US3645604A
Expired / Lapsed
US
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Liquid crystal display
Assignee: AT&T Inc
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Filing: 1970-08-10
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Granted: 1972-02-29
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Expires: 1990-08-10
Abstract
Abstract An improved liquid crystal display is disclosed in which a multilevel gray scale is provided by stacking a plurality of conventional liquid crystal display devices and addressing the respective display devices in selected combinations. Successive display devices in the stack are of different thicknesses or of different material composition, such that with like magnitude signals applied thereto, each display scatters light by a different predetermined amount. A single addressing circuit is employed in common for all of the display devices, with respective bits of a multibit gray scale codeword determining the energization of the individual display devices in the stack.
Inventors
- 👤 Dinh-Tuan Ngo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:48
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1347; G02F1/13476; G09; G09F; G09F9/00; G09F9/46; G02F2203/00; G02F2203/30
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
54 words
A display comprising a stack of liquid crystal display devices, and gray scale means including fixed magnitude signal means for selectively energizing individual ones of said display devices to cause said individual devices to scatter light, each of said devices providing different predetermined levels of light scattering when energized by said gray scale means.
Claim 2
Dependent Claim
54 words
A display comprising a stack of liquid crystal display devices, and gray scale means including fixed magnitude signal means for selectively energizing individual ones of said display devices to cause said individual devices to scatter light, each of said devices providing different predetermined levels of light scattering when energized by said gray scale means.
Claim 3
Dependent Claim
43 words
A display according to claim 1 wherein said display devices each comprise first and second sets of conductors having liquid crystal material disposed therebetween, said liquid crystal material of each of said display devices being of different predetermined thickness relative to one another.
Claim 4
Dependent Claim
17 words
A display according to claim 1 wherein each of said display devices comprise different liquid crystal material.
Claim 5
Dependent Claim
28 words
A display according to claim 1 wherein said gray scale means includes means for applying a like magnitude signal in common to selected ones of said display devices.
Claim 6
Dependent Claim
52 words
A display device comprising a plurality of liquid crystal display levels, each of said display levels being of different predetermined thickness relative to one another, and means for selectively exciting individual ones of said display levels with a common signal for causing said individual ones of said display levels to scatter light.
Claim 7
Dependent Claim
52 words
A display device comprising a plurality of liquid crystal display levels, each of said display levels being of different predetermined thickness relative to one another, and means for selectively exciting individual ones of said display levels with a common signal for causing said individual ones of said display levels to scatter light.
Claim 8
Dependent Claim
50 words
A display comprising a plurality of layers of liquid crystal material, a plurality of sets of conductors interleaved with said layers and arranged so as to define respective arrays of cross-point cells with each of said layers, and means for applying predetermined magnitude signals to individual ones of said cells.
Claim 9
Dependent Claim
50 words
A display comprising a plurality of layers of liquid crystal material, a plurality of sets of conductors interleaved with said layers and arranged so as to define respective arrays of cross-point cells with each of said layers, and means for applying predetermined magnitude signals to individual ones of said cells.
Claim 10
Dependent Claim
46 words
A display according to claim 6 wherein n arrays of said cross-point cells are defined by n+1 sets of conductors interleaved with said layers of liquid crystal material, the cells of each array being substantially in registration with corresponding cells of other ones of said arrays.
Claim 11
Dependent Claim
44 words
A display according to claim 7 wherein each of said layers comprises a layer of dielectric material having an array of holes disposed therein containing liquid crystal material, said conductors being arranged so as to define respective cross-point cells with each of said holes.
Claim 12
Dependent Claim
65 words
A display comprising a stack of display devices individually including first and second conductors separated by liquid crystal material, said liquid crystal material of each of said display devices being of different predetermined thickness relative to said liquid crystal material of the other of said devices, such that with like magnitude electrical fields applied thereto each said device exhibits different predetermined degrees of light scattering.
Claim 13
Dependent Claim
65 words
A display comprising a stack of display devices individually including first and second conductors separated by liquid crystal material, said liquid crystal material of each of said display devices being of different predetermined thickness relative to said liquid crystal material of the other of said devices, such that with like magnitude electrical fields applied thereto each said device exhibits different predetermined degrees of light scattering.
Claim 14
Dependent Claim
51 words
A display comprising a stack of n display cells arranged substantially in registration with one another, each of said cells including a pair of conductors with liquid crystal material disposed therebetween, sucH that a 2n level gray scale is provided by energizing selected combinations of said cells with fixed magnitude signals.
Claim 15
Dependent Claim
51 words
A display comprising a stack of n display cells arranged substantially in registration with one another, each of said cells including a pair of conductors with liquid crystal material disposed therebetween, sucH that a 2n level gray scale is provided by energizing selected combinations of said cells with fixed magnitude signals.
Claim 16
Dependent Claim
56 words
A display according to claim 10 wherein said liquid crystal material of each of said cells is respectively of different predetermined thickness, such that with like magnitude signals applied thereto each of said cells in said stack provides a different predetermined level of light scattering, said different levels differing from one another by substantially like factors.
Claim 17
Dependent Claim
53 words
A display according to claim 10 wherein said liquid crystal material is of different composition for each of said cells in said stack, such that with like magnitude signals applied thereto each said cell provides a different predetermined level of light scattering, said different levels differing from one another by substantially like factors.
References Cited (Backward Citations)
US3499112A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |