Pleochroic Dye Patents (Class 349/165)
  • Patent number: 6346974
    Abstract: A retardation film type guest host liquid crystal display is arranged to reduce coloring in dark representation and to be energy-effective. The liquid crystal display includes a liquid crystal layer containing a given amount of dichroic dye and having a twist alignment, a reflective plate, and a phase plate located between the liquid crystal layer and the reflective plate. The phase plate has a slow axis set at 45 degrees against the alignment direction of the liquid crystal and a retardation set at a half of a phase difference between an ordinary ray before reflection by said reflective plate and an extraordinary ray after reflection.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: February 12, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Osamu Itou, Shinichi Komura
  • Publication number: 20020005930
    Abstract: A reflecting film is formed on one of the substrates, and a ¼ wavelength layer is arranged on this reflecting film. A liquid crystal layer comprises liquid crystal molecule, a polymer and dichroic dye, the polymer particles being dispersed in liquid crystal molecules. Using this configuration, a liquid crystal apparatus free from parallax is available.
    Type: Application
    Filed: January 22, 1998
    Publication date: January 17, 2002
    Inventor: TOMIO SONEHARA
  • Patent number: 6320631
    Abstract: A liquid crystal reflective display comprising cholesteric liquid crystal capable of selectively reflecting spectral rays of a specific wavelength in a visible range; and a carrier carrying said cholesteric liquid crystal, wherein at least one of said cholesteric liquid crystal and said carrier contains a coloring agent absorbing spectral rays in a wavelength range different from the selective reflection wavelength of said cholesteric liquid crystal.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: November 20, 2001
    Assignee: Minolta Co., Ltd.
    Inventors: Masakazu Okada, Takuji Hatano, Kiyofumi Hashimoto
  • Patent number: 6295101
    Abstract: In a tablet integrated type liquid crystal display apparatus, a first transparent substrate is provided on a view side. The first substrate is a plastic substrate having a thickness equal to or thinner than 0.6 mm, and a counter electrode is formed on the first substrate. A second substrate on which a driving layer composed of switching elements and pixel electrodes respectively connected to the switching elements is formed. The second substrate is a glass substrate having a thickness in a range of 0.6 mm to 1.1 mm. A guest host liquid crystal layer sandwiched by the first substrate and the second substrate such that the guest host liquid crystal is driven by a voltage applied between the counter electrode and the pixel electrode. A tablet electrode layer may be provided between the first substrate and the counter electrode. Alternatively, a tablet electrode layer may be provided on the first substrate on an opposite side of the counter electrode.
    Type: Grant
    Filed: September 9, 1999
    Date of Patent: September 25, 2001
    Assignee: NEC Corporation
    Inventors: Naoyasu Ikeda, Eishi Mizobata, Yoshihiko Hirai
  • Publication number: 20010020986
    Abstract: In a tablet integrated type liquid crystal display apparatus, a first transparent substrate is provided on a view side. The first substrate is a plastic substrate having a thickness equal to or thinner than 0.6 mm, and a counter electrode is formed on the first substrate. A second substrate on which a driving layer composed of switching elements and pixel electrodes respectively connected to the switching elements is formed. The second substrate is a glass substrate having a thickness in a range of 0.6 mm to 1.1 mm. A guest host liquid crystal layer sandwiched by the first substrate and the second substrate such that the guest host liquid crystal is driven by a voltage applied between the counter electrode and the pixel electrode. A tablet electrode layer may be provided between the first substrate and the counter electrode. Alternatively, a tablet electrode layer may be provided on the first substrate on an opposite side of the counter electrode.
    Type: Application
    Filed: May 2, 2001
    Publication date: September 13, 2001
    Inventors: Naoyasu Ikeda, Eishi Mizobata, Yoshihiko Hirai
  • Patent number: 6284418
    Abstract: Provided is an optical element comprising a biopolymer having an oriented structure and a photoresponsive compound, such as a photochromic compound, wherein at least a portion of the photoresponsive compound is incorporated within the oriented structure of the biopolymer and wherein the oriented structure is laminar with the planes of the laminar orientation being aligned perpendicular to a surface of the optical element. Preferably, the biopolymer is a liquid crystal polypeptide, such as ferroelectric liquid crystal poly(&ggr;-methyl-L-glutamate), and the photochromic compound is bacteriorhodopsin. Such optical elements may be utilized in a holographic grating, in an optical correlator system such as for pattern recognition, in a dynamic holographic recording system, and in an optical switch.
    Type: Grant
    Filed: November 16, 1999
    Date of Patent: September 4, 2001
    Assignee: Cambridge Scientific, Inc.
    Inventor: Debra J. Trantolo
  • Patent number: 6278505
    Abstract: A liquid crystal reflective display comprising cholesteric liquid crystal capable of selectively reflecting spectral rays of a specific wavelength in a visible range; and a carrier carrying said cholesteric liquid crystal, wherein at least one of said cholesteric liquid crystal and said carrier contains a coloring agent absorbing spectral rays in a wavelength range different from the selective reflection wavelength of said cholesteric liquid crystal.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: August 21, 2001
    Assignee: Minolta Co., Ltd.
    Inventors: Masakazu Okada, Takuji Hatano, Kiyofumi Hashimoto
  • Patent number: 6175398
    Abstract: The axial symmetric polarizing plate of this example includes at least one portion where light transmission easy axes are arranged with axial symmetry so that light transmission for incident light is equivalent omnidirectionally in one plane, wherein the axial symmetric polarizing plate contains at least a dichroic dye fixed in a polymer matrix formed of a polymerized liquid crystal material.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: January 16, 2001
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Nobuaki Yamada, Masayuki Okamoto, Shuichi Kozaki
  • Patent number: 6151094
    Abstract: An optical display employs a liquid crystal cell with a d.DELTA.n/.lambda. of approximately 0.2-0.8, allowing the cell's optical transmissivity to be modulated by an applied electric field through a dominant non-polarization rotation effect. For visible wavelengths, d.DELTA.n is approximately 0.1-0.4 microns, with a preferred value of about 0.25 microns. Applications include a reflective projection display in which input light is polarized at a greater than 0.degree. and less than 90.degree. angle, preferably about 20.degree., to the input LC directors of a twisted nematic cell; a reflective direct view system in which a quarter-wave plate is substituted for a polarization analyzer; and both a reflective and a transmissive guest-host system in which optical absorption by dye molecules is the dominant modulation mechanism.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: November 21, 2000
    Assignee: Hughes Electronics Corporation
    Inventor: Shin-Tson Wu
  • Patent number: 6147740
    Abstract: A liquid crystal panel has a pair of substrates disposed almost parallel to each other. On each of the substrates, an electrode and an alignment film are formed. A liquid crystal layer having a negative dielectric anisotropy is sandwiched by the substrates. In the absence of voltage applied across the electrodes, the molecules of the liquid crystal layer align almost perpendicular to the substrates. In this liquid crystal layer, a dichroic dye, preferably a blue dichroic dye, is added to absorb the yellow component of an incident light. Instead of adding the dye into the liquid crystal layer, a color compensation layer containing the dye is formed on or adjacent to at least one of the substrates. The yellow component of an incident light to the liquid crystal panel is absorbed by the color compensation layer. As a result, the liquid crystal panel and the liquid crystal display using the panel do not show yellow coloring when the panel is observed from oblique directions.
    Type: Grant
    Filed: September 10, 1997
    Date of Patent: November 14, 2000
    Assignee: Fujitsu Limited
    Inventors: Hidefumi Yoshida, Katsufumi Ohmuro
  • Patent number: 6144429
    Abstract: A liquid crystal display device comprises a reflector made of a high-reflectance material, a light scattering layer formed on the reflector, the light scattering layer containing light scattering particles introduced into a transparent resin, a first transparent electrode formed on the light scattering layer, a transparent substrate opposed to the light scattering layer with a prescribed gap interposed therebetween, a second transparent electrode formed on the transparent substrate and having a portion that is opposed to the first transparent electrode, and a layer of a guest-host type liquid crystal introduced into the gap between the light scattering layer and the transparent substrate and having a portion that is sandwiched between the first and the second transparent electrode.
    Type: Grant
    Filed: January 23, 1997
    Date of Patent: November 7, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yutaka Nakai, Masahiko Akiyama
  • Patent number: 6094252
    Abstract: A liquid crystal display device having a liquid crystal cell including: a pair of substrates at least one of which has light transparency; a chiral nematic liquid crystal layer having positive anisotropy of dielectric constant, disposed between the pair of substrates; and a voltage applying circuit for applying a voltage to the liquid crystal layer, wherein the liquid crystal layer contains a pleochroic dye, and liquid crystal molecules in the liquid crystal layer are twisted with respect to a helical axis perpendicular to surfaces of the pair of substrates, a twist angle of the liquid crystal molecules from one of the pair of substrates to the other of the pair of substrates is in a range selected from the group consisting of a range from 0.degree. to 50.degree., a range from 140.degree. to 250.degree., and a range of twist angles obtained by adding an integral multiple of n radian to the twist angles in the range from 0.degree. to 50.degree. and in the range from 140.degree. to 250.degree..
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: July 25, 2000
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yasuhisa Itoh, Naofumi Kimura
  • Patent number: 6061111
    Abstract: A reflective guest-host liquid crystal display device includes an optical reflective layer and a quarter wavelength plate (1/4 wavelength phase shifter) inside the device provides improved contrast an brightness of the display with a paper-white tone.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: May 9, 2000
    Assignee: Sony Corporation
    Inventors: Hideo Kataoka, Tetsuo Urabe, Nobuyuki Shigeno
  • Patent number: 6039893
    Abstract: A guest-host liquid crystal display device comprises a pair of substrates opposing each other with a space therebetween, a guest-host liquid crystal held in the space, the guest-host liquid crystal containing a dichroic dye mixture exhibiting a black color as a whole, and electrodes provided on the substrates for applying a voltage to the guest-host liquid crystal. The dichroic dye mixture comprises a bis-azo blue dye having a thienothiazole ring represented by the following chemical formula (1) and a tris-azo bluish purple dye having a benzothiazole ring represented by the following chemical formula (2): ##STR1## wherein R.sub.1 is a hydrogen or halogen atom, C.sub.n H.sub.2n+1, COC.sub.n H.sub.2n+1, OCOC.sub.n H.sub.2n+1, COOC.sub.n H.sub.2n+1, or CH.sub.2 COOC.sub.n H.sub.2n+1, wherein n is an integer from 1 to 8; each of R.sub.2 and R.sub.3 is a hydrogen atom or C.sub.n H.sub.2n+1 ; R.sub.3 may be ##STR2## or ##STR3## and a combination of R.sub.2 and R.sub.
    Type: Grant
    Filed: January 22, 1998
    Date of Patent: March 21, 2000
    Assignee: Sony Corporation
    Inventors: Seiichi Arakawa, Masataka Matsute, Yasutoshi Kawate
  • Patent number: 6033742
    Abstract: A liquid crystal display device comprises, a pair of substrates having an electrode on a surface thereof, and a liquid crystal layer containing a liquid crystal and a dichroic dye, wherein the dichroic dye is an anthraquinone dye exhibiting 0.08 or less of Y value represented by the following equation,Y={.SIGMA..DELTA.H tr,m/268-.SIGMA..DELTA.S tr,m}(kJK.sup.-1 kg.sup.-1)wherein .SIGMA..DELTA.H tr,m is a sum of an enthalpy change of transition from -5.degree. C. to the melting point of and an enthalpy change of melting per unit weight, and .SIGMA..DELTA.S tr,m is a sum of an entropy change of transition from -5.degree. C. to the melting point and an entropy change of melting per unit weight.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: March 7, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroki Iwanaga, Katsuyuki Naito
  • Patent number: 6016178
    Abstract: A color reflective guest-host liquid-crystal display device is provided which does not require a polarizing plate and which has a bright screen. A transparent electrode is formed on an upper substrate of a color reflective guest-host liquid-crystal display device. A reflection electrode is formed on a lower substrate, and an electro-optic element is held in the spacing between the two substrates so as to perform light modulation in response to an applied voltage. The electro-optic element has a laminated structure including a guest-host liquid-crystal layer which contains a dichroic dye and which is uniformly oriented along the transparent electrode, and a phase shifter which has a predetermined optical anisotropic axis and which is formed along the reflection electrode. The transparent electrode and the reflection electrode face each other and define a plurality of pixels. A color filter assigns incident light of a different wavelength to each pixel.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: January 18, 2000
    Assignee: Sony Corporation
    Inventors: Hideo Kataoka, Nobuyuki Shigeno, Masaki Munakata, Tetsuo Urabe
  • Patent number: 5995172
    Abstract: In a tablet integrated type liquid crystal display apparatus, a first transparent substrate is provided on a view side. The first substrate is a plastic substrate having a thickness equal to or thinner than 0.6 mm, and a counter electrode is formed on the first substrate. A second substrate on which a driving layer composed of switching elements and pixel electrodes respectively connected to the switching elements is formed. The second substrate is a glass substrate having a thickness in a range of 0.6 mm to 1.1 mm. A guest host liquid crystal layer sandwiched by the first substrate and the second substrate such that the guest host liquid crystal is driven by a voltage applied between the counter electrode and the pixel electrode. A tablet electrode layer may be provided between the first substrate and the counter electrode. Alternatively, a tablet electrode layer may be provided on the first substrate on an opposite side of the counter electrode.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: November 30, 1999
    Assignee: NEC Corporation
    Inventors: Naoyasu Ikeda, Eishi Mizobata, Yoshihiko Hirai
  • Patent number: 5995456
    Abstract: A dynamically changing, multi-color liquid crystal display for electronic watches or other design apparel items is provided. The liquid crystal displays incorporated within the watch or designer apparel item can be adapted to provide various colored images such as geometric images, animation images, customized images, designer labels, logos, etc. on colored backgrounds or alternatively provides a color changing capability that is aesthetically pleasing and fashionable. Moreover, the dynamically changing watch or other designer apparel item allows for the electronic control of the color appearance of the liquid crystal displays as well as electronic control of the liquid crystal display images, such images being generally independent of the time of day.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: November 30, 1999
    Assignee: Boit Incorporated
    Inventors: Donald R. Brewer, Michael Jarcho
  • Patent number: 5969785
    Abstract: An optical display employs a liquid crystal cell with a d.DELTA.n/.lambda. of approximately 0.2-0.8, allowing the cell's optical transmissivity to be modulated by an applied electric field through a dominant non-polarization rotation effect. For visible wavelengths, d.DELTA.n is approximately 0.1-0.4 microns, with a preferred value of about 0.25 microns. Applications include a reflective projection display in which input light is polarized at a greater than 0.degree. and less than 90.degree. angle, preferably about 20.degree., to the input LC directors of a twisted nematic cell; a reflective direct view system in which a quarter-wave plate is substituted for a polarization analyzer; and both a reflective and a transmissive guest-host system in which optical absorption by dye molecules is the dominant modulation mechanism.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: October 19, 1999
    Assignee: Hughes Electronics Corporation
    Inventor: Shin-Tson Wu
  • Patent number: 5958291
    Abstract: This liquid crystal display element is featured in that it comprises, a substrate provided on one main surface thereof with an electrode, a 3-ply GH liquid crystal layer superimposed on the substrate, each GH liquid crystal layer being different in absorption wavelength from each other and containing a host liquid crystal and a guest dichroic dye, and three transparent electrode layers, each formed on each of the GH liquid crystal layer, wherein at least one layer out of the 3-ply GH liquid crystal layer contains a fluorine-based liquid crystal and an anthraquinone-based magenta or cyan dichroic dye having at least two arylthio groups.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: September 28, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuyuki Naito, Hiroki Iwanaga
  • Patent number: 5943104
    Abstract: Light responsive, transmissivity variable eyewear utilizing two specifically configured liquid crystal cells and a method of making the cells is disclosed. The cell itself includes a pair of spaced apart transparent substrates in confronting parallel relationship to one another, transparent electrodes exposed over the outer surfaces of the substrates and connectable to a voltage control arrangement, a liquid crystal mixture contained between the substrates and tilted homeotropic alignment layers formed on the inner confronting surfaces of the substrates. The liquid crystal mixture contains a liquid crystal material with a negative dielectric anisotropy and dichroic dye molecules. All of which cooperate with one another such that the cell is highly transparent indoors, that is, out of the sunlight and is much less transparent, that is dark, in the sunlight.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: August 24, 1999
    Assignee: University Technology Corporation
    Inventors: Garret R. Moddel, David Doroski
  • Patent number: 5936688
    Abstract: A reflector includes a substrate, a plurality of convex/concave portions formed on the substrate, and a thin reflective film formed over the convex/concave portions. When light is incident upon the reflector from a certain direction, an intensity of reflected light in a viewing angle range of about -45.degree. to +45.degree. with respect to a regular reflection direction of the incident light is about 60% or more of an intensity of light which is incident upon a standard white plate from a direction inclined by about 30.degree. from a direction normal to the plate and is reflected to the direction normal to the plate.
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: August 10, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kazuhiko Tsuda, Masako Nakamura, Akiyoshi Fujii, Mariko Ban, Yasuhisa Itoh, Kozo Nakamura, Naofumi Kimura
  • Patent number: 5933203
    Abstract: Driver apparatus and methods of driving at least a portion of a cholesteric liquid crystal ("CLC") panel to a state having a given reflectivity. One of the methods includes the steps of: (1) initially driving the portion to a nematic phase, (2) subsequently driving the portion to a cholesteric phase focal-conic state, the cholesteric phase focal-conic state providing a known reference state for subsequent driving of the portion and (3) thereafter driving the portion to the state having the given reflectivity.
    Type: Grant
    Filed: January 8, 1997
    Date of Patent: August 3, 1999
    Assignee: Advanced Display Systems, Inc.
    Inventors: Bao-Gang Wu, Jianmi Gao, Meng Zhao
  • Patent number: 5926242
    Abstract: A reflective guest-host liquid-crystal display includes: a pair of upper and lower substrates joined together with a predetermined space therebetween; and a guest-host liquid-crystal layer which is held within the space and contains a dichroic dye. The upper substrate is provided with at least a counter electrode. At least thin-film transistors (TFTs), a reflective layer, a .lambda./4 phase shifter (quarter-wavelength plate), and pixel electrodes are formed on the lower substrate. The .lambda./4 phase shifter is formed above the TFTs and the reflective layer, and has contact holes connecting to the drain electrodes of the TFTs. The pixel electrodes are patterned on the .lambda./4 phase shifter and connected to the corresponding drain electrodes of the TFTs through the corresponding contact holes.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: July 20, 1999
    Assignee: Sony Corporation
    Inventors: Hideo Kataoka, Ying Bao Yang, Nobuyuki Shigeno, Tetsuo Urabe, Masaki Munakata
  • Patent number: 5875014
    Abstract: An optically anisotropic film comprising a mixture of a polymer, a dye having an absorption peak not in a visible region but in an ultraviolet region, and occasionally a liquid crystal polymer, wherein the retardation of the optically anisotropic film is between 50 nm and 3000 nm, and the dye has an aspect ratio of 1.5 or more, or the dye shows a dichroism. The optically anisotropic film has a high wavelength dispersion of the retardation, and a liquid crystal display apparatus achieves an excellent black-and-white display by using the optically anisotropic film.
    Type: Grant
    Filed: May 9, 1997
    Date of Patent: February 23, 1999
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Masato Kuwabara, Toshihiro Ohnishi
  • Patent number: 5856859
    Abstract: A reflective liquid crystal display device includes a pair of substrates and a liquid crystal layer interposed therebetween. The liquid crystal layer includes a liquid crystal material and a dichroic dye contained therein, and long axis of liquid crystal molecules near the substrate is substantially parallel to the substrate. A plurality of parameters of the reflective liquid crystal display device are set so that a product K.sub.M cd of a value K.sub.M, a dye concentration c and a thickness d of the liquid crystal layer satisfies the following relationship:3.0S.sup.2 -7.3S+5.7.ltoreq.K.sub.M cd.ltoreq.14.7S.sup.2 -15.1S+6.15wherein, the value K.sub.M is a value defined by absorption coefficients for linearly-polarized light substantially parallel to and perpendicular to the liquid crystal molecules, and an order parameter S of the liquid crystal layer.
    Type: Grant
    Filed: July 2, 1997
    Date of Patent: January 5, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yasuhisa Itoh, Naofumi Kimura
  • Patent number: 5847791
    Abstract: A reflective color liquid crystal comprising a guest-host liquid crystal display, a color filter and a reflector. The reflector is a simple mirror-like reflection surface. The color filter is manufactured with a pigment dispersion method. The particle size of the pigment is reduced to provide strong light forward scattering and weak light back scattering. The color filter provides light colors for the display as well as light scattering to increase the viewing angle for the display.
    Type: Grant
    Filed: April 1, 1997
    Date of Patent: December 8, 1998
    Assignee: Industrial Technology Research Institute
    Inventor: Chia Wei Hao
  • Patent number: 5798809
    Abstract: A liquid crystal display panel including a guest-host type liquid crystal layer and a reflecting plate. A polarized light rotating member is arranged between the liquid crystal layer and the reflecting plate for rotating a vibrating plane of an incident polarized light to reduce a dispersion of states of polarization of light regarding wavelength. The polarized light rotating member preferably comprises first and second superimposed linear phase plates. The .DELTA.nd of the first linear phase plates located on the side of the liquid crystal layer from the second phase plate is approximately .lambda..sub.0 /2 and the .alpha.nd of the second linear phase plate is approximately .lambda..sub.0 /4.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: August 25, 1998
    Assignee: Fujitsu Limited
    Inventors: Kimiaki Nakamura, Yoshio Koike
  • Patent number: 5784136
    Abstract: A liquid crystal layer composing a liquid crystal display apparatus is formed by being laminated with a plurality of single particle layers of liquid crystal micro-capsules having a uniform size and being arranged in a two-dimensional crystal array, the liquid crystal micro-capsule being formed by cladding a liquid crystal droplet with a medium having a constant thickness. The liquid crystal micro-capsule is formed by being cladded with a medium composed of gelatine and gum arabic. Further, the single particle layer has a filling medium for making the surface flat and filling the gaps among the liquid crystal micro-capsules. The filling medium is composed of gelatine and gum arabic.
    Type: Grant
    Filed: September 9, 1996
    Date of Patent: July 21, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Ando, Shinichi Komura, Makoto Tsumura, Yoshiharu Nagae
  • Patent number: 5742368
    Abstract: A reflection liquid crystal display device which comprises a display substrate and a back substrate each having an electrode, and disposed in spaced opposition to each other; a liquid crystal layer which is provided between the display substrate and the back substrate, and composed of nematic liquid crystal to which dichromatic dye is added; a reflector plate provided on the back substrate; and a quarter-wave plate provided between the reflector plate and the liquid crystal layer. In the liquid crystal display device, twist pitch P of the liquid crystal and the distance d between the substrates satisfy the following expression:1/4.ltoreq.d/P<3/4.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: April 21, 1998
    Assignee: Alps Electric co., Ltd.
    Inventor: GuoPing Chen
  • Patent number: 5731858
    Abstract: A reflecting type liquid crystal display device having, a first substrate provided on one main surface thereof with a first electrode comprising a plurality of pixel electrodes arrayed in a matrix form and a wiring interposed between these pixel electrodes, the first substrate being disposed on an observation side, a second substrate provided on one main surface thereof with a second electrode and disposed to face the first substrate in such a manner that the surface bearing the second electrode faces to the surface bearing the first electrode, a liquid crystal composition layer interposed between the first substrate and the second substrate, and a white reflecting layer formed on a region of the surface of the first substrate where the first electrode is not formed.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: March 24, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuzo Hisatake, Ryoichi Watanabe, Makiko Sato, Hitoshi Hatoh, Akio Murayama
  • Patent number: 5729307
    Abstract: An antiferroelectric liquid crystal device of the present invention includes at least a first antiferroelectric liquid crystal cell and a second antiferroelectric liquid crystal cell, wherein the first and second antiferroelectric liquid crystal cells respectively have an antiferroelectric liquid crystal material interposed between a pair of electrode substrates each having an electrode film and an alignment layer, and the first and second antiferroelectric liquid crystal cells are disposed so that a normal to an antiferroelectric liquid crystal layer of the first antiferroelectric liquid crystal cell is orthogonal to a normal to an antiferroelectric liquid crystal layer of the second antiferroelectric liquid crystal cell.
    Type: Grant
    Filed: October 25, 1995
    Date of Patent: March 17, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Mitsuhiro Koden, Kazuhiko Tamai
  • Patent number: 5726729
    Abstract: A liquid crystal display device comprising a first substrate having a first electrode and a homeotropic aligning film formed thereon, a second substrate having a second electrode and a homogeneous aligning film formed thereon, and a chiral nematic liquid crystal sealed between the first and second substrates. One % by weight of a dichroic dye is added to the chiral nematic liquid crystal. The liquid crystal molecules of this liquid crystal display device has a twist angle .theta. of 0.5.pi. radians or greater and smaller than (5/3).pi. radians. The cell gap d of the liquid crystal display device and the natural pitch p of the nematic liquid crystal are selected in such a way that d/p satisfies an inequality (9):(.theta./2.pi.)-(1/4)<d/p<(.theta./2.pi.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: March 10, 1998
    Assignee: Casio Computer Co., Ltd.
    Inventor: Jiro Takei
  • Patent number: 5699135
    Abstract: A reflecting type liquid crystal display device having, a first substrate provided on one main surface thereof with a first electrode comprising a plurality of pixel electrodes arrayed in a matrix form and a wiring interposed between these pixel electrodes, the first substrate being disposed on an observation side, a second substrate provided on one main surface thereof with a second electrode and disposed to face the first substrate in such a manner that the surface bearing the second electrode faces to the surface bearing the first electrode, a liquid crystal composition layer interposed between the first substrate and the second substrate, and a white reflecting layer formed on a region of the surface of the first substrate where the first electrode is not formed.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: December 16, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuzo Hisatake, Ryoichi Watanabe, Makiko Sato, Hitoshi Hatoh, Akio Murayama
  • Patent number: 5636185
    Abstract: A dynamically changing, multi-color liquid crystal display for electronic watches or other design apparel items is provided. The liquid crystal displays incorporated within the watch or designer apparel item can be adapted to provide various colored images such as geometric images, animation images, customized images, designer labels, logos, etc. on colored backgrounds or alternatively provides a color changing capability that is aesthetically pleasing and fashionable. Moreover, the dynamically changing watch or other designer apparel item allows for the electronic control of the color appearance of the liquid crystal displays as well as electronic control of the liquid crystal display images, such images being generally independent of the time of day.
    Type: Grant
    Filed: March 10, 1995
    Date of Patent: June 3, 1997
    Assignee: Boit Incorporated
    Inventors: Donald R. Brewer, Michael Jarcho
  • Patent number: 5615032
    Abstract: An electrically activated infrared filter utilizes a mixture of infrared absorbing dyes in liquid crystal which normally presents a substantial cross section of dye to absorb the infrared component of impinging light. Polarizing light to be parallel to the direction of liquid crystal alignment enhances the absorption of infrared components. In an alternative embodiment, a chiral additive to the liquid crystal solution increases the dye cross section density which, by absorption, attenuates a higher proportion of the infrared wavelengths. A predetermined voltage differential across the cell aligns the liquid crystal and dye molecules to the voltage gradient, presenting a substantially non-absorptive path to the infrared components of impinging light.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: March 25, 1997
    Assignee: Kaiser Aerospace and Electronics Corporation
    Inventors: Michael H. Kalmanash, Vijay M. Sethna
  • Patent number: 5589965
    Abstract: A wide viewing-angle twisted nematic liquid crystal display is provided. The wide viewing-angle is achieved by the application of properly aligned retardation films in between a 90.degree. twisted nematic liquid crystal cell and one of two polarizers, as well by doping the liquid crystal with an appropriate amount of dichroic dye molecules. These two additional elements not only increase the viewing-angle but also improve the chromaticity of the display. The retardation films convert the polarization state of the transmitted light of the liquid crystal cell to a more linearly polarized light in order to achieve higher contrast ratio at -45.degree. and +45.degree. scanning direction relative to the rub direction of the back substrate of the cell. The dichroic dye molecules operate on the absorption principle and further improve the contrast ratio along a 90.degree. scanning direction. By combining both elements in a liquid crystal display, a much wider viewing-angle is achieved.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: December 31, 1996
    Assignee: Litton Systems (Canada) Limited
    Inventors: Birendra Bahadur, Kam H. Wan