Cholesteric Reflector Patents (Class 349/115)
  • 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: 6903788
    Abstract: An optical film having excellent light utilization efficiency and high brightness, and a liquid crystal display using the optical film. The optical film is formed by laminating integrally a brightness enhancement film (A) that separates natural light into transmitted light and reflected light and a collimating film (B) having an uneven portion on a surface thereof. Since an air interface is eliminated by the integral lamination of the brightness enhancement film and the collimating film, stray light is reduced, and the brightness enhancement film has an improved efficiency in reflecting and polarizing light; thereby, enhancing the brightness.
    Type: Grant
    Filed: July 3, 2002
    Date of Patent: June 7, 2005
    Assignee: Nitto Denko Corporation
    Inventors: Miki Shiraogawa, Hironori Motomura, Ikuo Kawamoto
  • Patent number: 6900864
    Abstract: In an electro-optical device, such as a transflective liquid crystal device, color transmissive display having normal color tones is performed, and in addition, bright, color reflection display is also performed. The electro-optical device in accordance with the invention includes an electro-optical material provided between a first substrate and a second substrate, and display electrodes provided above the first substrate so as to be opposed to the second substrate. The electro-optical device further includes a first color filter having a selective-reflection region in each pixel that selectively reflects light in a predetermined wavelength range, and a light transmission region in each pixel that transmits light outside of the predetermined wavelength range; a light-shielding film provided so as to be opposed to the selective-reflection regions; and a second color filter having a selective-transmission region in each pixel that selectively transmits light in the predetermined wavelength range.
    Type: Grant
    Filed: June 6, 2002
    Date of Patent: May 31, 2005
    Assignee: Seiko Epson Corporation
    Inventor: Shoichi Iino
  • Patent number: 6897915
    Abstract: A liquid crystal device comprises a first and second cell wall structure; at least one liquid crystal material disposed within a space between the first and second cell wall structures; and polymer micro-structures, wherein the micro-structures are formed by polymerizing a prepolymer, and wherein said micro-structures have a shape and spatial location determined by said liquid crystal material. Permanent polymer micro-structures are formed from a liquid crystal with a non-uniform spatially modulated director field. The polymer structures have the shape and spatial location dictated by the non-uniform director field of the liquid crystal. The micro-structures are a backbone that restores the liquid crystal director field that existed during the polymerization process even when other factors, such as electric field, temperature, or surface anchoring, do not favor this restoration.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: May 24, 2005
    Assignee: Kent State University
    Inventors: Oleg D. Lavrentovich, Dmitry Voloschenko, Sergij Shiyanovskii
  • Patent number: 6891585
    Abstract: Disclosed herein is a process of producing a circularly-polarized-light-extracting optical element adapted to effectively prevent the appearance of bright and dark stripes on the screen of a display to avoid lowering of the displaying quality of the display. The circularly-polarized-light-extracting optical element includes a glass substrate 11, an alignment layer 12 laminated to the glass substrate 11, and a cholesteric layer 13 formed on the alignment layer 12, in which molecules are aligned in the sate of planar alignment due to the alignment-regulating action of the surface of the alignment layer 12. The cholesteric layer 13 has a first surface 13a on its glass substrate 11 side, and a second surface 13b opposite to the first surface 13a. Director directions of molecules on the first surface 13a of the cholesteric layer 13 are aligned in substantially one direction owing to the alignment-regulating action of the surface of the alignment layer 12.
    Type: Grant
    Filed: April 4, 2002
    Date of Patent: May 10, 2005
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Keiji Kashima
  • Patent number: 6888607
    Abstract: Rewritable signs (100, 1300) that include bistable cholesteric liquid crystal layers (102, 1402, 1404, 1406) are provided. According to one embodiment a rewritable sign (100) is devoid of circuitry for establishing electric fields in localize regions for writing information to the rewritable sign (100), and is consequently inexpensive. In the latter embodiment, a separate information writer (400) that includes an array of pixel electrodes (404) that is driven by an active matrix (602) is used to write information on the rewritable sign. According to another embodiment a rewritable sign (1300) includes three cholesteric liquid layers (1402, 1404, 1406) each of which reflects a different primary color. The three cholesteric liquid crystal layers (1402, 1404, 1406) are interleaved with sets of conductive lines (1316, 1320, 1322, 1324) that are used to apply signals to the cholesteric liquid crystal layers (1402, 1404, 1406) for the purpose of writing information.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: May 3, 2005
    Assignee: Motorola, Inc.
    Inventors: Bobby Dean Landreth, Steven D. Pratt, Robert W. Pennisi, Ronald J. Kelley, Sivakumar Muthuswamy, David S. Fredley
  • Patent number: 6888612
    Abstract: Disclosed are liquid crystal (LC) phase-retarders and linear polarizers and methods and apparatus for making the same. The liquid crystal phase-retarder is realized by a liquid crystal film structure having one or more phase retardation regions formed therein. Each phase retardation region has an optical axis specified by the direction and depth of orientation of liquid crystal molecules along the surface of the liquid crystal film structure. The liquid crystal linear polarizer is realized by a liquid crystal film structure having a chiral phase region within which liquid crystal molecules are cholesterically ordered. One or more nematic phase regions are formed along the surface of the liquid crystal film structure within which liquid crystal molecules are oriented along a direction and to a surface depth sufficient to realize one or more phase retardation regions therein having optical axes along the direction of liquid crystal molecule orientation.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: May 3, 2005
    Assignee: Vrex, Inc.
    Inventor: Sadeg M. Faris
  • Patent number: 6879362
    Abstract: The present invention provides a cholesteric liquid crystal color filter including partition walls that are formed at pixel boundaries, produced by: forming a liquid crystal layer comprising a cholesteric liquid crystal composition including at least a liquid crystal compound, a photoreactive chiral agent and a polymerization initiator; and irradiating the liquid crystal layer with UV light having wavelengths to which the polymerization initiator is photosensitive through a photomask to form the partition walls at areas corresponding to the pixel boundaries while the liquid crystal layer is in an isotropic liquid state or in a cholesteric state not exhibiting selective reflection of light in the visible range. The invention also provides a process for producing a cholesteric liquid crystal color filter including openings that are formed at positions corresponding to at least contact holes and/or electrode lead-out portions.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: April 12, 2005
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Kouya Kawabata
  • Patent number: 6876429
    Abstract: Provided herein is a method for fabricating an array. A plurality of insulating media are formed having a plurality of wavelength and polarizing elements embedded therein at an angle relative to the surfaces of the media, such that the spacing between elements halves for each different medium. A phase shifter arrangement is also formed such that a portion of conductive material is disposed on a surface of the insulating media in registry with every other element in each of the media, and other portion of conductive material disposed on another surface overlapping said elements. A phase shifting material is disposed over at least said every other element. The media are stacked such that the topmost insulating medium has two elements, and each succeeding medium has twice as many elements as a preceding medium.
    Type: Grant
    Filed: January 16, 2004
    Date of Patent: April 5, 2005
    Assignee: Reveo, Inc.
    Inventor: Sadeg M. Faris
  • Patent number: 6873381
    Abstract: A light controlling film is described comprising a polymerized polymer network of a crosslinked high molecular weight polymeric material and a low molecular weight cholesteric liquid crystal (CLC) material, wherein the high molecular weight and the low molecular weight form a material having cholesteric liquid crystal (CLC) order such that the film is a reflective circular polarizer whose bandwidth is controllable by an electric field impressed in the film.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: March 29, 2005
    Assignee: Reveo, Inc.
    Inventors: Bunsen Fan, Jian-feng Li, Le Li, Sadeg Faris
  • Patent number: 6870586
    Abstract: The invention provides a liquid crystal display device which has excellent visibility and which provides a bright display by increasing the amount of light reflected in a direction of a line of sight of a user in a reflective or a transflective liquid crystal display device. The invention also, provides an electronic device including the same. The invention provides a liquid crystal display device including opposing upper and lower substrates liquid crystal sandwiched between the upper and lower substrates, and an upper polarizer (upper polarization layer) and a lower reflective polarization layer disposed above and below the liquid crystal, respectively. The lower reflective polarization layer is formed by stacking prism-shaped dielectric interference films having two types of wedge-shaped cross-section inclined surfaces formed continuously at regular intervals. Angles formed between each of the two types of inclined surfaces and the lower substrate are different.
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: March 22, 2005
    Assignee: Seiko Epson Corporation
    Inventor: Chiyoaki Iijima
  • Patent number: 6859245
    Abstract: A reflector for reflecting a broad bandwidth of electromagnetic (EM) radiation, comprising a sheet comprising a large plurality of pairs of layers of transparent polymer material parallel to a surface of the sheet, each pair of layers having a difference in the index of refraction between the materials in each layer of the pair, the total thickness of each pair of layers in the large plurality of layers varying substantially continuously and non linearly across the thickness of the sheet, is disclosed.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: February 22, 2005
    Assignee: Reveo, Inc.
    Inventors: Sadeg M. Faris, Le Li
  • Patent number: 6842210
    Abstract: A liquid crystal display device which has a liquid crystal composition between a first substrate and a flexible second substrate. The liquid crystal composition is filled between the substrates by being dispensed on the first substrate and spread uniformly while the second substrate is being pressed against the first substrate by a roller, and the liquid crystal composition is sealed by sealing resin provided on the sides of the substrates. The gap between the substrates is maintained by spherical spacers and/or a resin structure.
    Type: Grant
    Filed: February 21, 2003
    Date of Patent: January 11, 2005
    Assignee: Minolta Co., Ltd.
    Inventors: Kiyofumi Hashimoto, Masakazu Okada, Kenji Nishiguchi, Tatsuo Taniguchi
  • Patent number: 6842209
    Abstract: A liquid crystal display device comprising a first polarizing sheet (16a), a color filter layer (6) formed on glass sheet (18), a second polarizing sheet (16b), three-layered HPDLC (17) formed below the liquid crystal layer (1) and acting as a reflective structural layer having a reflectivity changed electrically, and a backlight unit as the lowermost layer. Each layer of the three-layered HPDLC (17) is composed of a liquid crystal droplet layer polymer layer and reflects blue, green, red by Bragg reflection. When voltage is applied to the three-layered HPDLC (17), the reflectivity of liquid crystal droplet layer of each layer change, so that the HPDLC can be made transparent by equalizing the reflectivities of the liquid crystal liquid droplet layer to those of polymer layers.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: January 11, 2005
    Assignee: NEC Corporation
    Inventors: Ken Sumiyoshi, Hiroshi Hayama
  • Patent number: 6836307
    Abstract: A cholesteric liquid crystal coating film 13′ is formed on an alignment layer 12 provided on a glass substrate 11 (FIG. 1(a)), and is subjected to a thermal alignment process at a temperature equal to or higher than the liquid crystalline phase transition temperature of a chiral nematic liquid crystal that constitutes the coating film (FIG. 1(b)). Active rays capable of activating optically active groups in the chiral nematic liquid crystal are applied to the cholesteric liquid crystal coating film 13′ to deactivate the optically active groups, thereby forming a cholesteric layer 13 having color-indicating regions with the desired areas and indication colors that have been created according to the active-rays-applied area and to the amount of active rays applied to the area (FIG. 1(c)). Thereafter, this cholesteric layer 13 is subjected to a thermal alignment process at a temperature lower than the liquid crystalline phase transition temperature of the chiral nematic liquid crystal (FIG. 1(d)).
    Type: Grant
    Filed: July 1, 2002
    Date of Patent: December 28, 2004
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Norihito Itoh
  • Patent number: 6836313
    Abstract: The present invention provides an optical element capable of keeping the accuracy even in the case of use in an optical device such as an image display apparatus, without the risk of fluctuation of the optical characteristics even in the case a load is applied at the time of being assembled in the optical device. In order to achieve the object, an optical element comprising a supporting member, and an optical functional layer of a polymerizable liquid crystal material hardened on the supporting member with a predetermined liquid crystal regularity, wherein the optical functional layer has a 20 or more Vickers hardness value, is provided.
    Type: Grant
    Filed: December 2, 2002
    Date of Patent: December 28, 2004
    Assignee: Dai Nippon Printing Co., Ltd.
    Inventor: Koji Ishizaki
  • Patent number: 6833889
    Abstract: A reflective cholesteric liquid crystal (CLC) display device has a reflection layer in or on a cholesteric liquid crystal color filter to increase a luminance and a contrast ratio of a liquid crystal display device. A reflective cholesteric liquid crystal display device includes a first substrate, an absorption layer on the first substrate, a cholesteric liquid crystal color filter on the absorption layer, a reflection layer on the absorption layer, the reflection layer reflecting light in a whole range of wavelengths, a first electrode on the cholesteric liquid crystal (CLC) color filter, a second substrate spaced apart from and over the first substrate, a second electrode beneath the second substrate, a retardation layer on the second substrate, a polarizer on the retardation layer and a liquid crystal layer between the first electrode and the second electrode.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: December 21, 2004
    Assignee: G. Philips LCD Co., Ltd.
    Inventors: Jong-Weon Moon, Sung-Hoe Yoon
  • Patent number: 6833892
    Abstract: The invention provides a liquid crystal display device that is excellent in presenting a bright and visible display in a wide viewing angle. A transflective layer formed of cholesteric liquid crystal layers, each having a plurality of unflat portions, and reflecting at least a portion of elliptically polarized light having a predetermined rotation direction, is arranged on the inner surface of a lower substrate. An upper-substrate side elliptically-polarized-light input device is arranged to allow elliptically polarized light to enter a liquid crystal layer from an upper substrate. The liquid crystal layer reverses the component of the elliptically polarized light which is incident during one of electric field applied state and electric field non-applied state, while not changing the component of the elliptically polarized light during the other of the electric field applied state and the electric field non-applied state.
    Type: Grant
    Filed: October 24, 2002
    Date of Patent: December 21, 2004
    Assignee: Seiko Epson Corporation
    Inventor: Kimitaka Kamijo
  • Patent number: 6833891
    Abstract: A reflective liquid crystal display (LCD) including a cholesteric liquid crystal polarizing device and a liquid crystal cell superimposed with one another. In various embodiments, the reflective LCD may be a normally white mode or normally black mode device. In another variation, the liquid crystal cell may include a 90° twisted nematic liquid crystal.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: December 21, 2004
    Assignee: Reveo, Inc.
    Inventors: Yingqiu Jiang, Aharon Hochbaum
  • Patent number: 6833885
    Abstract: A liquid crystal display apparatus includes a first liquid crystal layer having first liquid crystal exhibiting a cholesteric phase at a room temperature, and being tuned to selectively reflect light of a wavelength &lgr;1 within a visible wavelength range; and a second liquid crystal layer disposed on the first liquid crystal layer, having second liquid crystal exhibiting a cholesteric phase at the room temperature, and being tuned to selectively reflect light of a wavelength &lgr;2 within the visible wavelength range, wherein a difference between the selective reflection wavelengths &lgr;1 and &lgr;2 is in a range from 100 nm to 150 nm.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: December 21, 2004
    Assignee: Minolta Co., Ltd.
    Inventors: Akihito Hisamitsu, Noboru Ueda, Nobuyuki Kobayashi, Hideaki Ueda
  • Patent number: 6831720
    Abstract: A color liquid crystal display using reflective color filters using layers of cholesteric liquid crystals is disclosed. The reflective color filters have two different center wavelengths and bandwidths per layer and are stacked in two layers to provide colored light for displays. With various numbers of layers in the stack, different polarization levels are provided. The pixels in the display of the invention are arranged such that multiple adjacent sub-pixels in a layer with the same color makes the color filters easier to manufacture.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: December 14, 2004
    Assignee: Reveo, Inc.
    Inventors: Yingqiu Jiang, Le Li, Aharon Hochbaum, Sameer Vartak, Hristina Galabova, Richard Wiley, Sadeg M. Faris
  • Publication number: 20040239849
    Abstract: A liquid crystal display with mirror face function. A light deflecting plate is disposed on one face of the liquid crystal display module opposite to the backlight element. A brightness enhancement film is disposed between the liquid crystal display module and the light deflecting plate. The direction of the light penetration axis of the brightness enhancement film is identical to the direction of the light penetration axis of the liquid crystal display module, whereby external light is reflected by the brightness enhancement film to achieve a mirror face effect. The light emitted by the liquid crystal display module can easily pass through the brightness enhancement film so that the light penetrability of the liquid crystal display module is enhanced.
    Type: Application
    Filed: June 2, 2003
    Publication date: December 2, 2004
    Inventor: Po Hsien Wang
  • Patent number: 6825903
    Abstract: A liquid crystal display element comprises a polarization plates, phase difference plates, a liquid crystal layer, and selectively reflective layers for reflecting part or whole of circularly polarized light in a specific direction. The products of the respective thicknesses of the polarization plate, phase difference plate, liquid crystal layer, and selectively reflective layer and the difference between an average refractive index in a direction perpendicular to each display plane and an average refractive index in a direction parallel to the display plane are set so that the absolute value of their sum total is 50 nm or less. Each selectively reflective layer is formed of a layer having positive refractive index anisotropy and a layer having negative refractive index anisotropy.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: November 30, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshiya Ohtake, Yuzo Hisatake, Atsuko Oono
  • Patent number: 6822712
    Abstract: A reflection liquid crystal display is such that a transparent substrate is opposed to the first substrate with a liquid crystal layer placed therebetween, and the transparent substrate is disposed forward to the first substrate in the light-incident direction. A quarter-wavelength plate is disposed in the transparent substrate, and a polarization plate is disposed on the surface at the forward side thereof in the light-incident direction. And, a reflection layer besides acting as a color filter consisting of a cholesteric liquid crystal is disposed inside liquid crystal cells of the first substrate. In the case of a wide field-of-view angle, a scattering film is disposed forward to the polarization plate in the light-incident direction.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: November 23, 2004
    Assignees: NEC Corporation, NEC LCD Technologies, Ltd.
    Inventors: Masayoshi Suzuki, Teruaki Suzuki, Toshiya Ishii
  • Patent number: 6822710
    Abstract: A backlight device for a liquid crystal display device includes a light source providing light; a light waveguide plate 40 guiding light from the light source, having an emitting surface, a front surface and a bottom surface, the emitting surface adjacent to the light source; a reflector arranged under the bottom surface of the light wave guide plate, reflecting light; and at least one cholesteric liquid crystal (CLC) film arranged over the front surface of the light wave guide plate, collimating light.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: November 23, 2004
    Assignee: LG. Philips LCD Co., Ltd.
    Inventors: Hyeon-ho Son, Jong-weon Moon
  • Patent number: 6822711
    Abstract: A liquid crystal display apparatus includes a liquid crystal element including a front substrate positioned on the side of an observer and having a first electrode mounted to one surface, a rear substrate having a second electrode arranged to face said first electrode, and a liquid crystal layer interposed between these substrates, said liquid crystal layer controlling the polarized state of the transmitted light in accordance with the electric field applied between the first and the second electrodes. A first reflection polarizing plate is arranged on the front side of the liquid crystal element and reflects the light of one of the two polarized components of the incident light. Two polarized components are perpendicular to each other, and transmit the light of the other polarized component.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: November 23, 2004
    Assignee: Casio Computer Co., Ltd.
    Inventors: Tetsushi Yoshida, Toshiharu Nishino, Tomoko Tano, Kazuhito Sato, Yoshiaki Sawano, Keiichi Ishida
  • Publication number: 20040223102
    Abstract: A liquid crystal display (LCD) realizes a high brightness by using cholesteric liquid crystal (CLC) in a color filter and a polarizer, and improves viewing angles by using a hologram diffuser. The LCD includes a back light unit to produce and supply light, and a collimating sheet to collimate the light supplied by the back light unit. A CLC polarizer transmits left-circularly polarized light from the collimating sheet, and reflects other light. A lower substrate is disposed above the CLC polarizer, and an upper substrate is disposed above the lower substrate and includes a holographic diffuser which diffuses light without altering a polarization of the light. A liquid crystal layer is disposed between the lower substrate and the upper substrate, and a color filter layer which transmits only predetermined wavelengths of light is also disposed between the lower substrate and the upper substrate. An upper linear polarizer is located above the upper substrate.
    Type: Application
    Filed: June 10, 2004
    Publication date: November 11, 2004
    Applicant: LG. Philips LCD Co., Ltd.
    Inventors: Young-Wan Kwon, Jong-Weon Moon
  • Patent number: 6809786
    Abstract: A reflective liquid crystal display device includes a first substrate including a display region and a first non-display region, the first non-display region being disposed at a boundary of the display region. A second substrate faces and is spaced apart from the first substrate, the second substrate including a second non-display region corresponding to a portion larger than the first substrate. A light absorption layer is on an inner surface of the first substrate. A cholesteric liquid crystal color filter (CCF) layer is at the display region and the first non-display region is on the light absorption layer. A common electrode is on the CCF layer. An array element is on an inner surface of the second substrate. A light shielding pattern is on the array element, the light shielding pattern corresponding to the CCF layer at the first non-display region. A retardation plate and a polarizing plate are sequentially formed on the outer surface of the second substrate.
    Type: Grant
    Filed: November 14, 2002
    Date of Patent: October 26, 2004
    Assignee: LG.Philips LCD Co., Ltd.
    Inventor: Joun-Ho Lee
  • Patent number: 6803972
    Abstract: A class of novel structures which make novel use of polymer based reflective polarizing films in an improved polarization conversion system which are useful in liquid crystal projection systems that are easily manufactured, of lower cost, and permit the versatility of higher numerical aperture polarization conversions. Another aspect of the present invention are polarization modulating liquid crystal projection display systems utilizing the polarization conversion systems of the present invention.
    Type: Grant
    Filed: November 20, 1997
    Date of Patent: October 12, 2004
    Assignee: International Business Machines Corporation
    Inventors: Russell Alan Budd, Derek Brian Dove, Rama Nand Singh
  • Patent number: 6800219
    Abstract: The present invention provides a liquid crystal composition comprising a liquid crystal compound having at least one polymerizable group, a photoreactive chiral compound, and a polymerization initiator, wherein a number average molecular weight of the photoreactive chiral compound is from 1,000 to 30,000. The present invention further provides a selectively reflective film including the liquid crystal composition as well as a liquid crystal color filter including the selectively reflective film.
    Type: Grant
    Filed: May 14, 2002
    Date of Patent: October 5, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Mitsuyoshi Ichihashi, Masatoshi Yumoto
  • Publication number: 20040189907
    Abstract: It is aimed to provide a laminated polarizing film having an antistatic function, where static electricity occurs less even if the protective film is peeled off to bond the laminated polarizing film to a liquid crystal cell, and where defects such as bright spots are not caused in display. The aim is achieved by a laminated polarizing film, wherein a reflective polarizing film and an absorptive polarizing film are laminated, and an antistatic layer is further laminated at least either on the outside of the reflective polarizing film or between the reflective polarizing film and the absorptive polarizing film.
    Type: Application
    Filed: March 31, 2003
    Publication date: September 30, 2004
    Applicant: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Toshihiko Tominaga, Naoyasu Nougi, Masaru Honda
  • Patent number: 6798480
    Abstract: To improve optical transmission efficiency without reducing optical reflection efficiency.
    Type: Grant
    Filed: November 20, 2001
    Date of Patent: September 28, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kikuo Ono, Junichi Hirakata, Takahiro Ochiai, Ryuutaro Oke
  • Patent number: 6795145
    Abstract: The invention provides a liquid crystal display device including switching elements and a reflection layer having low heat resistance. The liquid crystal display device is capable of reducing or preventing a degradation in the characteristics of the reflection layer due to heating in the manufacturing process. A liquid crystal display device includes a pair of opposing substrates, and a liquid crystal interposed between the substrates. A reflection layer is formed on the substrate, and switching elements (TFDs) to drive the liquid crystal are formed on the liquid crystal side of the substrate. The reflection layer is formed of any one of a dielectric reflection film, a cholesteric reflection film, and a holographic reflection film.
    Type: Grant
    Filed: September 17, 2002
    Date of Patent: September 21, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Joji Nishimura, Tsuyoshi Maeda, Osamu Okumura
  • Patent number: 6794216
    Abstract: A cholesteric liquid crystal (CLC) color filter substrate for reflective liquid crystal display devices comprises an alignment layer on a black substrate, a cholesteric liquid crystal (CLC) color filter on the alignment layer, the cholesteric liquid crystal (CLC) color filter including sub-color-filters red (R), green (G), and blue (B), and black matrices on boundaries of each of the sub-color filters R, G, and B. In addition, a cholesteric liquid crystal (CLC) color filter substrate for a reflective liquid crystal display devices comprises an alignment layer on a black substrate, a cholesteric liquid crystal (CLC) color filter on the alignment layer, the cholesteric liquid crystal (CLC) color filter including sub-color-filters R, G, and B, and boundaries of each of the sub-color filters R, G and B that reflect incident light having a long wavelength.
    Type: Grant
    Filed: December 27, 2001
    Date of Patent: September 21, 2004
    Assignee: LG.Philips LCD Co., Ltd.
    Inventor: Byung-Soo Ko
  • Patent number: 6795149
    Abstract: This invention relates to a liquid crystal display device, comprising at least one retardation film (4), a nematic liquid crystal layer (5), and a light reflecting RGB patterned cholesteric color filter (6), for reflecting either essentially left-circular or right-circular polarized light, being characterized in that said liquid crystal layer (5) is a super twisted nematic liquid crystal layer having a twist angle in the interval 180-270 degrees, and in that the summed retardation R of the retardation film or retardation films and the liquid crystal layer is equal to approximately R=(3+2n)&lgr;/4, where n=0,1,2,3 . . . .
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: September 21, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Joost Peter André Vogels, Frans Leenhouts, Peter Van De Witte
  • Patent number: 6795148
    Abstract: The invention provides a transflective liquid crystal display device in which the brightness in a transmissive mode is enhanced to have excellent visibility. A liquid crystal display device of the present invention has an upper substrate and a lower substrate opposing each other and liquid crystal held between the upper substrate and the lower substrate. A transflective layer including cholesteric liquid crystal films are disposed above the lower substrate. A backlight is also provided. Retardation layers and polarizers are disposed outside the upper substrate and the lower substrate, respectively, in that order from the substrate sides. A pigmented color filter layer including pigmented films underlies the transflective layer to transmit light of the same color as that of light selectively reflected at the respective cholesteric liquid crystal films.
    Type: Grant
    Filed: October 24, 2002
    Date of Patent: September 21, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Kinya Ozawa, Osamu Okumura
  • Patent number: 6788368
    Abstract: The reflective liquid crystal display device comprises a polarizing plate disposed forwardly of a liquid crystal cell, a relector which is disposed on backside of the liquid crystal cell and reflects an incident light, and a light-scattering sheet which is disposed forwardly of the reflector and scatters the incident light isotopically. The light-scattering sheet can be prepared with the use of a spinodal decomposition method of coating a mixture liquid containing a plurality of polymers varying in refractive index on a transparent support and evaporating or removing a solvent to form a light-scattering layer having a droplet phase structure. The light-scattering layer includes a light-scattering layer showing a maximum intensity of the scattered-light at scattering angles of 3 to 40°, and a light-scattering layer showing maximums intensity of the scattered-light respectively at smaller angles of 2 to 2° and larger angle &thgr;b.
    Type: Grant
    Filed: November 23, 2001
    Date of Patent: September 7, 2004
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Hiroshi Takahashi, Yoshiyuki Nishida, Masaya Omura, Shuji Nakatsuka
  • Patent number: 6788369
    Abstract: A selectively reflective film and a process for producing the selectively reflective film, comprising the steps of forming on a substrate, a layer of a liquid crystal composition comprising a liquid crystal compound, a photoreactive chiral compound and a polymerization initiator; irradiating the layer with a first light to establish a distribution of exposure in the liquid crystal composition; raising the temperature of the liquid crystal composition layer to transform the composition into a liquid crystal state, thereby forming an area where selective reflection is attained in accordance with the distribution of exposure; and irradiating the liquid crystal composition with a second light to cause polymerization or cross-linking and thereby harden the composition.
    Type: Grant
    Filed: May 28, 2002
    Date of Patent: September 7, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Mitsuyoshi Ichihashi
  • Publication number: 20040160557
    Abstract: The invention relates to a method of providing a decorative coating or text or the like on articles, like shavers, GSM's, cards, etc. The coating comprises a region-wise optically modified (patterned) cholesteric liquid crystalline layer, which is transferred onto a surface of the article by means of a transfer operation. The so-called in-mold decoration technique has been found to be very advantageous for the transfer of decorative (patterned) cholesteric liquid crystalline layers. In this technique the layer is (releasably) deposited on a plastic carrier foil and provided with a layer of adhesive. The assembly is inserted in an injection mold before the injection molding of polymer material starts. In this way decorative coatings (e.g. multi color images) and texts or the like can be even applied onto, non-even and slightly curved substrates.
    Type: Application
    Filed: February 13, 2004
    Publication date: August 19, 2004
    Inventors: Peter Van De Witte, Johan Lub
  • Patent number: 6776491
    Abstract: A display apparatus is characterized by having a display panel for displaying an image, a light source for supplying light to the display panel, and a flat-surface lighting surface member which has a lighting surface emitting light, radiated from the light source, as flat-surface light while being arranged with the display panel. A housing contains the display panel, the light source, and the flat-surface lighting surface member. The housing further includes a window through light passes the flat-surface lighting surface member and leaks to the outside.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: August 17, 2004
    Assignee: International Business Machines Corporation
    Inventors: Fusanobu Nakamura, Fumio Tamura, Yoshimasa Kiyotani, Mitsuo Horiuchi
  • Patent number: 6778238
    Abstract: A reflective liquid crystal display device includes first and second substrates facing and spaced apart from each other; a first transparent electrode beneath the first substrate; a light absorption layer on the second substrate; a cholesteric liquid crystal (CLC) color filter layer on the light absorption layer, the CLC color filter layer being multi-layered and each layer of the CLC color filter including sub-color filters for red, green and blue colors arranged in an alternating order; a second transparent electrode on the CLC color filter layer; and a liquid crystal layer interposed between the first and second transparent electrodes. The CLC color filter layer may be single-layered and each sub-color filter may include a plurality of regions having a different central wavelength of reflection. The CLC color filter layer may be multi-layered with each sub-color filter including a plurality of regions having a different central wavelength of reflection.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: August 17, 2004
    Assignee: LG. Philips LCD Co., Ltd.
    Inventors: Jong-Weon Moon, Sunghoe Yoon
  • Publication number: 20040150772
    Abstract: A reflector for reflecting a broad bandwidth of electromagnetic (EM) radiation, comprising a sheet comprising a large plurality of pairs of layers of transparent polymer material parallel to a surface of the sheet, each pair of layers having a difference in the index of refraction between the materials in each layer of the pair, the total thickness of each pair of layers in the large plurality of layers varying substantially continuously and non linearly across the thickness of the sheet, is disclosed.
    Type: Application
    Filed: October 31, 2003
    Publication date: August 5, 2004
    Inventors: Sadeg M. Faris, Le Li
  • Publication number: 20040141120
    Abstract: Variable optical attenuators (VOAs) are provided, based on electrically switchable CLC reflective polarizers. The reflectivity of the described reflective VOAs can theoretically be electrically adjusted between 0% to 100%, and the reflective bandwidth can be easily adjusted. In general, the VOA includes a pair of switchable CLC polarizers and a driver for driving the polarizers. When the electric fields on both polarizers are off, the polarizers serve as two reflective mirrors. When the fields are turned on, the two polarizers are switched into two transparent sheets allowing light to transmit therethrough. Continuously changing the voltages on the two polarizers electrically adjusts the attenuation.
    Type: Application
    Filed: August 26, 2003
    Publication date: July 22, 2004
    Inventors: Sadeg M. Faris, Zhan He
  • Patent number: 6765639
    Abstract: The invention provides a liquid crystal display device that can reliably prevent light leakage in between dot display domains at boundaries to prevent decrease in contrast and to suppress color mixing. The invention can include semitransmissive reflective layer having a cholesteric liquid crystal layer is arranged in dot display domains, and a metal reflective layer is arranged in a BM domain separating the dot display domains. The metal reflective layer can alter the rotational direction of reflected circularly polarized light from that before reflection and the device can create high-contrast liquid crystal display.
    Type: Grant
    Filed: January 10, 2003
    Date of Patent: July 20, 2004
    Assignee: Seiko Epson Corporation
    Inventor: Tsuyoshi Maeda
  • Patent number: 6762870
    Abstract: The invention relates to a projection display device comprising an illumination system having a light source and an optical guiding means for providing an illumination beam, an image display system comprising a display panel for modulating the illumination beam with image information and projecting the image on a screen, and color filter means provided on a wheel, rotatably mounted at its hub, for transmitting colored portions of the illumination beam for illuminating the display panel. In order to simplify the manufacture of the projection display device, the color filter wheel is provided with one or more cholesteric layers for reflecting a portion of the illumination beam not having a predetermined color and having a circular polarization corresponding to a first direction.
    Type: Grant
    Filed: May 20, 2002
    Date of Patent: July 13, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Adrianus Johannes Stephanes Maria De Vaan
  • Patent number: 6760085
    Abstract: A wavelength selecting module includes a first collimator for collimating diverging light to generate a collimated light beam and a liquid crystal cell having a predetermined helical direction. The liquid crystal cell separates a light signal having a specific wavelength among a plurality of light signals of the collimated light beam into a left circularly polarized light and a right circularly polarized light, reflects one of the left and right circularly polarized light signals that has a same optical rotatory direction as the predetermined helical direction toward the first collimator in a first state. The liquid crystal cell passes the plurality of light signals of the collimated light beam in a second state. The liquid crystal cell changes between the first state and the second state in accordance with a change in a voltage applied thereto, thereby switching between selection and non-selection of light having the specific wavelength.
    Type: Grant
    Filed: October 19, 2001
    Date of Patent: July 6, 2004
    Assignees: Nippon Sheet Glass Co., Ltd., Nanox Corporation
    Inventors: Yoshiro Sato, Manabu Takami
  • Patent number: 6757039
    Abstract: This invention relates to paper white cholesteric displays employing a reflective elliptical polarizer. In the reflective mode, the paper white ON state is achieved by a reflective elliptical polarizer in display's planar texture area; and the black OFF state is obtained by cholesteric's depolarization effect and polarizer's filtration effect in display's focal conic texture area. In the transmissive mode, on the other hand, the paper white ON state is created by a back lighting projected onto the focal conic texture area; and the black OFF state is realized in the cholesteric planar texture area. The reflective elliptical polarizer with a broadband reflection and high polarization efficiency delivers a bright neutral white color to both the reflective and transmissive mode cholesteric displays. The reflective elliptical polarizer also provides a solution to the transflective display where the high efficiency front-lit mode and the back-lit mode can be converted automatically.
    Type: Grant
    Filed: June 17, 2002
    Date of Patent: June 29, 2004
    Inventor: Yao-Dong Ma
  • Patent number: 6753044
    Abstract: Disclosed are novel reflective microflakes for use in making “additive-primary” coloring media having improved reflection characteristics over the red, green and blue super-bright color characteristics, and “super-white” coloring media having Magnesium-Oxide like color characteristics. The coloring media of the present invention provides a palette of colors for imparting color characteristics or forming color images upon surfaces of arbitrary surface geometry. In the preferred embodiments of the invention, the microflakes are made from cholesteric liquid crystal (CLC) material, wherein the pitch of the helices of the liquid crystal molecules in each CLC microflake varies along the thickness dimension (i.e. transverse to the surface) thereof. Depending on the final spiral structure of the materials utilized, the CLC circularly polarizing materials reflect either left-handed or right-handed circularly polarized light.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: June 22, 2004
    Assignee: Reveo, Inc.
    Inventors: Sadeg M. Faris, Le Li
  • Publication number: 20040095531
    Abstract: A color liquid crystal display using reflective color filters using layers of cholesteric liquid crystals is disclosed. The reflective color filters have two different center wavelengths and bandwidths per layer and are stacked in two layers to provide colored light for displays. With various numbers of layers in the stack, different polarization levels are provided. The pixels in the display of the invention are arranged such that multiple adjacent sub-pixels in a layer with the same color makes the color filters easier to manufacture.
    Type: Application
    Filed: May 30, 2003
    Publication date: May 20, 2004
    Inventors: Yingqiu Jiang, Le Li, Aharon Hochbaum, Sameer Vartak, Hristina Galabova, Richard Wiley, Sadeg M. Faris
  • Patent number: 6738114
    Abstract: Disclosed are liquid crystal phase-retarders and linear polarizers and methods and apparatus for making the same. The liquid crystal phase-retarder is realized by a liquid crystal film structure having one or more phase retardation regions formed therein. Each phase retardation region has an optical axis specified by the direction and depth of orientation of liquid crystal molecules along the surface of the liquid crystal film structure. The liquid crystal linear polarizer is realized by a liquid crystal film structure having a chiral phase region within which liquid crystal molecules are cholesterically ordered (FIG. 3). One or more nematic phase regions are formed along the surface of the liquid crystal film structure within which liquid crystal molecules are oriented along a direction and to a surface depth sufficient to realize one or more phase retardation regions therein having optical axes along the direction of liquid crystal molecules orientation.
    Type: Grant
    Filed: May 4, 1999
    Date of Patent: May 18, 2004
    Assignee: Reveo, Inc.
    Inventor: Sadeg Mustafa Faris