US4746197A
Expired / Lapsed
US
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Driving circuit for liquid crystal display device
Assignee: Hitachi Ltd
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Filing: 1986-07-24
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Granted: 1988-05-24
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Expires: 2006-07-24
Abstract
Abstract A liquid crystal display device comprises: a liquid crystal module including liquid crystal display panel having a plurality of liquid crystal picture elements arranged in a matrix form, and driving circuits for applying driving signals to signal electrodes and to scanning electrodes of the liquid crystal display panel, respectively; a control circuit for controlling operations of the liquid crystal module; and a means for inverting polarity of a voltage to be applied to a liquid crystal layer by generating a control signal M' having a period mτ which signal inverts the polarity of the voltage to be applied to the liquid crystal layer whenever a clock signal having a period τ is counted a predetermined number m/2. However, if a period of a frame frequency is nτ and an arbitrary integer is L, (1) m is set to be 2n/(2L-1), or (2) m is set to be n/L and the control signal M' is inverted per said frame period nτ, or (3) m is set to satisfy L-1/2<n/m<L, or (4) m is set to satisfy L-1<n/m<L-1/2 and the control signal M' is inverted per the frame period nτ. Furthermore, if the least common multiple of 2n and m is H, values of m are set so that both H/(2n) and H/m are not simultaneously odd numbers.
Inventors
- 👤 Shyusuke Endo
- 👤 Toshiyuki Sakuma
- 👤 Toshimitsu Matsudo
- 👤 Kiyoshige Kinugawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 01:38
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3614
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
220 words
A liquid crystal display device comprising: a liquid crystal module including a liquid crystal display panel having a plurality of liquid crystal picture elements arranged in a matrix form, and driving circuits for applying driving signals to signal electrodes and to scanning electrodes of said liquid crystal display panel, respectively; a control circuit for controlling operations of said liquid crystal module; and a means for inverting polarity of a voltage that is to be applied to a liquid crystal layer by generating a control signal M' having a period mτ which signal inverts said polarity of said voltage to be applied to said liquid crystal layer whenever a clock signal having a period τ is counted a predetermined number m/2. wherein if a period of a frame frequency is nτ and an arbitrary integer is L, (1) m is set to be 2n/(2L-1), or (2) m is set to be n/L and said control signal M' is inverted per said frame period nτ, or (3) m is set to satisfy L-1/2<n/m<L, or (4) m is set to satisfy L-1<n/m<L-1/2 and said control signal M' is inverted per said frame period nτ, and furthermore if the least common multiple of 2n and m be H, values of m are set so that both H/(2n) and H/m are not simultaneously odd numbers.
Claim 2
Dependent Claim
220 words
A liquid crystal display device comprising: a liquid crystal module including a liquid crystal display panel having a plurality of liquid crystal picture elements arranged in a matrix form, and driving circuits for applying driving signals to signal electrodes and to scanning electrodes of said liquid crystal display panel, respectively; a control circuit for controlling operations of said liquid crystal module; and a means for inverting polarity of a voltage that is to be applied to a liquid crystal layer by generating a control signal M' having a period mτ which signal inverts said polarity of said voltage to be applied to said liquid crystal layer whenever a clock signal having a period τ is counted a predetermined number m/2. wherein if a period of a frame frequency is nτ and an arbitrary integer is L, (1) m is set to be 2n/(2L-1), or (2) m is set to be n/L and said control signal M' is inverted per said frame period nτ, or (3) m is set to satisfy L-1/2<n/m<L, or (4) m is set to satisfy L-1<n/m<L-1/2 and said control signal M' is inverted per said frame period nτ, and furthermore if the least common multiple of 2n and m be H, values of m are set so that both H/(2n) and H/m are not simultaneously odd numbers.
Claim 3
Dependent Claim
25 words
A liquid crystal display device as set forth in claim 1, wherein a period TM' of said control signal M' fulfills the following inequality; 2.0≦nτ/τM'≦6.0.
Claim 4
Dependent Claim
22 words
A liquid crystal display device as set forth in claim 2, wherein Nτ is not an integral multiple of τ M' .
Claim 5
Dependent Claim
23 words
A liquid crystal display device as set forth in claim 1, wherein said control signal M' does not synchronize with said frame frequency.
Claim 6
Dependent Claim
40 words
A liquid crystal display device as set forth in claim 4, wherein scanning electrodes where polarity of a voltage to be applied to said liquid crystal elements is inverted differ by less than ten scanning electrodes from frame to frame.
Claim 7
Dependent Claim
25 words
A liquid crystal display device as set forth in claim 1, wherein said clock signal is a latch signal for latching information data for display.
Claim 8
Dependent Claim
226 words
A liquid crystal display device comprising: a liquid crystal module including a liquid crystal display panel divided into a plurality of blocks having a plurality of liquid crystal picture elements arranged in a matrix form, and driving circuits for applying driving signals to signal electrodes and to scanning electrodes of said liquid crystal display panel, respectively; a control circuit for controlling operations of said liquid crystal module; and a means for inverting polarity of a voltage that is to be applied to a liquid crystal layer by generating a control signal M' having a period mτ which signal inverts said polarity of said voltage to be applied to said liquid crystal layer whenever a clock signal having a period τ is counted a predetermined number m/2, wherein if a period of a frame frequency is nτ and an arbitrary integer is L, (1) m is set to be 2n/(2L-1), or (2) m is set to be n/L and said control signal M' is inverted per said frame period nτ, or (3) m is set to satisfy L-1/2<n/m<L, or (4) m is set to satisfy L-1<n/m<L-1/2 and said control signal M' is inverted per said frame period nτ, and furthermore if the least common multiple of 2n and m be H, values of m are set so that both H/(2n) and H/m are not simultaneously odd numbers.
Claim 9
Dependent Claim
226 words
A liquid crystal display device comprising: a liquid crystal module including a liquid crystal display panel divided into a plurality of blocks having a plurality of liquid crystal picture elements arranged in a matrix form, and driving circuits for applying driving signals to signal electrodes and to scanning electrodes of said liquid crystal display panel, respectively; a control circuit for controlling operations of said liquid crystal module; and a means for inverting polarity of a voltage that is to be applied to a liquid crystal layer by generating a control signal M' having a period mτ which signal inverts said polarity of said voltage to be applied to said liquid crystal layer whenever a clock signal having a period τ is counted a predetermined number m/2, wherein if a period of a frame frequency is nτ and an arbitrary integer is L, (1) m is set to be 2n/(2L-1), or (2) m is set to be n/L and said control signal M' is inverted per said frame period nτ, or (3) m is set to satisfy L-1/2<n/m<L, or (4) m is set to satisfy L-1<n/m<L-1/2 and said control signal M' is inverted per said frame period nτ, and furthermore if the least common multiple of 2n and m be H, values of m are set so that both H/(2n) and H/m are not simultaneously odd numbers.
Claim 10
Dependent Claim
26 words
A liquid crystal display device as set forth in claim 7, wherein a period τ M' of said control signal M' satisfies the following inequality; 2.0≦nτ/τM'≦6.0.
Claim 11
Dependent Claim
22 words
a liquid crystal display device as set forth in claim 8, wherein nτ is not an integral multiple of τ M' .
Claim 12
Dependent Claim
23 words
A liquid crystal display device as set forth in claim 7, wherein said control signal M' does not synchronize with a frame frequency.
Claim 13
Dependent Claim
40 words
A liquid crystal display device as set forth in claim 10, wherein scanning electrodes where polarity of a voltage to be applied to said liquid crystal elements is inverted differ by less than ten scanning electrodes from frame to frame.
Claim 14
Dependent Claim
25 words
A liquid crystal display device as set forth in claim 7, wherein said clock signal is a latch signal for latching information data for display.
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) | 1991-05-24 | 1991-11-23 | 1992-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-24 | 1995-11-23 | 1996-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-24 | 1999-11-23 | 2000-05-24 | $7700.00 | Window Closed / Lapsed |