Patents by Inventor Masanobu Asaoka

Masanobu Asaoka has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5594571
    Abstract: A ferroelectric liquid crystal device of a cell structure having a suppressed increase of cell thickness along a cell side is constituted by disposing a ferroelectric liquid crystal between a pair of electrode plates each sequentially provided with an electrode, an insulating film and an alignment film on a substrate. The aligment film is provided with a surface unevenness for suppressing a liquid crystal movement causing the increase in cell thickness. The surface unevenness is provided to the aligment film directly or to the insulating film below the alignment film, e.g., by wet forming the relevant film by using at least two solvents having different boiling points or dispersing fine particles within the relevant film, optionally followed by removal of the fine particles.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: January 14, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukio Hanyu, Kenji Onuma, Yoshio Hotta, Osamu Taniguchi, Hideaki Takao, Masanobu Asaoka, Tadashi Mihara, Yasuto Kodera, Makoto Kojima, Katsutoshi Nakamura, Takatsugu Wada
  • Patent number: 5587211
    Abstract: A liquid crystal device is constituted by a pair of substrates each having an electrode thereon and disposed in parallel with each other, and a liquid crystal disposed between the substrates. At least one of the substrates has thereon an organic alignment film formed from at least one species of polymer including a polymer having an average molecular weight of at most 30,000.
    Type: Grant
    Filed: April 18, 1995
    Date of Patent: December 24, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takeshi Togano, Hideaki Takao, Masanobu Asaoka, Makoto Kojima
  • Patent number: 5576864
    Abstract: A liquid crystal device is constituted by a pair of substrates, and a liquid crystal disposed between the substrates. At least one of the substrates has thereon an alignment film. The alignment film is characterized in that (1) it has a surface energy of at most 35 dyne/cm before rubbing and has been rubbed to have a refractive index anisotropy of at least 0.02, or (2) it has been rubbed to have a surface energy difference .DELTA.E of at least 9 dyne/cm and a difference .DELTA..delta. in dispersion term of the surface energy of at least 6 dyne/cm between before and after the rubbing. The alignment film is effective in providing a high contrast and decreasing a delay in optical response causing after-image.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: November 19, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideaki Takao, Masanobu Asaoka, Makoto Kojima
  • Patent number: 5571580
    Abstract: A liquid crystal device is constituted by disposing a liquid crystal between a pair of substrates; at least one of which has thereon an alignment film comprising a polymer selected from Polymers (I)-(III) below:Polymer (I) which is a polymer composite comprising at least two polymer components including a polyamide represented by a structural unit of the following formula (1): ##STR1## wherein R.sub.11 and R.sub.12 independently denote an alkyl group having 1-10 carbon atoms or a fluoroalkyl group having 1-10 carbon atoms;Polymer (II) which is a composite polyamide having at least two species of dicarboxylic acid-originated units each represented by formula (2) below: ##STR2## wherein R.sub.21 denotes a divalent organic residue group including an aromatic ring; and a diamine-originated unit represented by formula (3) below: ##STR3## wherein R.sub.22 and R.sub.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 5, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masanobu Asaoka, Hideaki Takao, Takeshi Togano, Makoto Kojima
  • Patent number: 5552193
    Abstract: A liquid crystal device is constituted by disposing a liquid crystal between a pair of substrates; at least one of which has thereon an alignment film comprising a polymer selected from Polymers (I)-(III) below:Polymer (I), which is a polymer composite comprising at least two polymer components including a polyamide represented by a structural unit of the following formula (1): ##STR1## wherein R.sub.11 and R.sub.12 independently denote an alkyl group having 1-10 carbon atoms or a fluoroalkyl group having 1-10 carbon atoms;Polymer (II) which is a composite polyamide having at least two species of dicarboxylic acid-originated units each represented by formula (2) below: ##STR2## wherein R.sub.21 denotes a divalent organic residue group including an aromatic ring; and a diamine-originated unit represented by formula (3) below: ##STR3## wherein R.sub.22 and R.sub.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: September 3, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masanobu Asaoka, Hideaki Takao, Takeshi Togano, Makoto Kojima
  • Patent number: 5523872
    Abstract: A liquid crystal apparatus includes: (a) a liquid crystal panel having a longitudinal direction and containing therein a chiral smectic liquid crystal comprising plural layers of liquid crystal molecules aligned to have a common layer normal, each layer being composed of a plurality of liquid crystal molecules, each liquid crystal molecule being oriented to one of plural stable orientation states in the absence of an electric field; and (b) a panel supporting means comprising two fixing axes which extend in parallel with the longitudinal direction of the liquid crystal panel and fix the peripheral sides of the liquid crystal panel, the fixing axes forming an intersection angle .theta..sub.1 in the range of 0-25 degrees with the common layer normal.
    Type: Grant
    Filed: February 23, 1994
    Date of Patent: June 4, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukio Hanyu, Masanobu Asaoka
  • Patent number: 5518782
    Abstract: A liquid crystal device is constituted by disposing a chiral smectic liquid crystal between a pair of substrates. At least one of the pair of substrates is provided with an alignment film of a nitrogen-containing polymer, such as a polyimide, a polyamide or a polyamideimide, having a main chain including a structural unit represented by the following formula (I): ##STR1## wherein R.sub.1 denotes a divalent aliphatic or aromatic group, and R.sub.2 and R.sub.3 independently denote a monovalent aliphatic or aromatic group, and X denotes a positive integer.
    Type: Grant
    Filed: December 14, 1993
    Date of Patent: May 21, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideaki Takao, Masanobu Asaoka, Takeshi Togano, Makoto Kojima
  • Patent number: 5514297
    Abstract: A ferroelectric chiral smectic liquid crystal composition, comprising at least one compound represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 respectively denote a linear or branched alkyl group having 1-18 carbon atoms capable of having a substituent; X.sub.1 and X.sub.2 respectively denote a single bond, ##STR2## Y.sub.1 denotes --CH.sub.2 O-- or --OCH.sub.2 ; and m and n are respectively 1 or 2; and at least one compound represented by the following formula (II): ##STR3## wherein R.sub.3 and R.sub.4 respectively denote a linear or branched alkyl group having 1-18 carbon atoms capable of having a substituent, at least one of R.sub.3 and R.sub.4 being optically active; and; X.sub.3 and X.sub.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: May 7, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shinjo, Takao Takiguchi, Hiroyuki Kitayama, Kazuharu Katagiri, Masahiro Terada, Takeshi Togano, Masataka Yamashita, Masanobu Asaoka
  • Patent number: 5510159
    Abstract: A liquid crystal device is constituted by a pair of substrates each provided with a transparent electrode, and a liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising (i) a polyimide including principally a recurring unit of the following structural formula (I): ##STR1## wherein R.sub.11 denotes a tetravalent organic group, and R.sub.12 and R.sub.13 denote the same or different alkyl or perfluoroalkyl groups having 1-10 carbon atoms, and also at most 20 mol. % of a recurring monoamine unit of the following structural formula (II): ##STR2## wherein R.sub.21 and R.sub.22 denote the same or different alkyl or perfluoroalkyl groups having 1-10 carbon atoms, and X denotes an aromatic group, a heterocyclic group or a derivative group thereof; or (ii) a polyimide obtained through a reaction of at least two species of tetracarboxylic anhydrides of the following formula (III): ##STR3## wherein R.sub.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: April 23, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masanobu Asaoka, Hideaki Takao, Yukio Hanyu, Makoto Kojima
  • Patent number: 5501818
    Abstract: A ferroelectric chiral smectic liquid crystal composition, comprising: at least one compound represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 respectively denote a linear or branched alkyl group having 1-18 carbon atoms capable of having a substituent of C.sub.1 -C.sub.12 alkoxy group; X.sub.1 and X.sub.2 respectively denote a single bond, --O--, ##STR2## at least one compound represented by the following formula (II): ##STR3## wherein R.sub.3 and R.sub.4 respectively denote a linear or branched alkyl group having 1-18 carbon atoms capable of having a substituent; X.sub.3 and X.sub.4 respectively denote a single bond, --O--, ##STR4## Z.sub.1 denotes ##STR5## --CH.sub.2 O--, --OCH.sub.2 -- or a single bond; ##STR6## respectively denote ##STR7## denotes ##STR8## with proviso that at least one of ##STR9## and at least one compound represented by the following formula (III): ##STR10## wherein R.sub.
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: March 26, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shinjo, Takao Takiguchi, Hiroyuki Kitayama, Kazuharu Katagiri, Masataka Yamashita, Masahiro Terada, Takeshi Togano, Masanobu Asaoka
  • Patent number: 5482652
    Abstract: A ferroelectric chiral smectic liquid crystal composition is provided with a fast response speed and a less temperature dependency of the response speed by containing at least one mesomorphic compound represented by the formula (1) below: ##STR1## wherein R.sub.1 denotes an alkyl group having 1-16 carbon atoms and capable of having a substituent; R.sub.2 denotes an alkyl group, alkoxy group, alkoxycarbonyl group, acyloxy group or alkoxycarbonyloxy group each having 1-16 carbon atoms and capable of having a substituent; and ##STR2## respectively denotes ##STR3## each capable of having a substituent.
    Type: Grant
    Filed: June 27, 1994
    Date of Patent: January 9, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shinjo, Masahiro Terada, Toshiharu Uchimi, Akio Yoshida, Takeshi Togano, Masanobu Asaoka, Takashi Iwaki
  • Patent number: 5481387
    Abstract: A ferroelectric liquid crystal element has a ferroelectric liquid crystal with an orientation state represented by .theta.<.alpha.+.delta. wherein .alpha. is a pretilt angle of the ferroelectric liquid crystal, .theta. is a tilt angle, and .delta. is an inclination angle of an Sm*C layer. In another embodiment is a liquid crystal element having a chiral smectic liquid crystal satisfying T.sub.1 /T.sub.2 <2.5 in a first orientation state wherein T.sub.2 is a pulse width threshold values of a portion in a second orientation state adjacent lightning and hairpin defects and T.sub.1 is a pulse width threshold value in a first orientation state of a portion outside of the T.sub.2 portion. In both embodiments, the ferroelectric liquid crystal exhibits at least two stable states in orientation. An angle .theta..sub.a midway between optical axes of these two stable states and the tilt angle 8 of the ferroelectric liquid crystal satisfy the condition .theta.>.theta..sub.a >.theta./2.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: January 2, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukio Hanyu, Yutaka Inaba, Masanobu Asaoka, Osamu Taniguchi, Kenji Shinjo, Toshiharu Uchimi
  • Patent number: 5464668
    Abstract: A liquid crystal device includes: a liquid crystal disposed between a pair of substrates; at least one of which has thereon an alignment film comprising a polyimide or polyamide imide formed by reaction between a diamine component of formula (1) shown below and at least two acid components selected from tetracarboxylic acid components having a structure of formula (2) shown below at least including a naphthalenetetracarboxylic acid component, and dicarboxylic acid components having a structure of formula (3) shown below; ##STR1## wherein R.sub.1 and R.sub.2 independently denote an alkyl group or a fluoroalkyl group having 1-10 carbon atoms; ##STR2## wherein A and B respectively denote a tetravalent or divalent organic residue comprising an aromatic ring, aromatic polycyclic ring or condensed polycyclic ring.
    Type: Grant
    Filed: February 4, 1993
    Date of Patent: November 7, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masanobu Asaoka, Hideaki Takao, Takeshi Togano, Makoto Kojima
  • Patent number: 5453861
    Abstract: A liquid crystal device showing improved uniform alignment characteristic and switching characteristic is constituted by a pair of an upper substrate and a lower substrate, and a chiral smectic liquid crystal disposed between the upper and lower substrates. Each of the upper and lower substrates has thereon an electrode for applying a voltage to the liquid crystal and a uniaxial alignment film. The alignment films on the upper and lower substrates are provided with uniaxial alignment axes which cross each other so that the direction of crossing of the uniaxial alignment axes from the lower substrate to the upper substrate is identical to the direction of helical twist in cholesteric phase of the chiral smectic liquid crystal, and the chiral smectic liquid crystal is disposed in such an alignment state that the liquid crystal shows a pretilt angle .alpha., a cone angle H, an inclination angle .delta. of SmC.sup.* layer, and an apparent tilt angle .theta.a satisfying relationships of: H<.alpha.+.delta.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: September 26, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shinjo, Hiroyuki Kitayama, Masanobu Asaoka, Masahiro Terada, Syuji Yamada, Hiroshi Mizuno
  • Patent number: 5426525
    Abstract: A liquid crystal device is constituted by a pair of substrates; an alignment film comprising a polyimide which has a fluorine-containing substituent in its diamine-originated moiety, disposed on at least one of the pair of substrates and subjected to an aligning treatment; and a chiral smectic liquid crystal disposed between the pair of substrates in an alignment state where its helical structure is suppressed. The chiral smectic liquid crystal is placed in an alignment state of forming an aligned region occupying an area which is at least 95% of the effective display region of the liquid crystal device. The aligned region includes a plurality of unidirectionally bent layers each organized by plural liquid crystal molecules in chiral smectic phase.
    Type: Grant
    Filed: May 3, 1993
    Date of Patent: June 20, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukio Hanyu, Junichiro Kanbe, Hideyuki Sugioka, Yutaka Inaba, Masanobu Asaoka
  • Patent number: 5422749
    Abstract: A liquid crystal device is constituted by a pair of substrates; an alignment film comprising a polyimide which has a fluorine-containing substituent in its carboxylic acid-originated moiety, disposed on at least one of the pair of substrates and subjected to an aligning treatment; and a chiral smectic liquid crystal disposed between the pair of substrates in an alignment state where its helical structure is suppressed. The chiral smectic liquid crystal is placed in an alignment state of forming an aligned region occupying an area which is at least 95% of the effective display region of the liquid crystal device. The aligned region includes a plurality of unidirectionally bent layers each organized by plural liquid crystal molecules in chiral smectic phase.
    Type: Grant
    Filed: May 3, 1993
    Date of Patent: June 6, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukio Hanyu, Junichiro Kanbe, Hideyuki Sugioka, Yutaka Inaba, Masanobu Asaoka
  • Patent number: 5419931
    Abstract: A liquid crystal device is constituted by disposing a liquid crystal between a pair of substrates; at least one of which has thereon an alignment film comprising a polymer selected from Polymers (I)-(III) below:Polymer (I) which is a polymer composite comprising at least two polymer components including a polyamide represented by a structural unit of the following formula (1): ##STR1## wherein R.sub.11 and R.sub.12 independently denote an alkyl group having 1-10 carbon atoms or a fluoroalkyl group having 1-10 carbon atoms;Polymer (II) which is a composite polyamide having at least two species of dicarboxylic acid-originated units each represented by formula (2) below: ##STR2## wherein R.sub.21 denotes a divalent organic residue group including an aromatic ring; and a diamine-originated unit represented by formula (3) below: ##STR3## wherein R.sub.22 and R.sub.
    Type: Grant
    Filed: September 20, 1993
    Date of Patent: May 30, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masanobu Asaoka, Hideaki Takao, Takeshi Togano, Makoto Kojima
  • Patent number: 5419932
    Abstract: A liquid crystal device is formed by applying an alignment film on at least one of a pair of substrates sandwiching a liquid crystal, preferably a chiral smectic liquid crystal. The alignment is formed by a dehydro-cyclization product of a polyamide acid which in turn is a reaction product of naphthalenetetracarboxylic acid or its derivative with a diamine or its derivative. The liquid crystal device provides a high contrast display, particularly by multiplexing drive, which is free from after-image because of quick responsiveness.
    Type: Grant
    Filed: January 24, 1994
    Date of Patent: May 30, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takeshi Togano, Takao Takiguchi, Hideaki Takao, Yukio Hanyu, Masanobu Asaoka, Takashi Iwaki
  • Patent number: 5405553
    Abstract: A ferroelectric chiral smectic liquid crystal composition, comprising at least one optically active compound represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 respectively denote a linear or branched alkyl group having 1-18 carbon atoms capable of having a substituent, at least one of R.sub.1 and R.sub.2 being optically active; X.sub.1 denotes --O--, ##STR2## and X.sub.2 denotes a single bond, --O--, ##STR3## and at least one compound represented by the following formula (II): ##STR4## wherein R.sub.3 and R.sub.4 respectively denote a linear or branched optically inactive alkyl group having 1-18 carbon atoms capable of having an alkoxy group of 1-12 carbon atoms; X.sub.3 and X.sub.4 respectively denote a single bond, --O--, ##STR5## and m and n are respectively 0, 1 or 2 with proviso that both of m and n are not 0.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: April 11, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiro Terada, Takeshi Togano, Masataka Yamashita, Takao Takiguchi, Masanobu Asaoka, Kenji Shinjo, Hiroyuki Kitayama, Shinichi Nakamura
  • Patent number: 5400159
    Abstract: A liquid crystal device is constituted by a pair of substrates, and a liquid crystal disposed between the substrates. At least one of the substrates has thereon an alignment film. The alignment film is characterized in that (1) it has a surface energy of at most 35 dyne/cm before rubbing and has been rubbed to have a refractive index anisotropy of at least 0.02, or (2) it has been rubbed to have a surface energy difference .DELTA.E of at least 9 dyne/cm and a difference .DELTA..delta. in dispersion term of the surface energy of at least 6 dyne/cm between before and after the rubbing. The alignment film is effective in providing a high contrast and decreasing a delay in optical response causing after-image.
    Type: Grant
    Filed: January 12, 1994
    Date of Patent: March 21, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideaki Takao, Masanobu Asaoka, Makoto Kojima