Changing Liquid Crystal Phase Patents (Class 349/188)
  • Patent number: 6020947
    Abstract: A ferroelectric liquid crystal display (FLCD), which comprises a cell including a layer of chiral smetic ferroelectric liquid crystal material contained between two substrates and at least one alignment layer for determining the surface alignment of the molecules in the liquid crystal material, is manufactured as follows. After selection of a suitable material for the alignment layer, the cell is filled by introducing liquid crystal material between the substrates to which the alignment layer is applied. After filling of the cell, a heat treatment is applied to the cell by raising the cell to an elevated temperature and maintaining the cell at that temperature for a predetermined period of time.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: February 1, 2000
    Assignees: Sharp Kabushiki Kaisha, The Secretary of State for Defence in Her Brittanic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland
    Inventors: John Clifford Jones, Simon David Haslam, Robert William Bannister
  • Patent number: 6007739
    Abstract: A liquid crystal compound of the present invention is represented by the following general Formula I: ##STR1## wherein R.sub.1 and R.sub.2 are independently a linear or branched alkyl group or alkoxy group having 1 to 14 carbon atoms, provided that at least one of R.sub.1 and R.sub.2 is an alkyl group; --Y-- is a group represented by the following Formula (II) or (III); and X.sub.1, X.sub.2, X.sub.3, and X.sub.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: December 28, 1999
    Assignees: Sharp Kabushiki Kaisha, Kanto Kagaku Kabushiki Kaisha
    Inventors: Akira Sakaigawa, Aya Miyazaki, Mitsuhiro Koden, Kazuhiko Tsuchiya, Kenji Suzuki
  • Patent number: 5978065
    Abstract: A liquid crystal is dropped on one end portion of a bottom substrate that is coated with a sealing material in an outer peripheral portion. After a top substrate is laid on the bottom substrate, the liquid crystal is expanded from the one end portion of the bottom substrate toward the other end portion. If necessary, an air ejecting opening is formed in the sealing material at a position located in the other end portion of the bottom substrate. The surfaces of the top and bottom substrates may be formed with grooves for accommodating an excessive part of the liquid crystal at positions inside the sealing member. As a result, no air bubbles remain in the liquid crystal even if the charging of the liquid crystal is performed at the atmospheric pressure.
    Type: Grant
    Filed: November 7, 1997
    Date of Patent: November 2, 1999
    Assignee: Sony Corporation
    Inventors: Koichi Kawasumi, Takeshi Yamasaki, Eriko Matsui, Akio Yasuda, Yuji Shiina, Tadashi Kiyomiya, Yoshihiro Yamaguchi
  • Patent number: 5963290
    Abstract: An LCD (Liquid Crystal Display) including two substrates sandwiching an LC layer therebetween, and causing a plurality of different kinds of regions to coexist in the LC layer is disclosed. An electrode formed with an aperture is provided on at least one of the substrates. A second electrode is also provided on the same substrate as the above electrode in alignment with the electrode. A voltage higher than a voltage to be applied between the electrode with the aperture and a counter electrode facing it is applied between the second electrode and the counter electrode, thereby controlling the rising direction of LC molecules. The LCD is easy to produce and achieves a great viewing angle. In addition, the LC contains a polymer in order to fix the rising directions of the LC molecules.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: October 5, 1999
    Assignee: NEC Corporation
    Inventors: Hideya Murai, Teruaki Suzuki, Masayoshi Suzuki
  • Patent number: 5923394
    Abstract: A ferroelectric liquid crystal display device is described. The device has a pair of substrates having at least an electrode film and an alignment film, and a complex made of a ferroelectric liquid crystal material and a polymer material disposed between the substrates. The complex has a network structure such that the network structure stabilizes the orientation of molecules of the ferroelectric liquid crystal material. Directions of pretilt angles of the molecules of the ferroelectric liquid crystal material located at interfaces between the substrates and the ferroelectric liquid crystal material are substantially identical. The ferroelectric liquid crystal material has a chevron layer structure, and a bending direction of the chevron layer structure is substantially identical to the directions of the pretilt angles of the molecules at the interfaces.
    Type: Grant
    Filed: June 21, 1996
    Date of Patent: July 13, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Aya Miyazaki, Mitsuhiro Koden, Paul Antony Gass
  • Patent number: 5907383
    Abstract: A method for producing a liquid crystal display device including a pair of substrates and a liquid crystal layer held between the pair of substrates, wherein the liquid crystal layer includes a polymeric region and a liquid crystal region substantially surrounded by the polymeric region, and liquid crystal molecules in the liquid crystal region are axis-symmetrically oriented, the method including the steps of: injecting a precursor mixture containing a liquid crystal material and a polymerizable material between the pair of substrates; heating the precursor mixture to a first temperature which is equivalent to or higher than a miscible temperature of the precursor mixture; cooling the precursor mixture from the first temperature to a second temperature which is lower than the miscible temperature; forming the polymeric region substantially surrounding the liquid crystal region by polymerizing the polymerizable material; and providing a tilt angle to the liquid crystal molecules in a liquid crystal droplet ph
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: May 25, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Kurihara, Yasuhiro Kume, Kenji Majima
  • Patent number: 5895107
    Abstract: In order to promote the formation of the C2 state during manufacturing of a ferroelectric liquid crystal display comprising a cell including a layer of chiral smectic ferroelectric liquid crystal material contained between two substrates. The manufacturing method includes the steps of (a) heating the liquid crystal material and (b) whilst allowing the liquid crystal material to cool from an elevated temperature, which is close to the phase transition temperature to the chiral smectic phase, allowing pressure to the liquid crystal material within the cell by means of rollers in such a manner as to produce mass flow of liquid crystal material within the cell so that the liquid crystal material preferentially adopts the C2 state on cooling to the device operating temperature. This avoids formation of both the C1 and C2 states in the manufactured display which would otherwise result in a patchy appearance, and allows faster switching at lower voltages.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: April 20, 1999
    Assignees: Sharp Kabushiki Kaisha, The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland
    Inventor: Simon David Haslam
  • Patent number: 5892497
    Abstract: A segmented ball for an electrical twisting ball color display device, the device being composed of different sets of spheroidal balls rotatably disposed in an elastomer substrate, each set being associated with a different display color. The segmented ball includes a colored interior segment surrounded on either side by transparent exterior segments, the three segments being arrayed substantially parallel to one another, with adjacent segments being adjoined to one another at substantially planar interfaces. The colored interior segment can have, for example, a transparent or opaque chromatic color, such as red, green, or blue. The ball has an anisotropy for providing an electrical dipole moment, the electrical dipole moment rendering the ball electrically responsive such that when the ball is rotatably disposed in a nonoscillating electric field while the electrical dipole moment of the ball is provided, the ball tends to rotate to an orientation in which the electrical dipole moment aligns with the field.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: April 6, 1999
    Assignee: Xerox Corporation
    Inventor: George G. Robertson
  • Patent number: 5880804
    Abstract: An improved method for achieving a defect-free and uniform liquid crystal alignment in a process for the production of a ferroelectric liquid crystal display device. A process for producing a ferroelectric liquid crystal display device containing a ferroelectric liquid crystal showing at least an N* phase and an SmC* phase and an organic polymer film or an oblique vapor-deposition film of an inorganic substance serving as an alignment layer is provided by aligning the liquid crystal by cooling the liquid crystal once to a temperature region of a phase which resides in the lower temperature region than the N* phase, and then heating it to a temperature region of an N* phase, or by aligning the liquid crystal by applying an electric field in the N* phase.
    Type: Grant
    Filed: April 9, 1996
    Date of Patent: March 9, 1999
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hidemasa Yamaguchi, Toshiaki Nonaka, Kei Li, Ayako Takeichi
  • Patent number: 5835181
    Abstract: A liquid crystal device is produced through the steps of: a) disposing a pair of substrates opposite to each other so as to form a cell between the substrates while leaving a first aperture and a second aperture for communication with an exterior and forming an effective optical modulation region between the first and second apertures, b) heating a liquid crystal material for filling the cell, and c) filling the cell with the liquid crystal material by injecting the liquid crystal material through the first aperture under a pressure difference held between the first and second apertures and, after a prescribed period, allowing the liquid crystal material to be discharged out of the second aperture. In the step c), the first aperture, the second aperture and the effective optical modulation region of the cell may preferably receive external pressures P1, P2 and P3, respectively, satisfying P1>P2 and -1 kg.f/cm.sup.2 .ltoreq.P1-P3.ltoreq.0.5 kg.f/cm.sup.2.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: November 10, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsutoshi Nakamura, Makoto Kojima, Masaki Sunaga
  • Patent number: 5812230
    Abstract: A liquid crystal display element is manufactured as follows: First, a mixture containing a ferroelectric liquid crystal (FLC) composition and a monofunctional monomer is injected into the space between opposing two electrode substrates, each of which is constituted by a substrate, an electrode, an alignment film and a polarization plate; next, the mixture is heated by irradiating it with ultraviolet light to a temperature at which the FLC composition exhibits a nematic phase or an isotropic phase so that the monomer is polymerized, and then it is cooled off. With this arrangement, isotropic micro structural elements, which locally give different threshold-value characteristics in the above-mentioned mixture, are formed into a striped structure so that a liquid crystal layer is formed. This striped structure is formed when the polymer that has been formed as a result of the polymerization is allowed to be sandwiched between smectic layers in the FLC composition during the cooling process.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: September 22, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akira Sakaigawa, Kazuyuki Kishimoto, Mitsuhiro Koden
  • Patent number: 5781266
    Abstract: A ferroelectric liquid crystal display device of the present invention includes: a pair of substrates; a ferroelectric liquid crystal layer provided between the pair of substrates; and an electrode for applying a voltage to the ferroelectric liquid crystal layer, wherein the ferroelectric liquid crystal layer has bent smectic layers, and an effective bend angle .theta.L of the bent smectic layers satisfies the relationship: .theta.Leff>.theta.L>0.degree. in a temperature range in which the ferroelectric liquid crystal display device is stored, where an effective bend angle of the smectic layers in a first state is .theta.Leff, the first state being obtained by cooling the ferroelectric liquid crystal layer from a temperature higher than a phase transition temperature of a chiral smectic C phase--a smectic A phase to a temperature not higher than a phase transition temperature of the chiral smectic C phase--the smectic A phase.
    Type: Grant
    Filed: September 26, 1994
    Date of Patent: July 14, 1998
    Assignees: Matsushita Electric Industrial Co., Ltd., Hoechst Aktiengesellschaft
    Inventors: Kenji Nakao, Hiroyuki Ohnishi, Naohide Wakita, Kazuya Nagao, Naomi Takada
  • Patent number: 5774197
    Abstract: The present invention is directed to the prevention of reversal and deterioration of a screen at right and left viewing angles and upper and lower viewing angles in an OCB-mode liquid-crystal display.It is possible to prevent deterioration of a screen by obtaining the optimum value of ?absolute value {R(V.sub.1)} of retardation before correction by phase compensation film!/wavelength (.lambda.) at a lower-side driving voltage for each color of R, G, and B and thereby, preventing an optical rotation of liquid crystal on B wavelength. Specifically, B wavelength is set to R(V.sub.1)/.lambda..ltoreq.0.85. By adjusting a cell gap of each color, display characteristics of a screen at right and left viewing angles are improved.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: June 30, 1998
    Assignee: International Business Machines Corporation
    Inventor: Hajime Nakamura
  • Patent number: 5742369
    Abstract: A method of aligning liquid crystals includes the steps of aligning chiral smectic liquid crystal sandwiched between a pair of substrates each having an electrode by applying an alternating electric field between the substrates under periodically changing temperature conditions in which a width of changes of the temperature for a single period differs in every period.
    Type: Grant
    Filed: December 22, 1994
    Date of Patent: April 21, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Mihara, Yukio Hanyu, Sunao Mori
  • Patent number: 5737115
    Abstract: A tristate light valve ball for an electrical twisting ball device composed of spheroidal balls rotatably disposed in an elastomer substrate. The ball is composed of segments arrayed substantially parallel to one another, each segment being adjacent to at least one other segment and to no more than two other segments. Adjacent segments are adjoined to one another at substantially planar interfaces. The segments include: a first, interior, nontransparent segment having a first optical modulation characteristic; a second exterior, transparent segment, adjacent to the first segment and having a second optical modulation characteristic; a third, interior, nontransparent segment having a third optical modulation characteristic; and a fourth, exterior, transparent segment adjacent to the third segment. For example, the ball can be made with a black first segment adjacent to a white third segment, surrounded on either side by clear second and fourth exterior segments.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: April 7, 1998
    Assignee: Xerox Corporation
    Inventors: Jock D. Mackinlay, Maureen C. Stone
  • Patent number: 5729319
    Abstract: A liquid crystal display device includes a pair of substrates opposed to each other, polymeric walls patterned in a predetermined pattern, and a liquid crystal layer at least a part of which is surrounded by the polymeric wall, and the polymeric wall and the liquid crystal layer are interposed between the substrates, wherein the polymeric wall has a predetermined rotatory polarization corresponding to an alignment regulating force of the substrates.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: March 17, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Ippei Inou, Yoshihiro Shirai, Makoto Shiomi
  • Patent number: 5724114
    Abstract: A liquid crystal device is constituted by (a) a pair of base plates each having an orientation control film thereon, and (b) a liquid crystal composition interposed between the base plates. The liquid crystal composition comprises a mixture including at least one liquid crystal compound which has a temperature range in which it shows chiral smectic phase and at least one optically active substance which does not have a temperature range in which it shows chiral smectic phase. The liquid crystal composition has a temperature range in which it shows cholesteric phase and is placed in chiral smectic phase which has been formed through cholesteric phase on temperature decrease. The liquid crystal composition comprises liquid crystal molecules having long axes forming a pre-tilt in the chiral smectic phase.
    Type: Grant
    Filed: May 15, 1995
    Date of Patent: March 3, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuharu Katagiri, Kazuo Yoshinaga, Shinjiro Okada, Junichiro Kanbe
  • Patent number: 5718839
    Abstract: The liquid crystalline material of the present invention comprises a compound represented by the following structural formula (1), compounds represented by the structural formulas (1) and (2), compounds represented by the structural formulas (1) and (3), or compounds represented by the structural formulas (1), (2) and (3) in an amount of 90% by weight or more of the total amount of liquid crystalline components contained therein: ##STR1## wherein R represents a linear alkyl group, C.sub.n H.sub.2n+1 in which n is 3, 4, 5, 6 or 7, A represents --CH.sub.2 CH.sub.2 -- or direct bond (--) without --CH.sub.2 CH.sub.2 --, and B represents --CH.sub.2 CH.sub.2 -- or direct bond (--) without --CH.sub.2 CH.sub.2 --. Further, under the above conditions, the components are blended so that the nematic-isotropic transition temperature of the liquid crystalline material can be 55.degree. C. to 75.degree. C.
    Type: Grant
    Filed: August 24, 1995
    Date of Patent: February 17, 1998
    Assignee: Fujitsu Limited
    Inventors: Seiji Tanuma, Takashi Sasabayashi, Takatoshi Mayama
  • Patent number: 5717515
    Abstract: A method for producing a canted electric field for an electrical twisting ball display device made up of electrically and optically anisotropic spheroidal balls rotatably disposed in a substrate. The display has an array of addressable elements, each array element including at least one spheroidal ball. According to the method, an array element is selected. A preferred direction of orientation is selected for balls of the selected array element, the direction of orientation forming an angle with a vector normal to a planar portion of the substrate surface in a vicinity of the selected array element, the angle being greater than 0 degree and less than 180 degrees.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: February 10, 1998
    Assignee: Xerox Corporation
    Inventor: Nicholas K. Sheridon
  • Patent number: 5712696
    Abstract: A method of manufacturing a liquid crystal display device including the steps of: preparing a parent substrate having an orientation structure on the surface thereof subjected to orientation treatment; interposing primary liquid crystal material between a child substrate not subjected to orientation treatment and the parent substrate, and transferring an orientation state corresponding to the orientation structure of the parent substrate to the child substrate; separating the parent substrate and the child substrate while heating the primary liquid crystal material in an isotropic phase; and forming the liquid crystal display device by using the child substrate. At least one of the two substrates of the liquid crystal display device is not required to be subjected to direct rubbing treatment. It is therefore possible to prevent device defects and performance degradation to be caused by electrostatic charges generated by rubbing.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: January 27, 1998
    Assignee: Stanley Electric, Co., Ltd.
    Inventors: Yasuo Toko, Takashi Sugiyama
  • Patent number: 5671033
    Abstract: A liquid crystal device is constituted by (a) a pair of base plates each having an orientation control film thereon, and (b) a liquid crystal composition interposed between the base plates. The liquid crystal composition comprises at least two liquid crystal compounds including at least one liquid crystal compound which has a temperature range in which it shows cholesteric phase. The liquid crystal composition has a temperature range in which it shows cholesteric phase and is placed in chiral smectic phase which has been formed through cholesteric phase on temperature decrease. The liquid crystal composition comprises liquid crystal molecules having long axes forming a pre-tilt in the chiral smectic phase.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: September 23, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuharu Katagiri, Kazuo Yoshinaga, Shinjiro Okada, Junichiro Kanbe
  • Patent number: 5612803
    Abstract: The present invention provides a liquid crystal display device including a pair of electrode substrates and a display medium sandwiched between the electrode substrates and including a polymeric wall and liquid crystal regions at least partly surrounded by the polymeric wall. In this liquid crystal display device, the polymeric wall is tightly attached to both the electrode substrates. Furthermore, the invention also provides a method for producing a liquid crystal display device including a pair of electrode substrates, at least one of which is transparent, and a display medium including a polymeric wall and liquid crystal regions at least partly surrounded by the polymeric wall and sandwiched between the electrode substrates.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: March 18, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuaki Yamada, Masahiko Kondo, Masayuki Okamoto, Shuichi Kozaki
  • Patent number: 5606440
    Abstract: A flat type display device is assembled compactly with high reliability. The flat type display device has a liquid crystal panel having electrode terminals on a peripheral portion of one face of the liquid crystal panel, a flexible wiring board having a drive IC mounted thereon for driving the liquid crystal panel, and a common wiring board having electrode terminals on one face thereof. The flexible wiring board is electrically connected to the electrode terminals of the liquid crystal panel. The common wiring board is electrically connected to the flexible wiring board so as to transmit an input signal, which has been received by the electrode terminals from external, to the drive IC.
    Type: Grant
    Filed: March 29, 1996
    Date of Patent: February 25, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hisao Kawaguchi, Shigeo Nakabu, Yasunobu Tagusa
  • Patent number: 5583671
    Abstract: A pair of transparent substrates are arranged to oppose each other and bonded to each other through a seal member. A polymer dispersed liquid crystal layer and spacers are provided between the pair of transparent substrates. A plurality of pixel electrodes respectively provided with TFTs are disposed in a matrix form on the counter surface of one substrate opposing the other substrate, and the spacers for regulating the gap between the substrates are fixed, through resin films, to remaining regions of the counter surface of one substrate obtained by excluding pixel regions corresponding to the pixel electrodes from the region inside the seal member. A black mask is formed on the remaining regions of the counter surface of the other transparent substrate, and a flat counter electrode opposing the plurality of pixel electrodes is formed on the black mask.
    Type: Grant
    Filed: November 2, 1993
    Date of Patent: December 10, 1996
    Assignee: Casio Computer Co., Ltd.
    Inventors: Tetsushi Yoshida, Jiro Takei