Patent US4865903A successfully refreshed from Google Patents.
Patent US5467209A successfully refreshed from Google Patents.
US5467209A
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US
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Ferroelectric liquid crystal device with particular layer thicknesses at non-pixel portions and pixel portions
Assignee: Canon Inc
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Filing: 1993-01-22
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Granted: 1995-11-14
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Expires: 2013-01-22
Abstract
Abstract A ferroelectric liquid crystal device is constituted by a pair of substrates each having thereon a group of display electrodes, and a ferroelectric liquid crystal disposed between the substrates. Liquid crystal movement causing yellowing or local increase in liquid crystal layer thickness is minimized in the device by forming a substantial in liquid crystal layer thickness between a pixel part and a non-pixel part and/or by forming a groove having minute convexities with a maximum diameter of at least 0.1 μm at non-pixel parts on a substrate so that the groove extends in a direction forming an angle of 45-135 degrees with a normal to smectic layers of the liquid crystal.
Inventors
- 👤 Yoshio Hotta
- 👤 Yukio Hanyu
- 👤 Tadashi Mihara
- 👤 Yasuto Kodera
- 👤 Katsutoshi Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:09
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/133371; G02F1/137; G02F1/139; G02F1/141
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
81 words
A liquid crystal device, comprising: a pair of substrates each having thereon a group of display electrodes, and a chiral smectic liquid crystal disposed in a layer between the substrates, wherein the liquid crystal layer has a substantially uniform thickness d at a portion sandwiched by an opposite pair of display electrodes and a thickness D at a portion sandwiched by a display electrode on one substrate and a non-electrode portion between neighboring display electrodes on the other substrate, satisfying D-d≧d/2.
Claim 2
Dependent Claim
81 words
A liquid crystal device, comprising: a pair of substrates each having thereon a group of display electrodes, and a chiral smectic liquid crystal disposed in a layer between the substrates, wherein the liquid crystal layer has a substantially uniform thickness d at a portion sandwiched by an opposite pair of display electrodes and a thickness D at a portion sandwiched by a display electrode on one substrate and a non-electrode portion between neighboring display electrodes on the other substrate, satisfying D-d≧d/2.
Claim 3
Dependent Claim
45 words
A device according to claim 1, wherein said chiral smectic liquid crystal is placed in a uniform alignment state satisfying a relationship of H>θa>H/2, wherein H denotes a half of cone angle and θa denotes an apparent tilt angle of the chiral smectic liquid crystal.
Claim 4
Dependent Claim
19 words
A device according to claim 1, wherein the display electrodes on each substrate is covered with an alignment film.
Claim 5
Dependent Claim
21 words
A device according to claim 1, wherein said portion between neighboring display electrodes has a width of at most 20 μm.
Claim 6
Dependent Claim
25 words
A device according to claim 1, wherein the liquid crystal layer thickness at the portion sandwiched by the opposite pair of electrodes is 0.5-8 μm.
Claim 7
Dependent Claim
96 words
A liquid crystal device, comprising: a pair of substrates each having thereon a group of display electrodes, and a chiral smectic liquid crystal disposed in a layer between the substrates, wherein the liquid crystal layer has a thickness d at a portion sandwiched by an opposite pair of display electrodes, and only one of said pair of substrates is provided with a projection at a non-electrode portion between neighboring display electrodes so as to form a liquid crystal layer in a thickness D between the projection and a display electrode on the other substrate, satisfying d-D≧d/2.
Claim 8
Dependent Claim
96 words
A liquid crystal device, comprising: a pair of substrates each having thereon a group of display electrodes, and a chiral smectic liquid crystal disposed in a layer between the substrates, wherein the liquid crystal layer has a thickness d at a portion sandwiched by an opposite pair of display electrodes, and only one of said pair of substrates is provided with a projection at a non-electrode portion between neighboring display electrodes so as to form a liquid crystal layer in a thickness D between the projection and a display electrode on the other substrate, satisfying d-D≧d/2.
Claim 9
Dependent Claim
45 words
A device according to claim 6, wherein said chiral smectic liquid crystal is placed in a uniform alignment state satisfying a relationship of H>θa>H/2, wherein H denotes a half of cone angle and θa denotes an apparent tilt angle of the chiral smectic liquid crystal.
Claim 10
Dependent Claim
19 words
A device according to claim 6, wherein the display electrodes on each substrate are covered with an alignment film.
Claim 11
Dependent Claim
21 words
A device according to claim 6, wherein said portion between neighboring display electrodes has a width of at most 20 μm.
Claim 12
Dependent Claim
25 words
A device according to claim 6, wherein the liquid crystal layer thickness at the portion sandwiched by the opposite pair of electrodes is 0.5-8 μm.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1998-11-13 | 1999-05-15 | 1999-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-11-13 | 2003-05-15 | 2003-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-11-13 | 2007-05-15 | 2007-11-14 | $7700.00 | Window Closed / Lapsed |