WO2019080302A1

WO2019080302A1 - Display device

Info

Publication number: WO2019080302A1
Application number: PCT/CN2017/116244
Authority: WO
Inventors: 单剑锋
Original assignee: 惠科股份有限公司
Priority date: 2017-10-26
Filing date: 2017-12-14
Publication date: 2019-05-02
Also published as: CN107689222A

Abstract

A display device, comprising: a plurality of pixels arranged in a matrix form; an image signal line for providing a data signal for the plurality of pixels; a scanning signal line intersecting with the image signal line; a gate driving circuit for outputting a scanning signal to the scanning signal line and outputting the scanning signal to drive the scanning signal line; and a control circuit for controlling the gate driving circuit by means of a control signal, the control signal having a periodic waveform level that changes along with a level. The level of the scanning signal rises obliquely from a first level to a second level with a curvature of a parabola in the shape of a Chinese character "凸" when at least one scanning period of the scanning signal begins, and falls obliquely from the second level to the first level with a curvature of a parabola in the shape of a Chinese character "凹" when the at least one scanning period ends.

Description

Display device

[0001] The present application relates to a display device such as a matrix liquid crystal display (LCD) device and a display method thereof, and more particularly to a display device such as an LCD device, wherein each display pixel is provided with, for example, a thin film transistor as a switching component And its display method. Background technique

[0002] LCD devices are widely used as display devices for televisions, graphic displays, and the like. Among them, a considerable concern has been given to an LCD device in which each display pixel is equipped with a thin film transistor (hereinafter referred to as TFT) as a switching element, because such an LCD device does not generate even between adjacent display pixels. A display image in which no crosstalk occurs between adjacent display pixels, in which a case where the number of pixels is increased. A conventional LCD device includes an LCD panel as a main component, and a driving circuit portion, and the LCD panel is formed by sealing a liquid crystal composition between a pair of electrode substrates, and disposing the deflecting plate on an outer surface of the electrode substrate Formed on the top.

The TFT array substrate is formed in a matrix form of a plurality of signal lines and a plurality of scanning lines on a transparent insulating substrate, and the transparent insulating substrate may be, for example, glass. At each intersection of the signal line and the scanning line, a shut-off assembly is provided which is composed of a TFT connected to the pixel electrode and is provided with an alignment film covering all of the above components. On the other hand, the reverse substrate as the other electrode substrate is laminated by the opposite electrode and the alignment film, and the reverse substrate is almost entirely made of a transparent insulating substrate, for example, a glass substrate, and as a TFT Array substrate. The driving circuit portion is composed of a scanning signal line driving circuit, a signal line driving circuit and a reverse electrode driving circuit, which are respectively connected to the scanning line, the signal line and the opposite electrode of the panel. The control circuit is a circuit for controlling the signal line drive circuit and the scan signal line drive circuit.

[0004] In a transmission equivalent circuit in a case where a signal transmission delay of a scanning signal line is focused, a plurality of parasitic capacitances include a cross capacitance generated at an intersection of a scanning signal line and a signal line. Therefore, the scanning signal lines constitute a signal delayed transmission path. As described above, the level shift of the pixel potential due to the parasitic capacitance inside the panel is uneven in the entire display plane, and since the LCD device has a large screen and becomes higher in definition, it becomes More difficult to ignore. Therefore, the generality of the bias reverse level The solution cannot absorb the difference in level shift across the entire display plane and thus does not perform optimal AC drive with respect to each pixel. Therefore, defects such as flickering and aging residual images due to the application of the alternating component are caused.

technical problem

The technical problem to be solved by the present application is to provide a display device capable of sufficiently suppressing the occurrence of flicker or the like due to fluctuations in pixel potential, and achieving high definition and high performance.

Problem solution

Technical solution

An embodiment of the present application provides a display device including a plurality of pixels arranged in a matrix, an image signal line for providing a data signal to the plurality of pixels, and a scan signal intersecting the image signal line. a gate driving circuit that outputs a scan signal to the scan signal line and outputs a scan signal to drive the scan signal line; and a control circuit that controls the gate drive circuit by a control signal, the control The signal has a waveform level of a period accompanying the level change; wherein the start of at least one of the scan periods of the scan signal, the level of the scan signal rises, and the curvature of the convex parabola from the first level Tilting to a second level, at the end of the at least one of the scanning periods, the level of the scanning signal is lowered, and is tilted from the second level to the first level by the curvature of the concave parabola.

Optionally, the control circuit changes a portion of the change between the second level and the first level of the scan signal by inputting the control signal to the gate drive circuit.

[0008] Optionally, the number of the image signal lines is the same as the number of the scanning signal lines.

[0009] Optionally, the plurality of data signals are synchronously provided to the plurality of pixels through a plurality of the image signal lines, respectively.

[0010] Optionally, the gate driving circuit synchronously outputs a plurality of the scan signals to synchronously drive a plurality of the scan signal lines.

[0011] Optionally, the display device further includes a reverse electrode driving circuit, and the pixel capacitor and the auxiliary capacitor in the pixel are connected in parallel to a reverse potential of the reverse electrode driving circuit.

[0012] Optionally, the gate driving circuit includes a shift register portion composed of a plurality of flip-flop cascades, and the selection switch is respectively turned on or off according to outputs of the plurality of flip-flops. [0013] Optionally, the display device further includes a capacitor connected to an input of the gate driver, the level source is connected to the input of the gate driver through the first switch, and the resistor is transmitted through the second port The shunt is connected in parallel to the capacitor.

[0014] Optionally, the control circuit further includes an inverter, wherein the first off/off control is performed by a charge and discharge control signal, and the charge and discharge control signal is inverted by the inverter Performing the second control of the 幵/OFF control.

[0015] Optionally, the charge and discharge control signal is arranged to be synchronized with the chirp signal.

[0016] Optionally, when the charge and discharge control signal is at the second level 吋, the first switch is turned off, and the second switch is turned off due to the first level applied by the inverter. Broken, and the capacitor is charged

[0017] Optionally, when the charge and discharge control signal is at a first level 吋, the first 幵 is turned off, and the second 幵 is due to a first level applied by the inverter And turned off, and the charge stored in the capacitor is discharged through the resistor.

[0018] Embodiments of the present application provide a display device, including: a plurality of pixels arranged in a matrix; an image signal line for providing a data signal to the plurality of pixels; and a scan intersecting the image signal line a signal line; a gate driving circuit that outputs a scan signal to the scan signal line, and outputs a scan signal to drive the scan signal line; a control circuit that controls the gate drive circuit by a control signal, the control The signal has a waveform level accompanying a period of level change; and a capacitor connected to the input of the gate driver, wherein the level source is connected to the input of the gate driver through the first switch, and the resistance is transmitted through a second circuit is connected in parallel to the capacitor, wherein at least one of the scan periods of the scan signal begins, the level of the scan signal rises, and the first level is tilted from the curvature of the convex parabola to the first a second level, after the at least one of the scanning periods ends, the level of the scan signal decreases, and the concave level is thrown from the second level The curvature of the line is inclined to the first level; wherein the control circuit further includes an inverter, wherein the first off/off control is performed by a charge and discharge control signal, and the charge and discharge control signal passes through Performing the second off/off control after the inverter is inverted; when the charge and discharge control signal is at the second level, the first switch is off, and the second pass is passed a first level applied by the inverter is interrupted, and the capacitor is charged; when the charge and discharge control signal is at a second level 吋, the first 关闭 is off, and the second 幵 is off The sag is broken due to the first level applied by the inverter, and the capacitor is charged.

[0019] Optionally, the number of the image signal lines is the same as the number of the scanning signal lines.

[0020] Optionally, the plurality of data signals are synchronously provided to the plurality of pixels through a plurality of the image signal lines, respectively.

[0021] Optionally, the gate driving circuit synchronously outputs a plurality of the scan signals to synchronously drive a plurality of the scan signal lines.

[0022] Optionally, the display device further includes a reverse electrode driving circuit, and the pixel capacitor and the auxiliary capacitor in the pixel are connected in parallel to a reverse potential of the reverse electrode driving circuit.

[0023] Optionally, the charge and discharge control signal is arranged to be synchronized with the chirp signal.

[0024] Optionally, the charge and discharge control signal is arranged to be synchronized with each of the scan cycles.

[0025] Embodiments of the present application provide a display device, including: a plurality of pixels arranged in a matrix; an image signal line for providing a data signal to the plurality of pixels; and a scan intersecting the image signal line a signal line; a gate driving circuit that outputs a scan signal to the scan signal line, and outputs a scan signal to drive the scan signal line; a control circuit that controls the gate drive circuit by a control signal, the control The signal has a waveform level accompanying a period of level change; and a capacitor connected to the input of the gate driver, wherein the level source is connected to the input of the gate driver through the first switch, and the resistance is transmitted through a second circuit is connected in parallel to the capacitor, wherein at least one of the scan periods of the scan signal begins, the level of the scan signal rises, and the first level is tilted from the curvature of the convex parabola to the first a second level, after the at least one of the scanning periods ends, the level of the scan signal decreases, and from the second level The curvature of the parabolic line is tilted to the first level, wherein the control circuit causes the second level of the scan signal to be between the first level and the first level by inputting the control signal to the gate drive circuit A portion of the variation of the variation, wherein the gate drive circuit includes a shift register portion consisting of a plurality of flip-flop cascades, and the select switch is turned on or off according to the outputs of the plurality of flip-flops, respectively.

Advantageous effects of the invention

Beneficial effect

Generally, parasitic capacitance is inevitably formed between the gate and the drain of the thin film transistor. In the case where the scanning signal suddenly rises and falls under normal conditions, the thin film transistor immediately becomes an off state, because The potential of the pixel electrode (hereinafter referred to as a pixel potential) is lowered corresponding to the amount of rise and fall of the scan signal due to the parasitic capacitance (scan level minus the non-scan level), thereby causing a significant level of pixel potential Offset. This significant level shift of the pixel potential causes flickering of the displayed image, deterioration of the display, and the like. However, according to the above display device, the rise and fall of the scan signal are controlled, so that the scan signal can be controlled so as not to suddenly rise or fall. This ensures that the level shift of the pixel potential caused by the parasitic capacitance can be reduced.

Furthermore, a wire disposed on a transparent insulating substrate made of, for example, glass is not an ideal path, resulting in a signal delay path that experiences a signal delay to some extent. Therefore, the above structure ensures that display unevenness caused by signal delay is eliminated, and the level shift of the pixel potential caused by the parasitic capacitance becomes smaller and uniform. As a result, a high-performance display image can be obtained.

Brief description of the drawing

DRAWINGS

1 is an explanatory view showing a configuration of a conventional liquid crystal display device.

2 is an explanatory view showing a configuration of a conventional scanning signal line drive circuit.

3 is an equivalent circuit diagram of a display pixel in which a pixel capacitor and an auxiliary capacitor are connected in parallel to a reverse potential of a counter electrode driving circuit. [0030] FIG.

4 is a driving waveform diagram of a conventional liquid crystal display device.

[0032] FIG. 5 is a graph showing linear gate level versus drain current characteristics of a TFT.

6 is a transmission equivalent circuit diagram in the case where the signal transmission delay of one scanning signal line is focused.

7 is a waveform diagram showing output from a scanning signal line drive circuit assembly according to an embodiment of the present application.

8 is a waveform diagram showing a scanning signal line waveform in the vicinity of the input side end of the scanning signal line, a scanning signal line waveform in the vicinity of the other end of the scanning signal line, and a potential of each pixel.

9 is a configuration explanatory view showing a scanning signal line drive circuit according to another embodiment of the present application.

10 is a block diagram showing the configuration of a main part of a scanning signal line drive circuit according to still another embodiment of the present application.

11 is a configuration circuit diagram showing a main part of a scanning signal line drive circuit according to still another embodiment of the present application.

12 is a waveform diagram showing a main part of FIG. 11.

[0040] FIG. 13 is a waveform diagram showing output from a scanning signal line driving circuit assembly according to an embodiment of the present application.

14 is a diagram showing a waveform of a scanning signal line near the input side of a scanning signal line, according to an embodiment of the present application, A waveform of a scanning signal line near the other end of the signal line and a waveform of each pixel potential.

[0042] FIG. 15 is a waveform diagram showing output from a scanning signal line driving circuit component according to an embodiment of the present application.

16 is a waveform diagram showing a waveform of a scanning signal line near the input side of the scanning signal line, a waveform of a scanning signal line near the other end of the scanning signal line, and a potential of each pixel, according to an embodiment of the present application.

17 is a waveform diagram showing output from a scanning signal line driving circuit component according to an embodiment of the present application.

18 is a waveform diagram showing a waveform of a scanning signal line near the input side of the scanning signal line, a waveform of a scanning signal line near the other end of the scanning signal line, and potentials of the respective pixels, according to an embodiment of the present application.

19 is a waveform diagram showing output from a scanning signal line driving circuit assembly according to an embodiment of the present application.

20 is a waveform diagram showing a waveform of a scanning signal line near the input side of the scanning signal line, a waveform of a scanning signal line near the other end of the scanning signal line, and potentials of the respective pixels, according to an embodiment of the present application.

Embodiments of the invention

[0048] The technical solutions in the embodiments of the present application will be clearly and completely described in the following with reference to the accompanying drawings in the embodiments. It is apparent that the described embodiments are part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application, without departing from the inventive work, are within the scope of the present application.

[0049] The present application is made on the basis of: In a display device such as an LCD device, an input signal is not affected by a signal delayed transmission characteristic, and the input signal is input to a wiring disposed on a transparent insulating substrate And, by doing so, the same waveform as that of the input signal can be obtained at any position on the wire, and the influence caused by the signal change in the entire wire can be made constant.

[0050] The present application is also based on the following aspects: According to the on/off characteristics of a switching component such as a TFT connected to a wire, the parasitic capacitance can be reduced by making the input waveform and the waveform at a certain point of the wire substantially uniform. The resulting level shift.

Please refer to FIG. 1, which is an explanatory diagram of a structure of a liquid crystal display device according to an embodiment of the present application. The LCD device as described above includes the LCD panel 1 as a main component, and a driving circuit portion as shown in FIG. 1, and the LCD panel 1 is formed by sealing a liquid crystal composition between a pair of electrode substrates, and the deflecting plate It is formed by being disposed on the outer surface of the electrode substrate.

[0052] The TFT array substrate is a plurality of signal lines S1, S2, ... SN and a plurality of scanning lines G1, G2 in a matrix form ... GN is formed on the transparent insulating substrate 100, wherein the number of the signal lines S1, S2, ... SN is the same as the number of the scanning signal lines G1, G2, ... GN, in the embodiment, The transparent insulating substrate 100 may be, for example, glass. At each intersection of the signal line and the scanning line, a shut-off assembly 102 is provided which is composed of a TFT connected to the pixel electrode 103 and is provided with an alignment film covering all of the above components.

[0053] On the other hand, the reverse substrate as the other electrode substrate is laminated by the counter electrode 101 and the alignment film, and the reverse substrate is almost entirely made of a transparent insulating substrate, for example, a glass substrate. And as a TFT array substrate. The driving circuit portion is composed of a scanning signal line driving circuit 300, a signal line driving circuit 200, and a reverse electrode driving circuit COM, which are respectively connected to the scanning lines, signal lines and counter electrodes of the LCD panel. The control circuit 600 is a circuit for controlling the signal line drive circuit 200 and the scanning signal line drive circuit 300.

[0054] The scanning signal line driving circuit 300 can be regarded as a gate driver. The scanning signal line driving circuit 300 can synchronously output a plurality of scanning signals to synchronously drive the plurality of scanning signal lines 105. The scanning signal line driving circuit 30 0 can be For example, the shift register portion 3a composed of M flip-flop cascades and the selection switch 3b are composed, the number of shift register portions 3a is the same as the number of selection gates 3b, and the selection gate 3b is based on the received trigger. The output signal of the device is hiccup/closed, as shown in Figure 2. The input port VD 1 of each of the two input ports of each of the selection gates 3b is provided with a gate activation level Vgh sufficient to bring the switching component 102 (see FIG. 1) to the on state, and the other input port VD to provide There is a gate off level Vgl which is sufficient to bring the off-off assembly 102 to the off state. Therefore, in response to the chirp signal (GCK), the gate enable signal (GSP) is sequentially transferred through the flip-flops and sequentially output to the selection switch 3b. In response to this, each of the selection switches 3b selects the level Vgh for turning on the TFT, and outputs it to the scanning signal line 105 during one scanning period (TH), and then turns off the level for turning off the TFT. Vgl is output to the scanning signal line 105. In this operation, the image signals outputted from the signal line driving circuit 200 to the individual signal lines 104 can be written into the respective corresponding pixels. In this embodiment, the plurality of image signals are sequentially passed through the plurality of signal lines 1 respectively. 04 is provided to multiple pixels.

3 shows an equivalent circuit of a display pixel P (i, j) in which a pixel capacitor Clc and an auxiliary capacitor Cs are connected in parallel to a reverse potential VCOM of the counter electrode driving circuit COM. In the figure, Cgd represents the parasitic capacitance between the gate and the drain. Fig. 4 shows driving waveforms of a conventional LCD device. As shown in FIG. 4, Vg is a waveform of a signal for a single scanning signal line, Vs is a waveform of a signal for a single signal line, and Vd is a drain waveform. [0056] Here, a conventional driving method will be described below with reference to FIGS. 1, 3, and 4. Incidentally, it is known that the liquid crystal requires an AC drive to avoid occurrence of aging residual images and deterioration of display images, and the conventional driving method described below is explained by, for example, a frame inversion driver, which is an AC drive. When the scan level Vgh is applied to the gate g(i,j) of the single display pixel P(i,j) by the scan signal line drive circuit 30 0 in the first region (TF1) interval as shown in FIG. 4, the TFT reaches The startup state, and the image signal level Vsp from the signal line drive circuit 200 is applied to the pixel electrode through the source and drain electrodes of the TFT. The pixel electrode is maintained at the pixel potential Vdp as shown in FIG. 4 until the scan level Vgh is applied during the next region (TF2). Since the counter electrode has a potential set to a predetermined reverse potential VCOM by the counter electrode driving circuit COM, the liquid crystal composition held between the pixel electrode and the counter electrode is based on the pixel potential Vdp and the reverse potential VCOM The potential difference is responded to the image display.

[0057] Similarly, as shown in FIG. 4, the TFT gate g of the single display pixel P(i, j) applied from the scanning signal line drive circuit 300 during the second region (TF2) is shown in FIG. i, j) 吋, the TFT reaches the startup state, and the image signal level Vsn from the signal line drive circuit 200 is written to the pixel electrode. The pixel electrode is maintained at the pixel potential Vdn, and the liquid crystal composition responds based on the potential difference between the pixel potential Vdn and the reverse potential VCO M, thereby performing image display while achieving liquid crystal AC driving. Since the parasitic capacitance Cgd is inevitably formed between the gate and the drain of the TFT under the structure shown in FIG. 3, the level shift Vd caused by the parasitic capacitance Cgd occurs when the scanning level Vgh falls. The pixel potential Vd is as shown in FIG. The non-scanning level of the scanning signal (the level at which the TFT is in the OFF state 为) is Vgl, and the level shift Vd of the pixel potential Vd due to the parasitic capacitance Cgd which is inevitably formed in the TFT is expressed as:

Vd = Cgd (Vgh- Vgl) I (Clc + Cs + Cgd)

[0059] Since the level shift causes problems such as image flicker and display deterioration, it is disadvantageous for an LCD device in which higher definition and higher performance are required. Therefore, a measure has conventionally been proposed in which the counter potential VCOM of the opposite electrode is pre-biased so that the level shift Vd caused by the parasitic capacitance Cgd is decreased. However, with the above conventional techniques, it is difficult to arrange the scanning signal lines G ( 1 ) , G ( 2 ) , ... G (j) , ... G (M) in an ideal manner so that the scanning signal lines do not undergo signals. The transmission is delayed, thus causing the arranged scanning signal lines to experience signal delay to some extent.

[0060] Furthermore, the TFT is not completely turned on/off, but has a VI characteristic as shown in FIG. 5 (gate electric) Flat-drain current characteristics). As shown in Fig. 5, the level applied to the gate of the TFT is plotted as the abscissa axis, and the drain level is plotted as the vertical axis. Usually, the scan pulse is composed of two levels, one being a level Vgh sufficient to bring the TFT to an on state, and the other being a level Vgl sufficient to bring the TFT to an off state. However, as shown, there is also an intermediate conduction region (linear region) between the threshold levels VT and Vgh of the TFT.

6 is a transmission equivalent circuit diagram in the case where the signal transmission delay of one scanning signal line G (j) is focused. In Fig. 6, rgl, rg2, rg3, ... rgN mainly represent resistance components. Cgl, cg2, cg3... cgN represents various parasitic capacitances capacitively coupled to the structure of the scanning signal line. The parasitic capacitance includes a cross capacitance generated at the intersection of the scanning signal line and the signal line. Therefore, the scanning signal lines constitute a signal delay transmission path as shown. As described above, the level shift Vd at which the pixel potential Vd occurs due to the parasitic capacitance Cgd inside the panel is uneven in the entire display plane, and since the LCD device has a large screen and becomes higher in definition, So it becomes more difficult to ignore. Therefore, the conventional scheme of biasing the reverse level cannot absorb the difference in level shift across the entire display plane, so that optimum AC drive cannot be performed with respect to each pixel. Therefore, defects such as flickering and aging residual images due to the application of the alternating component are caused.

[0062] Hereinafter, an embodiment of the present application will be described with reference to Figs. 7 to 12 . Note that in Figure 7, CLK represents the chime signal. 7 and 8 show output waveforms VG(jl), VG(j), and VG(j+1) of the scanning signal line drive circuit according to the present embodiment, and the scanning signal line waveform Vg (1, j) is scanned. Near the input side of the signal line, the scanning signal line waveform Vg (N, j) is near the other end of the scanning signal line, and each pixel potential Vd (1, j) and Vd (N, j) are on the scanning signal line. Near the front end. In the output waveform VG (j) of the scanning signal line drive circuit, the rise and fall from the scan level Vgh to the non-scan level Vgl rise and fall by the slope (inclination) represented by the change rates SxF and SxE, which For the amount of change per unit, as shown in Figure 1.

By appropriately setting the change rates SxF and SxE, the rate of change SxF1 of the rising waveform near the input side end of the scanning signal line and the rate of change SxFN of the rising waveform near the other end of the scanning signal line become Substantially equal, the rate of change SxEl of the falling waveform near the input side end of the scanning signal line and the rate of change of the rising waveform near the other end of the scanning signal line SxEN scanning signal lines become substantially equal, and are not parasitic by the scanning signal line The effects of signal delay transmission characteristics, such as the scanning signal line waveforms Vg (1, j) and Vg (N, j) (see Figures 7 and 8). This causes the parasitic capacitance Cgd in the scanning signal line to be caused The level shift at which the pixel potential Vd occurs becomes substantially uniform over the entire display plane. As a result, by applying the conventional scheme of biasing the counter potential VCOM in order to previously reduce the level shift Vd of the pixel potential Vd due to the parasitic capacitance Cgd parasitic in the scanning signal line, etc., the display device can achieve sufficient reduction in flicker. And defects such as aging residual images do not occur.

[0064] In order to make the rate of change SxF1 and SxFN of the rising waveform substantially equal, and to make the rate of change S xEl and SxEN of the falling waveform substantially equal, without being affected by its position on the scanning line, it may be delayed based on the signal transmission Features to control the rise and fall. Control in this manner enables the slope of the scan signal to be substantially equal anywhere on the scan line, thereby causing the level shifts of the pixel electrodes to be substantially equal.

[0065] Based on the signal delay transmission characteristics instead of the above-described rising or falling control, the rising and falling slopes of the scanning signal can be controlled based on the gate level-drain current characteristics of the TFT. In the TFT, when a level within a threshold level is applied to a turn-on level 其 of its gate, a drain (conductive resistance) current of a TFT depending on a gate level linearly changes. In other words, the TFT is not in the ON state of the binary state, but reaches the intermediate ON state (wherein the drain current varies in analog form according to the gate level).

[0066] Alternatively, the slope of the rising and falling of the scan signal may be controlled based on the signal delay transmission of the TFT and the gate level-drain current characteristic. In this case, any rising slope of the scan signal can be made substantially equal to the rising slope anywhere on the scan signal line, and the slope of any drop of the scan signal is substantially equal to the drop anywhere on the scan signal line. Slope.

[0067] Optionally, the rate of change SxF of the inclined portion rising from the first level to the second level is different from the slope SxE of the inclined portion falling from the second level to the first level (as shown in FIG. 7 In this way, the waveform near the input of the scanning signal line and the vicinity of the terminal can be made to be substantially the same without being affected by the signal delay propagation characteristics of the scanning signal line parasitically, and the pixel potential Vd is lowered. The generation of the level shift causes a display device that does not display a defective image such as a residual image. As a result, the level shifts of the pixel potentials are made substantially equal to each other, and each level shift is lowered.

Further, the level VT shown in FIG. 8 is the threshold level of the TFT shown in FIG. 7, and since the TFT remains in the startup state while the scanning signal falls from the scanning level Vgh to the threshold level VT, The level shift caused by the parasitic capacitance Cgd hardly occurs in the above-described turn. On the other hand, since the scanning signal line offset (VT-Vgl) which causes the TFT to be turned off is affected by the parasitic capacitance Cgd, level shift occurs. [0069] Since VT-Vgl <Vgh-Vgl is satisfied in the present embodiment, not only the difference in level shift caused by the parasitic capacitance on the entire display plane can be eliminated, but also each of the parasitic capacitance Cgd can be reduced. Level offset.

[0070] Here, the level shift caused by the parasitic capacitance Cgd of the pixel near the end of the scanning signal line on the scanning signal line driving circuit side of the related art and the pixel potential Vd is Vd (1), In the case where the level shift of the pixel at the other end of the technique is Vd (N), the level of the pixel potential Vd near the end of the scanning signal line is further shifted by one of the scanning signal line driving circuits of the present embodiment. The side is Vdx (1), and the level shift of the pixel potential Vd at the other end of this embodiment occurs as Vdx (N) . In this case, since the rate of change SxF1 of the rising waveform, SxFN is substantially equal, and since the rate of change SxEl, SxEN of the rising waveform is substantially equal, and is not affected by the delayed transmission characteristic of the signal parasitic of the above scanning signal line, Therefore, the level shift occurring at the pixel potential Vd from the parasitic capacitance Cgd becomes substantially uniform over the entire display plane, and satisfies the following relationship (see FIGS. 2 and 15):

Vdx( 1 )=Vdx(N)<Vd(N)<Vd( 1 )

[0072] Therefore, by applying a conventional scheme of biasing the counter potential VCOM of the opposite electrode, the level shift generated from the parasitic capacitance is initially lowered, and it is possible to provide a lower bias level, less flicker and A display device that displays defects, for example, reduces aging residual images and has less power consumption.

[0073] Hereinafter, an embodiment of the present application will be described with reference to FIG. For the sake of convenience, have the same structure as in Figure 1.

(function) of the component. The same reference numerals are used in Fig. 9.

[0074] In the embodiment of the present application, as in the case of the conventional scanning signal line driving circuit shown in FIG. 2, as shown in FIG. 9, the scanning signal line driving circuit includes M flip-flops (F1, F2 ... , Fj ..., FM) The shift register portion 3a composed of cascades, and the selection gate 3b are respectively turned off according to the output of the flip-flop. The input terminal VD1 of the two input terminals of each selection switch 3b is supplied with a gate-on level Vgh sufficient to bring the TFT to an on state, and the other input terminal VD2 is supplied with a gate-on level. , the turn-off level Vgl, which is sufficient to bring the TFT to the OFF state. The common terminal of each of the switches 3b is connected to the scanning signal line 105.

[0075] Therefore, in response to the chopping clock signal (CLK), the gate enable signal (GSP) is sequentially transferred by the flip-flops and sequentially output to the selection switch 3b. In response to this, during one scan period (TH), each of the selection switches 3b selects the level Vgh for bringing the TFT to the on state, and outputs it to the scanning signal line 105, and then selects the level Vgl, TFT The off state is reached and output to the scanning signal line 105. [0076] Each slew rate control component SC disposed between the selection gate 3b and the input terminal VD2 is equivalently an output impedance control component that controls the impedance of each output of the gate driver, which is only rising and falling 吋Increase the output impedance. The gate-off level output to the scanning signal line (the rise and fall of the gate-off level is hereinafter referred to as "scanning signal line rising and scanning signal line rising and falling"), thereby making the output waveform of the gate driver dull. This results in a difference in the rising and falling speeds in the display panel, which stems from the fact that the waveform integrity as the transmission characteristic of the scanning signal line cancels each other. As a result, the occurrence of the level shift Vd due to the influence of the above-described parasitic capacitance Cgd can be suppressed, and the level shift between the entire display panels can be made equal.

On the other hand, the slew rate control component SC is not particularly limited, and may be any component that changes the output impedance to change the rising and falling speeds. This can be achieved by using known control techniques that adjust the impedance, for example, by controlling the gate level of the MOS transistor component.

[0078] Furthermore, the output impedance increases only when the scanning signal line rises and falls, so in the present embodiment, both the rising and falling waveforms become dull, but depending on the panel structure used, the output impedance can rise only on the scanning signal line. Or the scanning signal line is increased after the falling, but remains at an increased level unless the outputting of the gate-off level Vgl吋 after the falling of the scanning signal line occurs within another period of occurrence of another display defect such as crosstalk at a high impedance.

With the above embodiment, the case where the slew rate control unit SC for controlling the rising and falling speeds (slopes) of the scanning signals is added to the conventional structure of the scanning signal line driving circuit (gate driver) has been described. However, in this case, it is necessary to additionally provide the slew rate control component sc in the gate driver, and it is not possible to directly apply the conventional inexpensive gate driver. Therefore, this is not economical.

[0080] In an embodiment of the present application, a conventional inexpensive gate driver is used. This will be described below with reference to Figs. 10 and 11.

[0081] A conventional gate driver is as explained above with reference to FIG. 2. As shown in FIG. 2, the arrangement is as follows: a gate-on level Vgh and a gate-off level Vgl are provided, and in response to the chirp signal CLK, the gate driver sequentially outputs the scan-on level Vgh to the scanning signal line 105. That is, a row is selected in one scanning period (TH), and the level Vgl for causing the TFT to reach the off state of each scanning signal line 105 is output after the above-described scanning period. On the other hand, in the present embodiment, as shown in Fig. 10, the output thereof is used as the level Vgh of the scanning signal line drive circuit.

[0082] The signal level Vdd is applied to one terminal of the switch SW1. The signal level Vdd is the same as Vgh The level of the DC level is sufficient to bring the TFT to the on state. The other terminal of the switch SW1 is connected to one end of the resistor Rc nt and one terminal of the capacitor Cent. The other terminal of the resistor Rent is grounded via the switch S W2. The ON/OFF control of the OFF SW2 is performed in accordance with the signal Stc (see FIG. 11) supplied through the inverter INV. The signal Stc generated by the control unit not shown is synchronized with each scanning period, and is also used for the ON/OFF control of the S W1. The signal Stc is arranged to be synchronized with the chirp signal (CLK) as shown in FIG. For example, it can be generated by using a mono multivibrator (not shown).

Regarding the ON/OFF operation of the switches SW1 and SW2, when the signal Stc is at the second level 吋, the switch SW1 is turned off, the capacitor Cent is charged according to the signal Stc (charge control signal), and here the SW2 is passed through The phaser INV applies a first level and is broken. On the other hand, when the signal Stc is at the first level (discharge control signal) 吋, the switch SW1 is turned off, and here the switch SW2 is closed due to the application of the inverter INV to the second level. In short, in the arrangement shown in Fig. 1, as shown in Fig. 10, the switches SW1 and SW2 are the second level activation components.

The output signal VD1a generated by the above circuit is sent to the input terminal VD1 of the scanning signal line drive circuit 300 shown in FIG. 2. The signal Stc is a fixed signal for controlling the rise and fall of the gate (scanning signal rising and falling), as shown in Fig. 11, which is synchronized with each scanning period (TH).

According to the above configuration, when the signal Stc is at the second level 吋, the SW1 is turned off, the SW2 is turned off, and the output signal VDla is output as the level Vgh to the scanning input terminal VD1.

The signal line drive circuit 300. On the other hand, when the signal Stc is at the first level 吋, the switch SW1 is turned off, the same as the switch SW2 is turned off, and the charge stored in the capacitor Cent is discharged through the resistor Rent, whereby the level gradually decreases. As a result, the output signal VDla has a waveform as shown in FIG.

[0086] By transmitting the output signal VD1a (see FIG. 10) generated by the circuit shown in FIG. 12 to the input terminal VD1 of the scanning signal line driving circuit 300, a waveform of the falling of the scanning signal line can be generated, that is, as shown in FIG. The waveform shown is VG (j). The slope of the waveform is adjusted by changing the first level period of the signal Stc, and the slope Vslope is adjusted by changing the resistance of the resistor Rent and the capacitance of the capacitor Cent, so that the inter-turn constant of the circuit is adjusted. Therefore, it can be optimized for each display panel to be driven.

13 and FIG. 14 show output waveforms VG(j1), VG(j), and VG(j+1) of the scanning signal line drive circuit according to the present embodiment, and the scanning signal line waveform Vg (1, j) Near the input side end of the scanning signal line, the scanning signal line waveform Vg (N, j) is near the other end of the scanning signal line, and each pixel potential Vd (1) , j) and Vd (N, j) are near the front end of the scanning signal line. In the output waveform VG (j) of the scanning signal line drive circuit, the rise and fall from the scan level Vgh to the non-scan level Vgl rise and fall by the slope (inclination) represented by the change rates SxF and SxE, which For the amount of change per unit, as shown in Figure 13.

In the present embodiment, the rise and fall of the scan signal are controlled during the actuation as shown in FIG. 13, and the control of the rise and fall is realized by appropriately setting the change rates SxF and SxE.

[0089] Specifically, the waveform level generated by the gate driver is an inclined portion that includes an upward tilt in a non-vertical manner from a first level to a second level, and is maintained at a horizontal portion of the second level, And a sloped portion that is inclined downward by a non-perpendicular manner in which the second level is lowered to the first level. In order to achieve this, it is necessary to appropriately set the change rates SxF and SxE, the rate of change SxF1 of the rising waveform near the input side end of the scanning signal line, and the rate of change SxFN of the rising waveform near the other end of the scanning signal line. The lines become substantially equal, the rate of change SxEl of the falling waveform near the input side end of the scanning signal line, and the rate of change of the rising waveform near the other end of the scanning signal line SxEN scanning signal lines become substantially equal, and are not affected by the scanning signal The line parasitic signal delays the transmission characteristics, such as the scanning signal line waveforms Vg (1, j) and Vg (N, j) (see Figures 13 and 14). Similarly, this also makes it possible that the level shift of the pixel potential Vd due to the parasitic capacitance Cgd in the scanning signal line becomes substantially uniform over the entire display plane.

[0090] In order to make the rate of change SxF1 and SxFN of the rising waveform substantially equal, and to make the rate of change S xEl and SxEN of the falling waveform substantially equal, without being affected by its position on the scanning line, it may be delayed based on the signal transmission Features to control the rise and fall. Control in this manner enables the slope of the scan signal to be substantially equal anywhere on the scan line, thereby causing the level shifts of the pixel electrodes to be substantially equal.

Based on the signal delay transfer characteristic instead of the above-described rise or fall control, the rising and falling slopes of the scan signal can be controlled based on the gate level-drain current characteristics of the TFT. In the TFT, when a level within a threshold level is applied to a turn-on level 其 of its gate, a drain (conductive resistance) current of a TFT depending on a gate level linearly changes. In other words, the TFT is not in the startup state in the binary state, but is in the intermediate startup state (wherein the drain current changes in analog form according to the gate level).

In the present embodiment, the rising and falling slopes of the scan signal can be controlled such that the slope is affected when the TFT is in the above-described linearly varying state (intermediate on state). Scanning due to such control The rise and fall of the signal become tilted, and the TFT is also linearly shifted from the on state to the off state according to the level-current characteristic, so it is surely possible to make each of the pixel potentials generated from the parasitic capacitance The flat offset does decrease.

[0093] Further, the waveform level generated by the scan signal and the gate level-drain current characteristic of the TFT may be controlled to include a non-vertical rise from the first level to the second level. The inclined portion that is inclined upward is maintained at a horizontal portion of the second level, and a tilted portion that is inclined downward by a second level down to a first level in a non-vertical manner. In this case, the waveform near the input of the scanning signal line and the vicinity of the terminal can be made substantially the same as the signal delay propagation characteristics of the scanning signal line parasitically, and the pixel potential Vd can be lowered. The generation of a level shift. In this way, the waveform near the input of the scanning signal line and the vicinity of the terminal can be made to be substantially the same by the signal delay propagation characteristics of the scanning signal line parasitically, and the pixel potential V bit shift can be reduced. The generation of bits enables display devices that do not display defects such as residual images. As a result, the level shifts of the pixel potentials are made substantially equal to each other, and each level shift is lowered.

Further, the level VT shown in FIG. 14 is the threshold level of the TFT shown in FIG. 13, and since the TFT remains in the startup state while the scanning signal falls from the scanning level Vgh to the threshold level VT, The level shift caused by the parasitic capacitance Cgd hardly occurs in the above-described turn. On the other hand, since the scanning signal line offset (VT-Vgl) which causes the TFT to be turned off is affected by the parasitic capacitance Cgd, level shift occurs.

[0095] Since VT-Vgl <Vgh-Vgl is satisfied in the present embodiment, not only the difference in level shift caused by the parasitic capacitance on the entire display plane can be eliminated, but also each of the parasitic capacitance Cgd can be reduced. Level offset.

[0096] Here, the level shift caused by the parasitic capacitance Cgd of the pixel near the end of the scanning signal line on the scanning signal line drive circuit side of the related art and the pixel potential Vd is Vd (1), In the case where the level shift of the pixel at the other end of the technique is Vd (N), the level of the pixel potential Vd near the end of the scanning signal line is further shifted by one of the scanning signal line driving circuits of the present embodiment. The side is Vdx (1), and the level shift of the pixel potential Vd at the other end of this embodiment occurs as Vdx (N). In this case, since the rate of change SxF1 of the rising waveform, SxFN is substantially equal, and since the rate of change SxEl, SxEN of the rising waveform is substantially equal, and is not affected by the delayed transmission characteristic of the signal parasitic of the above scanning signal line, Therefore, the level shift of the pixel potential Vd from the parasitic capacitance Cgd is on the entire display plane. It becomes almost uniform and satisfies the following relationship (see Figures 2 and 15):

Vdx( 1 )=Vdx(N)<Vd(N)<Vd( 1 )

[0098] Therefore, by applying a conventional scheme of biasing the counter potential VCOM of the opposite electrode, the level shift generated from the parasitic capacitance is initially lowered, and a lower bias level, less flicker and A display device that displays defects, for example, reduces aging residual images and has less power consumption.

15 and FIG. 16 show output waveforms VG(j1), VG(j), and VG(j+1) of the scanning signal line drive circuit according to the present embodiment, and a scanning signal line waveform Vg (1, j) Near the input side end of the scanning signal line, the scanning signal line waveform Vg (N, j) is near the other end of the scanning signal line, and each pixel potential Vd (1 , j) and Vd (N, j) are scanned. Near the front end of the signal line. In the output waveform VG (j) of the scanning signal line drive circuit, the rise and fall from the scan level Vgh to the non-scan level Vgl rise and fall by the slope (inclination) represented by the change rates SxF and SxE, which For the amount of change per unit, as shown in Figure 15.

In the present embodiment, the rise and fall of the scan signal are controlled during the actuation as shown in FIG. 15, and the control of the rise and fall is realized by appropriately setting the change rates SxF and SxE.

[0101] Specifically, the waveform level generated by the gate driver is raised from the first level by the curvature of the convex parabola to the second level, and further includes the non-lowering from the second level to the first level. Inclined portion that slopes vertically downwards. In order to achieve this, it is necessary to appropriately set the change rates SxF and SxE, the rate of change SxF1 of the rising waveform near the input side end of the scanning signal line, and the rate of change SxFN of the rising waveform near the other end of the scanning signal line. The lines become substantially equal, the rate of change SxEl of the falling waveform near the input side end of the scanning signal line, and the rate of change of the rising waveform near the other end of the scanning signal line SxE N the scanning signal line become substantially equal, and are not scanned The signal line parasitic signal delays the transmission characteristics, such as the scanning signal line waveforms Vg (1, j) and Vg (N, j) (see Figures 15 and 16). Similarly, this also makes it possible that the level shift of the pixel potential Vd due to the parasitic capacitance Cgd in the scanning signal line becomes substantially uniform over the entire display plane.

[0102] In order to make the rate of change SxF1 and SxFN of the rising waveform substantially equal, and to make the rate of change S xEl and SxEN of the falling waveform substantially equal, without being affected by its position on the scanning line, it may be delayed based on the signal transmission Features to control the rise and fall. Control in this manner enables the slope of the scan signal to be substantially equal anywhere on the scan line, thereby causing the level shift of the pixel electrode to be substantially Equal.

[0103] Based on the signal delay transmission characteristic instead of the above-described rising or falling control, the rising and falling slopes of the scanning signal can be controlled based on the gate level-drain current characteristics of the TFT. In the TFT, when a level within a threshold level is applied to a turn-on level 其 of its gate, a drain (conductive resistance) current of a TFT depending on a gate level linearly changes. In other words, the TFT is not in the startup state in the binary state, but is in the intermediate startup state (wherein the drain current changes in analog form according to the gate level).

In the present embodiment, the rising and falling slopes of the scanning signal can be controlled such that the slope is affected when the TFT is in the above-described linear change state (intermediate on state). Since such control makes the rise and fall of the scan signal become tilted, the same TFT is also linearly shifted from the on state to the off state according to the level-current characteristic, so that it can be surely generated from the parasitic capacitance. Each level shift of the pixel potential does decrease.

[0105] More optionally, in one scan period, the rate of change SxF of the rising waveform is controlled to vary from day to day, for example, from large to small, and then the rate of change SxE of the falling waveform is only present in the second signal of the scan signal. Flattening down to the first level of the non-vertical mode obliquely inclined portion, the waveform located near the input of the scanning signal line and near the terminal can be prevented from being parasiticly transmitted by the scanning signal line. The influence is substantially the same, and the generation of the level shift of the pixel potential Vd is reduced, and a display device having no display defect such as a residual image is realized. As a result, the level shifts of the pixel potentials are made substantially equal to each other, and each level shift is lowered.

Further, the level VT shown in FIG. 16 is the threshold level of the TFT shown in FIG. 15, and since the TFT remains in the startup state while the scanning signal falls from the scanning level Vgh to the threshold level VT, The level shift caused by the parasitic capacitance Cgd hardly occurs in the above-described turn. On the other hand, since the scanning signal line offset (VT-Vgl) which causes the TFT to be turned off is affected by the parasitic capacitance Cgd, level shift occurs.

[0107] Since VT-Vgl <Vgh-Vgl is satisfied in the present embodiment, not only the difference in level shift caused by the parasitic capacitance on the entire display plane can be eliminated, but also each of the parasitic capacitance Cgd can be reduced. Level offset.

Here, the level shift caused by the parasitic capacitance Cgd of the pixel near the end of the scanning signal line on the scanning signal line drive circuit side of the related art and the pixel potential Vd is Vd (1), In the case where the level shift of the pixel at the other end of the technique is Vd (N), the image near the end of the scanning signal line is further caused. The level shift of the prime potential Vd is Vdx (1) on one side of the scanning signal line drive circuit of the present embodiment, and the level shift of the pixel potential Vd at the other end of the embodiment is Vdx (N) . In this case, since the rate of change SxF1 of the rising waveform, SxFN is substantially equal, and since the rate of change SxEl, SxEN of the rising waveform is substantially equal, and is not affected by the delayed transmission characteristic of the signal parasitic of the above scanning signal line, Therefore, the level shift occurring at the pixel potential Vd from the parasitic capacitance Cgd becomes substantially uniform over the entire display plane, and satisfies the following relationship (see FIGS. 15 and 16):

Vdx( 1 )=Vdx(N)<Vd(N)<Vd( 1 )

[0110] Therefore, by applying a conventional scheme of biasing the counter potential VCOM of the opposite electrode, the level shift generated from the parasitic capacitance is initially lowered, and a lower bias level, less flicker and A display device that displays defects, for example, reduces aging residual images, and has less power consumption.

17 and 18 show output waveforms VG(j1), VG(j), and VG(j+1) of the scanning signal line drive circuit according to the present embodiment, and the scanning signal line waveform Vg (1, j) Near the input side end of the scanning signal line, the scanning signal line waveform Vg (N, j) is near the other end of the scanning signal line, and each pixel potential Vd (1 , j) and Vd (N, j) are scanned. Near the front end of the signal line. In the output waveform VG (j) of the scanning signal line drive circuit, the rise and fall from the scan level Vgh to the non-scan level Vgl rise and fall by the slope (inclination) represented by the change rates SxF and SxE, which For the amount of change per unit, as shown in Figure 17.

In the present embodiment, the rise and fall of the scan signal are controlled during the actuation as shown in FIG. 17, and the control of the rise and fall is realized by appropriately setting the change rates SxF and SxE. Specifically, the waveform level generated by the gate driver is an inclined portion that includes an upward tilt from a non-perpendicular manner in which the first level is raised to a second level, and then the second level is decreased by the curvature of the concave parabola to the first One level (as shown in Figure 17). In order to achieve this, it is necessary to appropriately set the change rates SxF and SxE, the rate of change SxF1 of the rising waveform near the input side end of the scanning signal line, and the rate of change SxFN of the rising waveform near the other end of the scanning signal line. The lines become substantially equal, the rate of change SxEl of the falling waveform near the input side end of the scanning signal line, and the rate of change of the rising waveform near the other end of the scanning signal line SxEN scanning signal lines become substantially equal, and are not affected by the scanning signal The line parasitic signal delays the transmission characteristics, such as the scanning signal line waveforms Vg (1, j) and Vg (N, j) (see Figures 17 and 18). Similarly, this also makes it possible to shift the level of the pixel potential Vd due to the parasitic capacitance Cgd in the scanning signal line over the entire display. It becomes almost uniform on the plane.

[0113] In order to make the rate of change SxF1 and SxFN of the rising waveform substantially equal, and to make the rate of change S xEl and SxEN of the falling waveform substantially equal, without being affected by its position on the scanning line, it may be delayed based on the signal transmission Features to control the rise and fall. Control in this manner enables the slope of the scan signal to be substantially equal anywhere on the scan line, thereby causing the level shifts of the pixel electrodes to be substantially equal.

[0114] Based on the signal delay transmission characteristics instead of the above-described rising or falling control, the rising and falling slopes of the scanning signal can be controlled based on the gate level-drain current characteristics of the TFT. In the TFT, when a level within a threshold level is applied to a turn-on level 其 of its gate, a drain (conductive resistance) current of a TFT depending on a gate level linearly changes. In other words, the TFT is not in the startup state in the binary state, but is in the intermediate startup state (wherein the drain current changes in analog form according to the gate level).

In the present embodiment, the rising and falling slopes of the scanning signal can be controlled such that the slope is affected when the TFT is in the above-described linear change state (intermediate on state). Since such control makes the rise and fall of the scan signal become tilted, the same TFT is also linearly shifted from the on state to the off state according to the level-current characteristic, so that it can be surely generated from the parasitic capacitance. Each level shift of the pixel potential does decrease. More optionally, in one scan period, the rate of change SxF of the control rising waveform appears only in the inclined portion in which the scanning signal is tilted upward from the first level to the second level in a non-vertical manner, and then the falling waveform is controlled. The rate of change SxE varies from day to day, for example, from small to large, and therefore, at the end of one scan period, a scan signal that drops from the second level to the first level with the curvature of the concave parabola can be generated. In this way, the waveform located near the input of the scanning signal line and in the vicinity of the terminal can be affected by the signal delay propagation characteristics of the scanning signal line parasitically, and becomes substantially the same, and the level shift of the pixel potential Vd is lowered. The generation of a display device that does not display a defective image such as a residual image. As a result, the level shifts of the pixel potentials are substantially equal to each other, and each level shift is lowered.

Further, the level VT shown in FIG. 18 is the threshold level of the TFT shown in FIG. 17, and since the TFT remains in the startup state while the scanning signal falls from the scanning level Vgh to the threshold level VT, The level shift caused by the parasitic capacitance Cgd hardly occurs in the above-described turn. On the other hand, since the scanning signal line offset (VT-Vgl) which causes the TFT to be turned off is affected by the parasitic capacitance Cgd, level shift occurs. Since VT-Vgl <Vgh-Vgl is satisfied in this embodiment, not only the parasitic electricity on the entire display plane can be eliminated. The difference in level shift caused by the capacitance, and each level shift caused by the parasitic capacitance Cgd can be reduced. In this case, since the rate of change SxF1 of the rising waveform, SxFN is substantially equal, and since the rate of change SxEl, SxEN of the rising waveform is substantially equal, and is not affected by the delayed transmission characteristic of the signal parasitic of the above scanning signal line, Therefore, the level shift occurring at the pixel potential Vd from the parasitic capacitance Cgd becomes substantially uniform over the entire display plane, and satisfies the following relationship (see FIGS. 2 and 15):

Vdx( 1 )=Vdx(N)<Vd(N)<Vd( 1 )

[0118] Therefore, by applying a conventional scheme of biasing the counter potential VCOM of the opposite electrode, the level shift generated from the parasitic capacitance is initially lowered, and a lower bias level, less flicker and A display device that displays defects, for example, reduces aging residual images, and has less power consumption.

19 and 20 show output waveforms VG(j1), VG(j), and VG(j+1) of the scanning signal line drive circuit according to the present embodiment, and the scanning signal line waveform Vg (1, j) Near the input side end of the scanning signal line, the scanning signal line waveform Vg (N, j) is near the other end of the scanning signal line, and each pixel potential Vd (1 , j) and Vd (N, j) are scanned. Near the front end of the signal line. In the output waveform VG (j) of the scanning signal line drive circuit, the rise and fall from the scan level Vgh to the non-scan level Vgl rise and fall by the slope (inclination) represented by the change rates SxF and SxE, which For the amount of change per unit, as shown in Figure 19.

In the present embodiment, the rise and fall of the scan signal are controlled during the actuation as shown in FIG. 19, and the control of the rise and fall is realized by appropriately setting the change rates SxF and SxE. Specifically, the waveform level generated by the gate driver is raised from the first level by the curvature of the convex parabola to the second level, and then decreased by the second level to the first level by the curvature of the concave parabola. In order to achieve this, it is necessary to appropriately set the rate of change SxF and SxE, the rate of change SxF1 of the rising waveform near the input side end of the scanning signal line, and the rate of change SxFN of the rising waveform near the other end of the scanning signal line. The lines become substantially equal, the rate of change SxEl of the falling waveform near the input side end of the scanning signal line, and the rate of change of the rising waveform near the other end of the scanning signal line SxEN scanning signal lines become substantially equal, and are not affected by the scanning signal The line parasitic signal delays the transmission characteristics, such as the scanning signal line waveforms Vg (1, j) and Vg (N, j) (see Figures 19 and 20). Similarly, this also makes it possible to make the level shift due to the pixel potential Vd from the parasitic capacitance Cgd in the scanning signal line become substantially uniform over the entire display plane.

[0121] In order to make the rate of change SxF1 and SxFN of the rising waveform substantially equal, and the rate of change S of the falling waveform xEl and SxEN are substantially equal, and are not affected by their position on the scan line, and the rise and fall control can be performed based on the signal delay transmission characteristics. Control in this manner enables the slope of the scan signal to be substantially equal anywhere on the scan line such that the level shifts of the pixel electrodes are substantially equal. The rise and fall slopes of the scan signal can be controlled based on the gate level-drain current characteristics of the TFT based on the signal delay transfer characteristic instead of the above-described rise or fall control. In the TFT, when a level within a threshold level range is applied to a turn-on level 其 of its gate, a drain (on-resistance) current of a TFT depending on a gate level linearly changes. In other words, the TFT is not in the startup state of the binary state, but reaches the intermediate startup state (wherein the drain current varies in analog form according to the gate level).

In the present embodiment, the rising and falling slopes of the scanning signal can be controlled such that the slope is affected when the TFT is in the above-described linear change state (intermediate on state). Since such control makes the rise and fall of the scan signal become tilted, the same TFT is also linearly shifted from the on state to the off state according to the level-current characteristic, so that it can be surely generated from the parasitic capacitance. Each level shift of the pixel potential does decrease. More optionally, in a scan period, the rate of change SxF of the rising waveform is controlled to vary from day to day, for example, from large to small, so that at the front end of one scan period, a convex parabola can be generated by the first level. The curvature rises to the scanning signal of the second level, and then the rate of change S xE of the falling waveform is controlled to vary from day to day, for example, from small to large, and therefore, at the end of one scanning period, the second level can be generated The curvature of the concave parabola drops to the scan signal of the first level. In this way, the generation of the level shift of the pixel potential Vd can be further reduced, and the waveform located near the input of the scanning signal line and in the vicinity of the terminal can be prevented from being affected by the signal delay propagation characteristics of the scanning signal line parasitically. On the other hand, the generation of the level shift of the pixel potential Vd is reduced, and a display device having no display defect such as a residual image is realized. As a result, the level shifts of the pixel potentials are made substantially equal to each other, and each level shift is lowered.

Further, the level VT shown in FIG. 18 is the threshold level of the TFT shown in FIG. 1, and since the TFT remains in the startup state while the scanning signal falls from the scanning level Vgh to the threshold level VT, The level shift caused by the parasitic capacitance Cgd hardly occurs in the above-described turn. On the other hand, since the scanning signal line offset (VT-Vgl) which causes the TFT to be turned off is affected by the parasitic capacitance Cgd, level shift occurs. Since VT-Vgl <Vgh-Vgl is satisfied in the present embodiment, not only the difference in level shift caused by the parasitic capacitance on the entire display plane can be eliminated, but also each level shift caused by the parasitic capacitance Cgd can be reduced. shift. [0124] In this case, since the rate of change SxF1 of the rising waveform, SxFN is substantially equal, and since the rate of change SxEl, SxEN of the rising waveform is substantially equal, the signal is not delayed by the above-mentioned scanning signal line. The influence of the level shift of the pixel potential Vd from the parasitic capacitance Cgd I becomes substantially uniform over the entire display plane and satisfies the following relationship (see Figs. 2 and 15):

Vdx( 1 )=Vdx(N)<Vd(N)<Vd( 1 )

[0126] Therefore, by applying a conventional scheme of biasing the counter potential VCOM of the opposite electrode, the level shift generated from the parasitic capacitance is initially lowered, and it is possible to provide a lower bias level, less flicker and A display device that displays defects, for example, reduces aging residual images, and has less power consumption.

[0127] In the display device of the present application, the scanning signal line driving circuit controls the falling of the scanning signal line such that the pixel potential is substantially level-shifted on the display surface, and the level shift is parasitic on the scanning signal line. Caused by the capacitor. The falling waveform of the scanning signal changes at a rate of change Sx of the amount of change per unit turn, and it is desirable to set the rate of change Sx to a rate of change Sxl near the input side end of the scanning signal line, like the scanning signal line waveform Vg (1) , j) Like Vg (N, j), the rate of change SxN near the other end is substantially equal, independent of the signal delay transmission characteristics of the scanning signal line).

[0128] In the above embodiments, the display device configured as described above is applicable to a liquid crystal display device, an OLED display device, a QLED display device, a curved display device, or other display device, which is not limited herein.

[0129] It should be noted that, in the foregoing embodiments, the descriptions of the various embodiments are different, and the parts that are not described in detail in an embodiment may refer to related descriptions of other embodiments.

The above description is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any person skilled in the art can easily think of various kinds within the technical scope disclosed in the present application. Equivalent modifications or substitutions are intended to be included within the scope of the present application. Therefore, the scope of protection of this application shall be subject to the scope of protection of the claims.

Claims

Claim

[Claim 1] A display device, comprising:

a plurality of pixels arranged in a matrix;

An image signal line for providing a data signal to the plurality of pixels; a scanning signal line intersecting the image signal line;

a gate driving circuit that outputs a scan signal to the scan signal line and outputs a scan signal to drive the scan signal line;

a control circuit that controls the gate drive circuit by a control signal having a waveform level of a period accompanying a level change;

Wherein at least one of the scan periods of the scan signal begins, the level of the scan signal rises and is tilted from a first level to a second level at a curvature of a convex parabola, at least one of At the end of the scanning period, the level of the scanning signal drops and is tilted from the second level to the first level with the curvature of the concave parabola.

[Claim 2] The display device according to claim 1, wherein the control circuit causes the second level and the scan signal to be generated by inputting the control signal to the gate drive circuit A portion of the change between levels changes.

[Claim 3] The display device according to claim 1, wherein the number of the image signal lines is the same as the number of the scanning signal lines.

[Claim 4] The display device according to claim 1, wherein the plurality of data signals are synchronously supplied to the plurality of pixels through a plurality of the image signal lines, respectively.

[Claim 5] The display device according to claim 1, wherein the gate driving circuit synchronously outputs a plurality of the scanning signals to synchronously drive a plurality of the scanning signal lines.

[Claim 6] The display device according to claim 1, further comprising a reverse electrode driving circuit, wherein a pixel capacitor and an auxiliary capacitor in the pixel are connected in parallel to a reverse direction of the opposite electrode driving circuit Potential.

[Claim 7] The display device according to claim 1, wherein the gate driving circuit includes a shift register portion composed of a plurality of flip-flop cascades, and selecting a gate according to the plurality of flip-flops The output is turned on or off separately. A display device according to claim 1, further comprising a capacitor connected to an input of said gate driver, said level source being connected to an input of said gate driver through said first gate, and said resistor is transmitted A second switch is connected in parallel to the capacitor.

The display device according to claim 8, wherein the control circuit further includes an inverter, wherein the first off/off control is performed by a charge and discharge control signal, and the charge and discharge control signal passes through Performing the second on/off control after the inverter is inverted. The display device according to claim 9, wherein the charge and discharge control signal is arranged to be synchronized with the cuckoo clock signal.

The display device according to claim 9, wherein when said charge and discharge control signal is at a second level 吋, said first 关闭 is turned off, and said second 幵 is applied by said inverter The first level is broken and the capacitor is charged.

The display device according to claim 9, wherein when said charge and discharge control signal is at a first level 吋, said first 幵 is turned off, and said second 幵 is applied by an inverter The first level is turned off, and the charge stored in the capacitor is discharged through the resistor.

A display device, comprising:

a plurality of pixels arranged in a matrix;

An image signal line for providing a data signal to the plurality of pixels;

a scanning signal line intersecting the image signal line;

a capacitor connected to the input of the gate driver, wherein the level source is connected to the input of the gate driver through the first switch, and the resistor is connected in parallel to the capacitor through the second switch

Wherein at least one scan period of the scan signal begins, the scan signal The level rises and is tilted from the first level to the second level with the curvature of the convex parabola, and after the at least one of the scanning periods ends, the level of the scan signal decreases, and from the second Level is tilted to the first level with a curvature of the concave parabola;

Wherein the control circuit further includes an inverter, wherein the first off/off control is performed by a charge and discharge control signal, and the charge and discharge control signal is inverted by the inverter to perform the second turn Off/off control; when the charge and discharge control signal is at a second level 吋, the first 关闭 is off, and the second 由于 is due to a first level applied by the inverter Breaking, and charging the capacitor; when the charge and discharge control signal is at a second level 吋, the first 关闭 is off, and the second 由于 is due to a first level applied by the inverter Broken, and the capacitor is charged.

[Claim 14] The display device according to claim 13, wherein the number of the image signal lines is the same as the number of the scanning signal lines.

[Claim 15] The display device according to claim 13, wherein the plurality of data signals are synchronously supplied to the plurality of pixels through a plurality of the image signal lines, respectively.

The display device according to claim 13, wherein the gate driving circuit synchronously outputs a plurality of the scanning signals to synchronously drive the plurality of scanning signal lines.

[Claim 17] The display device according to claim 13, further comprising a counter electrode driving circuit, wherein the pixel capacitor and the auxiliary capacitor in the pixel are connected in parallel to the reverse of the counter electrode driving circuit Potential.

[Claim 18] The display device according to claim 13, wherein the charge and discharge control signal is arranged to be synchronized with the cuckoo clock signal.

[Claim 19] The display device according to claim 13, wherein the charge and discharge control signal is arranged to be synchronized with each of the scanning periods.

[Claim 20] A display device, comprising:

a plurality of pixels arranged in a matrix;

a gate driving circuit that outputs a scan signal to the scan signal line and outputs a scan signal Number to drive the scanning signal line;

Wherein at least one of the scan periods of the scan signal begins, the level of the scan signal rises and is tilted from a first level to a second level at a curvature of a convex parabola, at least one of At the end of the scanning period, the level of the scanning signal decreases, and the curvature from the concave level of the concave parabola is tilted from the second level to the first level,

Wherein the control circuit changes a portion of a change between a second level of the scan signal and a first level by inputting the control signal to the gate drive circuit, wherein the gate drive circuit A shift register portion consisting of a plurality of flip-flop cascades is included, and the selection is turned on or off according to the outputs of the plurality of flip-flops, respectively.