US4781441A
Expired / Lapsed
US
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Method of controlling orientation of liquid crystal, device used therein and liquid crystal device produced thereby
Assignee: Canon Inc
•
Filing: 1984-11-15
•
Granted: 1988-11-01
•
Expires: 2004-11-15
Abstract
Abstract Orientation of a liquid crystal is controlled by first forming a phase boundary of the liquid crystal between a monoaxially anisotropic phase where the liquid crystal molecules are aligned in one direction and a higher temperature phase between a pair of base plates, transforming a part of the higher temperature phase adjacent to the phase boundary under cooling into the monoaxially anisotropic phase where liquid crystal molecules are aligned in parallel with the liquid crystal molecules in the already formed monoaxially anisotropic phase, and successively causing the phase transformation in the direction perpendicular to the phase boundary.
Inventors
- 👤 Junichiro Kanbe
- 👤 Kazuharu Katagiri
- 👤 Shinjiro Okada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:57
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/132; G02F1/133; G02F1/1333; G02F1/133345; G02F1/1337; G02F1/133711; G02F1/137; G02F1/139; G02F1/141
Claims Analysis
Total Claims: 100
Claim 1
Independent Claim
57 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a nucleus-generating member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed at a predetermined distance from the nucleus-generating member; said heat-generating member having a larger heat generating capacity near its ends then its central portion.
Claim 2
Independent Claim
57 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a nucleus-generating member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed at a predetermined distance from the nucleus-generating member; said heat-generating member having a larger heat generating capacity near its ends then its central portion.
Claim 3
Dependent Claim
17 words
The orientation controlling device according to claim 1, wherein said nucleus generating member has a stripe shape.
Claim 4
Dependent Claim
20 words
The orientation controlling device according to claim 2, wherein a plurality of said nucleus generating members are arranged in stripes.
Claim 5
Dependent Claim
22 words
The orientation controlling device according to claim 1, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 6
Dependent Claim
51 words
The orientation controlling device according to claim 4, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 7
Dependent Claim
29 words
The orientation controlling device according to claim 1, wherein said-stripe shaped film resistane heat generating member has a larger width at central portion than those at the end portions.
Claim 8
Dependent Claim
26 words
The orientation controlling device according to claim 1, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 9
Independent Claim
33 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a nucleus-generating member disposed therebetween, and a planar, wedge-shaped film resistance heat-generating member.
Claim 10
Independent Claim
33 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a nucleus-generating member disposed therebetween, and a planar, wedge-shaped film resistance heat-generating member.
Claim 11
Dependent Claim
17 words
The orientation controlling device according to claim 8, wherein said nucleus generating member has a stripe shape.
Claim 12
Dependent Claim
20 words
The orientation controlling device according to claim 8, wherein a plurality of said nucleus generating members are arranged in stripes.
Claim 13
Dependent Claim
22 words
The orientation controlling device according to claim 8, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 14
Dependent Claim
51 words
The orientation controlling device according to claim 11, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 15
Dependent Claim
26 words
The orientation controlling device according to claim 8, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 16
Independent Claim
59 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed at a predetermined distance from the orientation controlling member; said heat-generating member having a larger heat-generating capacity near its ends than its central portion.
Claim 17
Independent Claim
59 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed at a predetermined distance from the orientation controlling member; said heat-generating member having a larger heat-generating capacity near its ends than its central portion.
Claim 18
Dependent Claim
18 words
The orientation controlling device according to claim 14, wherein said monoaxial orientation controlling member has a stripe shape.
Claim 19
Dependent Claim
21 words
The orientation controlling device according to claim 15, wherein a plurality of said monoaxial orientation controlling members are arranged in stripes.
Claim 20
Dependent Claim
22 words
The orientation controlling device according to claim 14, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 21
Dependent Claim
51 words
The orientation controlling device according to claim 17, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 22
Dependent Claim
26 words
The orientation controlling device according to claim 14, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 23
Independent Claim
35 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a planar, wedge-shaped film resistance heat-generating member.
Claim 24
Independent Claim
35 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a planar, wedge-shaped film resistance heat-generating member.
Claim 25
Dependent Claim
32 words
The orientation controlling device according to claim 20, wherein said planer heat generating member generates heat increasing in amount in a direction perpendicular to and leaving from said monoaxial orientation controlling member.
Claim 26
Dependent Claim
18 words
The orientation controlling device according to claim 20, wherein said monoaxial orientation controlling member has a stripe shape.
Claim 27
Dependent Claim
21 words
The orientation controlling device according to claim 20, wherein a plurality of said monoaxial orientation controlling members are arranged in stripes.
Claim 28
Dependent Claim
23 words
The orientation controlling device according to claim 20, wherein said monoaxial orientation controlling member is formed of a resin or an inorganic material.
Claim 29
Dependent Claim
51 words
The orientation controlling device according to claim 24, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 30
Dependent Claim
26 words
The orientation controlling device according to claim 20, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 31
Independent Claim
167 words
A device for controlling orientation of a liquid crystal comprising: providing a cylindrical member between a pair of base plates and contiguous with a liquid crystal interposed between the pair of base plates, forming a monoaxially anistropic phase of the liquid crystal wherein liquid crystal molecules are first aligned in one direction in the vicinity of a boundary with said cylindrical member to leave a different phase of the liquid crystal which is a higher temperature phase than said monoaxially anistropic phase with a phase boundary therebetween. transforming a part of said different phase adjacent to the phase boundary under temperature decrease into the monoaxially anistropic phase where liquid crystal molecules are aligned in parallel with the alignment direction of the liquid crystal molecules in the said monoaxially anistropic phase, and successively causing the phase transformation from the phase boundary in a direction perpendicular to the phase boundary, thereby to form a monodomain of the liquid crystal wherein the liquid crystal molecules are aligned in one direction.
Claim 32
Independent Claim
167 words
A device for controlling orientation of a liquid crystal comprising: providing a cylindrical member between a pair of base plates and contiguous with a liquid crystal interposed between the pair of base plates, forming a monoaxially anistropic phase of the liquid crystal wherein liquid crystal molecules are first aligned in one direction in the vicinity of a boundary with said cylindrical member to leave a different phase of the liquid crystal which is a higher temperature phase than said monoaxially anistropic phase with a phase boundary therebetween. transforming a part of said different phase adjacent to the phase boundary under temperature decrease into the monoaxially anistropic phase where liquid crystal molecules are aligned in parallel with the alignment direction of the liquid crystal molecules in the said monoaxially anistropic phase, and successively causing the phase transformation from the phase boundary in a direction perpendicular to the phase boundary, thereby to form a monodomain of the liquid crystal wherein the liquid crystal molecules are aligned in one direction.
Claim 33
Dependent Claim
14 words
The orientation controlling method according to claim 27, wherein said phase boundary extends linearly.
Claim 34
Dependent Claim
45 words
The orientation controlling method according to claim 27, wherein said different phase has a temperature gradient increasing in a direction perpendicular to and leaving from a nucleus generating member and is transformed into the monoaxially anisotropic phase by being cooled with such a temperature gradient.
Claim 35
Dependent Claim
17 words
The orientation controlling method according to claim 27, wherein said monoaxially anisotropic phase is smectic A phase.
Claim 36
Dependent Claim
23 words
The orientation controlling method according to claim 30, wherein said smectic A phase is cooled to be transformed into a chiral smectic phase.
Claim 37
Dependent Claim
25 words
The orientation controlling method according to claim 31, wherein said chiral smectic phase is chiral smectic C, H, F, I, G, K or J phase.
Claim 38
Dependent Claim
17 words
The orientation controlling method according to claim 31, wherein said chiral smectic phase has a nonspiral structure.
Claim 39
Dependent Claim
31 words
The orientation controlling method according to claim 27, wherein said different phase which is a higher temperature phase than said monoaxially anisotropic is a nematic phase, cholesteric phase or isotropic phase.
Claim 40
Dependent Claim
17 words
The orientation controlling method according to claim 27, wherein said cylindrical member is formed of glass fiber.
Claim 41
Dependent Claim
17 words
The orientation controlling method according to claim 27, wherein a plurality of said cylindrical members are arranged.
Claim 42
Dependent Claim
16 words
The orientation controlling device according to claim 27, wherein said cylindrical member formed of glass fiber.
Claim 43
Dependent Claim
17 words
The orientation controlling device according to claim 27, wherein a plurality of said cylindrical members are disposed.
Claim 44
Dependent Claim
19 words
The orientation controlling device according to claim 27, wherein said heat generating member is a resistance heat generating member.
Claim 45
Dependent Claim
20 words
The orientation controlling device according to claim 27, wherein said heat generating member is a film resistance heat generating member.
Claim 46
Independent Claim
55 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a cylindrical member disposed therebetween, and a stripe-shaped heat-generating member disposed at a predetermined distance from the cylindrical member; said heat-generating member having a larger heat generating capacity near its ends than its central portion.
Claim 47
Independent Claim
55 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a cylindrical member disposed therebetween, and a stripe-shaped heat-generating member disposed at a predetermined distance from the cylindrical member; said heat-generating member having a larger heat generating capacity near its ends than its central portion.
Claim 48
Dependent Claim
30 words
The orientation controlling device according to claim 41, wherein said-stripe shaped film resistane heat generating member has a larger width at the central portion than those at the end portions.
Claim 49
Dependent Claim
26 words
The orientation controlling device according to claim 41, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 50
Independent Claim
31 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a cylindrical member disposed therebetween, and a planar wedge-shaped heat-generating member.
Claim 51
Independent Claim
31 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a cylindrical member disposed therebetween, and a planar wedge-shaped heat-generating member.
Claim 52
Dependent Claim
17 words
The orientation controlling device according to claim 44, wherein said cylindrical member is formed of glass fiber.
Claim 53
Dependent Claim
17 words
The orientation controlling device according to claim 44, wherein a plurality of said cylindrical members are disposed.
Claim 54
Dependent Claim
20 words
The orientation controlling device according to claim 44, wherein said planar heat generating member is a resistance heat generating member.
Claim 55
Dependent Claim
21 words
The orientation controlling device according to claim 44, wherein said planar heat generating member is a film resistance heat generating member.
Claim 56
Dependent Claim
26 words
The orientation controlling device according to claim 44, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 57
Independent Claim
46 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a nucleus-generating member disposed therebetween, and a film resistance heat-generating member disposed in a stripe along the periphery of at least one of the base plates.
Claim 58
Independent Claim
46 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a nucleus-generating member disposed therebetween, and a film resistance heat-generating member disposed in a stripe along the periphery of at least one of the base plates.
Claim 59
Dependent Claim
17 words
The orientation controlling device according to claim 50, wherein said nucleus generating member has a stripe shape.
Claim 60
Dependent Claim
20 words
The orientation controlling device according to claim 51, wherein a plurality of said nucleus generating members are arranged in stripes.
Claim 61
Dependent Claim
22 words
The orientation controlling device according to claim 50, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 62
Dependent Claim
51 words
The orientation controlling device according to claim 53, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 63
Dependent Claim
25 words
The controlling device according to claim 50, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 64
Independent Claim
59 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed at a predetermined distance from the orientation controlling member; said heat-generating member having a larger width at its central portion than at its ends.
Claim 65
Independent Claim
59 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed at a predetermined distance from the orientation controlling member; said heat-generating member having a larger width at its central portion than at its ends.
Claim 66
Dependent Claim
18 words
The orientation controlling device according to claim 56, wherein said monoaxial orientation controlling member has a stripe shape.
Claim 67
Dependent Claim
21 words
The orientation controlling device according to claim 57, wherein a plurality of said monoaxial orientation controlling members are arranged in stripes.
Claim 68
Dependent Claim
22 words
The orientation controlling device according to claim 56, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 69
Dependent Claim
51 words
The orientation controlling device according to claim 59, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 70
Dependent Claim
26 words
The orientation controlling device according to claim 56, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 71
Independent Claim
49 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed in a stripe along the periphery of at lest one of said base plates.
Claim 72
Independent Claim
49 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a monoaxial orientation controlling member disposed therebetween, and a stripe-shaped film resistance heat-generating member disposed in a stripe along the periphery of at lest one of said base plates.
Claim 73
Dependent Claim
18 words
The orientation controlling device according to claim 62, wherein said monoaxial orientation controlling member has a stripe shape.
Claim 74
Dependent Claim
21 words
The orientation controlling device according to claim 63, wherein a plurality of said monoaxial orientation controlling members are arranged in stripes.
Claim 75
Dependent Claim
22 words
The orientation controlling device according to claim 62, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 76
Dependent Claim
51 words
The orientation controlling device according to claim 65, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 77
Dependent Claim
26 words
The orientation controlling device according to claim 62, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 78
Independent Claim
44 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a cylindrical member disposed therebetween, and a heat-generating member disposed in a stripe along the periphery of at least one of said base plates.
Claim 79
Independent Claim
44 words
A device for controlling orientation of a liquid crystal comprising: a cell structure comprising a pair of base plates and a cylindrical member disposed therebetween, and a heat-generating member disposed in a stripe along the periphery of at least one of said base plates.
Claim 80
Dependent Claim
17 words
The orientation controlling device according to claim 68, wherein said cylindrical member is formed of glass fiber.
Claim 81
Dependent Claim
17 words
The orientation controlling device according to claim 69, wherein a plurality of said cylindrical members are disposed.
Claim 82
Dependent Claim
18 words
The orientation controlling device according to claim 68, wherein said heat-generating member is a resistance heat generating member.
Claim 83
Dependent Claim
19 words
The orientation controlling device according to claim 68, wherein said heat-generating member is a film resistance heat generating member.
Claim 84
Dependent Claim
26 words
The orientation controlling device according to claim 68, wherein electroconductive films constituting electrodes are formed on the mutually opposed faces of said pair of base plates.
Claim 85
Independent Claim
119 words
A method of controlling orientation of a liquid crystal comprising: providing a cell structure having first and second ends and comprising a pair of base plates and a liquid crystal capable of forming a monoaxially anisotropic phase at specific temperatures and a higher temperature phase at temperatures higher than said specific temperatures, and movable heating means capable of moving relative to the cell structure, and causing said movable heating member to move relative to the cell structure from the first end to the second end, whereby said liquid crystal is caused to form said higher temperature phase at portions heated by the movable heating members and then to form said monoaxial anisotropic phase during the subsequent temperature decreasing stage.
Claim 86
Independent Claim
119 words
A method of controlling orientation of a liquid crystal comprising: providing a cell structure having first and second ends and comprising a pair of base plates and a liquid crystal capable of forming a monoaxially anisotropic phase at specific temperatures and a higher temperature phase at temperatures higher than said specific temperatures, and movable heating means capable of moving relative to the cell structure, and causing said movable heating member to move relative to the cell structure from the first end to the second end, whereby said liquid crystal is caused to form said higher temperature phase at portions heated by the movable heating members and then to form said monoaxial anisotropic phase during the subsequent temperature decreasing stage.
Claim 87
Dependent Claim
39 words
The orientation controlling method according to claim 74, wherein said cell structure is provided with a nucleus generating member and said monoaxially anisotropic phase is initially formed along the boundary between said liquid crystal and the nucleus generating member.
Claim 88
Dependent Claim
17 words
The orientation controlling method according to claim 75, wherein said nucleus generating member has a stripe shape.
Claim 89
Dependent Claim
22 words
The orientation controlling method according to claim 76, wherein said nucleus generating member is formed of a resin or an inorganic material.
Claim 90
Dependent Claim
51 words
The orientation controlling method according to claim 77, wherein said resin is at least one member selected from the group consisting of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin and photoresist resins.
Claim 91
Dependent Claim
20 words
The orientation controlling method according to claim 74, wherein said cell structure is provided with a plurality of spacer members.
Claim 92
Dependent Claim
15 words
The orientation controlling method according to claim 79, wherein said spacer member have stripe shapes.
Claim 93
Dependent Claim
17 words
The orientation controlling method according to claim 74, wherein said monoaxially anisotropic phase is a smectic phase.
Claim 94
Dependent Claim
16 words
The orientation controlling method according to claim 81, wherein said smectic phase is smectic A phase.
Claim 95
Dependent Claim
23 words
The orientation controlling method according to claim 82, wherein said smectic A phase is cooled to be transformed into a chiral smectic phase.
Claim 96
Dependent Claim
17 words
The orientation controlling method according to claim 83, wherein said chiral smectic phase has a nonspiral structure.
Claim 97
Dependent Claim
31 words
The orientation controlling method according to claim 74, wherein said different phase which is a higher temperature phase than said monoaxially anisotropic is a nematic phase, cholesteric phase or isotropic phase.
Claim 98
Dependent Claim
25 words
The orientation controlling method according to claim 83, wherein said chiral smectic phase is chiral smectic C, H, F, I, G, K or J phase.
Claim 99
Dependent Claim
127 words
A liquid crystal device obtained through a method of controlling orientation of a liquid crystal, which method comprises: providing a cell structure having first and second ends and comprising a pair of base plates and a liquid crystal capable of forming a monoaxially anisotropic phase at specific temperatures and a higher temperature phase at temperatures higher than said specific temperatures, and movable heating means capable of moving relative to the cell structure, and causing said movable heating member to move relative to the cell structure from the first end to the second end, whereby said liquid crystal is caused to form said higher temperature phase at portions heated by the movable heating members and then to form said monoaxial anisotropic phase during the subsequent temperature decreasing stage.
Claim 100
Dependent Claim
127 words
A liquid crystal device obtained through a method of controlling orientation of a liquid crystal, which method comprises: providing a cell structure having first and second ends and comprising a pair of base plates and a liquid crystal capable of forming a monoaxially anisotropic phase at specific temperatures and a higher temperature phase at temperatures higher than said specific temperatures, and movable heating means capable of moving relative to the cell structure, and causing said movable heating member to move relative to the cell structure from the first end to the second end, whereby said liquid crystal is caused to form said higher temperature phase at portions heated by the movable heating members and then to form said monoaxial anisotropic phase during the subsequent temperature decreasing stage.
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