In Cholesteric Phase Patents (Class 349/185)
  • Publication number: 20100296038
    Abstract: The instant invention relates to liquid crystal media comprising one or more bimesogenic compounds, one or more chiral dopants and one or more additives, liquid crystal displays comprising these media, in particular displays exploiting the flexoelectric effect and to a method of improving the response time of such displays.
    Type: Application
    Filed: May 16, 2007
    Publication date: November 25, 2010
    Inventors: Louise Diane Farrand, Harry James Coles, Mikhail N. Rivnenko, Yong-il Cho
  • Patent number: 7808604
    Abstract: An in-plane switching mode liquid crystal display device includes upper and lower substrates, first and second ferroelectric liquid crystal layers, a nematic system crystal layer, and first and second electrodes. The electrodes and liquid crystal layers are located between the substrates, with the nematic liquid crystal layer between the ferroelectric liquid crystal layers. The ferroelectric liquid crystal layers have different spontaneous polarization directions. An electric field is applied to the liquid crystal layers using the electrodes. The ferroelectric liquid crystal layers react to different electric field to conduct an in-plane driving of liquid crystal molecules in the nematic liquid crystal layer.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: October 5, 2010
    Assignee: LG. Display Co., Ltd.
    Inventors: Su Seok Choi, Ku Hyun Park
  • Patent number: 7749575
    Abstract: The invention relates to a liquid crystal display utilizing a vertically aligned state of liquid crystal molecules when no voltage is applied and to a method of manufacturing the same. The invention is aimed at providing a liquid crystal display and a method of manufacturing the same in which the existing step for forming vertical alignment films can be omitted to achieve a cost reduction. The liquid crystal display includes a monofunctional monomer having a structure expressed by X-R (where X represents an acrylate group or a methacrylate group, and R represents an organic group having a steroid skeleton). A liquid crystal material is sandwiched between substrates which is then irradiated with ultraviolet rays to cure the monofunctional monomer, thereby forming a polymer film at an interface of a substrate. The monofunctional monomer has a hydrophobic skeleton such as an alkyl chain and a photoreactive group on one side of the skeleton.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: July 6, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shingo Kataoka, Hideaki Tsuda, Katsufumi Ohmuro, Jin Hirosawa, Seiji Tanuma, Yoshio Koike
  • Publication number: 20100149480
    Abstract: A display element according to the present invention is provided with a pair of substrates, at least one of which is transparent; a medium between the substrates, wherein optical anisotropy magnitude of the medium is changeable by and according to an electric field applied thereon; at least one pair of electrodes for applying, on the medium, the electric field substantially parallel to the substrates; and a shielding electrode overlapping at least a display portion of at least one of the substrates, and used for shielding the display element from static electricity.
    Type: Application
    Filed: January 26, 2010
    Publication date: June 17, 2010
    Inventors: Koichi Miyachi, Seiji Shibahara, Iichiro Inoue, Shoichi Ishihara, Akihito Jinda, Kiyoshi Ogishima
  • Publication number: 20100128215
    Abstract: A liquid crystal display (LCD) and a fabrication method thereof are provided. The LCD includes a first substrate and a second substrate opposite to the first substrate. At least two layers of cholesteric liquid crystal layers are disposed between the first and the second substrates, wherein chiral dopants with different optical activities are respectively added in the cholesteric liquid crystal layers, and the chiral dopants have the same chemical structure. The fabrication method includes providing a first substrate and a second substrate opposite to the first substrate. A plurality of chiral dopants with different optical activities and having the same chemical structure are mixed into the same liquid crystal host respectively to form at least two kinds of cholesteric liquid crystal materials. Then, the cholesteric liquid crystal materials are disposed between the first and the second substrates to form at least two layers of cholesteric liquid crystal layers.
    Type: Application
    Filed: June 23, 2009
    Publication date: May 27, 2010
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Chun-Ming Wu, Shih-Hsien Liu, Chih-Lung Chin, Kung-Lung Cheng, An-Cheng Chen
  • Patent number: 7713438
    Abstract: At least one cholesteric liquid crystal composition is mixed with at least one first nematic liquid crystal compound or composition, thereby exhibiting a TGBA phase at room temperature. The first nematic liquid crystal compound or composition preferably includes a compound having a cyano group, a halogen atom, a nitro group, a perfluoroalkoxy group or a perfluoroalkyl group at the terminal thereof. The cholesteric liquid crystal composition preferably contains a second nematic liquid crystal compound or composition and a chiral reagent.
    Type: Grant
    Filed: February 8, 2008
    Date of Patent: May 11, 2010
    Assignee: Fujifilm Corporation
    Inventor: Koji Takaku
  • Publication number: 20100110343
    Abstract: Bi-stable display systems and driving methods thereof are presented. The bi-stable display system includes a bi-stable display panel having at least one substrate, at least one electrode disposed on the substrate, and a bi-stable display medium between the at least one electrode, wherein the at least one electrode extends to pluralities of electrode pads on the at least one side of peripheral regions. A data input device for inputting display data to the bi-stable display panel includes a plurality of input terminals corresponding to the electrode pads of the bi-stable display panel. A trigger device detects relative movement between the bi-stable display panel and the data input device and generates a trigging signal to shift data address in a data shifter, thereby renewing image data in the bi-stable display panel.
    Type: Application
    Filed: February 10, 2009
    Publication date: May 6, 2010
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Chieh-Yi Huang, Chao-Kai Cheng, Yuh-Zheng Lee, Jyh-Wen Shiu, Yuan-Chang Liao
  • Publication number: 20100079720
    Abstract: A retardation film and formula thereof, and method for manufacturing the same are provided. Furthermore, the retardation film is applied to compensate TFT-LCD viewing angle. Referring to the formula of the invention, the positive A film-embedded negative C optically anisotropic coating of the retardation film can be formed by single step coating, and the retardation film with net negative C symmetry in whole is easily manufactured.
    Type: Application
    Filed: July 1, 2009
    Publication date: April 1, 2010
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Ching-Mao Wu, Ming-Tzung Wu, Kuo-Tung Huang
  • Patent number: 7652731
    Abstract: The present invention provides liquid crystal devices comprised of a composite of an internal polymer network localized on the substrate surfaces and short-pitch dual-frequency switchable cholesteric liquid crystal that operate in two different modes including in-plane switching (amplitude modulation) and out-of-plane switching (phase modulation). The invention further provides a method of making a liquid crystal device demonstrating uniform lying helical axis where the device comprises a composite of an internal spatially ordered polymer network localized by in-situ photo-polymerization at the surface of the substrate. The invention can be used for flat panel displays, as well as spatial light modulators for applications such as optical waveguides, optical beam scanners, computer-generated holograms, and adaptive optics.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: January 26, 2010
    Assignee: Kent State University
    Inventors: Liang-Chy Chien, Lei Shi, Sang Hwa Kim
  • Patent number: 7616287
    Abstract: A liquid crystal display element according to the present invention includes one or more sets of combinations of a pair of substrates, a liquid crystal layer composed of a liquid crystal composition indicating a cholesteric phase and disposed between the pair of substrates, and at least one layer of insulating thin film to insulate the liquid crystal layer from an electrode, wherein: the insulating thin film has an electrostatic capacity of not more than 10 ?F; the liquid crystal layer has a layer thickness in the range of 2 to 5 ?m; and the liquid crystal composition has a dielectric anisotropy in the range of 20 to 50. The present invention can realize at least one of lowered driving voltage, enlarged operating temperature range, decrease in electric power consumption and wide display maintaining temperature range, in a liquid crystal display element having a semi-permanent display maintaining function (memory function).
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: November 10, 2009
    Assignee: Fujitsu Limited
    Inventors: Masaki Nose, Junji Tomita
  • Patent number: 7595856
    Abstract: A cholesteric display may be formed, in some embodiments, using a single display element to produce multi-colors for display. A cholesteric material may be sandwiched between a pair of substrates, each associated with pairs of opposed electrodes that are arranged in general transversely to the optical axis of incident light. The first pair of electrodes produce one of two liquid crystal states and result in the reflection of light of a particular wavelength. Light of other wavelengths may be reflected when a second pair (or set) of opposed electrodes, arranged in general transversely, also to the optical axis of incident light, are biased appropriately. So does a third pair (or set) of electrodes. A black and white color display may be generated from a single display element by modulating the pitch length of the cholesteric material within each pairs (or sets).
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: September 29, 2009
    Assignee: Intel Corporation
    Inventors: David B. Chung, Daniel J. Lenehan
  • Patent number: 7593079
    Abstract: An optical element of the invention comprises at least three laminated circular-polarization-type-reflection polarizers (a) whose wavelength bands for selective reflection of polarized light overlap one another; a layer (b1) which is placed between at least a pair of the circular-polarization-type-reflection polarizers (a) and has a front retardation of substantially zero (in the normal direction) and a retardation of at least ?/8 with respect to incident light inclined by at least 30° relative to the normal direction; and a layer (b2) which is placed between at least another pair of the circular-polarization-type-reflection polarizers (a) and has a front retardation of substantially zero (in the normal direction) and a retardation of at most ?/2 with respect to incident light inclined by 60° relative to the normal direction.
    Type: Grant
    Filed: April 15, 2004
    Date of Patent: September 22, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Kentarou Takeda, Naoki Takahashi, Kazutaka Hara, Takahiro Fukuoka
  • Publication number: 20090225270
    Abstract: The present invention relates to a liquid-crystalline medium having high twist, to the use thereof for electro-optical purposes, and to displays containing this medium.
    Type: Application
    Filed: March 4, 2009
    Publication date: September 10, 2009
    Inventors: Akihiro KOJIMA, Makoto Murakami, Fumio Shimano, Jeong-Hee Sung
  • Patent number: 7564518
    Abstract: This invention relates to a high brightness and high contrast ratio reflective cholesteric displays employing circular polarizers. The front circular polarizer has a predetermined polarity that is opposite both to the Bragg reflection of the display and to the back reflective circular polarizer. An absorptive weak polarizer with high transmittance is adopted in the display system. In the black-and-white display mode, the white state is achieved in the cholesteric focal conic texture area; and the black state is obtained in the cholesteric planar texture area. In the full color mode, the full color state is created by the micro-color filter in the cholesteric focal conic texture area; and the black state is realized in the cholesteric planar texture area.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: July 21, 2009
    Inventor: Yao-Dong Ma
  • Patent number: 7535545
    Abstract: A transmissive liquid crystal display device includes first and second substrates spaced apart and facing each other, a cholesteric liquid crystal (CLC) color filter layer on an inner surface of the first substrate, the CLC color filter layer including first areas for displaying R, G and B and second areas between adjacent first areas, a first polarizer on an outer surface of the first substrate, a backlight unit on the first polarizer, a retardation plate on an outer surface of the second substrate, a second polarizer on the retardation plate, and a liquid crystal layer between the first and second substrates.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: May 19, 2009
    Assignee: LG Display Co., Ltd.
    Inventors: Jong-Weon Moon, Jae-Hong Hur
  • Patent number: 7511776
    Abstract: An electric field that is parallel with a TFT substrate is formed by a pair of electrodes formed on the TFT substrate. Liquid crystal molecules in a light modulating layer are caused to respond electro-optically to the electric field. The light modulating layer is constituted of a liquid crystal material, an optically active substance, and a dichroic dye. The spiral pitch p [?m] of the light modulating layer, the cell thickness d [?m], the twist angle n of liquid crystal molecules, and the interelectrode interval L [?m] are set in ranges of 1?p?15, 1?d?10, n?300°, and L<25.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: March 31, 2009
    Inventors: Takeshi Nishi, Rumo Satake, Yoshiharu Hirakata
  • Patent number: 7505094
    Abstract: A black-white liquid crystal display using a cholesteric liquid crystal material and a method for manufacturing such a liquid crystal display using polymerization/phase-separation, resulting in diffused polymeric molecules and polymeric cell walls, so as to minimize the manufacturing time, strengthen the polymeric wall and enhance the contrast ratio as well as the brightness.
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: March 17, 2009
    Assignee: Industrial Technology Research Institute
    Inventors: Yi-An Sha, Chi-Chang Liao, Hsing-Lung Wang
  • Patent number: 7499125
    Abstract: In a preparation method, a chiral or cholesteric liquid crystal, a photoreactive monomer, and a photoinitiator are disposed in a liquid crystal cell. A principal surface of the liquid crystal cell is illuminated with ultraviolet light selected to have a non-uniform ultraviolet light intensity profile in the liquid crystal cell. The illuminating cooperates with the photoinitiator to polymerize at least a portion of the photoreactive monomer near the principal surface to generate a polymer network having a density corresponding to the non-uniform ultraviolet light intensity profile. The polymer network biases the liquid crystal toward a selected helical alignment direction. In some embodiments, the illuminating includes illuminating with first and second ultraviolet light intensity profiles to produce surface and volume polymer network components.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: March 3, 2009
    Assignees: Kent State University, Lachezar Komitov
    Inventors: Lachezar Komitov, Liang-Chy Chien, Sang Hwa Kim
  • Patent number: 7473447
    Abstract: A liquid crystal display device, comprising: a liquid crystal layer comprising a cholesteric liquid crystal and a self-organizing type gelling agent, and a manufacturing method thereof, comprising: spreading a cholesteric liquid crystal containing a gelling agent in a heated state over at least one of substrates to form a liquid crystal layer, or a manufacturing method thereof, comprising: spreading a cholesteric liquid crystal that contains a gelling agent and exhibits flowability at room temperature over at least one of substrates to form a liquid crystal layer.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: January 6, 2009
    Assignee: Konica Minolta Holdings, Inc.
    Inventor: Tomoo Izumi
  • Patent number: 7382424
    Abstract: A display sheet comprising a substrate carrying layers of material; including a polymer-dispersed chiral-nematic liquid-crystal layer having a first high reflection state within the visible light spectrum and a second less-reflective state in said spectrum, said states being changeable by an electric field, which states can be maintained in the absence of an electric field; a first transparent conductor disposed over said polymer-dispersed chiral-nematic liquid-crystal layer; and a second conductor, wherein said imaging layer is substantially a monolayer of said domains comprises a mixture of at least two differently reflecting liquid crystal materials, in which the ? maximums of the two materials are separated by 100 to 250 nm.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: June 3, 2008
    Assignee: Industrial Technology Research Institute
    Inventors: Krishnan Chari, Charles M. Rankin, Jr.
  • Publication number: 20080122998
    Abstract: Cholesteric liquid crystal display devices and driving methods thereof are provided. A cholesteric liquid crystal display includes a first substrate, a second substrate and a cholesteric liquid crystal layer interposed therebetween, wherein the cholesteric liquid crystal includes at least a first displaying state and a second displaying state. A capacitance detector measures the displaying state of the cholesteric liquid crystal layer and stores the measured display state as a first output signal or second output signal in a memory device.
    Type: Application
    Filed: November 19, 2007
    Publication date: May 29, 2008
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Da-Wei Lee, Yi-An Sha, Jyh-Wen Shiu
  • Patent number: 7365906
    Abstract: A projection screen capable of sharply displaying an image even under bright environmental light with high image visibility. A projection screen has a polarized-light selective reflection layer with a cholesteric liquid crystalline structure, capable of selectively reflecting a specific polarized light component, and a substrate for supporting the reflection layer. Of the light entering the reflection layer from the viewer's side, the right-handed light in the selective reflection wave range is reflected from the reflection layer as reflected light. As a result of structural non-uniformity in the cholesteric liquid crystalline structure, the light that is selectively reflected (reflected light) is diffused.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: April 29, 2008
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7330178
    Abstract: A portable electronic device includes a display-input apparatus (108) for displaying alternate character sets, in correspondence with a selected mode of operation of the device. The display-input apparatus uses first and second cholesteric display layers (302, 304) to display the different character sets. Each cholesteric display layer displays a different character set when active. When not active, the cholesteric display layer is rendered transparent.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: February 12, 2008
    Assignee: Motorola, Inc.
    Inventors: Rudy Yorio, David S. Fredley, Douglas W. Moskowitz, James L. Tracy
  • Publication number: 20070269613
    Abstract: The present invention provides liquid crystal devices comprised of a composite of an internal polymer network localized on the substrate surfaces and short-pitch dual-frequency switchable cholesteric liquid crystal that operate in two different modes including in-plane switching (amplitude modulation) and out-of-plane switching (phase modulation). The invention further provides a method of making a liquid crystal device demonstrating uniform lying helical axis where the device comprises a composite of an internal spatially ordered polymer network localized by in-situ photo-polymerization at the surface of the substrate. The invention can be used for flat panel displays, as well as spatial light modulators for applications such as optical waveguides, optical beam scanners, computer-generated holograms, and adaptive optics.
    Type: Application
    Filed: May 16, 2006
    Publication date: November 22, 2007
    Inventors: Liang-Chy Chien, Lei Shi, Sang Hwa Kim
  • Patent number: 7298442
    Abstract: An optical body includes a) first particles comprising a first cholesteric liquid crystal material and b) a second cholesteric liquid crystal material. The first particles and the second cholesteric liquid crystal material form a structure where the first cholesteric liquid crystal material has a pitch that is different than the second cholesteric liquid crystal material. In one example, the second cholesteric liquid crystal material is in the form of second particles. In another example, the first particles are dispersed in a matrix of the second cholesteric liquid crystal material. In other examples, the optical body has more than one layer. In addition, one or more additional cholesteric liquid crystal materials can be used in the optical body. These optical bodies can be used as a reflective polarizer and can be used in a display.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: November 20, 2007
    Assignee: 3M Innovative Properties Company
    Inventors: Christopher C. Bowley, Ikuko Ebihara, Gregory Edward Gilligan, Richard John Pokorny, Marc Dudley Radcliffe, Prabhakara Satyauolu Rao, Philip Edwin Watson
  • Patent number: 7295278
    Abstract: A cholesteric display may be formed, in some embodiments, using a single display element to produce multi-colors for display. A cholesteric material may be sandwiched between a pair of substrates, each associated with a first pair of opposed electrodes that are arranged generally transversely to the optical axis of incident light. The first pair of electrodes produce one of two liquid crystal states and result in the reflection of light of a particular wavelength. Light of other wavelengths may be reflected when a second pair (or set) of opposed electrodes, arranged generally transversely to the first pair of electrodes, are biased appropriately. A color display may be generated from a single display element by modulating the pitch length of the cholesteric material.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: November 13, 2007
    Assignee: Intel Corporation
    Inventor: David B. Chung
  • Patent number: 7238397
    Abstract: A cholesteric display is provided including a bistable liquid crystalline mixture contained between a first substrate and a second substrate of a liquid crystal cell, and a polymer network orthogonally oriented with respect to the substrates, thereby defining liquid crystal domains, with a dipolar dopant dissolved in the liquid crystalline mixture. A process for producing a cholesteric display is also provided.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: July 3, 2007
    Assignee: Xerox Corporation
    Inventors: Gabriel Iftime, Peter M. Kazmaier
  • Patent number: 7206130
    Abstract: A projection screen for displaying an image by reflecting imaging light projected from a projector, including a substrate and a projected-image-receiving layer formed on the substrate. The projected-image-receiving layer has the function of selectively reflecting a specific polarized-light component and the function of diffusing the specific polarized-light component. Further, the projected-image-receiving layer includes two or more selective reflection layers having different reflection wave ranges, and, of these selective reflection layers, the selective reflection layer having a reflection wave range covering the shorter wavelength side is situated apart from the observation side as compared with the selective reflection layer having a reflection wave range covering the longer wavelength side.
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: April 17, 2007
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7193777
    Abstract: A projection screen including a polarized-light selective reflection layer having a cholesteric liquid crystalline structure that causes selective diffuse-reflection of a specific polarized-light component, and a substrate for supporting the polarized-light selective reflection layer. The polarized-light selective reflection layer includes three partial selective reflection layers, each of which contains molecules of a liquid crystal made from an organic compound, forming an organic film as a whole, and has a cholesteric liquid crystalline structure that causes selective diffuse-reflection of a specific polarized-light component. Each partial selective reflection layer of the polarized-light selective reflection layer is ordered according to wavelength of the range of light reflected. Beginning from the observation side, the order is as follows: blue (B) color wave range, green (G) color wave range, and red (R) color wave range.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: March 20, 2007
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7161737
    Abstract: A projection screen including a polarized-light selective reflection layer having a cholesteric liquid crystalline structure that causes selective diffuse-reflection of a specific polarize-light component, and a substrate for supporting the polarized-light selective reflection layer. The polarized-light selective reflection layer includes three partial selective reflection layers that are layered one over another, and each partial selective reflection layer has a cholesteric liquid crystalline structure that causes selective diffuse-reflection of a specific polarized light component. In the polarized-light selective reflection layer, three partial selective reflection layers that reflect light in the green (G) color wave range, red (R) color wave range, and blue (B) color wave range are layered in this order, the firstly-mentioned partial selective reflection layer being on the observation side.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: January 9, 2007
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7158299
    Abstract: A projection screen includes a cholesteric liquid crystalline, polarized-light selective reflection layer for selectively diffuse-reflecting a specific polarized-light component. The layer has, on its observation-side surface, a roughened part for controlling the direction of interfacial reflection of imaging light that is projected on the layer. Imaging light projected on the projection screen from a projector enters the layer and is diffuse-reflected inside this layer; this light is diffused as diffuse-reflected light, in directions included in an approximately constant range. On the other hand, part of the light projected on the projection screen from the projector is reflected, by interfacial reflection, from the inclined planes of the roughened part. The reflected light emerges from the layer in a direction different from the main direction in which the light diffuse-reflected from the layer emerges and returns to the observation side as light reflected by interfacial reflection.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: January 2, 2007
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7158297
    Abstract: A projection screen includes a polarized-light selective reflection layer having a cholesteric liquid crystalline structure, capable of selectively diffuse-reflecting a specific polarized-light component; a substrate for supporting the polarized-light selective reflection layer; and an optical member provided on the observation side of the polarized-light selective reflection layer. The optical member diffuses imaging light which the polarized-light selective reflection layer diffuse-reflects, while maintaining the state of polarization of the imaging light. The optical member diffuses right-handed circularly polarized light that is projected on the projection screen, when the light travels from the observation side to the polarized-light selective reflection layer.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: January 2, 2007
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7123410
    Abstract: A projection screen includes a polarized-light selective reflection layer having a cholesteric liquid crystalline structure, capable of selectively reflecting a specific polarized-light component; and a substrate that supports the polarized-light selective reflection layer. In the cholesteric liquid crystalline structure of the polarized-light selective reflection layer, the helical pitch on the side farther from the imaging-light-incident side is longer than that on the side closer to the imaging-light-incident side.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: October 17, 2006
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7123409
    Abstract: The present invention provides a projection screen capable of sharply displaying an image by minimizing the influence of the loss of light that occurs on a polarized-light selective reflection layer and of providing high image visibility. A projection screen includes: a polarized-light selective reflection layer that selectively reflects a specific polarized-light component; and a substrate that supports the polarized-light selective reflection layer. The polarized-light selective reflection layer includes a plurality of partial selective reflection layers that are laminated to one another, and the partial selective reflection layers have cholesteric liquid crystalline structures, owing to which they selectively reflect a specific polarized-light component.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: October 17, 2006
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Masanori Umeya
  • Patent number: 7068250
    Abstract: A method of addressing multistable nematic liquid crystal devices, in particular bistable nematic liquid crystal devices is provided. The method is a line at a time addressing scheme where one of at least two data waveforms is applied simultaneously to each of the column electrodes whilst a strobe waveform is applied to a row. The strobe waveform comprises a blanking portion sufficient to cause the liquid crystal material to blank, irrespective of which data waveform is applied, immediately followed by a discriminating portion which is such that in combination with an appropriate data waveform allows for selective latching. At least part of both the blanking portion and the discriminating portion are applied during the line address time for the particular row of interest.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: June 27, 2006
    Assignee: ZBD Displays Limited
    Inventor: John C Jones
  • Patent number: 7042536
    Abstract: A liquid crystal display element has a liquid crystal layer made of cholesteric liquid crystal and a circularly polarizing plate for circularly polarizing light. The liquid crystal layer has the following relation: d/p>1.5 where d is a thickness of the liquid crystal layer and p is a helical pitch of the cholesteric liquid crystal.
    Type: Grant
    Filed: May 3, 2002
    Date of Patent: May 9, 2006
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Naoki Hiji, Shigeru Yamamoto
  • Patent number: 7038757
    Abstract: A fabricating method of a substrate for a liquid crystal display device includes: coating a cholesteric liquid crystal material on a substrate to form a cholesteric liquid crystal layer, the substrate having a plurality of sub-pixel regions; disposing a mask having a plurality of open portions over the cholesteric liquid crystal layer; irradiating the cholesteric liquid crystal layer through the mask and curing the cholesteric liquid crystal layer, wherein each open portion is smaller than each sub-pixel region.
    Type: Grant
    Filed: September 20, 2005
    Date of Patent: May 2, 2006
    Assignee: LG.Philips LCD Co. Ltd.
    Inventors: Su-Hyun Park, Jong-Weon Moon
  • Patent number: 7038743
    Abstract: An electro-optic device includes a liquid crystal cell (10, 10?) and at least one electrode (40, 42, 40?, 42?) arranged to selectively electrically bias the liquid crystal cell (10, 10?). A chiral or cholesteric liquid crystal (30, 30?) is disposed in the liquid crystal cell (10, 10?). The liquid crystal (10, 10?) has an optic axis substantially along a selected optic axis direction in the absence of an electrical bias. A polymeric network (32, 32?, 72) is disposed at an inside surface of the liquid crystal cell (10, 10?). The polymeric network (32, 32?, 72) extends partway into the liquid crystal cell (10, 10?) leaving at least a portion of the liquid crystal cell (10, 10?) substantially free of the polymeric network (32, 32?, 72).
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: May 2, 2006
    Assignees: Kent State University, Ecsibeo AB
    Inventors: Lachezar Komitov, Liang-Chy Chien, Sang Hwa Kim
  • Patent number: 7023520
    Abstract: A method and a system for fabricating a liquid crystal film are proposed. First of all, mechanical rubbing is performed on a surface of a plastic substrate. The surface of the substrate is applied with dispersed liquid crystal material over the substrate. At least one cycle annealing treatment is performed to orientate liquid crystal molecules in a fixed direction, so that a liquid crystal solid film is formed by curing the liquid crystal molecules. In addition, a method for fabricating a brightening film using the liquid crystal solid film is also proposed. The method is applicable to a continuous process for forming a cholesteric liquid crystal film on the plastic substrate, and fabricating a reflective cholesteric liquid crystal brightening film using the cholesteric liquid crystal film, so that light transmittivity and intensity are effectively increased under the same backlight source.
    Type: Grant
    Filed: June 18, 2004
    Date of Patent: April 4, 2006
    Assignee: Charmica Photoelectronic Co., Ltd.
    Inventors: Chun-Fa Chen, Kun-Mao Yu, Charles Chang
  • Patent number: 7015998
    Abstract: A transflective LCD panel has a transmissive region and a reflective region and includes a first substrate, a second substrate opposite to the first substrate, a reflective plate formed on the second substrate and located within the reflective region, and a first liquid crystal layer and a second liquid crystal layer that are filled between the first substrate and the second substrate. The first and second liquid crystal layers correspond to the transmissive and reflective regions, respectively. The second liquid crystal layer is doped with a chiral material. When a voltage is applied, liquid crystal molecules in a middle section of the first liquid crystal layer are substantially arranged in a tilt angle ?, and the liquid crystal molecules of the second liquid crystal layer are tilted by the tilt angle and further twisted.
    Type: Grant
    Filed: June 14, 2004
    Date of Patent: March 21, 2006
    Assignee: AU Optronics Corp.
    Inventor: Ching-Huang Lin
  • Patent number: 7008675
    Abstract: An electro-optically active polymer gel material comprising a high molecular weight alignment polymer adapted to be homogeneously dispersed throughout a liquid crystal to control the alignment of the liquid crystal molecules and/or confer mechanical stability is provided. The electro-optically active polymer gel comprises a homogenous gel in which the polymer strands of the gel are provided in low concentration and are well solvated by the small molecule liquid crystal without producing unacceptable slowing of its electrooptic response. During formation of the gel, a desired orientation is locked into the gel by physical or chemical cross-linking of the polymer chains. The electro-optically active polymer is then utilized to direct the orientation in the liquid crystal gel in the “field off” state of a liquid crystal display.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: March 7, 2006
    Assignee: California Institute of Techology
    Inventors: Julia A. Kornfield, Michael D. Kempe
  • Patent number: 6999142
    Abstract: A display sheet comprising a substrate carrying layers of material; including a polymer-dispersed cholesteric liquid-crystal layer having a first high reflection state within a portion of the visible light spectrum and a second less-reflective state in said spectrum, said states being changeable by electric field between the two states which states can be maintained in the absence of an electric field; a first transparent conductor disposed over the polymer-dispersed cholesteric liquid-crystal layer; a complementary light-absorbing layer below the polymer-dispersed cholesteric liquid-crystal layer having relatively high light absorption within the spectrum of the high-reflection state of the polymer-dispersed cholesteric liquid-crystal layer and having relatively less light absorption in the spectrum complementary to that of the high reflection state of the polymer-dispersed cholesteric liquid-crystal layer; and a reflective second conductor under said complementary light-absorbing layer reflecting light rece
    Type: Grant
    Filed: June 3, 2005
    Date of Patent: February 14, 2006
    Assignee: Eastman Kodak Company
    Inventors: Stanley W. Stephenson, Terry J. Martin
  • Patent number: 6989875
    Abstract: A liquid crystal display device includes a liquid crystal cell having a cholesteric liquid crystal color filter; an integrated collimating polarizer under the liquid crystal cell, the integrated collimating polarizer having a collimating layer and a circular polarizer on the collimating layer; a backlight under the integrated collimating polarizer; a diffusing layer over the liquid crystal cell; a retardation layer over the diffusing layer; and a linear polarizer over the retardation layer.
    Type: Grant
    Filed: May 6, 2004
    Date of Patent: January 24, 2006
    Assignee: LG.Philips LCD Co., Ltd.
    Inventor: Sunghoe Yoon
  • Patent number: 6972823
    Abstract: A fabricating method of a substrate for a liquid crystal display device includes: coating a cholesteric liquid crystal material on a substrate to form a cholesteric liquid crystal layer, the substrate having a plurality of sub-pixel regions; disposing a mask having a plurality of open portions over the cholesteric liquid crystal layer; irradiating the cholesteric liquid crystal layer through the mask and curing the cholesteric liquid crystal layer, wherein each open portion is smaller than each sub-pixel region.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: December 6, 2005
    Assignee: LG. Philips LCD Co., Ltd.
    Inventors: Su-Hyun Park, Jong-Weon Moon
  • Patent number: 6950157
    Abstract: A display sheet comprising a substrate carrying layers of material; including a polymer-dispersed cholesteric liquid-crystal layer having a first high reflection state within a portion of the visible light spectrum and a second less-reflective state in said spectrum, said states being changeable by electric field between the two states which states can be maintained in the absence of an electric field; a first transparent conductor disposed over the polymer-dispersed cholesteric liquid-crystal layer; a complementary light-absorbing layer below the polymer-dispersed cholesteric liquid-crystal layer having relatively high light absorption within the spectrum of the high-reflection state of the polymer-dispersed cholesteric liquid-crystal layer and having relatively less light absorption in the spectrum complementary to that of the high reflection state of the polymer-dispersed cholesteric liquid-crystal layer; and a reflective second conductor under said complementary light-absorbing layer reflecting light rece
    Type: Grant
    Filed: June 5, 2003
    Date of Patent: September 27, 2005
    Assignee: Eastman Kodak Company
    Inventors: Stanley W. Stephenson, Terry J. Martin
  • Patent number: 6947114
    Abstract: A liquid crystal light modulation element is provided that includes a liquid crystal layer held between a pair of substrates. The liquid crystal layer includes a liquid crystal material that exhibits a cholesteric phase and has a plurality of domains. The liquid crystal layer includes regions where the helical axes of the liquid crystal molecules in a focal conic state extend in regular directions within a plane that is substantially parallel to the surface substrate.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: September 20, 2005
    Assignee: Minolta Co., Ltd.
    Inventors: Jun Yamada, Masakazu Okada, Kiyofumi Hashimoto, Mitsuyoshi Miyai
  • Patent number: 6924873
    Abstract: The objective of the present invention is to provide a liquid crystal display device for displaying colors by transmission and reflection modes and a method for producing such devices, whereby the additive color mixing can be used, the structure is simplified, the driving-voltage is lower, the contrast is higher, the response speed is higher, and the screen can be larger. This objective can be achieved by a method including the following steps: mixing 0.001 to 20 wt % of dichromatic melanotic pigment into chiral nematic liquid crystal mixed with chiral dopant; preparing a mixture of the liquid crystal and prepolymer to be polymerized into transparent polymeric solid; inserting the mixture into the space between two conductive substrates, wherein at least one of which is transparent; and irradiating ultra-violet light or neighboring short-wavelength light onto the mixture.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: August 2, 2005
    Inventor: Tadahiro Asada
  • Patent number: 6909484
    Abstract: A cholesteric display may be formed, in some embodiments, using a single display element to produce multi-colors for display. A cholesteric material may be sandwiched between a pair of substrates, each associated with pairs of opposed electrodes that are arranged in general transversely to the optical axis of incident light. The first pair of electrodes produce one of two liquid crystal states and result in the reflection of light of a particular wavelength. Light of other wavelengths may be reflected when a second pair (or set) of opposed electrodes, arranged in general transversely, also to the optical axis of incident light, are biased appropriately. So does a third pair (or set) of electrodes. A black and white color display may be generated from a single display element by modulating the pitch length of the cholesteric material within each pairs (or sets).
    Type: Grant
    Filed: October 17, 2002
    Date of Patent: June 21, 2005
    Assignee: Intel Corporation
    Inventors: David B. Chung, Daniel J. Lenehan
  • Patent number: 6897936
    Abstract: Electro-optical glazing structures (1) having total-scattering and total-transparent modes of operation which are electrically-switchable for use in dynamically controlling electromagnetic radiation flow in diverse applications.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: May 24, 2005
    Assignee: InventQjaya Sdn. Bhd
    Inventors: Le Li, Jian-Feng Li, Sadeg Faris
  • Patent number: 6885414
    Abstract: An optical router switch array includes a plurality of switchable mirror elements having holographic liquid crystal arranged in stack cells. Each of the mirror elements is isolated electrically from the other switchable mirror elements by a plurality of substrates alternative arranged between the switchable mirror elements. Holographic gratings are formed on the holographic liquid crystal by exposure to holography at predetermined incident angles. A single switchable mirror element can also be provided in cases where an array is not required. The switchable mirror elements are polarization insensitive, stable within the operational spectral region, and stable versus temperature. The invention also includes methods for manufacturing a single switchable mirror element and the optical arrray.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: April 26, 2005
    Assignee: Kent Optronics, Inc.
    Inventor: Le Li