JP2001059959A - Drive method for liquid crystal device and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high display quality gradation display with less cross talk and flickers even in the gradation display of rapid response by selecting simultaneously and successively plural scanning electrodes and applying voltage divided plural times in a period of one frame to the electrodes. SOLUTION: When four lines of scanning electrodes are selected simultaneously, a voltage level of the same effective value as the voltage level that a signal electrode driving a pixel displaying a background selects is selected even in the signal electrode driving the pixel displaying the gradation display. The 1/3 gradation is displayed on the pixels of intersected points between the scanning electrodes from X5 to Xn and the signal electrodes from Y2 to Y5, and the 3/3 gradation is displayed on the pixels excepting them. A voltage waveform applied to the signal electrode Y1 driving the pixel of the 3/3 gradation of the background display selects the voltage level of -V2 for a 1F period, and becomes the waveform selecting V2 for a 2F period. When the 1/3 gradation is displayed by using a gradation pattern, the voltage waveform applied to the signal electrode Y2 becomes the waveform selecting the voltage level of either V2 or -V2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method for a liquid crystal display panel and the like and a display device using the same, and more particularly to a driving method and a display device for performing frame gradation display.

[0002]

2. Description of the Related Art As a conventional driving method of a liquid crystal element or the like, a method of sequentially selecting and driving a plurality of scanning electrodes simultaneously has been proposed (for example, A GENERALIZED ADDRESSING TEC).
HNIQUE FOR RMS RESUPONDING MATRIX LCDS, 1988 INTERN
ATIONAL DISPLAY RESEARCH CONFERENCE See pages 80-85,
Japanese Patent Application No. 4-84007, JP-A-5-46127).

As an example of such a driving method, a case where a simple matrix type liquid crystal display device as shown in FIG. 13 is driven by a method of simultaneously selecting four lines will be described.
Select four scanning electrodes at a time and select three levels (V1 or zero-
One of the voltage levels V1) is selected and applied to the scan electrodes. FIG. 14A shows a voltage waveform applied to the scan electrodes X1 to X6. At this time, the scanning pattern and the display pattern are compared, and the voltage level applied to each signal electrode is determined based on the number of mismatches. The scanning pattern is such that the selection voltage is V
The display pattern is defined as + when the voltage is 1 and − when the selection voltage is −V 1, and the display pattern is defined as + when the voltage is on and − when the voltage is off. The procedure for determining the voltage level to be applied to the signal electrode will be described below.

[0004] When the full screen ON display is performed, FIG.
The scanning pattern of the four lines (X1 to X4) selected in 1H of the first field is ++-++, and the display pattern is from + ON to ++++. When compared in order, there is a third portion having the same polarity, which is not the same, that is, the number of mismatches is one. If the number of mismatches is 1,
Among the five voltage levels (V3, V2, zero, -V2, and -V3), -V2 is selected.

[0005] In addition, when the number of mismatches is 0, -V3 is set, when the number of mismatches is 2, zero is set.
If the number of mismatches is 4, V3 is selected. Each voltage ratio is
V2: V3 = 1: 2.

When the voltage level to be applied to the signal electrode Y1 when the entire screen is turned on is determined according to the above procedure, FIG.
As shown in (b), the frame period 1F is all -V2
Is selected as the voltage waveform. Since the polarities of the scan electrodes in the next frame period are all inverted by the voltage alternating method, all the frame periods 2F have a voltage waveform that selects V2.

FIG. 14 (c) shows a voltage waveform applied to the pixel at the intersection of X1 and Y1. Due to this voltage waveform, the optical response of the pixel at the intersection of X1 and Y1 when the entire screen is on is such that the transmittance regularly repeats up and down in each field as shown in FIG. The optical response of the pixels X1 and Y1 in the case of the full-off display is such that although the transmittance slightly increases during the period when the voltage is applied to the scanning electrodes as shown in FIG. Achieves high contrast.

Further, as a method of displaying gradation, FRC (Fla
me Rate Control) is known. Binary drive IC
This is a method of displaying a gradation, and the display is turned on and off in units of frames as shown in FIG. In the case of FIG. 16, four gradation display can be performed in units of three frames. However, if it is applied to all pixels as it is, flicker occurs. For this reason, a basic pattern that normally includes 3 × 3 pixels as one set as shown in FIG. 17 is considered. If only three of the nine pixels are turned on, if one pixel is smaller than the resolution of the human eye, a human will see a display of 3/9 = 1/3 gradation. Similarly, when six of the nine pixels are turned on, a display of 6/9 = ２ gradation is performed.

Hereinafter, the applied voltage waveform in the case of gradation display and the optical response in that case will be described.

As shown in FIG. 4, a 1/3 gray scale display is displayed at the pixel at the intersection of the scanning electrodes X5 to Xn and the signal electrodes Y2 to Y5, and the other pixels are 3/3 gray scale (background). White pixel)
Is displayed. The FRC gray scale displays 3 × 3 pixels in FIG. 17 as a basic pattern.

FIG. 18A shows a voltage waveform applied to the pixel at the intersection of the scanning electrode X1 and the signal electrode Y2 in this case. The optical response is shown in FIG.

FIG. 18A shows that the voltage of the signal electrode is -V2.
And V2 as well as zero, -V3, and V3. Therefore, the optical response of FIG.
-V3 than the field period where only 2 and V2 are selected
And the transmittance during the field period where V3 is selected,
In the field period where the drop is gentle and zero is selected, the transmittance drops sharply. In the field period in which -V3 or V3 is selected, the transmittance in the off state increases, and the off display is brighter than the normal off display. For this reason, the pixel at the intersection of X1 and Y2, Y3, Y4.
Since the optical response differs from that of the pixel at the intersection of Y1 and Y1, crosstalk is observed.

[0013]

As described above, when the gray scale is displayed by the FRC method, since the voltage waveform of each signal electrode is different, the optical response is different, and the gray scale display part and the non-gray scale display part are crossed. There is a problem that a talk occurs. This is particularly remarkable when driving a liquid crystal having a high response speed.

[0014]

A plurality of scanning electrodes are simultaneously selected sequentially, and a voltage is applied to the selection electrodes in a plurality of times within one frame period, and the voltages are applied to signal electrodes for gradation display. The voltage waveform and the voltage waveform applied to the signal electrode to be displayed in the background are set to have a waveform that selects a set of voltages having the same level, and the gradation pattern to be displayed is changed every scanning period.

Further, in a display device for performing a desired display by multiplex-driving a liquid crystal element or the like having a liquid crystal interposed between a substrate having a scanning electrode and a substrate having a signal electrode, the above-described method of driving the liquid crystal element and the like It is characterized by having.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a driving method and a display method of a liquid crystal element and the like according to the present invention will be specifically described based on examples. (Embodiment 1) In Embodiment 1, when four lines of scanning electrodes are simultaneously selected, a voltage level having the same effective value as a voltage level selected by a signal electrode for driving a pixel for displaying a background is displayed by gradation. The selection is also made for the signal electrodes that drive the pixels to be displayed.

It is assumed that the liquid crystal display having the structure shown in FIG. 13 is driven. FIG. 1A shows a voltage waveform applied to scan electrodes X1 to X6 when four lines are simultaneously driven, and FIG.
Shows a voltage waveform applied to the signal electrode Y1 for driving the pixel for background display, and (c) shows a voltage waveform applied to the signal electrode Y2 for driving the pixel displaying the gray scale. FIG.
FIG. 4 is a basic pattern diagram of FRC gray scale with a basic unit of 3 × 4 pixels configured so that two pixels are always turned on or off as a group, out of four pixels selected simultaneously. FIG.
Indicates the optical response of the pixel at the intersection of the signal electrode Y2 and the scanning electrode X1.

As shown in FIG. 4, the pixel at the intersection of the scanning electrodes X5 to Xn and the signal electrodes Y2 to Y5 displays 1/3 gray scale, and the other pixels display 3/3 gray scale (white background). Pixel). The voltage waveform shown in FIG. 1A is applied to the scan electrodes X1 to X4. Here, 1F and 2F are frame periods, 1f, 2f, 3f and 4f are field periods obtained by dividing one frame period into four, and 1H is a scanning electrode X.
The scanning period 2H for selecting four lines from 1 to X4 is the scanning period for selecting four lines from the scanning electrodes X5 to X8.

As described in the conventional example, the voltage waveform applied to the signal electrode Y1 for driving the pixel of 3/3 gradation of the background display is -V2 in the 1F period as shown in FIG.
, And the waveform becomes V2 in the 2F period. When 1/3 gradation is displayed by using the gradation pattern of FIG. 2, the voltage waveform applied to the signal electrode Y2 is as shown in FIG.
As shown in (c), the waveform selects a voltage level of either V2 or -V2.

The voltage waveform of the signal electrode when displaying 1/3 gradation will be described in detail with reference to Table 1.

Table 1 shows the number of mismatches in all combinations of the scanning pattern and the display pattern for displaying 1/3 gradation, and the selection potential. The scanning pattern displays the voltage V1 selected by the scanning electrode as + and -V1 as-, and the display pattern displays ON as + and OFF as-.
When the voltage level is determined based on the number of mismatches between the scanning pattern and the display pattern according to the procedure described in the conventional example, only V2 or -V2 is selected in all combinations of the scanning pattern and the gradation pattern. V2 and -V2 differ only in polarity, and the effective voltage applied to the liquid crystal element functions exactly the same during the non-selection period. In the non-selection period, V3,
Since V3 and zero voltage are not selected, the optical response of the pixel at the intersection of the signal electrodes Y2 and X1 with the gradation display portion is shown in FIG. 3. The pixel at the intersection of the signal electrodes Y1 and X1 displaying only the background is shown in FIG. 15 (FIG. 15) and no crosstalk occurs.

[0022]

[Table 1] Table 2 shows the number of mismatches in all combinations of the scanning pattern and the display pattern in the case of 2/3 gradation display, and the selection potential. Only V2 or -V2 is selected in all combinations. In other words, even in the case of 2/3 gradation, the optical response of the pixel displaying the background on the signal electrode having the gradation display portion is the same as the optical response of the pixel on the signal electrode displaying only the background, and the crosstalk occurs. Does not occur. Similarly, even when the background is entirely black, by performing gradation display using the basic pattern of the FRC gradation shown in FIG. 2, it is possible to perform good gradation display without crosstalk.

[0023]

[Table 2] FIG. 5 shows a basic pattern of gradation display having the same effect.
Shown in In the drawing, a pattern displayed in the first frame of 1/3 gradation is shown as a representative. Of the four pixels selected at the same time, turning on and off as a set of two pixels remains the same, but FIGS. 11A and 11B show two pixels in a set adjacent to each other. ) And (d) are a combination of the case of adjacent and the case of distant.

(Embodiment 2) In the first embodiment, when displaying at 1/3 gradation or 2/3 gradation, the case where all the columns are turned on or off is included. For this reason, a flicker is noticeable when a line in which all the lines are turned on or off moves in the gradation display portion. In the second embodiment, when four lines of scan electrodes are selected simultaneously, the scan period (1H period)
This flicker is eliminated by changing the gradation display pattern every time.

FIG. 6 shows a basic pattern in the case of 1/3 gradation display repeated at a cycle of every three scanning periods (3H periods). The pattern configuration is in 3 × 12 pixel units. Four pixels are displayed for each scanning period, but three different gradation display patterns are combined for each scanning period. Specifically, the pixel display on one column of the first frame is (on, off, on, off), (off,
ON, OFF, ON) and (OFF, OFF, OFF, OFF).
The pattern of three rows is arranged in order. As shown in Table 1, the scanning pattern and the gradation display pattern select only the voltage level of V2 or -V2 in all the combinations. Therefore, even in the case of the gradation display pattern shown in FIG. Or -V2 only. For this reason, display without crosstalk due to different optical responses is possible.

In addition, when the display as shown in FIG.
Since the number of switching between 2 and -V2 becomes the same for each signal electrode and the direction of the potential change that switches between them is different, there is an effect of correcting the voltage by the canceling effect. FIG. 7 shows voltage waveforms applied to the signal electrodes Y1, Y2, and Y3 when 1/3 gradation is displayed on the entire screen of the display device shown in FIG. 13 by the pattern of FIG. Always 1 when rising and falling are the same
You can see that there are pairs. For this reason, the distortion due to the rising edge of the waveform and the distortion due to the falling edge cancel each other, and the effect of correcting the effective value voltage applied to the liquid crystal can display a halftone with high quality.

(Embodiment 3) Embodiment 3 is an example of the present invention in which six lines are simultaneously selected. In the case of simultaneous selection of six lines, a total of seven voltage levels (V2, V3, V4, zero, -V2, -V3, and -V4 levels) are required to be applied to the signal electrodes. The voltage ratio is V2: V3: V4 = 1:
2: 3. FIG. 8A shows a voltage waveform applied to the scan electrodes X1 to X6. In the display device of FIG. 12, one pixel is set at the intersection of the scanning electrodes X7 to Xn and the signal electrodes Y2 to Y5.
/ 3 gradations are displayed, and the other pixels display 3/3 gradations (white pixels on the background). The voltage waveform applied to the signal electrode Y1 for displaying white (3/3 gradation) on the entire surface has a maximum voltage level (V4) and a minimum voltage level (-V) as shown in FIG.
4) The waveform is not selected. FIG. 9 shows a basic pattern in the case of displaying four gradations. 1/3 gradation is displayed with this basic pattern. As shown in FIG. 8C, the voltage waveform of the signal electrode Y2 for displaying 1/3 gradation is a waveform in which the highest voltage level (V4) and the lowest voltage level (-V4) are not selected. That is, the voltage waveform applied to the signal electrode is V2, V3,
Only a set of five levels of zero, -V2 and -V3 is used.
Therefore, as in the first embodiment, crosstalk due to a difference in optical response does not occur. Similarly, no crosstalk occurs in the case of 2/3 gradation. Also, as in the second embodiment, it is apparent that by exchanging the basic pattern every 3H, it is possible to prevent the flicker of the gradation display and correct the distortion of the waveform, thereby performing a good gradation display. It is.

(Embodiment 4) Embodiment 4 is an example of the present invention in which five lines are selected simultaneously. In the case of simultaneous selection of five lines, a total of six voltage levels (V2, V3, V4, -V2, -V3, -V4 levels) are required to be applied to the signal electrodes. The voltage ratio is V2: V3: V4 = 1: 3:
5 The voltage waveform applied to the scan electrodes X1 to X5 is as shown in FIG. The pixel at the intersection of the scanning electrodes X6 to Xn and the signal electrodes Y2 to Y5 of the display device of FIG.
The gray scale is displayed, and the other pixels display 3/3 gray scale (white pixel on the background). Signal electrode Y1 for 3/3 gradation display
Is a waveform in which the highest voltage level (V4) and the lowest voltage level (-V4) are not selected, as shown in FIG. FIG. 11 shows a basic pattern when performing 1/3 gradation display. When a 1/3 gradation is displayed by this basic pattern, a waveform in which the highest voltage level (V4) and the lowest voltage level (-V4) are not selected as shown in FIG. In other words, the voltage waveform applied to the signal electrode is V2, V3,-
Only a set of four levels V2 and -V3 is used. Therefore, as in the first and third embodiments, crosstalk due to a difference in optical response does not occur. Also, as in the second embodiment,
It is clear that by exchanging the basic pattern every 3H, it is possible to prevent flickering of the gradation display, and to correct the distortion of the waveform, thereby achieving a good gradation display.

As described above, the same set of voltage levels as the set of voltage levels selected by the signal electrodes for driving the pixels for displaying the background are also selected for the signal electrodes for driving the pixels for displaying the gray scale display. Thus, the optical response becomes the same, and no crosstalk occurs. Further, by changing the gradation pattern for each scanning period, it is possible to set the voltage waveform applied to the signal electrode to the same number at the same position at the rise and fall. By this canceling effect, good gradation display is possible.

FIG. 12 shows a scanning pattern and a gradation display pattern when seven lines are selected. FIG. 1A is a diagram simply showing a scanning pattern by + and-signs, and FIG. 2B is a diagram showing a basic pattern of 3 × 7 pixels displaying ３ gradation. It is. The same effect as in the case of 5 or 6 lines is obtained.

In the above embodiment, four lines, five lines,
Although the case of six lines and seven lines has been described, the selection line is not limited to this, and the same concept can be used for simultaneous selection of eight or more lines.

By using the display device according to the driving method of the present invention as a display device of a personal computer or the like, it is possible to realize an easy-to-view display with improved image quality.

[0033]

As described above, when the liquid crystal is driven by the liquid crystal driving method of the present invention, a display device capable of displaying a high-quality gradation display with little crosstalk and flicker even in a high-speed response gradation display of a liquid crystal display. Can be provided.

[Brief description of the drawings]

FIG. 1 is a driving waveform diagram showing one embodiment of a driving method of a liquid crystal element or the like according to the present invention.

FIG. 2 is a diagram showing a gradation display pattern in a method for driving a liquid crystal element or the like according to the present invention.

FIG. 3 is a diagram showing an optical response.

FIG. 4 is an explanatory diagram of a display pattern.

FIG. 5 is a diagram showing another example of a gradation display pattern in a method for driving a liquid crystal element or the like according to the present invention.

FIG. 6 is a diagram showing a gradation display pattern showing another embodiment of the method of driving a liquid crystal element or the like according to the present invention.

FIG. 7 is a diagram showing voltage waveforms applied to signal electrodes showing another embodiment of the method of driving a liquid crystal element or the like according to the present invention.

FIG. 8 is a driving waveform diagram showing another embodiment of a driving method of a liquid crystal element or the like according to the present invention.

FIG. 9 is a gradation pattern diagram showing another embodiment of the method for driving a liquid crystal element or the like according to the present invention.

FIG. 10 is a driving waveform diagram showing another embodiment of a driving method of a liquid crystal element or the like according to the present invention.

FIG. 11 is a gradation pattern diagram showing another embodiment of the method for driving a liquid crystal element or the like according to the present invention.

FIG. 12 is a scanning pattern and a gradation pattern diagram showing another embodiment of the method for driving a liquid crystal element or the like according to the present invention.

FIG. 13 illustrates a structure of a liquid crystal display device.

FIG. 14 is a driving waveform diagram showing a conventional driving method.

FIG. 15 is a diagram showing an optical response at the time of background display by a conventional driving method.

FIG. 16 is an explanatory diagram of a conventional FRC gray scale display.

FIG. 17 is a basic pattern diagram of a conventional FRC gradation display.

FIG. 18 is a diagram showing an optical response at the time of gradation display by a conventional driving method.

[Explanation of symbols]

 X1, X2 to Xn scan electrode Y1, Y2 to Ym signal electrode 1F, 2F Frame period 1f, 2f Field period 1H, 2H, 3H Scan period

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 31, 2000 (2007.3.
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Patent application title: Driving method of liquid crystal device and display device

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

[0014]

According to the present invention, there is provided a method of driving a liquid crystal device, comprising: a plurality of scan electrodes; a plurality of signal electrodes intersecting the plurality of scan electrodes; and a plurality of scan electrodes and a plurality of data electrodes. In a driving method of a liquid crystal device including a liquid crystal interposed between the plurality of scanning electrodes, one display dot is represented using a set of a plurality of pixels as a basic unit, and a plurality of the scanning electrodes are divided into subgroups every h lines. Are simultaneously selected, and the selection voltage for selecting the scan electrodes is a first voltage.
Having a selected value and a second selected value, applying a signal voltage to the signal electrode based on the display data and the selected value of the selected voltage, and displaying the display state in the basic unit and the selected value in the signal voltage. Is set so that the absolute value of is constant, and the display state in the basic unit corresponding to the gradation to be displayed is changed in frame units. Further, in a method for driving a liquid crystal device including a plurality of scan electrodes and a plurality of signal electrodes intersecting the plurality of scan electrodes, and a liquid crystal sandwiched between each of the scan electrodes and each of the data electrodes, A set of pixels is represented as a basic unit to represent one display dot, a plurality of the scan electrodes are divided into sub-groups every h lines, the scan electrodes in the sub-group are simultaneously selected, and the selection voltage for selecting the scan electrodes is: Having a first selection value and a second selection value, applying a signal voltage to the signal electrode based on the display data and the selection value of the selection voltage, and the number of levels of the signal potential applied to the signal electrode is: The voltage value is set so that the same set of signal potentials is used for displaying the first gray scale and for displaying the second gray scale, which are smaller than the number of levels of all possible signal potentials. Display status in unit And sets the fine said selection value.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

Further, the display device of the present invention comprises a plurality of scanning electrodes, a plurality of signal electrodes intersecting the plurality of scanning electrodes, and a liquid crystal sandwiched between each of the scanning electrodes and each of the data electrodes. In the display device provided, a display dot is represented by using a set of a plurality of pixels as a basic unit, a plurality of the scan electrodes are divided into subgroups every h lines, and the scan electrodes in the subgroup are simultaneously selected, and the scan is performed. A selection voltage for selecting an electrode has a first selection value and a second selection value, and a signal voltage is applied to the signal electrode based on display data and a selection value of the selection voltage, and a display in the basic unit is performed. The state and the selected value are set so that the absolute value of the signal voltage is constant, and the display state in the basic unit corresponding to the gray level to be displayed is changed in frame units. In a display device including a plurality of scan electrodes and a plurality of signal electrodes intersecting the plurality of scan electrodes, and a liquid crystal sandwiched between each of the scan electrodes and each of the data electrodes, an aggregation of a plurality of pixels is provided. Represents one display dot as a basic unit, a plurality of the scanning electrodes are divided into subgroups every h lines, and the scanning electrodes in the subgroup are simultaneously selected, and the selection voltage for selecting the scanning electrodes is a first voltage. A signal voltage is applied to the signal electrode based on the display data and the selected value of the selection voltage, and the number of levels of the signal potential applied to the signal electrode is:
The voltage value is set so that the same set of signal potentials is used for displaying the first gray scale and for displaying the second gray scale, which are smaller than the number of levels of all possible signal potentials. The display state in the unit and the selection value are set.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/20 642 G09G 3/20 642D 3/36 3/36

Claims (5)

[Claims] In a driving method of a liquid crystal element or the like for multiplex driving a display element having a liquid crystal or the like between a substrate having a scanning electrode and a substrate having a signal electrode, a plurality of scanning electrodes are simultaneously selected sequentially. And a method of driving a liquid crystal element or the like, wherein the selection period is applied a plurality of times in one frame period. 2. A gradation method for displaying gradation by displaying ON or OFF for each frame, wherein a voltage waveform applied to a signal electrode for displaying gradation and a voltage waveform applied to a signal electrode for displaying background are the same. 2. The method according to claim 1, wherein the waveform is a waveform for selecting a set of voltage levels. 3. A gradation method for displaying gradation by displaying ON or OFF for each frame, wherein a voltage waveform applied to a signal electrode for displaying gradation and a voltage waveform applied to a signal electrode for displaying background are the same. 2. The method of driving a liquid crystal element or the like according to claim 1, wherein a waveform for selecting a set of voltage levels is set as a waveform, and a gradation pattern to be displayed is changed for each scanning period. 4. A method for simultaneously selecting a plurality of scanning electrodes simultaneously by sequentially selecting a plurality of scanning electrodes from a liquid crystal element having a liquid crystal or the like interposed between a substrate having scanning electrodes and a substrate having signal electrodes, and selecting the period for one frame period. When a display device such as a liquid crystal element by a driving method of applying a voltage in a plurality of times is displayed on or off for each frame to display a gray scale, the display device is applied to a signal electrode for displaying a gray scale. A display device comprising a liquid crystal element or the like which is driven by a waveform in which a voltage waveform and a voltage waveform applied to a signal electrode for background display select a set of voltages having the same level. 5. A method for simultaneously selecting a plurality of scanning electrodes simultaneously by sequentially selecting a plurality of scanning electrodes from a liquid crystal element or the like having a liquid crystal or the like interposed between a substrate having scanning electrodes and a substrate having signal electrodes, and selecting the period for one frame period. In a case where a display device such as a liquid crystal element by a driving method of applying a voltage in a plurality of times is displayed on or off for each frame to display a gray scale, a voltage is applied to a signal electrode of a gray scale display portion. And a liquid crystal element driven by changing a gradation pattern to be displayed for each scanning period. A display device, characterized in that: