JPH0887000A - Display device - Google Patents

Abstract

PURPOSE: To attain a display without a flicker and with high definiton. CONSTITUTION: In a display device performing interlace scanning successively inpressing selection signals MA-MC to respective scan electrodes while jumping at least one piece of scan electrode and partially rewriting scanning rewriting the partial display on the display panel by successive scanning on a display panel constituting pixels in matrix by scan electrode group S1-S9 and information electrode groups, dummy singnals Ma-Mc temporarily fluctuating the transmission light quantity of the pixel corresponding to the scan electrode are impressed to at least one piece of the scan electrodes existing in a non-selection state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly to an image display device by arranging scanning electrodes (scanning signal lines) and information electrodes (information signal lines) in a matrix and applying and driving scanning signals and information signals respectively. Alternatively, the present invention relates to a display device which displays an image.

[0002]

2. Description of the Related Art Conventionally, as a display device of a television receiver, a personal computer (hereinafter abbreviated as PC) or a work station (hereinafter abbreviated as WS), a CRT (Ca
the Thode Ray Tube) has been used. Note that the television receiver uses an interlace system with a field frequency of 60 Hz and a frame frequency of 30 Hz in order to display moving images by radio waves with a simple driving device. The field frequency of 60 Hz is a frequency necessary to prevent flicker (flicker due to a difference in brightness in the image). In the case of PC or WS, a frame frequency of 60 Hz or higher is used, and a progressive scanning method is adopted to improve the visibility of moving display of a mouse, an icon and the like.

In recent years, TN (Twisted)
nematic) and STN (Super Twist)
A liquid crystal display device having a d nematic structure or the like will be used for an in-vehicle television receiver, a navigation display device, a video camera playback display device, a laptop PC, etc. due to its advantages of light weight, thin shape and power saving. Is becoming. Since these display devices including plasma display devices other than the above do not have a memory property, they are sequentially scanned at a frame frequency of 60 Hz or higher.

On the other hand, in such a situation, Japanese Patent Laid-Open No. 56-107 was published by both Clarc and Lagerwall.
The display device having ferroelectricity proposed in Japanese Patent No. 216, U.S. Pat. No. 4,367,924 and the like has a memory property of image information, and therefore the number of scanning lines is larger than that of the display device. Can be increased, and high-definition display is possible. However, in order to use it as a display device of a man-machine interface, a decrease in frame frequency becomes a problem, due to an increase in scanning time in proportion to the high-definition display.

As a proposal for this problem, there is a partial rewriting scan (Kanbe et al., US Pat. No. 4,655,561) which preferentially drives a scanning line with changed image information. A frame rate improving method called "multi-interlaced scanning + partial rewriting scanning" is proposed in Japanese Patent Laid-Open No. 63-65494 of Katakura et al.

Further, by applying a dummy signal to at least one of the scanning lines in the non-selected state to temporarily change the display state of the pixel corresponding to the scanning line, the flicker phenomenon due to the lowering of the frame frequency is prevented. Prevention is proposed in Japanese Patent Application Laid-Open No. 6-18853 by Okada et al.

[0007]

When the problem of frame frequency reduction is considered from the viewpoint of flicker, the flicker recognition state differs depending on whether the display device has a memory property or the scanning method. Specifically, the frame frequency at which flicker is not recognized in a ferroelectric liquid crystal display device having a memory property is 40 Hz when sequential scanning is performed.
The above is necessary.

Even when multi-interlaced scanning is used, the scanning time interval for each line is long and some screen flicker remains. Further, when multi-interlace is used, the display of the moving point on the screen is scattered, so that it is necessary to perform the partial rewriting scanning in which that portion is preferentially written.

Furthermore, the flicker phenomenon is what the human visual sense recognizes the change in the light quantity of the information writing portion in the screen, and the degree of recognition changes depending on the relationship between the lightness and darkness of the entire screen and the lightness and darkness of the written information. . For example, in the case of a ferroelectric liquid crystal, a scanning method is known in which writing is performed after erasing in order to effectively use the memory property.
In this case, the method of recognizing flicker differs depending on whether writing is performed after black erasing or writing is performed after white erasing. In fact, the latter, in which the screen is dark and the image is erased, gives more flicker.

In the actual driving of the ferroelectric liquid crystal, there is an example in which the selection time of one scanning line is about 100 μs, and when writing information line-sequentially on a panel having 1024 scanning lines, the frame frequency is 9. It is 6 Hz. At this time, the panel
Flicker will be recognized. To avoid this, multi-interlaced scanning is necessary, but as described above, it is necessary to increase the scanning frequency for each line at the same time.

In gradation display, driving for inverting the selective scanning waveform every 1H may be used, and since black erasing writing and white erasing writing are present in one screen, the flicker causes the above condition. It becomes easier to be recognized.

The present invention has been made in view of the above-mentioned flicker generation conditions, and an object of the present invention is to provide a display device in which flicker is difficult to recognize and display quality is high.

[0013]

In order to achieve the above-mentioned object, in the present invention, in consideration of the above-mentioned flicker generation condition, the amount of light transmitted through a pixel is temporarily set to at least one of the scanning lines in the non-selected state. By using the dummy scanning which is changed to the above together with various writing scanning, the occurrence of flicker is suppressed.

For example, one horizontal scanning period in the above example is 100
In the case of μs, if a plurality of selective scans and dummy scans are used together and the dummy scan waveform voltage is appropriately set, flicker is hardly recognized.

Considering a case in which multi-interlacing for speeding up the television image reception and moving image updating speed and dummy scanning are newly used, it is preferable that the intervals between the selective scanning and the dummy scanning are equal. This is because the dummy scanning has a function of temporarily increasing the amount of transmitted light around the writing scanning and suppressing flicker by visually averaging the amount of transmitted light. Therefore, if the interlace width of the dummy scan is the same as the interlace width of the selective scan, the flicker suppressing effect is greater.

In the combined use of the partial rewriting scanning and the dummy scanning, it is preferable to perform the dummy scanning at the same scanning interval as the scanning interval for performing the partial rewriting scanning for the above reason.

When multi-interlaced scanning is used, it is preferable to use partial rewriting scanning in combination to prevent the movement points from being scattered. In this case, the scanning by the dummy signal is preferably switched between the interlaced scanning and the partial rewriting in the case of multi-interlacing.

At this time, the frame frequency is basically lower in the partial rewriting scanning, so that the absolute value of the voltage of the dummy scanning waveform at this time is increased or the number of dummy scannings is increased to increase the amount of transmitted light. It is possible to compensate for the degradation.

Further, in order to suppress the bright flicker on the dark screen due to the 1H inversion of the scanning waveform, the optimum condition is set by increasing the absolute value of the voltage of the dummy scanning waveform or increasing the number of dummy scanning lines to increase the amount of transmitted light. Exists. Therefore, when the selection signal is multi-interlaced scanning, or
The light amount of the dummy signal inserted during the partial rewriting scanning needs to be adjusted by changing the above parameters according to the erasing and writing method of the selection signal.

[0020]

In general, the scanning of the display device is intended to be written and held for a sufficient time to visually recognize the amount of transmitted light of the target pixel such as writing or erasing image information (belonging to writing). Therefore, the number of scanning lines that are simultaneously scanned in one frame is one (excluding screen split driving, simultaneous writing of a plurality of lines, etc.). Therefore, conventionally,
When one brightness change is visually averaged with respect to the area of the entire display screen, the brightness change is displayed at such a high speed that it cannot be recognized.

However, according to the present invention, when the frame frequency cannot be increased sufficiently to suppress the flicker due to the increase in the number of scanning lines of the display device or the characteristics of the liquid crystal material, the display is performed. It is possible to suppress flicker recognition by visually averaging the changes in the brightness of the scanning within the display surface by causing the display element to temporarily fluctuate the amount of transmitted light in the screen and using it as a dummy scanning.

In the present invention, by using the above concept in combination with multi-interlaced scanning and / or partial rewriting scanning, it is possible to gradually reduce flicker while maintaining the image update speed and the suppression of display variation.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 8 shows a cross-sectional structure of a cell of a liquid crystal panel manufactured and used as an example to which the present invention is applied. The cell of FIG. 8 has glass substrates 11a and 11b on which transparent electrodes 12a and 12b forming matrix electrodes are arranged so as to face each other, and an electric field sandwiched between these substrates and applied through the matrix electrodes. Correspondingly, the ferroelectric liquid crystal 15 that can assume the first stable state and the second stable state is provided. As the liquid crystal material, chiral smectic liquid crystals (SmC *, SmH *) were used. In addition,
When the layer thickness of the liquid crystal material is large, the long axes of the liquid crystal molecules exhibit twisted orientation, and therefore the liquid crystal is arranged between layers that are thin enough (for example, 1 to 3 μm) so that twisting of the molecules does not occur.
Alignment films 14a and 14b are provided in contact with the liquid crystal 15, and these alignment films are rubbed with a cloth to align the molecules of the liquid crystal 15. This rubbing is performed by shifting the rubbing direction of the lower substrate by 190 degrees with respect to the rubbing direction of the upper substrate. Glass substrates 11a and 11b
Polarizing plates 10a and 10b are arranged in crossed Nicols outside each of them, and control the light transmitted through the liquid crystal 15 layer. In order to control the thickness of the liquid crystal layer 15 and keep it uniform, the alignment film 1
A bead spacer 16 is arranged between 4a and 14b. In addition, the alignment films 14a and 14b and the transparent electrodes 12a and 1
In order to prevent a short circuit between the transparent electrodes 12a and 12b arranged with the liquid crystal 15 layer interposed between the insulating films 13a and 1b,
3b is arranged. As shown in FIG. 9, the electrodes of the panel are composed of 1024 scanning-side electrodes S1 to S1024 and 960 information electrodes I1 to I960.

In this liquid crystal panel, a liquid crystal material 15 containing a pyrimidine component and having the characteristics shown in Table 1 was used as the ferroelectric liquid crystal material.

[0026]

[Table 1] Next, driving of the display panel will be described. The display panel is driven by using the selection signal, the information signal and the dummy signal. The selection signal is a signal for writing image information for displaying an image on a display screen for each scanning line. The signal causes a potential difference with the information signal applied to the information line. As a result, the spontaneous polarization of the liquid crystal 15 in FIG. 8 acts on the electric field, the orientation of the liquid crystal molecules is determined, and the birefringence of light caused thereby is determined by the polarizer 1.
The combination of 0b and the analyzer 10a is displayed as light and dark. As the selection signal, a method is known in which a reset signal for temporarily dark erasing or bright erasing a pixel is used in combination. Further, the information signal is a signal that determines the display state by causing a potential difference from the selection signal and changing the orientation of the liquid crystal molecules as described above. Then, for the non-selected scanning lines, a voltage is selected so that the information signal does not change the state of the pixel. Further, the dummy signal causes fluctuation of liquid crystal molecules due to the potential difference from the information signal, and temporarily changes the light transmittance. However, when the signal is removed, the liquid crystal molecules revert to their previous state. Of these signals, the voltage and waveform of the dummy signal are preferably selected as appropriate according to the voltage of the selection signal and the information signal and the characteristics of the liquid crystal material. More specifically, the waveform of the dummy signal is set so that the potential difference between the dummy signal and the information signal and the energy due to the time do not exceed the energy of the molecular inversion of the liquid crystal. The luminance change on the screen due to this scanning is visually averaged together with the luminance change of the selection signal. Therefore, the flicker can be gradually reduced at a low frame frequency by adjusting the number of simultaneous scanning lines of the dummy signal, the scanning positional relationship with the selection signal, and the mutual transmitted light amount.

As the drive waveform, a method of scanning the entire surface with the same polarity waveform (no inversion of the scanning waveform), a method of inverting the polarity every time one scanning line is scanned (1H inversion), or the like is used. In this example, the 1H inversion drive waveform shown in FIG. 10 was used. FIG. 11 shows the waveform used in the main scan. FIG.
In FIG. 1, SEL indicates a selection signal waveform, SEG indicates an information signal waveform, and DM indicates a dummy signal waveform. The selection signal waveform SEL includes a reset pulse P1 and a selection pulse P2. Also, the information signal waveform S
The EG is composed of a selection period Q1 having image information and an auxiliary period Q2 for canceling the DC component of Q1. further,
The dummy signal waveform DM is composed of an AC waveform such that no DC component remains, and is provided with a voltage and time at which the pixel information does not change due to the difference from the information signal SEG. Here, 1 Ha indicates an image information erasing period of the scanning line, and 1 Hb indicates a writing period of image information of the scanning line. Further, Δt is a period in which the selection pulses P2 and Q1 and P1 and Q2 are synchronized.

Next, a conventional example in which dummy scanning is applied to sequential scanning will be described with reference to FIGS. 12
From the scanning line S1 every horizontal scanning period (T ₁ , T ₂ , ...
..), the G waveform, the H waveform, ..., And the selection waveform is sequentially applied. Here, the G waveform and the H waveform are waveforms in which the voltage is inverted with respect to the common voltage, and the polarity of the voltage is switched for each scanning line. In the G waveform, dark erase is performed by the reset pulse, and in the H waveform, bright erase is performed. The frame frequency of this display device is 9.6 Hz, and flicker due to selective scanning is recognized. In particular, the bright erase by the H waveform causes the flicker to be strongly recognized on the dark screen. Regarding these erase waveforms, the case of the G waveform and the bright information signal is shown in FIG. The selected waveform is the G waveform, the dark information signal is the K waveform, and the composite waveform thereof is the L waveform. The L waveform is dark erased by the pulse L1 and is not written thereafter. FIG. 14 shows the case of the G waveform and the dark information signal. The selected waveform is the G waveform,
The bright information signal has an M waveform, and its composite waveform has an N waveform. With respect to the N waveform, dark erasing is performed by the pulse N1, and then bright writing is performed by the pulse N2.

FIG. 15 shows the case of H waveform and bright information signal.
Shown in The selected waveform is the H waveform, the dark information signal is the K waveform, and the composite waveform thereof is the Q waveform. With respect to the Q waveform, bright erasing is performed by the pulse Q1 and then dark writing is performed by the pulse Q2. FIG. 16 shows the case of the H waveform and the dark information signal. The selected waveform is the H waveform, the bright information signal is the M waveform, and the composite waveform thereof is the R waveform.
The R waveform is brightly erased by the pulse R1 and is not written thereafter.

It is known to use both selective scanning and dummy scanning in combination as a method for solving the problem that flicker is easily recognized when light-erasing scanning is performed on a dark screen (JP-A-6-18853). In this dummy scanning, as shown in FIG. 17, the combined waveform O of the dummy signal I and the dark information signal K does not change the pixel to the dark state or the bright state. In addition, FIG.
As shown in (1), the combined waveform P of the dummy signal I and the bright information signal M does not change the pixel to the dark state or the bright state. FIG. 19
And FIG. 20 shows the case of scanning by the inverted waveform J of the dummy signal I. In either case, the composite signal S and the composite signal T do not change the pixel to the dark or bright state.
However, none of the combined signals has the energy to change the pixel to the dark state or the bright state, but shakes the liquid crystal molecules to change the amount of transmitted light. For example, as shown in FIG. 12, if dummy scanning is started every 256 horizontal scanning periods after the selective scanning is started, T ₁ (selective scanning), T ₂₅₆
(Dummy scan), T ₅₁₂ (dummy scan) and T ₇₆₈
The four scans (dummy scan) are simultaneously performed, and the frame frequency apparently becomes 38.4 Hz. At this frame frequency, flicker is barely noticeable. However, when bright erasure is performed on a dark screen, the visual sense becomes sensitive and flicker is easily recognized.

Further, it is not preferable to use the frame frequency corresponding to the fastest reaction speed of the display panel to be used when the reaction speed of the liquid crystal changes with temperature.

In such a case, the multi-interlace scanning is performed. By using the multi-interlacing and the dummy scanning together, it is possible to reduce the flicker without using the extremely high-order interlaced scanning. Was confirmed. However, in this case, there is a problem of how to perform the dummy scanning.

Next, an embodiment of the present invention will be described with reference to FIGS.

First, an example in which multi-interlacing and dummy scanning are used together is shown. The present inventor shifts the scan start time of the dummy scan from the scan start time of the selective scan, and when the dummy scan is performed by the same interlaced scan as the selective scan, the scan can be performed without breakage, and it is also effective against flicker. I found that. The scanning method is shown in FIG. In FIG. 1, the selective scanning is performed by interlacing four MA waveforms, MB waveforms, and MC waveforms (four interlaces), and dummy scanning is also performed every 256 horizontal scanning times (T ₂₅₆ , T
₅₁₂ and T ₇₆₈ ) are interlaced with four Ma waveforms, Mb waveforms and Mc waveforms (four interlaces). In this case, the selection signal and the dummy scan do not overlap with each other, and the interlaced intervals are uniform, which is advantageous for averaging the transmitted light.

Second, an example in which partial rewriting scanning and dummy scanning are used together will be shown. As described above, when high-order interlaced scanning is used, several fields are needed to draw one event (mouse, icon, etc.) on the screen, and the display between them is scattered. In order to solve this, a method called partial rewriting scanning is used. In this scanning, rewriting of a designated event is preferentially performed by sequential scanning. However, in the main scan, one portion is scanned at a high-density scan interval, so that the frame frequency is lower than that in the multi-interlace. Therefore, also with respect to this problem, the combined use of the dummy scan and the main scan was effective in reducing the flicker. FIG. 2 shows an example in which a dummy scan is inserted after the three horizontal scans of the selective scan for ease of illustration. In this example, the case where an event to be rewritten occurs in the eleventh scanning line S11 and the twelfth scanning line S12 is shown. In this case, S11 and S12 are preferentially sequentially scanned even if the scanning line Sn not shown in FIG. 2 is scanned, and the selective scanning waveforms PA and PB are sequentially supplied to the corresponding scanning line. Accordingly, the dummy scanning waveform Pa
And Pb are also supplied to the eighth scanning line S8 and the ninth scanning line S9 during the same period. In this example, dummy scanning is inserted after three horizontal scanning periods, but it may be after 256 horizontal scanning lines or before and after any horizontal scanning. However, the effect of reducing flicker is high because the scans are evenly spaced.
In addition, it is desirable that the light amount be set so as to be averaged and fused with the transmitted light amount of the selective scanning.

Thirdly, an example in which scanning is performed by taking advantage of both the multi-interlaced scanning and the partial rewriting scanning will be described. Also in this case, considering bright erasure dark writing, etc., scanning must be performed at a considerably high frame frequency even if interlaced scanning is used. Therefore, the effect of using the dummy scanning in the interlaced scanning was also used in this example. As a result, it was possible to reduce the flicker while maintaining the advantages of both parties. FIG.
4 and FIG. 4 show how to supply the drive waveforms when the multi-interlacing is used together with the partial rewriting and the dummy scanning. First, a period in which partial rewriting is started from multi-interlace will be described with reference to FIG. In the figure, MB and MC indicate selection waveforms supplied to S4 and S7 by three-interlaced scanning, respectively. Mc is shown as a dummy waveform for scanning S4 in synchronization with MC. Where S11 and S1
Since an event to be partially rewritten occurs in No. 2, scanning by the selection waveform MC is interrupted and scanning by the selection waveforms PA and PB is started. Here, "(scan line of partial rewrite selection waveform PA) S11- (scan line of selection waveform MC by multi-interlace scanning) S7" is four scan lines, and "(final dummy waveform Mc in multi-interlace scanning period Mc Scan line) S4 + 4 scan line ”, that is, S8
Is the start position of the dummy scan at the time of partial rewriting.
Therefore, the dummy waveform Pa is supplied to S8. Further, the next dummy scan is performed at the same scan interval as the partial rewrite selection scan, and the dummy waveform Pb is supplied to S9.

Next, referring to FIG. 4, the scanning for returning from the partial rewriting scanning to the multi-interlaced scanning will be described. After partial rewriting (selective waveform PB for partial rewriting
After S12), the selection waveform MD is supplied from S7 to which the selection waveform MC is applied in order to restart the scanning of three interlaces to S10 of the third line. Further, the selection waveform ME is supplied to S13 by skipping two lines from the scanning line. The dummy scanning waveforms inserted in these interlaced scanning periods are “−2 scanning lines” “(scanning line of selection waveform MD by multi-interlaced scanning) S10− (scanning line of partial rewriting selection waveform PB) S12”. "(Scan line of final dummy waveform Pb in partial rewriting scan period) S9 + -2 scan line", that is, S7 is set as the scan start position. Then, the dummy waveform Md for scanning S7 is started, and the dummy waveforms Me, Mf for scanning S10 are skipped in the same three lines as in the selective scanning. From the above,
It is possible to use the three scanning means together. It should be noted that the present example illustrates three lines of interlacing and dummy scanning after one horizontal scanning period in order to allow illustration on a limited space, but the usage is not limited to this. FIG. 5 is an additional explanatory diagram regarding the switching of the three scanning means. Scanning lines are shown in the vertical direction, and time is shown in the horizontal direction. Here, the case of interlacing (two jumps) is shown for simplification of description. First, M2 in the Ta period
Represents selective scanning by interlacing. MD1 is used as the dummy scan used in combination with the selection. Next, in the partial rewriting period Tb, the scanning PW
Is started by sequential scanning, PD2 is used as a dummy scanning in the above procedure. PD shown during this period
1, PD3 and PD4 will be described later. Further, the interlace period Tc is restarted after Ta, and the scanning Tc starts. Here, M2 is used as a dummy scan. In this series of operations, the partial frame frequencies of Ta and Tc are twice the Tb period. Therefore, during the partial rewriting period of Tb, the T
It is more effective to use a larger number of dummy scans than the period a and Tc so that the scan interval is half of Ta and Tc, and to make the apparent frame frequency higher than in the case of one dummy scan. Further, when the number of dummy scans in the Tb period cannot be increased, the absolute value voltage with respect to the common voltage of the dummy waveform can be increased to increase the transmitted light amount per scan, or the change of the transmitted light amount per unit area can be increased. This is suitable for partial rewriting and selective scanning, which has many effects, and is effective in reducing flicker. FIG. 6 shows a graph when subjectively evaluating the flicker by changing the number of dummy scans and frequency, and FIG. 7 shows a result of subjectively evaluating the flicker when changing the voltage of the dummy waveform. Evaluation is 0-5
As the value evaluation approaches 5, flicker is less likely to be recognized. In each case, the evaluation is performed by scanning the dark screen where flicker is easily recognized.

[0038]

By performing the dummy scanning in addition to the selective scanning, a temporary fluctuation in the amount of transmitted light in the display screen is caused in the display element, thereby changing the luminance of scanning within the display surface. It is possible to visually average and suppress the recognition of flicker.

In the present invention, the above concept is used in combination with the multi-interlaced scanning and / or the partial rewriting scanning, so that the flicker can be gradually reduced while maintaining the image update speed and the suppression of the display variation.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of scanning in which dummy scanning is used in combination with multi-interlaced scanning according to the present invention.

FIG. 2 is a diagram showing an example of scanning in which dummy scanning is used in combination with partial rewriting scanning according to the present invention.

FIG. 3 and FIG. 4 are diagrams showing scan switching examples in which multi-interlaced scan is used in combination with partial rewriting and dummy scan.

FIG. 5 is a diagram for improving image quality by a dummy waveform in the case of scanning in which multi-interlaced scanning is used together with partial rewriting and dummy scanning.

FIG. 6 is a graph showing subjective evaluation of flicker when changing the number of dummy scanning lines and frame frequency in the case of progressive scanning.

FIG. 7 is a graph chart of subjective evaluation of flicker when the absolute voltage with respect to the common voltage of the dummy waveform is changed.

FIG. 8 is a sectional view of a ferroelectric liquid crystal display panel to which the present invention is applied.

9 is an electrode layout diagram of the display panel of FIG.

FIG. 10 is a waveform diagram showing an example of sequential selection scanning in which the voltage polarity with respect to the common voltage is inverted for each horizontal scanning line.

FIG. 11 is a diagram of a selective scanning waveform, an information signal waveform, and a dummy scanning waveform used in this example.

12 is a waveform diagram in which dummy scanning is used in combination with the sequential scanning of FIG.

13 is a waveform diagram showing the first scanning line selection waveform, the information signal of the dark information waveform of FIG. 12, and a composite waveform thereof.

FIG. 14 is a diagram showing the first scanning line selection waveform, the information signal of the bright information waveform of FIG. 12, and a composite waveform thereof.

FIG. 15 is a diagram showing a second scanning line selection waveform, an information signal of a dark information waveform of FIG. 12, and a composite waveform thereof.

16 is a diagram showing a second scanning line selection waveform, an information signal of a bright information waveform and their combined waveform in FIG.

FIG. 17 is a diagram showing the first scanning line dummy waveform, the information signal of the dark information waveform of FIG. 12, and their combined waveform.

FIG. 18 is a diagram showing the first scanning line dummy waveform, the information signal of the bright information waveform of FIG. 12, and a composite waveform thereof.

FIG. 19 is a diagram showing a dummy signal waveform of the second scanning line in FIG. 12, an information signal of a dark information waveform, and a composite waveform thereof.

20 is a diagram showing the second scanning line dummy waveform, the information signal of the bright information waveform of FIG. 12, and their combined waveforms.

[Explanation of symbols]

10a: analyzer polarization plate, 10b: polarizer polarization plate, 11a: glass substrate, 11b: glass substrate, 12
a: transparent electrode, 12b: transparent electrode, 13a: insulating film, 1
3b: insulating film, 14a: alignment film, 14b: alignment film, 1
5: Ferroelectric chiral smectic liquid crystal, 16: Bead spacer, 1Ha: erase period, 1Hb: selection period,
11 to 1960: information line, DM: dummy signal waveform, dt
1, dt2: period of pulses forming selected waveform, G: selected waveform, H: selected waveform, I: dummy waveform, J: dummy waveform, K: information signal waveform, L: composite waveform of selected waveform and information signal waveform , M: information signal waveform, MA: multi-interlace period selection scan waveform, MB: multi-interlace period selection scan waveform, MC: multi-interlace period selection scan waveform, MD: multi-interlace period selection scan waveform, ME: multi Interlace period selection scan waveform, M2: Interlace period selection scan, Ma: Multi-interlace period dummy scan waveform, Mb: Multi-interlace period dummy scan waveform, Mc: Multi-interlace period dummy scan waveform, Md :: Multi-interlace Period dummy scan waveform, Me: Multi
Interlace period dummy scan waveform, Mf: Multi-interlace period dummy scan waveform, MD1: Interlace period dummy scan waveform, N: Composite waveform of selected waveform and information signal waveform, O: Composite waveform of dummy waveform and information signal waveform,
P: Composite waveform of dummy waveform and information signal waveform, PA: Partial rewriting period selection scanning waveform, PB: Partial rewriting period selection scanning waveform, PW: Partial rewriting period selection scanning, Pa:
Partial rewriting period dummy scan waveform, PD1: Partial rewriting period dummy scan, PD2: Partial rewriting period dummy scan, PD3: Partial rewriting period dummy scan, PD4: Partial rewriting period dummy scan, P1: Reset pulse,
P2: selection pulse, Q: composite waveform of selection waveform and information signal waveform, Q1: selection period, Q2: auxiliary period for canceling DC component, R: combination waveform of selection waveform and information signal waveform, SE
L: selection signal waveform, SEG: information signal waveform, S1 to S1
024: scanning line, S: synthetic waveform of dummy waveform and information signal waveform, T: synthetic waveform of dummy waveform and information signal waveform, T1
To T13: horizontal scanning time, T255 to T260: horizontal scanning period, Ta: multi-interlace period, Tb: partial rewriting period, Tc: multi-interlace period,
V1, V2: Selected waveform voltage, V5, V6: Dummy waveform voltage, + VS, −VS: Information signal waveform voltage, Δt: Selected synchronization period.

Claims (9)

[Claims] 1. A display panel, in which pixels are arranged in a matrix by a scan electrode group and an information electrode group, the scan electrode of the display panel is provided with an information signal voltage while jumping over at least one scan electrode. Interlaced scanning is performed in which a first scanning signal that causes a predetermined display state to be generated in the pixel due to the difference is performed, and at the time of performing the interlaced scanning, at least 1 other than the scanning line in which the first scanning signal is being applied. A display device, comprising: scanning a book with a second scanning signal for temporarily varying the amount of transmitted light of a pixel corresponding to the scanning line with the same number of interlaces as that of the first scanning signal. 2. A display panel in which pixels are arranged in a matrix by a scanning electrode group and an information electrode group, and the preferentially selected scanning electrode of the display panel has a pixel due to a difference from an information signal voltage. When a partial rewriting scan for applying a first scanning signal for producing a predetermined display state is performed, and the partial rewriting scan is performed,
At least one scanning line other than the scanning line to which the first scanning signal is being applied has the same number of scanning intervals as the second scanning signal for temporarily varying the transmitted light amount of the pixel corresponding to the scanning line. A display device characterized in that scanning is performed while maintaining the temperature. 3. A display device, comprising means for performing scanning by switching between the interlace mode for performing interlaced scanning according to claim 1 and the partial rewriting mode for performing partial rewriting scanning according to claim 2. 4. A "partial rewriting start scanning line" in which the first scanning signal moves for partial rewriting when the interlacing mode is switched to the partial rewriting mode and the first scanning signal starts the partial rewriting. 4. The display according to claim 3, wherein the scanning of the second scanning signal is started from a scanning line position where "the number of scanning lines obtained by subtracting the previous scanning line position from the position" is added to the position of the previous second scanning signal application. apparatus. 5. When the first scan signal is switched from the partial rewrite mode to the interlace mode and the first scan signal ends the partial rewrite, the first scan signal moves for the next scan, “next scan line”. The scanning of the second scanning signal starts from a scanning line position obtained by adding "the number of scanning lines obtained by subtracting the scanning line position of partial rewriting end from the position" to the position of application of the second scanning signal at the end of partial rewriting. Item 5. The display device according to item 3. 6. The absolute voltage applied to the common voltage of the second scanning signal in the interlace mode is smaller than the absolute voltage applied to the common voltage of the second scanning signal in the partial rewriting mode. The display device according to claim 3. 7. The number of second scanning signals in one frame in the interlaced mode is less than or equal to the number of second scanning signals in one frame in the partial rewriting mode. Display device described. 8. The display device according to claim 1, wherein the pixel is made of liquid crystal. 9. The display device according to claim 8, wherein the liquid crystal is a ferroelectric liquid crystal.