US5479280A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Active matrix for liquid crystal displays having two switching means and discharging means per pixel
Assignee: LG Electronics Inc
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Filing: 1993-12-15
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Granted: 1995-12-26
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Expires: 2013-12-15
Abstract
Abstract An active matrix for liquid crystal displays having a plurality of picture elements, a plurality of address buses to which an address signal having a high signal level and a low steady state signal level is applied, and a plurality of data buses orthogonal to the address buses. Each picture element includes at least one display electrode device; a first switching device coupled between the display electrode device and a first respective one of the address buses and a respective one of the data buses; and a second switching device coupled between the display electrode device and a second respective one of the address buses and the respective data bus. The second switching device includes a device for preventing the display electrode from discharging whereby a substantially same voltage is maintained at the display electrode during the time when the address signal changes from the high level to the low level.
Inventors
- 👤 Boris I. Kazurov
- 👤 Oleg F. Ogurtsov
- 👤 Gennadi Y. Krasnikov
- 👤 Boris P. Chernorotov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:22
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3648; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/136; G02F1/1362; G02F1/136286; G02F1/1368; G02F1/13624; G09G2300/00; G09G2300/08; G09G2300/0809; G09G2320/00; G09G2320/02; G09G2320/0219; G09G2330/00; G09G2330/08
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
175 words
An active matrix for liquid crystal displays having a plurality of picture elements arranged in the matrix, a plurality of address buses arranged in rows of the matrix and supplied with an address signal having a high signal level and a low steady state signal level, and a plurality of data buses orthogonal to the address buses, each of said picture elements comprising: at least one display electrode means; a first switching means coupled between said display electrode means and a first respective one of the address buses and a respective one of the data buses; a second switching means coupled between said display electrode means and a second respective one of the address buses and said respective data bus; and means, coupled between said second switching means and in series with said display electrode means, for preventing said display electrode means from discharging and maintaining a substantially constant voltage at the display electrode means during the time when the address signal changes from the high signal level to the low steady state signal level.
Claim 2
Dependent Claim
175 words
An active matrix for liquid crystal displays having a plurality of picture elements arranged in the matrix, a plurality of address buses arranged in rows of the matrix and supplied with an address signal having a high signal level and a low steady state signal level, and a plurality of data buses orthogonal to the address buses, each of said picture elements comprising: at least one display electrode means; a first switching means coupled between said display electrode means and a first respective one of the address buses and a respective one of the data buses; a second switching means coupled between said display electrode means and a second respective one of the address buses and said respective data bus; and means, coupled between said second switching means and in series with said display electrode means, for preventing said display electrode means from discharging and maintaining a substantially constant voltage at the display electrode means during the time when the address signal changes from the high signal level to the low steady state signal level.
Claim 3
Dependent Claim
13 words
The active matrix of claim 1, wherein said preventing means includes a diode.
Claim 4
Dependent Claim
13 words
The active matrix of claim 2, wherein said diode includes a Schottky diode.
Claim 5
Dependent Claim
24 words
The active matrix of claim 2, wherein said diode includes a MIS (Metal Insulator Semiconductor) transistor having its drain gate connected to one another.
Claim 6
Dependent Claim
91 words
The active matrix of claim 2, wherein said second switching element includes a thin film transistor having a drain coupled to said respective data bus, a gate to said second address bus, and a source to one end of said diode, and wherein another end of said diode is connected to the display electrode in a manner for preventing said display electrode from discharging whereby a substantially constant voltage is maintained at the display electrode during the time when the address signal changes from the high level to the low level.
Claim 7
Dependent Claim
91 words
The active matrix of claim 2, wherein said second switching element includes a thin film transistor having a source coupled to said respective data bus, a gate to said second address bus, and a drain to one end of said diode, and wherein another end of said diode is connected to the display electrode in a manner for preventing said display electrode from discharging whereby a substantially constant voltage is maintained at the display electrode during the time when the address signal changes from the high level to the low level.
Claim 8
Dependent Claim
20 words
The active matrix of claim 5 or 6, wherein said thin film transistor includes a MIS (Metal Insulator Semiconductor) transistor.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1998-12-25 | 1999-06-26 | 1999-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-12-25 | 2003-06-26 | 2003-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-12-25 | 2007-06-26 | 2007-12-26 | $7700.00 | Window Closed / Lapsed |