JP2976983B2 - Driving method of liquid crystal panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] Regarding a driving method of a liquid crystal panel, when a liquid crystal panel having a simple matrix structure is driven by using a voltage averaging method, generation of luminance unevenness depending on a display pattern for each line is described. A matrix type liquid crystal panel provided with data electrodes and scan electrodes intersecting with each other is controlled by a voltage averaging method having a positive voltage application mode period and a negative voltage application mode period for the purpose of suppressing the change regardless of a change in drive voltage. The scan electrode or the data electrode is driven for each scan electrode drive time by applying a correction voltage corresponding to the data displayed on the selected scan electrode with the opposite polarity between the positive voltage application mode period and the negative voltage application mode period. In a method of driving a liquid crystal panel for removing crosstalk by adding a selection voltage or a non-selection voltage of the same polarity or the opposite polarity to the same, The positive voltage is changed according to the magnitude of the driving voltage of the liquid crystal panel.

[Industrial applications]

The present invention relates to a method and a device for driving a liquid crystal panel having a simple matrix structure.

In recent years, with the spread of personal computers, word processors, and the like, the adoption of a liquid crystal display device that is lightweight, thin, and can be driven by a battery has become remarkable as a display device instead of a large-sized and power-consuming CRT. Driving methods for liquid crystal display devices are roughly classified into simple matrix type and active matrix type.The active matrix type is difficult to manufacture because each pixel requires a non-linear element. Display devices generally employ a simple matrix structure.

However, in a display device having a simple matrix structure, as the display capacity is increased, display unevenness (crosstalk) depending on the display pattern occurs due to its characteristics, and display quality deteriorates. Therefore, it is strongly desired to eliminate the display unevenness. ing.

[Conventional technology]

FIG. 11, in the liquid crystal panel of simple matrix structure shown in FIG. 12, "bright" when the write (of the liquid crystal display is a liquid crystal display device of the entire line as the X ₁ row and X ₂ columns ○ ), And the driving waveform of the liquid crystal panel when writing “dark” (the display of the liquid crystal is ●). In FIG. (A) is X ₁ column of data voltage application waveform (thick line),
X is a data voltage application waveform (dotted line) of _two columns, and (b) is Y ₁
Scan voltage waveform applied row, and (c) Y ₂ rows of scan voltage waveform applied, it is (d) the drive voltage waveform of the cell alpha (thick line), the driving voltage waveform of the cell beta (dotted line).

The conventional driving method employs the voltage averaging method shown in FIG. 13, in which the first cycle is selected during one frame period and the second cycle is selected in the next frame. Switching between the first period and the second period every several lines is practically used, and a DC component is not applied to the liquid crystal to realize highly reliable driving without deteriorating the panel characteristics.

The switching between the first cycle and the second cycle is called polarity inversion, and the control signal thereof is called a polarity inversion signal.

By the way, in a conventional liquid crystal display device having a simple matrix structure, it is known that as the display capacity is increased, display unevenness (crosstalk) depending on the characteristic display pattern occurs, and the display quality is deteriorated. The crosstalk includes a first crosstalk as shown in FIG. 5 and a second crosstalk as shown in FIG.

The first crosstalk shown in FIG. 5 (a) is composed of a "bright" display cell A on a scan electrode, which is often "dark", and a "bright" display cell.
In the "bright" display cell B on the scan electrode, which has many displays,
Even in the same "bright" display, there is a difference in luminance. Also, the second crosstalk shown in FIG.
When the horizontal stripes of “bright” and “dark” on the same scan electrode are repeatedly displayed while changing the phase and width, the cell C on the data electrode with a narrow “dark” display and the “dark” display There is a difference in luminance between the cell D and the cell D on the data electrode having a wide width.

Therefore, as a method of eliminating the first crosstalk, a method of driving a liquid crystal panel in which the number of "1" s when a certain line is selected is counted, and a correction voltage according to the value is superimposed on a selection voltage of the scan electrode driver. Or, the driving method of adding the selection voltage of the data electrode, the non-selection voltage of the data electrode, and the non-selection voltage of the scan electrode, or the addition to the selection voltage of the scan electrode, and the addition to the selection voltage of the scan electrode The applicant has proposed a driving method in which the selection voltage of the data electrode, the non-selection voltage of the data electrode, and the non-selection voltage of the scan electrode are added with opposite polarities. Also, as a method of eliminating the second crosstalk,
When a scan electrode is selected and the next scan electrode is selected, the difference between the number of display data changes from “1” to “0” and the number of display data changes from “0” to “1” is calculated, and the difference is calculated. The applicant has proposed a method of driving a liquid crystal panel in which a correction voltage is superimposed on a non-selection voltage of a scan electrode driver, or a method of driving a liquid crystal panel in which a correction voltage is superimposed on a selection voltage and a non-selection voltage of a data electrode.

By the way, in an actual liquid crystal display device, in order to set a drive voltage, a luminance adjustment circuit is provided so that display luminance can be adjusted according to the surrounding brightness. This brightness adjustment circuit includes a variable resistor (brightness adjustment volume) provided between the DC power supply _VEE and the ground, and the drive voltage of the liquid crystal cell is set by the variable output voltage _VLCD . For example, if the brightness adjustment volume is adjusted in a direction to increase the output voltage of the brightness adjustment circuit (hereinafter referred to as brightness adjustment voltage) _VLCD , the voltage applied to the liquid crystal cell increases, and the display brightness of the cell increases. When the brightness adjustment volume is adjusted in a direction to decrease the brightness adjustment voltage _VLCD , the voltage applied to the liquid crystal cell is reduced, and the display brightness of the cell is reduced.

[Problems to be solved by the invention]

However, when the display luminance of the liquid crystal panel is changed, there is a problem that crosstalk cannot be completely prevented by the above-mentioned correction voltage (this is ΔVm). For example, when the first crosstalk is prevented by the above-described correction voltage, the transmittance-driving voltage characteristic (TV characteristic) when the light transmittance of the cells A and B is measured by changing the brightness adjustment voltage is the second. Fig. 5 (b)
Shown in As shown in this figure, in the liquid crystal cell A (indicated by a dotted curve) in an area where no crosstalk occurs,
Liquid crystal cell B in a region where crosstalk occurs and becomes dark
The tilt angle of the TV characteristic is larger than that of the curve (shown by a solid curve), so that the occurrence of crosstalk can be prevented only when the brightness adjustment voltage V _LCD is set to V _LCD1 .

Similarly, in the second crosstalk, the TV characteristics of the liquid crystal cell D, which becomes dark due to the occurrence of the crosstalk, are more inclined than the liquid crystal cell C, which does not generate the crosstalk. As shown in b), the _TV characteristics do not match at points other than the point at which the luminance adjustment voltage V _LCD is V _LCD4 , and the luminance adjustment voltage V _LCD does not match.
_{When the LCD} was changed, there was a problem that crosstalk occurred.

The present invention solves the problem of the conventional simple matrix type liquid crystal display device, and even if the luminance adjustment voltage is changed,
It is an object of the present invention to provide a liquid crystal panel driving method capable of suppressing occurrence of luminance unevenness.

[Means for solving the problem]

A method for driving a liquid crystal panel according to the present invention that solves the conventional problems includes a matrix type liquid crystal panel provided with data electrodes and scan electrodes crossing each other, having a positive voltage application mode period and a negative voltage application mode period. In the driving method using the voltage averaging method, in the first embodiment, as shown in FIG.
A correction voltage is determined for each scan electrode driving time in accordance with the data displayed on the selected scan electrode, and then the correction voltage is corrected according to the magnitude of the driving voltage of the liquid crystal panel, and the corrected correction is performed. The voltage has the opposite polarity between the positive voltage application mode period and the negative voltage application mode period, and is added to the selection voltage or the non-selection voltage of the scan electrode or the data electrode with the same polarity or the opposite polarity.

[Action]

According to the present invention, when the correction voltage at the time of selection or non-selection of the scan electrode is determined according to the display pattern for each line, the correction voltage is appropriately corrected according to the luminance adjustment voltage. As a result, the TV characteristics of the brightened cells and the darkened cells due to the occurrence of crosstalk match,
Even if the luminance adjustment voltage is changed, a high quality display can be obtained.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, an example in which the method of the present invention is applied to the second crosstalk shown in FIG. 6 will be described.

FIG. 2 is a circuit diagram showing a configuration of an embodiment of a liquid crystal panel driving device embodying the present invention. In the figure, a data electrode driver (X driver) 21 is applied to a data electrode of a liquid crystal panel 23, and a scan electrode driver (Y driver) is applied to a scan electrode.
Drivers) 22 are connected respectively. Reference numeral 24 denotes a power supply circuit which divides between two potentials V _LCD and GND with a plurality of resistors to generate voltages V _{1 to} V ₆ . The voltage V ₁ ~V ₆ 10
A voltage required for the implementation of voltage averaging side described in Fig., The _{value, V 1 = V V 4 =} (2 / a) V V 2 = (1-1 / a) V V 5 = (1 / a) V V ₃ = (1-2 / a) V V ₆ = 0, where a is a number determined by the duty ratio.

The potential V _LCD is connected to the brightness adjustment volume 30 connected to the supply voltage V _EE. Therefore, the potential _VLCD is changed by adjusting the brightness adjustment volume 30.

The data electrode driver 21 is supplied with the voltages V ₁ , V ₃ , V ₄ , and V ₆ from the power supply circuit 24, and the scan electrode driver 22 receives the voltages from the power supply circuit 24 through a correction voltage addition circuit 29 described later. Each potential of V ₁ , V ₂ , V ₅ and V ₆ is applied. A liquid crystal panel controller 26 is connected to the data electrode driver 21 and the scan electrode driver 22. The liquid crystal panel control device 26 sends X data XDATA and Y data YDATA, which are liquid crystal panel display data, to the data electrode driver 21 and the scan electrode driver 22 in response to a command from a control device such as a personal computer 25. , And a signal DF for switching between the positive voltage application mode period and the negative voltage application mode period (hereinafter, an example in which switching is performed for each frame will be described). It is.

The data electrode driver 21 and the scan electrode driver 22 receive X data XDATA from the liquid crystal panel controller 26,
Each data electrode of the liquid crystal panel 23 according to the Y data YDATA,
And the aforementioned voltage V ₁ from the power supply circuit 24 to each scan electrode.
Providing by selecting one of ~V _6. That is, during the positive voltage application mode, the data electrode driver 21 outputs the X data XD
0 is applied to the data electrode selected based on the ATA, and (2 / a) V is applied to the non-selected data electrode. The scan electrode driver 22 applies the selected scan electrode to the selected scan electrode based on the Y data YDATA. V for non-selected scan electrodes (1 / a)
V is applied. Similarly, during the negative voltage application mode period, the data electrode driver 21 applies V to the data electrode selected based on the X data XDATA and (1) to the unselected data electrode.
−2 / a) V is applied, and the scan electrode driver 22 applies 0 to the selected scan electrode based on the Y data YDATA.
And (1-1 / a) V is applied to unselected scan electrodes.

In this embodiment, in addition to the above configuration, a correction parameter generation circuit 27, a D / A conversion circuit 28, a correction voltage addition circuit 29, and a luminance adjustment voltage conversion circuit 31 are provided. The correction parameter generation circuit 27 includes a data latch circuit 271 that fetches X data XDATA in synchronization with the data clock signal DCLK, and a data detection circuit 272 that detects “ON” data from the output of the data latch circuit 271 and the data clock signal DCLK. "ON" after receiving the output of the data detection circuit 272
It comprises a counter 273 for determining the number of data and a latch 274. A scan synchronization signal SSYNC for synchronizing scan electrode driving is connected to the initialization input RST of the counter 273 and the clock input CK of the latch 274, and the count result is latched every one scan driving period. 273 is reset and set to the initial state.

The D / A conversion circuit 28 generates a correction voltage, and converts the digital count result output from the latch 2747 to a corresponding voltage value. Further, the correction voltage addition circuit 29 and the adder circuit 291 for adding the correction voltage to the scan electrode selection voltage V ₁ of the power supply circuit 24, an inverting circuit 292 for inverting the correction voltage, to the scan electrode selection voltage V ₆ of the power supply circuit 24 An addition circuit 293 for adding the inverted correction voltage is provided. The brightness adjustment voltage conversion circuit 31 includes a power supply 311 for generating the reference voltage Vf and a voltage adjustment volume 312.

Next, the operation of the circuit configured as described above will be described. X data output from liquid crystal panel controller 26
XDATA is sent to the data electrode driver 21 and simultaneously taken into the data latch circuit 271 therein by the correction parameter generation circuit 27 in synchronization with the data clock signal DCLK, and is output immediately after latching. Then, a pulse is output from the data detection circuit 272 only when the X data XDATA is "ON" by taking the logical product of the output of the data clutch circuit 271 and the data clock signal DCLK in the data detection circuit 272. A scan synchronization signal SSYNC for synchronizing scan electrode driving is input to an initialization input RST of the counter 273 to which this output is input, and the counter 273 is reset every one scan driving period. In the above, the number of “ON” in the X data XDATA in one scan driving period is counted by the number of rising or falling edges of the pulse output from the data detection circuit 272, and the result is output from the latch 274 as a correction parameter. .

This correction parameter output is converted into a voltage by a D / A conversion circuit 28, which is a subsequent correction voltage generation circuit, and output as a correction voltage. This correction voltage is applied to a correction voltage addition circuit.
Is directly input to the adder 291 in the 29, the scan electrode selection voltages V ₁ is corrected. Also, this correction voltage is
292 is inverted is input to the addition circuit 293 through the scan electrode selection voltage V ₆ in the opposite direction is corrected to the correction of the scan electrode selection voltage V _1. This correction voltage is the X data XDATA
The value becomes larger as the number of “on” in the inside increases.

Then, when the brightness adjustment volume 30 is adjusted and the potential V _LCD of the power supply circuit 24 is changed, the potential V _LCD is input to the brightness adjustment voltage conversion circuit 31, and the brightness adjustment voltage V _LCD is set to the resistance of the adjustment volume 312. D / A conversion circuit with reference voltage Vf
28 power supply voltages are changed. Therefore, by changing the power supply voltage, the correction voltage is also changed according to the adjustment of the brightness adjustment volume 30.

As a result, as shown in FIG.
_{When the LCD} has a low value (V _LCD2 ), the correction voltage ΔV has a low value (Δ
V ₂ ), and when the luminance adjustment voltage V _LCD is a high value (V _LCD3 ), the correction voltage ΔV has a high value (ΔV ₃ ). The correction voltage ΔV at this time is represented by the following equation: ΔV = ΔVm × k (V _LCD −Vf). Here, ΔVm is a conventional correction voltage amount, and k and Vf are coefficients. Therefore, appropriate correction according to the brightness adjustment voltage _VLCD is performed, and the TV characteristics of the cell in which the crosstalk has occurred and the cell in which the crosstalk has not occurred match, and even if the brightness adjustment voltage _VLCD is changed. Good display quality can be obtained.

Next, an example in which the method of the present invention is applied to the second crosstalk shown in FIG. 6 will be described. FIG. 3 shows the configuration of a driving device for a liquid crystal panel embodying the present invention. The configuration of this driving device is almost the same as the configuration of the driving device shown in FIG. Are denoted by the same reference numerals, and only the configuration different from the apparatus in FIG. 2 will be described.

The apparatus of FIG. 3 differs from the apparatus of FIG. 2 in the configuration of the correction parameter generation circuit 27, and a down counter 275 is further added to the apparatus of FIG. Down counter 275
And the output of the data detection circuit 272 is input to the clock input CK of the counter 273. The scan synchronization signal SSYNC is input to the initialization input RST of the down counter 275 and the data load input LOAD of the counter 273, and the value of the counter 273 is latched by the latch 274 every one scan driving period, and the calculation result of the down counter 275 is obtained. Is loaded into the counter 273, the down counter 274 is reset, and the output of the latch 274 is D / A
Convert. In addition, a different configuration of the correction voltage addition circuit 32, in the apparatus of FIG. 2 and voltages V ₁ in the power supply circuit 24
V ₆ , that is, the correction voltage was superimposed on the selection voltage of the scan electrode, but in this device, the voltage V ₂ in the power supply circuit 24 is
V _5, that is, the correction voltage to the non-selected voltage of the scanning electrode is adapted to be superimposed. Therefore, the correction voltage adding circuit
The 32, an adding circuit 321 to match the voltage V ₂ plus the output of the D / A conversion circuit 28, the inverter circuit 322 of the output of the D / A conversion circuit 28,
And, and a summing circuit 323 to match the voltage V ₅ adds the output of the D / A conversion circuit 28 is provided.

D / A conversion circuit 28 in the device configured as above
And the operation of the brightness adjustment voltage conversion circuit 31
The correction parameter generation circuit 27 counts the difference between the number of “ON” in the X data XDATA between a certain one scan drive period and the next one scan activation period.
The result is output as a correction parameter. And
The correction voltage is generated in the D / A conversion circuit 28 by the output of the correction parameter, and the correction voltage is
Adder circuit 321 is directly input to the scan electrode the non-selection voltage V ₂ in 32 is corrected, adding through inverting circuit 322 circuit 3
Are input is inverted scan electrode non-selection voltage V ₅ is corrected to 23.

Then, when the brightness adjustment volume 30 is adjusted and the potential V _LCD of the power supply circuit 24 is changed, this voltage V _LCD is input to the brightness adjustment voltage conversion circuit 31, and the brightness adjustment voltage V _LCD is set to the resistance of the adjustment volume 312. And the reference voltage Vf, the power supply voltage of the D / A conversion circuit 28 is changed. Therefore, by changing the power supply voltage, the correction voltage is also changed according to the adjustment of the brightness adjustment volume 30.

As a result, as shown in FIG.
When V _LCD has a low value (V _LCD5 ), the correction voltage ΔV has a low value (ΔV ₅ ), and the brightness adjustment voltage V _LCD has a high value (V _LCD6 ).
In this case, the correction voltage ΔV has a high value (ΔV ₆ ). The correction voltage ΔV at this time is represented by the following equation: ΔV = ΔVm × k (V _LCD −Vf). Here, ΔVm is a conventional correction voltage amount, and k and Vf are coefficients. Therefore, appropriate correction according to the brightness adjustment voltage _VLCD is performed, and the TV characteristics of the cell in which the crosstalk has occurred and the cell in which the crosstalk has not occurred match, and even if the brightness adjustment voltage _VLCD is changed. Good display quality can be obtained.

In the above two embodiments, the brightness adjustment voltage conversion circuit is used.
A power supply 311, which generates a reference voltage Vf, and an adjustment volume 3
12, the A / D conversion of the variation of the brightness adjustment voltage is performed, and the power supply voltage of the D / A conversion circuit 28 is determined in a digital value using a conversion table in accordance with the brightness adjustment voltage, and the D / A conversion is performed. The data may be converted and used as the power supply voltage of the D / A conversion circuit 28.

In the embodiment shown in FIG. 2, the correction voltage corresponding to the data displayed on the selected scan electrode is set to have the opposite polarity between the positive voltage application mode period and the negative voltage application mode period every one scan electrode driving time. In this case, the present invention is applied to a driving method for adding to the selection voltage of the scan electrode.
In the embodiment shown in the drawings, the present invention is applied to a driving method in which the correction voltage has the opposite polarity between the positive voltage application mode period and the negative voltage application mode period and is added to the non-selection voltage of the scan electrode. In the liquid crystal panel driving method according to the present invention, the correction voltage has a polarity opposite to that of the positive voltage application mode period and the negative voltage application mode period, the data electrode selection voltage, the data electrode non-selection voltage, and the scan electrode non-selection voltage. The driving method of adding the positive and negative voltages during the positive voltage application mode period and the negative voltage application mode period,
And a driving method of adding the selection voltage of the data electrode, the non-selection voltage of the data electrode and the non-selection voltage of the scan electrode with a polarity opposite to the case of adding to the selection voltage of the scan electrode, and a positive voltage application mode period. A driving method in which the polarity is opposite to that in the negative voltage application mode period and the data electrode selection voltage and the data electrode non-selection voltage are added is also applicable.

FIG. 7 shows the configuration of the correction voltage addition circuit 70 and the connection with the D / A conversion circuit 28 when the present invention is applied to the driving method shown in FIG. 7, where 71 to 76 are addition circuits, and 77 is an inversion circuit. is there. FIG. 8 shows the configuration of the correction voltage addition circuit 80 and the connection with the D / A conversion circuit 28 when the present invention is applied to the driving method shown in FIG. is there. FIG. 9 shows the configuration of the correction voltage adding circuit 90 and the connection with the D / A conversion circuit 28 when the present invention is applied to the driving method shown in FIG. Also in these configurations, D / A
The power supply of the conversion circuit 28 is a brightness adjustment voltage conversion circuit 31 not shown.
And the correction voltage changes, but the operation is exactly the same as in the above-described embodiment, and will not be further described.

In the above embodiment, the case where the panel temperature is constant is assumed. However, when the panel temperature changes from T ₁ ° C to T ₂ ° C (T ₁ > T ₂ ), the optimal correction voltage straight line is as shown in FIG. Translate to To cope with this, it is possible to change the reference voltage Vf according to the panel temperature. In order to change the reference voltage Vf, a structure in which the reference voltage Vf is changed by a volume or a structure in which the reference voltage Vf is automatically changed by using a thermistor or the like may be used.

Further, the bias ratio a is set to a theoretical optimum value. (However, D is a duty ratio). This method is disclosed in JP-A-59-160124, and has an effect of improving the contrast ratio in addition to the effect of reducing the driving voltage described in the publication. However, when this method is used alone, there is a problem in that the drive margin is narrowed, and the transmittance is largely changed by a slight change in the effective voltage, and crosstalk is likely to occur. Therefore, by suppressing the fluctuation of the effective voltage due to the display pattern in combination with the present invention, the problem of crosstalk can be solved, the driving voltage can be reduced, and the contrast ratio can be improved.

Incidentally, in the illustrated _{embodiment, V 1 = V V 4 =} (2 / a) V V 2 = (1-1 / a) V V 5 = (1 / a) V V 3 = (1-2 / a Although V V ₆ = 0, V ₁ -V ₆ may be increased or decreased by a fixed voltage value, since the voltage averaging method only requires that the difference between the voltages satisfies this relationship. .

In this embodiment, it had a configuration to obtain an optimum correction voltage using the brightness adjustment voltage V _LCD for setting a driving voltage, a driving voltage of the liquid crystal panel (1-1 / a) V, ( 1 −2
/ a) A configuration using a voltage such as V may be used.

Further, in the above-described embodiment, “ON” is displayed in the “ON” display data.
The explanation has been given using a liquid crystal display device corresponding to the display as an example,
For a liquid crystal display device that corresponds to “ON” display data with “dark” display, the “bright” display description is changed to “dark” display and the “dark” display
The same description can be applied by replacing the display description with “bright” display. [Effects of the Invention] As described above, according to the present invention, in a simple matrix type liquid crystal display device, luminance unevenness depending on a display pattern is obtained. Can be prevented even if the brightness adjustment voltage is changed.
There is an effect that high quality display can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the principle of the method of the present invention, FIG. 2 is a circuit diagram showing the structure of a first embodiment of the present invention, and FIG. 3 shows the structure of a second embodiment of the present invention. 4 (a) and 4 (b) are characteristic diagrams showing the effects of the embodiment shown in FIGS. 2 and 3, and FIG. 5 is a diagram for explaining a conventional first crosstalk.
(A) is an example of a display pattern, (b) is T-
FIG. 6 is a graph for explaining the second conventional crosstalk.
(A) is an example of a display pattern, (b) is T-
7 to 9 are diagrams showing the configuration of a luminance adjustment voltage conversion circuit for explaining another embodiment of the present invention, FIG. 10 is a diagram showing a correction characteristic when the panel temperature changes, and FIG. FIG. 12 is a diagram showing drive voltage waveforms of cells α and β in the figure, FIG. 12 is a diagram showing an example of a display pattern on a liquid crystal panel, and FIG. 13 is a diagram showing a voltage averaging method. 21: Data electrode driver, 22: Scan electrode driver, 23: Liquid crystal panel, 24: Power supply circuit, 26: Liquid crystal panel control device, 27: Correction parameter generation circuit, 28: D / A conversion circuit , 29, 32, 70, 80, 90… correction voltage addition circuit, 30… brightness adjustment volume, 31… brightness adjustment voltage conversion circuit, 271… data latch circuit, 272… data detection circuit, 273… Counter, 291,293,321,323 ... Addition circuit, 272,322 ... Inversion circuit, 312 ... Adjustment volume.

Continuation of the front page (72) Inventor Hisashi Yamaguchi 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-3-253818 (JP, A) JP-A-2-187789 (JP, A) JP-A-2-178623 (JP, A) JP-A-2-63293 (JP, A) JP-A-1-266514 (JP, A) JP-A-64-48039 (JP, A) (58) Survey Field (Int.Cl. ⁶ , DB name) G09G 3/36 G09G 3/20 G02F 1/133 505

Claims (5)

(57) [Claims] A matrix type liquid crystal panel provided with data electrodes and scan electrodes crossing each other is driven by a voltage averaging method having a positive voltage application mode period and a negative voltage application mode period, and one scan electrode drive time Each time, a correction voltage corresponding to the data displayed on the selected scan electrode is applied with a polarity opposite to that of the positive voltage application mode period and the negative voltage application mode period.
A method of driving a liquid crystal panel, wherein the correction voltage is changed according to the magnitude of the driving voltage of the liquid crystal panel, wherein the driving voltage is added to the selection voltage of the scan electrode. A matrix-type liquid crystal panel provided with data electrodes and scan electrodes intersecting each other is driven by a voltage averaging method having a positive voltage application mode period and a negative voltage application mode period, and one scan electrode driving time. Each time, a correction voltage corresponding to the data displayed on the selected scan electrode is applied with a polarity opposite to that of the positive voltage application mode period and the negative voltage application mode period.
In a driving method for adding a selection voltage of a data electrode, a non-selection voltage of a data electrode, and a non-selection voltage of a scan electrode, the correction voltage is changed according to the magnitude of the driving voltage of the liquid crystal panel. Drive method. 3. A matrix-type liquid crystal panel provided with data electrodes and scan electrodes intersecting each other is driven by a voltage averaging method having a positive voltage application mode period and a negative voltage application mode period, and one scan electrode driving time. Each time, a correction voltage corresponding to the data displayed on the selected scan electrode is applied with a polarity opposite to that of the positive voltage application mode period and the negative voltage application mode period.
A drive that adds to the select voltage of the scan electrode, and has the opposite polarity to that of adding to the select voltage of the scan electrode, and adds to the select voltage of the data electrode, the non-select voltage of the data electrode, and the non-select voltage of the scan electrode. A method of driving a liquid crystal panel, wherein the correction voltage is changed according to the magnitude of the driving voltage of the liquid crystal panel. 4. A matrix type liquid crystal panel provided with data electrodes and scan electrodes intersecting each other is driven by a voltage averaging method having a positive voltage application mode period and a negative voltage application mode period, and one scan electrode driving time. Each time, a correction voltage corresponding to the data displayed on the selected scan electrode is applied with a polarity opposite to that of the positive voltage application mode period and the negative voltage application mode period.
A driving method for adding a non-selection voltage of a scan electrode, wherein the correction voltage is changed according to the magnitude of the driving voltage of the liquid crystal panel. 5. A method of driving a matrix type liquid crystal panel having a data electrode and a scan electrode crossing each other by a voltage averaging method having a positive voltage application mode period and a negative voltage application mode period, wherein one scan electrode driving time Each time, a correction voltage corresponding to the data displayed on the selected scan electrode is applied with a polarity opposite to that of the positive voltage application mode period and the negative voltage application mode period.
A driving method for adding a selection voltage of a data electrode and a non-selection voltage of a data electrode, wherein the correction voltage is changed according to the magnitude of the driving voltage of the liquid crystal panel.