US5786879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal device with different pretilt in peripheral portion
Assignee: Canon Inc
•
Filing: 1996-10-30
•
Granted: 1998-07-28
•
Expires: 2016-10-30
Abstract
Abstract A liquid crystal device is constituted by a pair of oppositely disposed substrates having opposing inner surfaces and opposing electrodes thereon, and a chiral smectic liquid crystal disposed between the opposing electrodes. The liquid crystal device has an effective optical modulation region and a peripheral region outside the effective optical modulation region. In the device, liquid crystal molecules in the peripheral region have a pretilt angle which is larger than a pretilt angle of liquid crystal molecules in the effective optical modulation region. As a result, a local pressure irregularity or a cell thickness change caused by a liquid crystal molecular movement along an extension of the device is effectively suppressed.
Inventors
- 👤 Yasuto Kodera
- 👤 Yoshio Hotta
- 👤 Yukio Hanyu
- 👤 Tadashi Mihara
- 👤 Sunao Mori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:07
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133753; G02F1/137; G02F1/139; G02F1/141; G02F1/133388; G02F1/133761
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
99 words
A liquid crystal device comprising a pair of oppositely disposed substrates having opposing inner surfaces and opposing electrodes thereon, and a chiral smectic liquid crystal disposed between the opposing electrodes, said liquid crystal device having an effective optical modulation region and a peripheral region outside the effective optical modulation region; wherein liquid crystal molecules in the peripheral region have a pretilt angle which is larger than a pretilt angle of liquid crystal molecules in the effective optical modulation region; and the liquid crystal molecules in the effective optical modulation region have a pretilt angle of at most 5 degrees.
Claim 2
Dependent Claim
99 words
A liquid crystal device comprising a pair of oppositely disposed substrates having opposing inner surfaces and opposing electrodes thereon, and a chiral smectic liquid crystal disposed between the opposing electrodes, said liquid crystal device having an effective optical modulation region and a peripheral region outside the effective optical modulation region; wherein liquid crystal molecules in the peripheral region have a pretilt angle which is larger than a pretilt angle of liquid crystal molecules in the effective optical modulation region; and the liquid crystal molecules in the effective optical modulation region have a pretilt angle of at most 5 degrees.
Claim 3
Dependent Claim
34 words
A liquid crystal device according to claim 1, wherein said chiral smectic liquid crystal comprise liquid crystal molecules susceptible of movement along the inner surfaces of the substrates under application of an electric field.
Claim 4
Dependent Claim
21 words
A liquid crystal device according to claim 1, wherein the inner surface of at least one of the substrates is roughened.
Claim 5
Dependent Claim
24 words
A liquid crystal device according to claim 1, wherein a plurality of adhesive particles and a plurality of spacers are disposed between the substrates.
Claim 6
Dependent Claim
29 words
A liquid crystal device according to claim 1, wherein the opposing electrodes are supplied with a drive signal comprising bipolar pulses, with respect to a reference potential, for driving.
Claim 7
Dependent Claim
19 words
A liquid crystal device according to claim 1, wherein the peripheral region is optically covered with a masking member.
Claim 8
Dependent Claim
19 words
A liquid crystal device according to claim 1, wherein said chiral smectic liquid crystal is a ferroelectric liquid crystal.
Claim 9
Dependent Claim
34 words
An image forming apparatus, comprising an exposure means including a liquid crystal device according to claim 1, a photosensitive means to be exposed by the exposure means, a developing means and a transfer means.
Claim 10
Dependent Claim
33 words
An image forming apparatus, comprising a display means including a liquid crystal device according to claim 1, a drive means for supplying drive signals to the display means, and at least one polarizer.
Claim 11
Dependent Claim
44 words
An image forming apparatus, comprising a display means including a liquid crystal device according to claim 1, a drive means for supplying drive signals to the display means, and at least one polarizer and an image source for supplying image signals to be displayed.
Claim 12
Dependent Claim
16 words
An image display apparatus according to claim 1, wherein said image source comprises an image sensor.
Claim 13
Dependent Claim
15 words
An image display apparatus according to claim 1, wherein said image source comprises a computer.
Claim 14
Dependent Claim
33 words
A liquid crystal device according to claim 1, wherein the liquid crystal is homeotropically aligned in the peripheral region, and is aligned to form a bookshelf structure in the effective optical modulation region.
Claim 15
Dependent Claim
38 words
A liquid crystal device according to claim 13, wherein the inner surface of one substrate is coated with an alignment film which has been rubbed in the effective optical modulation region and not rubbed in the peripheral region.
Claim 16
Dependent Claim
20 words
A liquid crystal device according to claim 13, wherein said chiral smectic liquid crystal is a fluorine-containing ferroelectric liquid crystal.
References Cited (Backward Citations)
US5013137A
Cited
JPS62203128A
Cited
US5293534A
Cited
US5182662A
Cited
US5454976A
Cited
US5204706A
Cited
JPH04258924A
Cited
US5204766A
Cited
US5276542A
Cited
EP0525673A2
Cited
EP0550846A1
Cited
US5381256A
Cited
JPH05188348A
Cited
US5437812A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-07-27 | 2002-01-26 | 2002-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-07-27 | 2006-01-26 | 2006-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-07-27 | 2010-01-26 | 2010-07-28 | $7700.00 | Window Closed / Lapsed |