby feeding the plurality of data signals to the plurality of pixel electrodes; and a plurality of gate bus lines for transmitting scanning signals for controlling the plurality of active elements so as to be in a conductive or non-conductive state, each gate bus line being disposed between rows of the plurality of pixel electrodes.
    Type: Grant
    Filed: March 21, 1995
    Date of Patent: March 25, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kenichi Ishiguro, Masahiro Adachi
  • Patent number: 5612797
    Abstract: A liquid crystal projection display system includes a liquid crystal display panel (7) which is illuminated by light directed at a small angle (A) to its normal for display contrast enhancement. To reduce defocussing and distortion effects, the panel is tilted with the normal to its plane at an angle (B) to the axis of the projection lens smaller than the illumination angle (A) and a deflector element is disposed between the panel and the projection lens for deflecting the panel output beam so that it is directed generally parallel to the projection lens axis. The panel may be operated in a reflective mode or a transmissive mode. In the latter case, a further deflector element may be disposed adjacent the input side of the panel allowing the axis of illuminating light beam to be arranged parallel with the projection lens axis.
    Type: Grant
    Filed: May 11, 1995
    Date of Patent: March 18, 1997
    Assignee: U.S. Philips Corporation
    Inventor: John A. Clarke
  • Patent number: 5610738
    Abstract: An active matrix liquid crystal display device, with a plurality of thin-film transistors provided over a glass substrate each including an anodized oxide film of aluminum gate electrode, in which transparent pixel electrodes are formed in the same plane as the gate electrodes between the glass substrate and amorphous silicon islands over which source and drain electrodes are provided. In such a device structure, in which the spacing between the ITO and the gate electrode can be compacted while ensuring that there are no short-circuits effected between the ITO layer and gate electrode during the manufacture of the LCD device, the gate electrode and, therefore, also the plate (lower) electrode of the capacitor Cadd are first formed, followed by the formation of the AOF layer over the gate electrode and over the plate electrode of the capacitor, respectively.
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: March 11, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Akira Sasano, Kazuo Shirahashi, Yuka Matsukawa, Hideaki Taniguchi, Hideaki Yamamoto, Haruo Matsumaru
  • Patent number: 5608559
    Abstract: A display board has wirings on a surface thereof for transmitting a signal received from outside at a peripheral portion of the display board to a display area of the display board. Each wiring has a first conductive film formed of a first material and disposed on the surface of the display board, a second conductive film which is formed of a second material satisfying a condition that a surface of the second conductive film is less prone to oxidation than a surface of the first conductive film and which is disposed on a part of the first conductive film, and a transparent conductive film which is an oxide film and which is disposed on at least the second conductive film. Those first conductive film, second conductive film and transparent film constitute a three-layered structure portion of the wiring.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: March 4, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kiyoshi Inada, Motoji Shiota, Hirokazu Yoshida, Yasunobu Tagusa
  • Patent number: 5598121
    Abstract: A switching circuit for outputting input and output signals from a single terminal includes an I/O signal interface circuit for forming a current path in parallel with a switch when a voltage at both terminals of the switch changes from high state to low state and for opening the current path when receiving a delay signal. An I/O signal separator provides the delay signal of predetermined time width when forming the current path to the I/O signal interface circuit and for blocking the current path during the delay period. Repeated and consecutive striking of a singular switch is ignored since only the first strike is effective. In addition, a display connected to a previously pressed switch remains continuously lighted when an interval between two consecutive struck different switches is shorter than the delay period.
    Type: Grant
    Filed: September 27, 1993
    Date of Patent: January 28, 1997
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Myung-Hyun Nam
  • Patent number: 5594591
    Abstract: A dichroic mirror is formed on a surface of a prism except an incident surface for reflecting an entered ray having a predetermined wavelength. An optical thin film is formed on the incident surface as to totally reflect the ray reflected from the dichroic mirror. The optical thin film has a phase control function.
    Type: Grant
    Filed: February 1, 1995
    Date of Patent: January 14, 1997
    Assignee: Pioneer Electronic Corporation
    Inventors: Hideki Yamamoto, Naruhiko Atsuchi
  • Patent number: 5594569
    Abstract: A liquid crystal device comprising:a pair of substrates having an electrode arrangement thereon; an orientation control means provided on at least one of said substrates; and a ferroelectric or antiferroelectric liquid crystal layer interposed between said substrates, said liquid crystal layer being uniaxially oriented by virtue of said orientation control means, wherein means for suppressing an orientation control effect of said orientation control means with respect to said liquid crystal layer is provided between said liquid crystal layer and said orientation control means.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: January 14, 1997
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Toshimitsu Konuma, Takeshi Nishi, Michio Shimizu, Harumi Mori, Kouji Moriya, Satoshi Murakami
  • Patent number: 5589960
    Abstract: A double-layer type super-twisted nematic liquid crystal display system including a liquid crystal display device for displaying characters and/or graphic forms, a compensating liquid crystal device for compensating the optical phase of the liquid crystal display device, a temperature sensor for detecting the ambient temperature of those devices, a light sensor for calculation of the display contrast of the liquid crystal display device, drive voltage control circuits for controlling the drive voltages applied to the liquid crystal display device and the compensating liquid crystal device, and a displaying light source. In the display system, the drive voltages applied to the liquid crystal display device and compensating liquid crystal device are adjusted according to the calculation of contrast, whereby the display is high in contrast at all times independently of the ambient temperature.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: December 31, 1996
    Assignee: Kansei Corporation
    Inventors: Masao Chiba, Mikio Ishii
  • Patent number: 5587821
    Abstract: It is an object of the invention to improve the viewing angle properties of a liquid crystal display device by controlling the state of orientation of liquid crystal molecules. The liquid crystal display device is constructed with an liquid crystal display element disposed between a pair of polarizing plates, and with phase difference plates disposed between each polarizing plate and the liquid crystal display element. The phase difference plates are selected so that nx.gtoreq.nz>ny is satisfied and the Nz value is in the range of 0.ltoreq.Nz.ltoreq.0.5. The liquid crystal display element is constructed by placing a liquid crystal layer between substrate members prepared by forming transparent electrodes and orientation films in the pair of light transmitting plates, and the liquid crystal layer sandwiched between the transparent electrodes is used as picture elements.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: December 24, 1996
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroko Nakanishi, Hiroshi Ohnishi
  • Patent number: 5587819
    Abstract: A reflective direct-view type display device including a first substrate having two major surfaces and electrode provided on a first major surface, a second substrate having two major surfaces and color filter layers and pixel electrodes provided on a first major surface, a light-scattering medium interposed between the first and second substrates positioned with the electrode opposes the pixel electrodes, and at least one color filter layer provided on the first major surface of the first substrate and apposing at least one of the color filter layers provided on the first major surface of the second substrate. The display can produce high-luminance colors, by using external light at high efficiency and with a low consumption of electric power.
    Type: Grant
    Filed: December 27, 1994
    Date of Patent: December 24, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyuki Sunohara, Rei Hasegawa, Hiroyuki Nagata, Shinichi Sanada, Yasushi Kawata
  • Patent number: 5585951
    Abstract: An active-matrix substrate has a layered structure in which an upper region including a plurality of pixel electrodes arranged in a matrix and a lower region including a plurality of thin film transistors for driving the individual pixel electrodes are overlapped on each other. A planarization layer is interposed between both of the substrates. An active-matrix liquid crystal display device includes a main substrate and a facing substrate which are disposed to face to each other at a specified interval. A liquid crystal layer having a specified thickness is held between both of the substrates. A device bus line area including a plurality of thin film transistor devices and bus lines is formed on the surface of the main substrate. A planarization layer is formed to embed the irregularities on the surface of the device bus line area. Pixel electrodes in a matrix are formed on the flat surface of the planarization layer.
    Type: Grant
    Filed: December 23, 1993
    Date of Patent: December 17, 1996
    Assignee: Sony Corporation
    Inventors: Kazuhiro Noda, Shinji Nakamua, Hisao Hayashi, Hisashi Kadota
  • Patent number: 5583462
    Abstract: A method and apparatus for rapidly measuring chemical properties of a solution using a plurality of devices having relatively long thermal time constants selectively coupled to a control means. Current I.sub.d flows through only one device at a time. A timing logic control circuit controls the timing of the drain switch and, if present, the reference switch. The output of the multiplexing circuit is sampled a precise amount of time after each device begins conducting current. The temperature at the sample time is a constant. The characteristics of the solution in which the device is immersed is the only variable in the operation of the device (i.e., I.sub.d, and V.sub.ds are held constant). By sampling the output a predetermined amount of time after the device has been turned on, the temperature rise is controlled.
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: December 10, 1996
    Assignee: Unifet Incorporated
    Inventor: Eric Grasshoff
  • Patent number: 5583678
    Abstract: A pair of polarizing plates are disposed on two sides of a TN-type liquid crystal cell constituted by a liquid crystal twist-aligned at a twist angle of 80.degree. to 120.degree.. A retardation plate is disposed between one of the polarizing plates and the liquid crystal cell in such a manner that the optical axis of the retardation plate crosses the transmission axis of the adjacent polarizing plate at 45.degree.. The pair of polarizing plates are arranged such that their transmission axes are parallel to each other. The liquid crystal cell is arranged such that the optical axis of the retardation plate crosses the aligning direction of the liquid crystal molecules on the substrate side adjacent to the retardation plate at 45.degree.. A liquid crystal driving circuit is connected to the liquid crystal. This circuit serves to change the voltage applied to the liquid crystal to change the polarized state of light transmitted through the liquid crystal so as to change the color of emerging light.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: December 10, 1996
    Assignee: Casio Computer Co., Ltd.
    Inventors: Toshiharu Nishino, Yasushi Nishida, Masayuki Takahashi
  • Patent number: 5583682
    Abstract: A liquid crystal device for gradational display, comprising: a pair of substrates each provided with an electrode, and a liquid crystal layer comprising a chiral smectic liquid crystal disposed between the substrates; the pair of substrates each having thereon alignment control layer provided with a uniaxial alignment axis, wherein aid liquid crystal layer comprises a striped region and a non-striped region where (1) the striped region and the non-striped region each assume a homogeneous alignment state, (2) the striped region extends in a direction perpendicular to the direction of the uniaxial alignment axis, and (3) each of liquid crystal molecules within the striped region and the non-striped region show bistability; and the liquid crystal molecules within the striped region have a threshold voltage, for switching between two stable states, different from that given by the liquid crystal molecules within the on-striped region.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: December 10, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroyuki Kitayama, Kenji Shinjo, Syuji Yamada