Patent US5844649A successfully refreshed from Google Patents.
US5844649A
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Liquid crystal display
Assignee: Sharp Corp
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Filing: 1997-04-10
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Granted: 1998-12-01
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Expires: 2017-04-10
Abstract
Abstract A liquid crystal display has a liquid crystal layer that is sandwiched between a pair of electrode substrates in a manner so as to contact alignment films, and also has a liquid crystal display element having optical phase-difference plates placed on both sides thereof. The liquid crystal layer is divided into a first division-section and a second division-section that have different sizes and that are oriented by the alignment films in respectively different directions. Further, with respect to the first division-section that has the larger size, an optical phase difference plate is placed so that the index ellipsoid, which identifies the refractive-index anisotropy of the optical phase-difference plate, has an inclined direction to the optical phase-difference plate that is opposite to the pretilt direction of liquid crystal molecules located in the vicinity of the alignment films. Thus, since biased optical characteristics are properly compensated, viewing-angle characteristics in the case of inclined viewing angles can be improved. Consequently, it becomes possible to eliminate the occurrences of a gradation-inverting phenomenon in the up and down directions as well as right and left directions and a coloring phenomenon in the up and down direction, and consequently to improve contrast while eliminating display unevenness.
Inventors
- 👤 Motohiro Yamahara
- 👤 Mitsuaki Hirata
- 👤 Shigeaki Mizushima
- 👤 Noriko Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:48
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133753; G02F1/1335; G02F1/13363; G02F1/133632; G02F1/133761
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
248 words
A liquid crystal display comprising a liquid crystal display element having a pair of light-transmitting substrates that have opposing surfaces, each of the opposing surfaces having a transparent electrode and an alignment film respectively formed thereon, and a liquid crystal layer that is interpolated between the substrates, wherein the transparent electrodes are arranged on the opposing surfaces so as to establish a plurality of display pixels; a pair of polarizers that are placed on both sides of the liquid crystal display element; an optical phase-difference plate that is interpolated at least in either of gaps between the liquid crystal display element and the pair of the polarizers; wherein the liquid crystal layer in each pixel is oriented by the alignment film in different directions so that it is divided into divisions of the liquid crystal layer having respectively different sizes; and wherein the optical phase-difference plate is placed so that an index ellipsoid, which is represented by principal refractive indexes in three directions of the optical phase-difference plate and which identifies anisotropy of the principal refractive indexes of the optical phase-difference plate, is inclined with respect to a surface of the optical phase-difference plate, and so that upon application of a voltage to the transparent electrodes, a tilted direction of liquid crystal molecules in a vicinity of a surface of the corresponding alignment film is opposite to the inclined direction of the index ellipsoid, with respect to the largest division of the liquid crystal layer in the pixel.
Claim 2
Dependent Claim
248 words
A liquid crystal display comprising a liquid crystal display element having a pair of light-transmitting substrates that have opposing surfaces, each of the opposing surfaces having a transparent electrode and an alignment film respectively formed thereon, and a liquid crystal layer that is interpolated between the substrates, wherein the transparent electrodes are arranged on the opposing surfaces so as to establish a plurality of display pixels; a pair of polarizers that are placed on both sides of the liquid crystal display element; an optical phase-difference plate that is interpolated at least in either of gaps between the liquid crystal display element and the pair of the polarizers; wherein the liquid crystal layer in each pixel is oriented by the alignment film in different directions so that it is divided into divisions of the liquid crystal layer having respectively different sizes; and wherein the optical phase-difference plate is placed so that an index ellipsoid, which is represented by principal refractive indexes in three directions of the optical phase-difference plate and which identifies anisotropy of the principal refractive indexes of the optical phase-difference plate, is inclined with respect to a surface of the optical phase-difference plate, and so that upon application of a voltage to the transparent electrodes, a tilted direction of liquid crystal molecules in a vicinity of a surface of the corresponding alignment film is opposite to the inclined direction of the index ellipsoid, with respect to the largest division of the liquid crystal layer in the pixel.
Claim 3
Dependent Claim
70 words
The liquid crystal display as defined in claim 1, wherein: the divisions of the liquid crystal layer include a first division of liquid crystal layer and a second division of liquid crystal layer that is smaller than the first division, and a ratio of sizes of the first division of liquid crystal layer and the second division of liquid crystal layer is set in a range of 6:4 to 19:1.
Claim 4
Dependent Claim
26 words
The liquid crystal display as defined in claim 2, wherein the first and second divisions of liquid crystal layer have orientation directions opposite to each other.
Claim 5
Dependent Claim
91 words
The liquid crystal display as defined in claim 2, wherein: the transparent electrode on one of the opposing surfaces includes signal-electrode lines for applying display-use signal voltages to the pixels and the transparent electrode on the other opposing surface includes scanning-electrode lines for selecting the application of the signal voltages to the pixels for each scanning period, and the first division of liquid crystal layer and the second division of liquid crystal layer are oriented so that a border between the two divisions is inclined with respect to the scanning-electrode lines.
Claim 6
Dependent Claim
26 words
The liquid crystal display as defined in claim 4, wherein the border and the scanning-electrode lines make an angle in a range of 10° to 80°.
Claim 7
Dependent Claim
26 words
The liquid crystal display as defined in claim 5, wherein the border and the scanning-electrode lines make an angle in a range of 20° to 50°.
Claim 8
Dependent Claim
27 words
The liquid crystal display as defined in claim 6, wherein the border crosses an intersection of each of the signal-electrode lines and each of the scanning-electrode lines.
Claim 9
Dependent Claim
72 words
The liquid crystal display as defined in claim 2, wherein: the alignment film on one of the opposing surfaces comprises raised sections, each having tapered faces on both side faces thereof that are inclined with respect to the opposing surface of the corresponding light-transmitting substrate, and a border between the first division of liquid crystal layer and the second division of liquid crystal layer is placed on each of the raised sections.
Claim 10
Dependent Claim
47 words
The liquid crystal display as defined in claim 8, wherein: a height of the raised section is set in a range of 500 to 5000 Å and a width of an upper face of the raised section is set in a range of 5 to 50 μm.
Claim 11
Dependent Claim
38 words
The liquid crystal display as defined in claim 9, wherein said each of the raised sections is formed on each of storage-capacitor electrodes that are formed on the corresponding light-transmitting substrate so as to form a storage capacitor.
Claim 12
Dependent Claim
72 words
The liquid crystal display as defined in claim 2, wherein: the alignment film on one of the opposing surfaces comprises recessed sections, each having tapered faces on both side faces thereof that are inclined with respect to the opposing surface of the corresponding light-transmitting substrate, and a border between the first division of liquid crystal layer and the second division of liquid crystal layer is placed on each of the recessed sections.
Claim 13
Dependent Claim
47 words
The liquid crystal display as defined in claim 11, wherein: a depth of the recessed section is set in a range of 500 to 5000 < and a width of a bottom face of the recessed section is set in a range of 5 to 50 μm.
Claim 14
Dependent Claim
56 words
The liquid crystal display as defined in claim 2, wherein: a color filter is formed on either of the pair of the light-transmitting substrates, and the ratio of sizes of the first division of liquid crystal layer and the second division of liquid crystal layer is determined in accordance with respective colors of the color filter.
Claim 15
Dependent Claim
45 words
The liquid crystal display as defined in claim 13, wherein the ratio is set so that light rays which have respectively passed through the first division of liquid crystal layer and the second division of liquid crystal layer have additive complementary colors to each other.
Claim 16
Dependent Claim
39 words
The liquid crystal display as defined in claim 2, wherein the ratio of sizes of the first division of liquid crystal layer and the second division of liquid crystal layer is set in a range of 7:3 to 9:1.
Claim 17
Dependent Claim
26 words
The liquid crystal display as defined in claim 15, wherein the first and second divisions of liquid crystal layer have orientation directions opposite to each other.
Claim 18
Dependent Claim
91 words
The liquid crystal display as defined in claim 15, wherein: the transparent electrode on one of the opposing surfaces includes signal-electrode lines for applying display-use signal voltages to the pixels and the transparent electrode on the other opposing surface includes scanning-electrode lines for selecting the application of the signal voltages to the pixels for each scanning period, and the first division of liquid crystal layer and the second division of liquid crystal layer are oriented so that a border between the two divisions is inclined with respect to the scanning-electrode lines.
Claim 19
Dependent Claim
26 words
The liquid crystal display as defined in claim 17, wherein the border and the scanning-electrode lines make an angle in a range of 10° to 80°.
Claim 20
Dependent Claim
26 words
The liquid crystal display as defined in claim 18, wherein the border and the scanning-electrode lines make an angle in a range of 20° to 50°.
Claim 21
Dependent Claim
27 words
The liquid crystal display as defined in claim 19, wherein the border crosses an intersection of each of the signal-electrode lines and each of the scanning-electrode lines.
Claim 22
Dependent Claim
72 words
The liquid crystal display as defined in claim 15, wherein: the alignment film on one of the opposing surfaces comprises raised sections, each having tapered faces on both side faces thereof that are inclined with respect to the opposing surface of the corresponding light-transmitting substrate, and a border between the first division of liquid crystal layer and the second division of liquid crystal layer is placed on each of the raised sections.
Claim 23
Dependent Claim
47 words
The liquid crystal display as defined in claim 21, wherein: a height of the raised section is set in a range of 500 to 5000 Å and a width of an upper face of the raised section is set in a range of 5 to 50 μm.
Claim 24
Dependent Claim
38 words
The liquid crystal display as defined in claim 22, wherein said each of the raised sections is formed on each of storage-capacitor electrodes that are formed on the corresponding light-transmitting substrate so as to form a storage capacitor.
Claim 25
Dependent Claim
71 words
The liquid crystal display as defined in claim 15, wherein: the alignment film on one of the opposing surfaces comprises recessed sections, each having tapered faces on-both side faces thereof that are inclined with respect to the opposing surface of the corresponding light-transmitting substrate, and a border between the first division of liquid crystal layer and the second division of liquid crystal layer is placed on each of the recessed sections.
Claim 26
Dependent Claim
47 words
The liquid crystal display as defined in claim 24, wherein: a depth of the recessed section is set in a range of 500 to 5000 Å and a width of A bottom face of the recessed section is set in a range of 5 to 50 μm.
Claim 27
Dependent Claim
56 words
The liquid crystal display as defined in claim 15, wherein: a color filter is formed on either of the pair of the light-transmitting substrates, and the ratio of sizes of the first division of liquid crystal layer and the second division of liquid crystal layer is determined in accordance with respective colors of the color filter.
Claim 28
Dependent Claim
44 words
The liquid crystal display as defined in claim 26, wherein the ratio is set so that light rays which have passed through the first division of liquid crystal layer and the second division of liquid crystal layer have additive complementary colors to each other.
Claim 29
Dependent Claim
42 words
The liquid crystal display as defined in claim 1, wherein the optical phase-difference plate is formed by providing a support base made of a transparent organic polymeric material, and oblique-orienting discotheque liquid crystal onto the support base so as to be crosslinked.
Claim 30
Dependent Claim
42 words
The liquid crystal display as defined in claim 1, wherein the optical phase-difference plate is formed by providing a support base made of a transparent organic polymeric material, and hybrid-orienting discotheque liquid crystal onto the support base so as to be crosslinked.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-11-30 | 2002-06-01 | 2002-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-30 | 2006-06-01 | 2006-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-30 | 2010-06-01 | 2010-12-01 | $7700.00 | Window Closed / Lapsed |