US4679043A
Expired / Lapsed
US
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Method of driving liquid crystal matrix display
Assignee: Citizen Watch Co Ltd
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Filing: 1983-12-27
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Granted: 1987-07-07
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Expires: 2003-12-27
Abstract
Abstract A drive method for a liquid crystal matrix display panel whereby the display is driven as two or more separate regions, with each region being successively driven by row and column drive signals to display video data in a row-by-row manner during a drive phase while the remaining regions operate in a rest phase in which a potential substantially equal to zero is applied across the display elements of these other regions. The effective number of row electrodes to which sequential scanning signal pulses are applied, which determines the level of contrast obtainable with such a display panel when the number of display elements is large, is made equal to the number of row electrodes of each of these regions, so that a sufficiently high number of elements for high-resolution television display is attainable with a simple display panel and peripheral circuit configuration.
Inventors
- 👤 Shigeru Morokawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:44
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3622; G09G3/3644
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
296 words
A method of driving a liquid crystal display matrix display panel having a plurality of mutually independent row electrodes coupled to receive periodically generated timing signal pulses, applied successively to all of said row electrodes during each of successively occurring scanning field periods, and a plurality of column electrodes coupled to column electrode drive circuit means for receiving in synchronism with said timing signal pulses drive signals representing display data, with a plurality of liquid crystal display elements being formed at intersections of said row electrodes and column electrodes, said column electrodes being divided into at least a first set of column electrodes for driving liquid crystal display elements in a first region of said display panel in conjunction with a first set of said row electrodes and a second set of column electrodes for driving liquid crystal display elements in a second region of said display panel in conjunction with a second set of said row electrodes, said first and second sets of column electrodes being mutually independent, said column electrode drive means being divided into mutually independent first and second column electrode drive means for driving said first and second sets of column electrodes respectively, and wherein each of said regions operates alternately in a drive phase, during a specific portion of said scanning field period, in which drive signals are applied to the column electrodes thereof and timing signal pulses are applied sequentially to select the row electrodes thereof, and a rest phase, during another portion of said scanning field period, in which a potential substantially equal to zero is applied across all of the display elements thereof, and wherein while one of said regions is operating in said rest phase the other one of said regions is operating in said drive phase.
Claim 2
Independent Claim
296 words
A method of driving a liquid crystal display matrix display panel having a plurality of mutually independent row electrodes coupled to receive periodically generated timing signal pulses, applied successively to all of said row electrodes during each of successively occurring scanning field periods, and a plurality of column electrodes coupled to column electrode drive circuit means for receiving in synchronism with said timing signal pulses drive signals representing display data, with a plurality of liquid crystal display elements being formed at intersections of said row electrodes and column electrodes, said column electrodes being divided into at least a first set of column electrodes for driving liquid crystal display elements in a first region of said display panel in conjunction with a first set of said row electrodes and a second set of column electrodes for driving liquid crystal display elements in a second region of said display panel in conjunction with a second set of said row electrodes, said first and second sets of column electrodes being mutually independent, said column electrode drive means being divided into mutually independent first and second column electrode drive means for driving said first and second sets of column electrodes respectively, and wherein each of said regions operates alternately in a drive phase, during a specific portion of said scanning field period, in which drive signals are applied to the column electrodes thereof and timing signal pulses are applied sequentially to select the row electrodes thereof, and a rest phase, during another portion of said scanning field period, in which a potential substantially equal to zero is applied across all of the display elements thereof, and wherein while one of said regions is operating in said rest phase the other one of said regions is operating in said drive phase.
Claim 3
Dependent Claim
43 words
A drive method according to claim 1, in which said potential substantially equal to zero in said rest phase is established by setting the potentials of the column electrodes and row electrodes of a region operating in said rest phase to identical values.
Claim 4
Dependent Claim
45 words
A drive method according to claim 1, in which said potential substantially equal to zero in said rest phase is is established by employing switching elements to apply a short-circuit between the column electrodes and row electrodes of a region operating in said rest phase.
Claim 5
Dependent Claim
42 words
A drive method according to claim 1, in which said timing signal pulses applied to drive said row electrodes vary between at least three different potentials and in which said drive signals applied to said column electrodes vary between two different potentials.
Claim 6
Dependent Claim
57 words
A drive method according to claim 1, in which said timing signal pulses applied to drive said row electrodes and said drive signals applied to said column electrodes each comprise trains of pulses of alternating polarity, with the pulse train of said timing signal pulses being identical in polarity to that of said column electrode drive signals.
Claim 7
Dependent Claim
31 words
A drive method according to claim 1, in which said drive circuit means of said row electrodes and column electrodes comprise complementary field-effect transistor switches formed in a monolithic integrated circuit.
Claim 8
Dependent Claim
17 words
A drive method according to claim 6, in which said monolithic integrated circuit is of insulated-substrate configuration.
Claim 9
Dependent Claim
17 words
A drive method according to claim 6, in which said monolithic integrated circuit comprises a silicon-on-saphire substrate.
Claim 10
Dependent Claim
56 words
A drive method according to claim 1, in which multiplexed driving of said row electrodes and column electrodes is employed, with each column of said display elements being driven by a plurality of sets of column electrodes, and with each of said row electrodes serving to drive a corresponding plurality of rows of said display elements.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-06 | 1991-01-05 | 1991-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-06 | 1995-01-05 | 1995-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-06 | 1999-01-05 | 1999-07-07 | $7700.00 | Window Closed / Lapsed |