CN100439981C - Liquid crystal display element and its drive method - Google Patents
Liquid crystal display element and its drive method Download PDFInfo
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Abstract
This invention provides a driving method for preventing display unevenness from being caused even if rewriting speed is made high. The driving method has a reset period wherein all pixels are made to be in a planar state by applying a reset signal to a liquid crystal which constitutes all pixels, a rewriting period wherein the display state of the liquid crystal which constitutes all pixels is rewritten by repeating rewriting operations for applying a selection signal to the liquid crystal which constitutes pixels on a common selection electrodes to select a display state and applying a non-selection signal to the liquid crystal which constitutes pixels on a non-selection signal and an entire surface collective non-selection state maintaining period wherein all pixels are maintained in a non-selection state by applying the non-selection signal to the liquid crystal which constitutes all pixels.
Description
Technical field
The present invention relates to the driving method of liquid crystal display cells, particularly relate to from a plurality of common electrodes of under state opposite one another, intersecting and a plurality of segmented electrode driving method to the cholesteric crystal display element of liquid crystal layer input voltage waveform.
Background technology
Open the spy and to disclose the method that drives the liquid crystal display cells that demonstrates the cholesterol phase in the flat 11-326871 communique with Memorability.The ordered state that this method is interelectrode liquid crystal applied voltages that common electrode and segmented electrode are intersected, make liquid crystal becomes the driving method of focal circle taper attitude when resetting.Such driving method is called focal circle bores (FCR) method that resets.
Have in this focal circle awl repositioning: make whole pixels become the reseting period of focal circle taper attitude; By successively to apply during the selection of selecting signal voltage to the common electrode of footline from the 1st row and apply the keeping of non-select signal voltage during during the rewriting that constitutes; And during keeping thereafter whole pixels applied the demonstration that shows the show state of keeping signal.
According to this focal circle awl repositioning, have following interesting feature: the characteristic shape of pulse voltage-visual sense reflectivity Characteristics (roughly S font) does not change (can not change shape) with the size of the time of rewriting, be that the row of the 1st under flat state and the focal circle taper attitude is roughly the same to the reflectivity separately of footline, can obtain constant contrast and show, and in the whole viewing area of panel, can be shown uniformly.
In addition, open in the flat 11-326871 communique the spy, thus disclose be provided with the reseting period that makes whole pixels become flat state have make whole pixels become flat state reseting period, apply during the selection of selecting signal voltage and apply the non-selection of non-select signal voltage during the driving method of liquid crystal display cells during these 3.And, can carry out gray scale by the pulse voltage that applies the transport zone between flat state and the focal circle taper attitude in having put down in writing during selecting and show.
Because this driving method makes whole pixels become flat state when resetting, so be called the plane resets method.This plane resets method is compared with focal circle awl repositioning, from the ordered state of liquid crystal be difficult to be subjected to interelectrode distance (cell gap) the place display surface integral body big or small irregular or liquid crystal orientation film the surface state in display surface integral body display surface the place irregular influence, shown viewpoint in the manufacturing of such liquid crystal display cells uniformly easily, have the advantage of practical aspect.
There is following problem in above-mentioned focal circle awl repositioning.(1) Fig. 1 is the example of pulse voltage-visual sense reflectivity Characteristics of the focal circle awl repositioning of cholesteric crystal display element.Be to apply the pulse voltage shown in Fig. 2 (selection waveform) between to electrode, studied the result of pulse voltage to the influence of the reflectivity of cholesteric crystal display element in the focal circle awl back that resets.The pulse width t of Fig. 2 is with the length of the selection waveform that common electrode is provided, promptly the rewriting speed of 1 common electrode is relevant.For the meaning of the pulse voltage of understanding Fig. 2, an example of the voltage waveform that common electrode and segmented electrode are applied shown in Figure 3.V0, V1, V2, V3, V4, V5 represent the magnitude of voltage of voltage waveform respectively.The synthetic waveform of the difference of the voltage waveform that applies as the voltage waveform that common electrode is applied and to segmented electrode becomes the voltage waveform that applies between two electrodes to liquid crystal display cells.The pulse voltage of Fig. 2 shows the selection waveform as synthetic waveform.
Fig. 4 represents to select waveform and non-selection waveform to be applied to the sequential of the pulse voltage on the n bar common electrode.
According to Fig. 3 and Fig. 4, carry out following rewriting work: certain common electrode is elected to be shared selection electrode, other common electrode is elected to be shared non-selection electrode, shared selection electrode is applied shared selection signal, simultaneously shared non-selection electrode is applied shared non-select signal, with shared selection signal Synchronization ground segmented electrode is applied data-signal, pixel on the shared selection electrode is applied the selection signal that the difference by shared selection signal and data-signal constitutes select show state, in addition, the liquid crystal that constitutes the pixel on the shared non-selection electrode is applied the non-select signal that the difference by shared non-select signal and data-signal constitutes, thereafter, next common electrode is elected to be shared selection electrode, carry out rewriting work,, rewrite the show state of the liquid crystal that constitutes whole pixels by repeating this rewriting work.
If plan to accelerate rewriting speed, then must improve the pulse voltage of Fig. 2.Driver drives under the situation of liquid crystal display cells using general STN (supertwist is to row), even withstand voltage high driver, its value also is about 45V.Under the pulse voltage smaller or equal to this voltage, the demonstration for the practicality of seeing easily of the reflectivity height that obtains the planar orientation state, high-contrast must be set at the second more than or equal to 3m with pulse width t (during the selection), exists and rewrites slow-footed shortcoming.In addition,, high withstand voltage special-purpose driving IC chip aspect the driving liquid crystal display cells must be arranged, become the main cause of the cost increase of liquid crystal indicator in order to make the special driver that to export high driving voltage.
(2) in addition, if accelerate rewriting speed, then the inclination of the rising of the curve of Fig. 1 becomes slowly, must increase non-selection voltage.If the increase non-selection voltage then promptly enables to obtain the high planar orientation state of reflectivity, because the cause that applies of non-selection voltage thereafter, reflectivity also suffers damage.Even consider such situation, pulse width t also is necessary for the second more than or equal to 3m.
(3) pulse width t is short more, and the curve shown in Fig. 1 is easy more to be changed with temperature.Under the situation of having considered actual liquid crystal display cells, must carry out temperature compensation subtly.
(4) waveform that carries out gray scale demonstration usefulness with the STN driver shown in Figure 5.Selection waveform, non-selection waveform to common electrode output are identical with the waveform shown in Fig. 3, but have added the waveform that gray scale is used on the selection waveform to segmented electrode output.The waveform that gray scale is used is the form of having mixed data waveform X and data waveform Y, utilizes this mixture ratio to carry out the control of the reflectivity of gray scale demonstration.
Show in order on whole of the viewing area of panel, to carry out uniform gray scale, the homogeneity of surface state of homogeneity, the alignment films of the interelectrode distance (cell gap) of panel is become well, is very difficult but keep above-mentioned homogeneity on whole of many large-scale panels such as the pixel count of e-book, Electronic Paper etc.
Fig. 6 is an example of the pulse voltage-visual sense reflectivity Characteristics of the plane resets method of cholesteric crystal display element.Be illustrated in the pulse voltage shown in the after-applied Fig. 2 of plane resets and studied the result of pulse voltage the influence of the reflectivity of cholesteric crystal display element.As mentioned above, the pulse width t of Fig. 2 with to the length of the selection waveform of common electrode output, promptly the rewriting speed of 1 common electrode is relevant.
According to Fig. 6 as can be known, along with accelerating rewriting speed, be difficult to obtain completely (reflectivity is low) focal circle awl orientation.In addition, be difficult to obtain the good demonstration of contrast.In order to eliminate this problem to obtain not having the demonstration of inharmonious sense, the rewriting speed that must make per 1 common electrode is more than or equal to 10m second.
If the Fabrication parameter of the liquid crystal display cells of the kind of liquid crystal material or cell gap or alignment films etc. is definite, then because the reflectivity constant of flat state, mean that the difference of the reflectivity under plane reflection state and the focal circle awl transmissive state reduces so the reflectivity of focal circle taper attitude increases (characteristic bottom rising in Fig. 6) this point, the contrast of display degree reduces.If the difference of reflectivity reduces, then there is the problem that is difficult to realize grey so-called high gray scale technique for displaying how.
On the other hand, in the plane resets method, if the cycle t of pulse voltage that reduces to select signal voltage is to reduce the rewriting time (increasing rewriting speed), then in the liquid crystal display cells of common electrode number big (increase of display pixel number), pixel for the footline that approaches common electrode, as shown in Figure 6, distinguished and had following problems: the characteristic shape of pulse voltage-visual sense reflectivity Characteristics can not be kept and is out of shape, the reflectivity of focal circle taper attitude rises, and is irregular thereby generation shows.
Summary of the invention
Accelerate the driving method that rewriting speed does not produce the irregular liquid crystal display cells of demonstration yet even the object of the present invention is to provide.
Another object of the present invention is to provide the driving method of the gray scale demonstration that can on whole, realize the contrast good homogeneous.
Another purpose of the present invention is to provide the liquid crystal display cells that is suitable for above-mentioned driving method.
The 1st form of the present invention is the driving method of following liquid crystal display cells: in above-mentioned liquid crystal display cells, by the common electrode group that on the surface of glass substrate, is provided with, on the surface of the opposing party's who disposes opposed to each other with above-mentioned glass substrate glass substrate and the direction of the direction quadrature of above-mentioned common electrode group on the sets of segment electrodes that is provided with and be clipped in and demonstrate cholesterol liquid crystal mutually with rectangular formation pixel between above-mentioned common electrode group and the sets of segment electrodes, when above-mentioned pixel not being applied voltage, utilize the Memorability of liquid crystal to keep by flat state, focal circle taper attitude or the show state that state constitutes in the middle of it, for above-mentioned liquid crystal display cells, utilize the difference of the voltage that above-mentioned common electrode and segmented electrode are applied that above-mentioned pixel is applied voltage.
Driving method of the present invention comprises following step:
Whole common electrodes is applied shared reset signal, whole segmented electrodes is applied data reset signal, whole pixels is applied the reset signal that the difference by these signals constitutes, make whole pixels become flat state;
Carry out following rewriting work, promptly, certain common electrode is elected to be shared selection electrode, other common electrode is elected to be shared non-selection electrode, shared selection electrode is applied shared selection signal, simultaneously shared non-selection electrode is applied the 1st shared non-select signal, with shared selection signal Synchronization ground segmented electrode is applied the 1st data-signal, pixel on the shared selection electrode is applied the selection signal that the difference by shared selection signal and the 1st data-signal constitutes select show state, in addition, pixel on the shared non-selection electrode is applied the 1st non-select signal that the difference by the 1st shared non-select signal and the 1st data-signal constitutes,, next common electrode be elected to be shared selection electrode, carry out above-mentioned rewriting work thereafter, by repeating this rewriting work, rewrite the show state of the liquid crystal that constitutes whole pixels; And
Whole common electrodes is applied the 2nd shared non-select signal, whole segmented electrodes is applied the 2nd data-signal, whole pixels is applied the 2nd non-select signal that the difference by these signals constitutes, whole pixels are maintained nonselection mode.
Driving method of the present invention has adopted the rewriting of plane resets method.The rewriting of plane resets method is compared with the rewriting of focal circle awl repositioning, has following advantage: be difficult to be subjected to the influence of the surface state of the interelectrode distance (cell gap) of panel or alignment films, even in the viewing area, how much exist so irregularly, also can obtain uniform gray scale and show.But, if the capacity of display increases, be that common electrode number and segmented electrode number increase, then the display characteristic of reflectivity-apply voltage with the position of common electrode row difference, it is irregular to produce demonstration thus.It is irregular particularly to produce this demonstration when rewriting at a high speed significantly.
In addition, if be decided to be plane resets, then do not need to carry out the tight control of characteristic of the liquid crystal display cells of gap discreteness between the orientation control of liquid crystal and substrate etc.
In addition, according to the present invention, keep step owing to be provided with the non-selection of whole pixels, so no matter for which pixel, display characteristic all is identical, thereby it is irregular to have eliminated demonstration.Thus, can easily obtain having the homogeneity of demonstration, the liquid crystal display cells of high speed rewriting property.
With whole pixels be maintained nonselection mode during (all the non-selections of pixel keep during) be preferably 5～200m second.Under smaller or equal to the 5m situation of second is inadequate.In addition, under more than or equal to the 200m situation of second, influential to rewriting speed.
For example, if common electrode is 320 a display element, then as typical example, available following calculating formula derives the rewriting time.X is during the non-selection of whole pixels is kept.
20m second (during the plane resets: 50Hz, 1 cycle)+2m second (length of shared selection signal waveform) * 320 (500Hz, 320 cycles)+xm second
=20+640+xm second
If x=200xm second, then the rewriting time is 880m second.
If x=500xm second, then the rewriting time is 1160m second.
In practicality, say, require the rewriting time smaller or equal to 1 second, if because x=200 second, then the rewriting time is 0.88 second, so the present invention can realize this point.
Comparatively it is desirable to, above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the maximum voltage of above-mentioned the 2nd non-select signal is greater than 0V, smaller or equal to 2 times of the maximum voltage of above-mentioned the 1st non-select signal.The voltage of the 2nd non-select signal does not just have effect smaller or equal to 0V.In addition, if, then becoming the reflectivity of the pixel of flat state greater than 2 times of the 1st non-select signal, the voltage of the 2nd non-select signal descends.That is, because the reflectivity of the pixel of the pixel of flat state and focal circle taper attitude all descends, so brightness, contrast all descend, this is unfavorable.
Perhaps, comparatively it is desirable to, above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the minimum voltage of above-mentioned the 2nd non-select signal is less than 0V, more than or equal to 2 times of the minimum voltage of above-mentioned the 1st non-select signal.
Perhaps, comparatively it is desirable to, above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the maximum voltage of these each non-select signals is identical, minimum voltage is also identical.If the voltage of the voltage of the 1st non-select signal and the 2nd non-select signal is inequality, then must newly-increased alive switch.Make its voltage identical, can save switch mechanism.
Comparatively it is desirable to, above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the frequency of above-mentioned the 2nd non-select signal is more than or equal to the frequency of above-mentioned the 1st non-select signal, smaller or equal to 5Hz.If the frequency of frequency ratio the 1st non-select signal of the 2nd non-select signal is little,, be undesirable then because current sinking becomes big.Under situation greater than 5Hz, whole lengthenings during the non-selections of pixel (surpass 200m second), rewriting time lengthening.
Comparatively it is desirable to, the selection signal during the rewriting is a pulse voltage, and its 1 cycle is 0.5～5m second.Under the situation of 1 cycle smaller or equal to 0.5m second (more than or equal to 2000Hz) of selecting signal, even be provided with during the non-selection of whole pixels, its effect also is incomplete, becomes the little demonstration of contrast.In addition, if surpass 5m second (200Hz), then owing to the lengthening of time in the rewriting of display pixel integral body, so be unfavorable in practicality.For example in common electrode is 320 display element, be second 5m second * 320=1.6.
Comparatively it is desirable to, the reset signal that makes whole pixels become flat state is decided to be pulse voltage (high pulse voltage) more than or equal to 30V, in during rewriting, will make pixel become the pulse voltage (low pulse voltage) that focal circle awl State Selection signal is decided to be 7～15V, perhaps will make pixel become the pulse voltage (middle pulse voltage) that selection signal that flat state uses is decided to be 16～28V.Moreover, comparatively it is desirable to 2 * (low pulse voltage)-5≤(middle pulse voltage)≤2 * (low pulse voltage).The condition that is suitable for not only keeping high speed rewriting state but also realizing showing uniformly on whole of viewing area is in this scope.
The 2nd form of the present invention is a liquid crystal indicator, the present invention is the cholesteric crystal display device that possesses following part: liquid crystal display cells, by the common electrode group that on the surface of glass substrate, is provided with, on the surface of the opposing party's who disposes opposed to each other with above-mentioned glass substrate glass substrate and the direction of the direction quadrature of above-mentioned common electrode group on the sets of segment electrodes that is provided with and be clipped in and demonstrate cholesterol liquid crystal mutually with rectangular formation pixel between above-mentioned common electrode group and the sets of segment electrodes, when above-mentioned pixel not being applied voltage, utilize the Memorability of liquid crystal to keep by flat state, focal circle taper attitude or the show state that state constitutes in the middle of it; Common driver is exported shared reset signal, shared selection signal and shared non-select signal to above-mentioned common electrode group; Segment drivers is to above-mentioned sets of segment electrodes output data reset signal and data-signal; And controller, control above-mentioned common driver and segment drivers.It is characterized in that: above-mentioned controller is so that above-mentioned common driver and segment drivers utilize above-mentioned driving method that the mode that the pixel of above-mentioned liquid crystal display cells applies voltage is controlled.
For liquid crystal display cells, comparatively it is desirable to, on the electrode group, cover the vertical alignment layer that forms polyimide.
Under the situation of horizontal alignment film, applying the back at voltage needs several seconds to tens seconds time till the visual sense reflectivity becomes steady state value.In addition, carry out gray scale and show that the scope of condition enactment of usefulness is very narrow, be difficult to carry out meticulous gray scale and show.In addition, field angle is narrow.Different therewith, under the situation of vertical alignment layer, there is not such problem.
Comparatively it is desirable to, the distance between above-mentioned common electrode group and the sets of segment electrodes is 3.5 μ m～6 μ m.Under the situation less than 3.5 μ m, because the thickness of liquid crystal layer reduces, the reflection that is caused by Bragg diffraction is inadequate, so the reflectivity of flat state reduces, contrast descends.If surpass 6 μ m, then the gonorrhoeaization that shows under focal circle taper attitude becomes remarkable.In addition, driving voltage can surpass 45V, so for low voltage drive, be unfavorable.
According to the present invention, after rewriting step, utilize the driving method that the non-selection step of whole pixels is set, irregular demonstration can be realized not showing, and then whole gray scale demonstration of going up the contrast good homogeneous can be implemented in.In addition, according to liquid crystal indicator of the present invention, under the situation of carrying out the meticulous demonstration of large tracts of land height,, can realize that also uniform gray scale shows especially even rewrite at short notice.
Description of drawings
Fig. 1 is the figure of an example that the pulse voltage-visual sense reflectivity Characteristics that is obtained by focal circle awl repositioning of cholesteric crystal display element is shown.
Fig. 2 illustrates the figure that selects waveform.
Fig. 3 is the figure that an example of the voltage waveform that common electrode and segmented electrode are applied is shown.
Fig. 4 is the figure that the sequential of selection waveform that n bar common electrode is applied and non-selection waveform is shown.
Fig. 5 illustrates with the STN driver to carry out the figure that gray scale shows the waveform of usefulness.
Fig. 6 is the figure of an example that the pulse voltage-visual sense reflectivity Characteristics that is obtained by the plane resets method of cholesteric crystal display element is shown.
Fig. 7 is the skeleton diagram that the structure of using cholesteric crystal display device of the present invention is shown.
Fig. 8 is the skeleton diagram of cholesteric crystal display element of the present invention.
Fig. 9 illustrates the common electrode row of the liquid crystal display cells that 4 row * 3 are listed as and the figure of the voltage waveform that the segmented electrode row apply.
Figure 10 is the figure that illustrates the synthetic waveform that applies between electrode.
Figure 11 be illustrated in applied select waveform after-applied near the figure of reflectivity of the pixel of time and the 640th common electrode of liquid crystal display cells of the non-selection waveforms of whole pixels.
Figure 12 be illustrated in applied select waveform after-applied near the figure of contrast of the pixel of time and the 640th common electrode of liquid crystal display cells of the non-selection waveforms of whole pixels.
Figure 13 illustrates to have studied the figure that applies the result of the relation of COM No. and focal circle awl reflectivity behind the voltage waveform shown in Figure 10.
Figure 14 is the figure that voltage change-over switch is shown.
Figure 15 is the figure that voltage change-over switch is shown.
Figure 16 is the figure that voltage waveform is shown.
Figure 17 is near the figure of the optical characteristics of the pixel the 640th common electrode of corresponding pulse voltage and liquid crystal display cells during the selection that illustrates with Figure 16.
Figure 18 is the figure that voltage waveform is shown.
Figure 19 is the figure that the result who applies the visual sense reflectivity of having measured the viewing area behind the voltage waveform shown in Figure 18 is shown.
Figure 20 is the figure that voltage waveform is shown.
Figure 21 is the figure that the waveform of the selection signal that gray scale uses is shown.
Embodiment
Embodiments of the invention below are described with reference to the accompanying drawings.
Fig. 7 is the skeleton diagram that the structure of using cholesteric crystal display device of the present invention is shown.The cholesteric crystal display device possesses: a plurality of common electrode COM1, the COM2 that the state opposite one another that is used in intersects down ... and a plurality of segmented electrode SEG1, SEG2 ... cholesteric crystal is carried out the cholesteric crystal display element 10 of matrix driving; And the mechanism that writes that carries out displaying contents with driving method of the present invention.This mechanism is made of common driver 12, segment drivers 14, controller 16 and power supply 18.
The common electrode of cholesteric crystal display element 10 is connected on the lead-out terminal of common driver 12, and segmented electrode is connected on the lead-out terminal of segment drivers 14.The data of supplying with according to slave controller 16, from common driver 12 couples of common electrode COM1, COM2 ... apply voltage, from segment drivers 14 couples of segmented electrode SEG1, SEG2 ... apply voltage.Pixel to liquid crystal display cells 10 applies the poor of these voltages.
Fig. 8 is the skeleton diagram of cholesteric crystal display element 10 of the present invention.In Fig. 8,, can enumerate quartz glass, aluminium oxide silicic acid glass, aluminium oxide pyrex, alkali-free glass, form SiO as substrate 1
2Films etc. prevent the plastic base of the plastic foil of the soda-lime glass of film of basic ion stripping or polyethersulfone, tygon terephthalate etc. or polycarbonate etc.
On substrate 1 by following sequential cascade electrode 2, electrical insulating film 3 and alignment films 4, the electrode that electrode 2 is patterned into a plurality of linearities is made transparency carrier.With the mode of the electrode crossing 2 such transparency carriers of fitting, in the space that separates with the primary seal pad, enclose cholesteric crystal 6 with primary seal pad 5.
At this, as electrode 2, ITO (indium tin oxide) is suitable, but in addition, also can be SnO
2Deng conductive metal oxide or the conductive material of the electroconductive resin of polypyrrole or polyaniline etc. etc.
For electrical insulating film 3, SiO
2, TiO
2Deng insulating material be suitable.Electrical insulating film 3 is provided with in order to prevent interelectrode short circuit, and is not necessarily necessary.
As alignment films 4, use vertical alignment layer.Polyimide resin is suitable, but also can use surface modifier or resin siliceous, fluorine-containing, nitrogenous class.Can enumerate the chemical society of daily output system SE-1211, SE-7511L, RN-1517 or the eastern radar Wu Gaoning silicon system AY43-021 of society etc.
Cholesteric crystal can be to be dispersed in the type that type in the macromolecule matrix or capsule have sealed.The selection wavelength of cholesteric crystal not only can be in the visible light zone, also can be in the infrared light region.
With observe the opposite side of side, can form light absorping film 7.Color about light absorping film 7 is not particularly limited, but preferably black or blueness.
On the face of observing side, cause mis-behave in order to prevent liquid crystal because of ultraviolet ray, can place plastic plate with ultraviolet cutoff function.In addition, also Pasting has the blooming that prevents reflection function, anti-dazzle function.
The liquid crystal display cells of present embodiment is characterised in that and covers the vertical alignment layer that has formed polyimide on the electrode group.Under the situation of vertical alignment layer, following problem not: after voltage waveform applies resemble the horizontal alignment film, till becoming steady state value, outward appearance (reflectivity) needs several seconds to tens seconds time, in addition, carry out gray scale and show that the scope of condition enactment of usefulness is very narrow, be difficult to carry out meticulous gray scale and show that in addition, field angle is narrow.
Clip cholesteric crystal and opposed electrode 2 is common electrode group and sets of segment electrodes, but the distance of these common electrode groups and sets of segment electrodes is preferably 3.5 μ m～6 μ m.This be because, under situation, because the thickness of liquid crystal layer reduces less than 3.5 μ m, the reflection that is caused by Bragg diffraction is inadequate, so the reflectivity of flat state reduces, contrast descends, if surpass 6 μ m, then the gonorrhoeaization that shows under focal circle taper attitude becomes remarkable.
As cholesteric crystal display element 10, but but use has mixed the liquid crystal that the Mei Er society of 0.25g makes the system cholesteric crystal MDA-03-162 of Mei Er society of nematic liquid crystal MDA-02-1174 and 0.75g, has made the cholesteric crystal display element shown in Fig. 8.The thickness of liquid crystal layer is 4.5 μ m.Alignment films among Fig. 8 is a vertical alignment layer.In addition, on the face opposite, carried out blue printing with sightingpiston.
To the actual matrix driving of resulting liquid crystal display cells (common electrode several 640, segmented electrode several 480) imagination, apply the voltage waveform shown in Fig. 9 successively, measured the visual sense reflectivity in the zone of display pixel.Common electrode row and segmented electrode that Fig. 9 shows for simplicity to the liquid crystal display cells of 4 row * 3 row are listed as the voltage waveform that applies.Among the figure, V0, V1, V2, V3, V4, V5 have represented the magnitude of voltage of voltage waveform respectively.
Figure 10 illustrates the example to the synthetic waveform that applies between electrode.During plane resets, whole common electrodes is applied shared reset signal, whole segmented electrodes is applied data reset signal, the liquid crystal that constitutes whole pixels is applied the reset signal that the difference by these signals constitutes, make whole pixels be reset to flat state.
During rewriting, carry out following rewriting work: certain common electrode is elected to be shared selection electrode, other common electrode is elected to be shared non-selection electrode, shared selection electrode is applied shared selection signal, simultaneously shared non-selection electrode is applied the 1st shared non-select signal, with shared selection signal Synchronization ground segmented electrode is applied the 1st data-signal, the liquid crystal of the pixel that constitutes shared selection electrode is applied the selection signal that the difference by shared selection signal and data-signal constitutes select show state, in addition, the liquid crystal that constitutes the pixel on the shared non-selection electrode is applied the 1st non-select signal that the difference by the 1st shared non-select signal and the 1st data-signal constitutes, thereafter, next common electrode is elected to be shared selection electrode, carry out rewriting work, by repeating this rewriting work, rewrite the show state of the liquid crystal that constitutes whole pixels.
During whole non-selections of pixel, whole common electrodes is applied the 2nd shared non-select signal, whole segmented electrodes is applied the 2nd data-signal, the liquid crystal that constitutes whole pixels is applied the 2nd non-select signal that the difference by these signals constitutes, whole pixels are maintained nonselection mode.
In above driving method, be set at following drive condition in the voltage waveform shown in Figure 10.
Plane resets condition: 35V, 20m second (50Hz), 1 cycle was rewritten condition:
The frequency of the voltage waveform that applies is 500Hz, 640 cycles
The setting of voltage, the focal circle awl is used: 12V (being equivalent to V2)
The plane is used: 23V (being equivalent to V0)
Non-selection waveform, 5.5V (being equivalent to (V0-V2)/2)
The whole non-alternative condition of pixel: 5.5V, 100Hz, 0～30 cycle (0～300m second) is variable
The voltage of the 2nd non-select signal during the voltage of the 1st non-select signal during the rewriting and the whole non-selections of pixel is identical, is 5.5V.
Near the relation of the optical characteristics of the pixel time that during rewriting shown in Figure 11, Figure 12, finishes the 2nd non-select signal after-applied and the 640th common electrode of liquid crystal display cells.Figure 11 illustrates the visual sense reflectivity, and Figure 12 illustrates contrast.
If extend during rewriting the non-selection of whole pixels after finishing, then
The reflectivity on plane is 19%, changes hardly.
The reflectivity of focal circle awl descends.Saturation value is 6.3%.
As a result of, contrast has improved.
If plan to carry out the demonstration of 16 gray scales, if supposition carried out a gray scale must discrete being suppressed at (plane reflection rate-focal circle awl reflectivity)/(16-1) when showing with the reflectivity of viewing area integral body in, then under the situation of this panel, be 6.3+ (19-6.3)/15=7.1 (%), the reflectivity of focal circle awl must be suppressed at smaller or equal to 7.1%.
The result who applies common electrode (COM No.) and the relation of focal circle awl reflectivity behind the voltage waveform shown in Figure 10 that studied shown in Figure 13.Time among the figure (m second) shows at the application time that last common electrode (COM640) has been applied the whole pixel non-select signals that then applied after selecting signal (0m second be comparative example).
According to Figure 13 as can be known, by selecting the after-applied about 10m of the signal whole pixel non-select signals of second having applied, the reflectivity that can make the plane is smaller or equal to 7.1%.That is, on whole of viewing area, can obtain uniform gray scale demonstration by applying 10m whole pixel non-select signals of second, we can say.
In the present embodiment, under the situation of having considered the liquid crystal indicator of the reality of use STN driver IC in common driver and segment drivers, the voltage change-over switch 20 shown in Figure 14 preferably is set changes at reseting period and the maximum voltage of the pulse voltage that applies during rewriting.In Figure 14, the voltage of plane resets one side is set at 35V, the voltage of rewriting a side is set at 23V.When V0=23V, resistance R 1, R2, R3, R4, R5 be set at make V1=17.5V, V2=12V, V3=11V, V4=5.5V, V5=0V.The common driver of STN driver IC and the voltage that segment drivers can both be exported 4 level that comprise 0V have been used.In plane resets, a shared side might as well, segmentation one side might as well, output is V0 and these 2 level of V5 just.Have again, utilize the controller 16 shown in Fig. 7 to control voltage change-over switch 20.
In the present embodiment, the voltage of the 2nd non-select signal during the voltage of the 1st non-select signal during the rewriting and the whole non-selections of pixel is identical, is 5.5V, but is provided with during the non-selection of whole pixels, and other display characteristic is worsened.If same effect is arranged, then sequential of the voltage of the 2nd non-select signal, frequency or its input etc. is all unrestricted.
For example, for voltage, the maximum voltage of the 2nd non-select signal is greater than 0V, smaller or equal to 2 times of the maximum voltage of the non-select signal during rewriting.This be because, if this voltage is smaller or equal to 0V, then will not rewrite the effect that the reflectivity of pixel of the focal circle taper attitude of the last common electrode periphery that finishes is kept lessly, in addition, if 2 times of the maximum voltage of the non-select signal during surpass rewriting then are applied in the reflectivity of selecting signal and becoming the pixel of flat state and descend.The voltage of the 2nd non-select signal during making the non-selection of whole pixels by this way become with rewrite during the situation of the different value of the voltage of the 1st non-select signal under, be preferably in the voltage change-over switch 22 shown in Figure 15 be set in the STN driver IC.Certainly, by the voltage change-over switch 22 shown in Figure 15 is set, also it doesn't matter even export the 2nd non-select signal in the voltage of plane resets is set.Have again, utilize the controller 16 shown in Fig. 7 to control voltage change-over switch 22.
In addition, during rewriting and between during whole non-selection of pixel, the 0V interval can be set, after finishing during whole non-selections of pixel, even also it doesn't matter during the non-selection of the 2nd, the 3rd whole pixels was set.
In addition, in the present embodiment, implemented plane resets with the voltage waveform of 35V, 50Hz, if but whole of viewing area can be reset to flat state, and then the waveform of voltage or frequency etc. is unrestricted.The 0V interval can be set in reseting period.
As cholesteric crystal display element 10, but use has mixed the system chiral reagent CB-15 of Mei Er society of 0.2g in the big Japanese ink chemical industry system nematic liquid crystal RPD-84202 of society of 0.7g and the Xu Dianhuagongyeshe of 0.1g makes the cholesteric crystal that chiral reagent CNL-617R obtains, and makes the cholesteric crystal display element shown in Fig. 8.The thickness of liquid crystal layer is 4.5 μ m.Alignment films 4 among Fig. 8 is vertical alignment layers.In addition, on the face opposite, carried out the printing of black with sightingpiston.
To the common electrode number is that 640, segmented electrode number are that the liquid crystal display cells of any bar has applied the pulse voltage with the voltage waveform shown in Figure 16, has measured the visual sense reflectivity of viewing area.Drive condition is as described below.
Plane resets condition: 33V, 10m second (100Hz), 2 cycles were rewritten condition:
The frequency of the voltage waveform that applies is 500Hz (being equivalent to shared selection signal is the 2m length of second)
Non-selection waveform is 5.0V (being equivalent to (V0-V2)/2)
The whole non-alternative condition of pixel: 5.5V, 100Hz, 10 cycles (10m second)
Have again, in Figure 16,, also show the voltage waveform that does not have during the non-selection of whole pixels in order to compare.
Near the visual sense reflectivity of the pixel during the selection of shown in Figure 17 and Figure 16 the 640th common electrode of suitable pulse voltage and liquid crystal display cells.By during the non-selection of whole pixels is set, do not change in the visual sense reflectivity of the pixel of flat state, but the visual sense reflectivity of the pixel of focal circle taper attitude (in the part of family curve two-story valley) is kept under low state as can be known.That is,, can obtain the good demonstration of contrast by during the non-selection of whole pixels is set.
The liquid crystal display cells identical with embodiment 3 applied the pulse voltage shown in Figure 18, measured the visual sense reflectivity of viewing area.Result shown in Figure 19.After during rewriting, finishing as can be known, during the additional non-selection of whole pixels,, almost as broad as long in the visual sense reflectivity at the common electrode COM640 periphery that the common electrode COM1 periphery and the rewriting that begin to rewrite finish.Promptly, in the display pixel area when display pixel area that begins rewriting operation and rewriting operation end, for the two condition of flat state and focal circle taper attitude, reflectivity much at one, thereby utilize rewrite at a high speed obtained display characteristic be constant, do not show irregular demonstration.
In the present embodiment, considering to use STN to drive under the situation with the liquid crystal indicator of the reality of driver IC, be preferably in plane resets during, rewrite during and all during the non-selection of pixel between the voltage change-over switch 22 shown in Figure 15 is set.In Figure 15, with the voltage during the plane resets be decided to be 33V, to be decided to be 20～24V be suitable for voltage during will rewriting.All the voltage during the non-selections of pixel is decided to be 1.1 times of voltage during the rewriting.In Figure 15, the voltage during the above-mentioned rewriting is V0, makes V1=V0-5 (V), V2=V0-10 (V), V3=10V, V4=5V, V5=0V by resistance R 1, R2, R3, R4, R5 are set at, and the voltage waveform shown in available Figure 18 drives.
The liquid crystal display cells of having made in embodiment 3 is applied the voltage waveform shown in Figure 20, Figure 21, carried out gray scale and show, measured the visual sense reflectivity.Figure 21 is the figure that has amplified the selection signal of Figure 20, and the waveform of respectively selecting signal of realizing gray scale 1～gray scale 16 is shown.In the waveform of Figure 21,, planar orientation (p=1, q=0), focal circle awl orientation (p=0, q=1) and intermediateness arbitrarily thereof have been formed by the ratio of p, q during changing.
In the present embodiment, considered the meticulous demonstration of 16 gray scales, for the reflectivity of flat state, the reflectivity of focal circle taper attitude have been carried out the selection signal of 14 totals of cutting apart, 16 kinds, near the pixel the common electrode COM1 that begins rewriting operation respectively with become near the pixel that rewriting operation finishes the contiguous common electrode COM640 and measured the visual sense reflectivity.In table 1, measurement result is shown for the situation that is provided with and is not provided with during the non-selection of whole pixel of the present invention.
Table 1
As shown in table 1, if be not provided with during the non-selection of whole pixels, then particularly approach a side (in transmission mode) of focal circle taper attitude in gray shade scale, between common electrode COM1 and common electrode COM640, in the visual sense reflectivity, produce significant difference, gray scale shows disorderly significantly, and in the embodiments of the invention during being provided with the non-selection of whole pixels, in whole common electrode of the 1st～the 640th, the disorder that gray scale shows does not almost have the difference of visual sense demonstration smaller or equal to 0.5%.
Be 18.8% at the saturation value of the visual sense reflectivity of the pixel of flat state, the saturation value of the visual sense reflectivity of the pixel of focal circle taper attitude is under 3.6% the situation, if planning to carry out 16 gray scales shows, then carrying out gray scale when showing, must discrete being suppressed at (plane reflection rate-focal circle awl reflectivity)/(16-1)=(18.8-3.6)/15 ≈ 1 (%) with the visual sense reflectivity of viewing area integral body in.As shown in table 1, by during the non-selection of whole pixels is set, in each gray scale, the visual sense reflectivity among the common electrode COM1 and the difference of the visual sense reflectivity among the common electrode COM640 are suppressed in 1%, as can be known generally, can realize that uniform gray scale shows for display pixel.That is, utilize embodiment can be shown not that irregular high gray scale shows as can be known.
Claims (15)
1. the driving method of a liquid crystal display cells, in above-mentioned liquid crystal display cells, by the common electrode group that on the surface of glass substrate, is provided with, on the surface of the opposing party's who disposes opposed to each other with above-mentioned glass substrate glass substrate and and the direction of the direction quadrature of above-mentioned common electrode group on the sets of segment electrodes that is provided with and be clipped in and demonstrate cholesterol liquid crystal mutually with rectangular formation pixel between above-mentioned common electrode group and the sets of segment electrodes, when above-mentioned pixel not being applied voltage, utilize the Memorability of liquid crystal to keep by flat state, the show state that focal circle taper attitude or their intermediateness constitute, for above-mentioned liquid crystal display cells, utilization applies voltage to the difference of the voltage that above-mentioned common electrode and segmented electrode apply to above-mentioned pixel, it is characterized in that, comprise following step:
Whole pixels are reset to the step of flat state;
Rewrite the step of the show state of whole pixels; And
Whole pixels are maintained the step of nonselection mode,
Wherein, whole pixels being reset in the above-mentioned steps of flat state, whole common electrodes is applied shared reset signal, whole segmented electrodes is applied data reset signal, whole pixels is applied the reset signal that the difference by these signals constitutes, make whole pixels become flat state;
In the above-mentioned steps of the show state of rewriting whole pixels, carry out following rewriting work, promptly, certain common electrode is elected to be shared selection electrode, other common electrode is elected to be shared non-selection electrode, shared selection electrode is applied shared selection signal, simultaneously shared non-selection electrode is applied the 1st shared non-select signal, with shared selection signal Synchronization ground segmented electrode is applied the 1st data-signal, pixel on the shared selection electrode is applied the selection signal that the difference by shared selection signal and the 1st data-signal constitutes select show state, in addition, pixel on the shared non-selection electrode is applied the 1st non-select signal that the difference by the 1st shared non-select signal and the 1st data-signal constitutes, thereafter, next common electrode is elected to be shared selection electrode, carry out above-mentioned rewriting work,, rewrite the show state of the liquid crystal that constitutes whole pixels by repeating this rewriting work;
Whole pixels are being maintained in the above-mentioned steps of nonselection mode, whole common electrodes is applied the 2nd shared non-select signal, whole segmented electrodes is applied the 2nd data-signal, whole pixels is applied the 2nd non-select signal that the difference by these signals constitutes, so that whole pixels are maintained nonselection mode.
2. the driving method of liquid crystal display cells as claimed in claim 1 is characterized in that:
With whole pixels be maintained above-mentioned nonselection mode during be 5～200m second.
3. the driving method of liquid crystal display cells as claimed in claim 2 is characterized in that:
Above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the maximum voltage of above-mentioned the 2nd non-select signal is greater than 0V, smaller or equal to 2 times of the maximum voltage of above-mentioned the 1st non-select signal.
4. the driving method of liquid crystal display cells as claimed in claim 2 is characterized in that:
Above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the minimum voltage of above-mentioned the 2nd non-select signal is less than 0V, more than or equal to 2 times of the minimum voltage of above-mentioned the 1st non-select signal.
5. the driving method of liquid crystal display cells as claimed in claim 2 is characterized in that:
Above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the maximum voltage of these each non-select signals is identical, minimum voltage is also identical.
6. the driving method of liquid crystal display cells as claimed in claim 2 is characterized in that:
Above-mentioned the 1st non-select signal and above-mentioned the 2nd non-select signal all are pulse voltages, and the frequency of above-mentioned the 2nd non-select signal is more than or equal to the frequency of above-mentioned the 1st non-select signal, smaller or equal to 5Hz.
7. the driving method of liquid crystal display cells as claimed in claim 2 is characterized in that:
In the above-mentioned steps of the show state of rewriting whole pixels, above-mentioned selection signal is a pulse voltage, and 1 cycle of this pulse voltage is 0.5～5m second.
8. the driving method of liquid crystal display cells as claimed in claim 2 is characterized in that:
Whole pixels are being maintained in the above-mentioned steps of flat state, above-mentioned reset signal are being decided to be pulse voltage more than or equal to 30V,
In the above-mentioned steps of the show state of rewriting whole pixels, the above-mentioned selection signal that will be used to make pixel become focal circle taper attitude is decided to be the pulse voltage of 7～15V, and the above-mentioned selection signal that perhaps will be used to make pixel become flat state is decided to be the pulse voltage of 16～28V.
9. cholesteric crystal display device possesses:
Liquid crystal display cells, by on the common electrode group that is provided with on the surface of glass substrate, the surface at the opposing party's who disposes opposed to each other with above-mentioned glass substrate glass substrate and and the direction of the direction quadrature of above-mentioned common electrode group on the sets of segment electrodes that is provided with and the cholesterol liquid crystal mutually that demonstrates that is clipped between above-mentioned common electrode group and the sets of segment electrodes constitute pixel with rectangular, when above-mentioned pixel not being applied voltage, utilize the Memorability of liquid crystal to keep the show state that constitutes by flat state, focal circle taper attitude or its middle state;
Common driver is exported shared reset signal, shared selection signal and shared non-select signal to above-mentioned common electrode group;
Segment drivers is to above-mentioned sets of segment electrodes output data reset signal and data-signal;
And controller, control above-mentioned common driver and segment drivers,
It is characterized in that:
Above-mentioned controller so that above-mentioned common driver and segment drivers utilization each described driving method in claim 1～8 mode that the pixel of above-mentioned liquid crystal display cells applies voltage is controlled.
10. cholesteric crystal display device as claimed in claim 9 is characterized in that:
Above-mentioned common driver output comprises the voltage of 4 level of 0V,
Above-mentioned segment drivers output comprises the voltage of 4 level of 0V,
Identical from the maximum voltage of above-mentioned common driver output with the maximum voltage of exporting from above-mentioned segment drivers, also possess the voltage change-over switch that above-mentioned each maximum voltage is converted at least 2 magnitudes of voltage.
11. cholesteric crystal display device as claimed in claim 10 is characterized in that:
Above-mentioned controller is controlled above-mentioned voltage change-over switch, to change the maximum voltage of the pulse voltage that is applied in the above-mentioned steps of above-mentioned steps that whole pixels is reset to flat state and the element state of rewriting whole pixels.
12. cholesteric crystal display device as claimed in claim 10 is characterized in that:
Above-mentioned controller is controlled above-mentioned voltage change-over switch, with in the above-mentioned steps of the element state of rewriting whole pixels with whole pixels are maintained the maximum voltage of conversion pulse voltage in the above-mentioned steps of nonselection mode.
13. cholesteric crystal display device as claimed in claim 9 is characterized in that:
On above-mentioned common electrode group and above-mentioned sets of segment electrodes, cover the vertical alignment layer that is formed with polyimide.
14. cholesteric crystal display device as claimed in claim 9 is characterized in that:
Distance between above-mentioned common electrode group and the sets of segment electrodes is 3.5 μ m～6 μ m.
15. cholesteric crystal display device as claimed in claim 9 is characterized in that:
The number that constitutes the common electrode of above-mentioned pixel is more than or equal to 320.
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| JP2004068720A JP4313702B2 (en) | 2004-03-11 | 2004-03-11 | Liquid crystal display element and driving method thereof |
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| JP4644156B2 (en) * | 2006-05-15 | 2011-03-02 | 富士通フロンテック株式会社 | Memory liquid crystal reset method and liquid crystal display device |
| JP2008170536A (en) * | 2007-01-09 | 2008-07-24 | Seiko Epson Corp | Display driving device, display device and electronic equipment |
| JP5272487B2 (en) * | 2008-04-09 | 2013-08-28 | 富士通株式会社 | Dot matrix type display device |
| JP2010044258A (en) * | 2008-08-14 | 2010-02-25 | Fujitsu Ltd | Cholesteric liquid crystal display element and method for driving the same |
| CN102203848B (en) | 2008-10-30 | 2013-08-21 | 夏普株式会社 | Liquid crystal display driving circuit and liquid crystal display device |
| JPWO2010106576A1 (en) * | 2009-03-18 | 2012-09-13 | 富士通フロンテック株式会社 | Nonvolatile liquid crystal display device and display method of nonvolatile liquid crystal display device |
| JP5310517B2 (en) * | 2009-12-08 | 2013-10-09 | 富士通株式会社 | Liquid crystal drive method |
| US8217930B2 (en) * | 2009-08-27 | 2012-07-10 | 3M Innovative Properties Company | Fast transitions of large area cholesteric displays |
| CN102013243A (en) * | 2010-12-28 | 2011-04-13 | 华映视讯（吴江）有限公司 | Method for driving cholesterol liquid crystal display device |
| CN104749804A (en) * | 2013-12-26 | 2015-07-01 | 凌巨科技股份有限公司 | LCD (Liquid Crystal Display) equipment for cholesterol as well as drive circuit and drive method thereof |
| CN106782257B (en) * | 2015-11-20 | 2020-03-17 | 晶门科技有限公司 | Apparatus and method for driving electronic paper display |
| KR20170110771A (en) * | 2016-03-23 | 2017-10-12 | 삼성디스플레이 주식회사 | Head-mounted device and display device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1322338A (en) * | 1999-07-21 | 2001-11-14 | 皇家菲利浦电子有限公司 | Unipolar driving of bistable cholesteric liquid crystal display |
| US20010048414A1 (en) * | 2000-05-29 | 2001-12-06 | Minolta Co., Ltd. | Liquid crystal display device and method for driving a liquid crystal display |
| JP2002062520A (en) * | 2000-08-18 | 2002-02-28 | Fuji Xerox Co Ltd | Cholesteric liquid crystal display device |
| US20030122758A1 (en) * | 2001-12-27 | 2003-07-03 | Nam-Seok Lee | Method of driving cholesteric liquid crystal display panel for accurate gray-scale display |
| US20030206147A1 (en) * | 2002-05-03 | 2003-11-06 | Eastman Kodak Company | General 2 voltage levels driving scheme for cholesterical liquid crystal displays |
| CN1461962A (en) * | 2002-05-30 | 2003-12-17 | 那纳须株式会社 | Liquid crystal display |
-
2004
- 2004-03-11 JP JP2004068720A patent/JP4313702B2/en not_active Expired - Fee Related
-
2005
- 2005-03-08 TW TW094106911A patent/TW200601225A/en unknown
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1322338A (en) * | 1999-07-21 | 2001-11-14 | 皇家菲利浦电子有限公司 | Unipolar driving of bistable cholesteric liquid crystal display |
| US20010048414A1 (en) * | 2000-05-29 | 2001-12-06 | Minolta Co., Ltd. | Liquid crystal display device and method for driving a liquid crystal display |
| JP2002062520A (en) * | 2000-08-18 | 2002-02-28 | Fuji Xerox Co Ltd | Cholesteric liquid crystal display device |
| US20030122758A1 (en) * | 2001-12-27 | 2003-07-03 | Nam-Seok Lee | Method of driving cholesteric liquid crystal display panel for accurate gray-scale display |
| US20030206147A1 (en) * | 2002-05-03 | 2003-11-06 | Eastman Kodak Company | General 2 voltage levels driving scheme for cholesterical liquid crystal displays |
| CN1461962A (en) * | 2002-05-30 | 2003-12-17 | 那纳须株式会社 | Liquid crystal display |
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| CN1667462A (en) | 2005-09-14 |
| TW200601225A (en) | 2006-01-01 |
| JP2005257999A (en) | 2005-09-22 |
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