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US 6,549,185 B1Granted
Display apparatus and method for driving a liquid crystal display
AssigneeMinola Co., Ltd.
InventorTakuji Hatano
Life of this patent
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Abstract
A display apparatus includes a liquid crystal display which has a pair of plates each provided with an electrode and a liquid crystal layer retained between the plates, and a driver which is connected to said liquid crystal display for applying a voltage pulse to the electrodes. The driver applies a first voltage pulse for changing the state of the liquid crystal layer, and further, after elapsing of a predetermined time, applies a second voltage pulse for setting the liquid crystal layer to a stable state.
Claims46
A display apparatus comprising:
- a liquid crystal display having a pair of plates with electrodes and a liquid crystal layer retained between said plates, said liquid crystal layer including cholesteric liquid crystal exhibiting a cholesteric phase;
- and
- a driver connected to said liquid crystal display to apply voltage pulses to said electrodes, said driver applying a first voltage pulse and after a predetermined lapse of time further applying a second voltage pulse in according with desired gradation, the first voltage pulse resetting said cholesteric liquid crystal by temporally setting molecules thereof to a homeotropic arrangement, the second voltage pulse setting said cholesteric liquid crystal to a stable state corresponding to the desired gradiation,
- wherein said cholesteric liquid crystal remains in said stable state after application of said second voltage pulse in absence of any further voltage application.
1 more element
A display apparatus comprising:
- a liquid crystal display having a pair of plates with electrodes and a liquid crystal layer retained between said plates, said liquid crystal layer including a cholesteric liquid crystal exhibiting a cholesteric phase;
- a driver connected to said liquid crystal display for applying a first voltage pulse and a second voltage pulse following said first voltage pulse,
- wherein the first voltage pulse resets said cholesteric liquid crystal by temporally setting molecules thereof to a homeotropic arrangement, and the second voltage pulse sets said cholesteric liquid crystal to a stable state;
- and
- a controller connected to said driver to adjust a width of said second voltage pulse in accordance with desired gradation,
- wherein said cholesteric liquid crystal remains in said stable state after application of said second voltage pulse in absence of any further voltage application.
3 more elements
A display apparatus comprising:
- a liquid crystal display having a pair of plates with electrode and a liquid crystal layer retained between said plates, said liquid crystal layer including a cholesteric liquid crystal exhibiting a cholesteric phase;
- a driver connected to said liquid crystal display for applying a first voltage pulse and a plurality of second voltage pulses following said first voltage pulse,
- wherein the first voltage pulse resets said cholesteric liquid crystal by temporally setting molecules thereof to a homeotropic arrangement, and the second voltage pulses are set said cholesteric liquid crystal to a stable state;
- and
- a controller connected to said driver to adjust levels of said second voltage pulses in accordance with desired gradation,
- wherein said cholesteric liquid crystal remains in said stable state after application of said second voltage pulse in absence of any further voltage application.
3 more elements
A method of driving a liquid crystal display having a pair of plates with electrodes and a liquid crystal layer retained between said plates, said liquid crystal layer including a cholesteric liquid crystal exhibiting a cholesteric phase, said method comprising the steps of:
- applying a first voltage pulse to said electrodes of said liquid crystal display to temporally set molecules of said cholesteric liquid crystal to a homeotropic arrangement thus resetting said cholesteric liquid crystal;
- and
- applying, upon elapsing of a predetermined time after applying said first voltage pulse, a second voltage pulse that has a waveform corresponding to a desired gradation to said liquid crystal display to set said cholesteric liquid crystal to a stable state corresponding to the desired gradiation in absence of any further voltage application.
A method of driving a liquid crystal display having a first electrode, a second electrode, and a liquid crystal layer retained between said first and second electrodes, said liquid crystal layer including a liquid crystal exhibiting a cholesteric phase, said method comprising the steps of:
- (a) applying a first voltage pulse to said first electrode;
- (b) applying, upon elapsing of a predetermined time after applying said first voltage pulse, a second voltage pulse to said first electrode;
- and
- (c) applying a third voltage pulse to said second electrode with controlling an application timing relative to the step (b) in accordance with desired gradation, wherein the step (a) temporally sets molecules of said liquid crystal to a homeotropic arrangement to reset said liquid crystal, and wherein said steps (b) and (c) set said liquid crystal to a stable state of the desired gradation,
- wherein said cholesteric liquid crystal remains in said stable state after application of said second voltage pulse and said third voltage pulse in absence of any further voltage application.
2 more elements
A display apparatus comprising:
- a first electrode;
- a second electrode;
- a liquid crystal layer retained between said first and second electrodes, said liquid crystal layer including a liquid crystal exhibiting a cholesteric phase;
- and
- a controller connected with said first electrode and second electrode, said controller applying, to said first electrode, a first voltage pulse and a second voltage pulse upon elapsing of a predetermined time after applying said first voltage pulse, and said controller applying, to said second electrode, a third voltage pulse with controlling an application timing relative to the second voltage pulse in accordance with desired gradation,
- wherein the first voltage pulse temporally sets molecules of said liquid crystal to a homeotropic arrangement to reset said liquid crystal, and wherein said second voltage pulse and said third voltage pulse set said liquid crystal to a stable state of the desired gradation,
- wherein said cholesteric liquid crystal stays in said stable state after application of said second voltage pulse and said third voltage pulse in absence of any further voltage application.
4 more elements
A method of driving a liquid crystal display having a liquid crystal layer between a pair of substrates, said liquid crystal including a liquid crystal exhibiting a cholesteric phase, said method comprising the steps of:
- (a) applying a first voltage pulse to said liquid crystal layer;
- and
- (b) applying, upon elapsing of a waiting term after applying said first voltage pulse, a second voltage pulse to said liquid crystal layer with controlling a waveform thereof in accordance with a desired gradiation,
- wherein the step (a) temporally sets molecules of said liquid crystal to a homeotropic arrangement to reset said liquid crystal, and wherein step (b) tempts said liquid crystal to a stable state of the desired gradation,
- wherein said liquid crystal is capable of remaining in said stable state after application of said second electrical field in absence of any further electrical field application.
2 more elements
A display apparatus comprising:
- a liquid crystal display including a pair of substrates and a liquid crystal layer retained between said pair of substrates, said liquid crystal layer including a liquid crystal exhibiting a cholesteric phase;
- and
- a controller connected with said liquid crystal display, said controller applying a first voltage pulse to said liquid crystal layer, said controller further applying, upon elapsing of a waiting term after applying said first voltage pulse, a second voltage pulse with controlling a waveform thereof in accordance with desired gradation,
- wherein the first voltage pulse temporarily sets molecules of said liquid crystal to a homeotripic arrangement to reset said liquid crystal, and wherein said second voltage pulse tempts said liquid crystal to a stable state of the desired gradation,
- wherein said liquid crystal is set in said stable state after application of said second voltage pulse, and
- wherein said liquid crystal is capable of remaining in said stable state after being set in said stable in absence of any further application.
3 more elements
A display apparatus comprising:
- a liquid crystal display including a pair of substrates and a liquid crystal layer retained between said pair of substrates, said liquid crystal layer including a liquid crystal exhibiting a cholesteric phase;
- and
- a controller connected with said liquid crystal display, said controller applying, in a first time period, a first voltage pulse to said liquid crystal layer, said controller further applying, in a second time period that is subsequent to the first time period, a second voltage pulse with controlling a waveform thereof in accordance with a desired level of an optical scale that comprises at least two levels,
- wherein the first voltage pulse is for resetting said liquid crystal to a transparent state, and wherein said second voltage pulse is for setting said liquid crystal to a stable state that corresponds to the desired level,
- wherein said liquid crystal is set in said stable state after the application of said second voltage pulse,
- wherein said liquid crystal is capable of remaining on said stable state after the set in absence of any further voltage application.
3 more elements
Dependencies are inferred from the claim text.