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US5155613A Expired / Lapsed US ⏱️ 0.0 years remaining

Driving circuit of liquid crystal display which has delay means

Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1991-08-23
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Granted: 1992-10-13
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Expires: 2011-08-23
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Abstract

Abstract A driving circuit for liquid crystal display is disclosed and includes a circuit for outputting driving signals to a ferroelectric liquid crystal display in order to construct visual information in the display and a voltage source for supplying a predetermined voltage such that when the display system is switched off the circuit means outputs an erasing signal to the liquid crystal display for erasing all of the visual information displayed in the display and eliminates phantom figures from appearing when the display is reused.

Inventors

  • 👤 Hiroyuki Sakayori

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 21:42
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3696; G09G3/3622; G09G3/3629; G09G2310/00; G09G2310/02; G09G2310/0243; G09G2310/0245

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 107 words
A driving and switching off circuit for a liquid crystal display device having a memory effect and a plurality of pixels, each pixel having the capability of exhibiting two states in accordance with an electric field applied thereto, said circuit comprising: driving means for applying a drive signal to said display device to cause all of said pixels to uniformly exhibit one of said two states; and delay means for providing a delay signal ending subsequent to the application of said drive signal; means responsive to said delay means for switching off said display device subsequent to causing all the pixels to uniformly exhibit said one state.
Claim 2
Dependent Claim 107 words
A driving and switching off circuit for a liquid crystal display device having a memory effect and a plurality of pixels, each pixel having the capability of exhibiting two states in accordance with an electric field applied thereto, said circuit comprising: driving means for applying a drive signal to said display device to cause all of said pixels to uniformly exhibit one of said two states; and delay means for providing a delay signal ending subsequent to the application of said drive signal; means responsive to said delay means for switching off said display device subsequent to causing all the pixels to uniformly exhibit said one state.
Claim 3
Independent Claim 120 words
A method for driving and switching off a liquid crystal display device having a memory effect and a plurality of pixels, each pixel having the capability of exhibiting two states in accordance with an electric field applied thereto, said method comprising the steps of: generating a turn off signal to turn off said display device; applying a drive signal, in response to said turn off signal, to said display device to cause all of said pixels to uniformly exhibit one of said two states; and delaying said turn off signal to provide a delayed turn off signal ending subsequent to the application of said drive signal; thereafter, in response to the delayed turn off signal, switching off said display device.
Claim 4
Independent Claim 120 words
A method for driving and switching off a liquid crystal display device having a memory effect and a plurality of pixels, each pixel having the capability of exhibiting two states in accordance with an electric field applied thereto, said method comprising the steps of: generating a turn off signal to turn off said display device; applying a drive signal, in response to said turn off signal, to said display device to cause all of said pixels to uniformly exhibit one of said two states; and delaying said turn off signal to provide a delayed turn off signal ending subsequent to the application of said drive signal; thereafter, in response to the delayed turn off signal, switching off said display device.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-10-13 1996-04-13 1996-10-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-10-13 2000-04-13 2000-10-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-10-13 2004-04-13 2004-10-13 $7700.00 Window Closed / Lapsed

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