CN103913910A - Pixel unit structure, array substrate structure and liquid crystal display device - Google Patents

Abstract

The invention discloses a pixel unit structure, an array structure and a liquid crystal display device, which are used to solve the problem of poor display effect of the liquid crystal display device in the prior art, wherein the pixel unit comprises: a first electrode, a second electrode and a shielding An electrode; the first electrode is a planar structure; a first insulating layer is formed on the first electrode; the second electrode is formed on the first insulating layer, and the second electrode includes a plurality of strips The plurality of strip-shaped electrodes are arranged at intervals; a shielding electrode is arranged at the end of the plurality of strip-shaped electrodes of the second electrode. With the above technical solution, when there is an electrical signal in the pixel unit, due to the existence of the shielding electrode, the electric field in the Ey direction generated by the end of the strip electrode of the second electrode will be shielded, thereby effectively avoiding the domain line phenomenon and ensuring the pixel unit The display molecules corresponding to all the display areas can be rotated according to the preset method, which improves the display effect of the screen.

Description

A pixel unit structure, an array substrate structure and a liquid crystal display device

technical field

The invention relates to the field of display device manufacturing, in particular to a pixel unit structure, an array structure and a liquid crystal display device.

Background technique

With the rapid development of science and technology, the performance of display devices of electronic products has been greatly improved, and various large-size, high-resolution display devices have been widely used.

At present, display devices usually adopt TN (Twisted Nematic, twisted nematic) display mode, ADS (ADvanced Super Dimension Switch, advanced super dimension field switching technology) display mode and FFS (Fringe Filed Switching; fringe field switching technology) display mode.

The FFS display mode is favored by the market due to its advantages such as large viewing angle and high light transmittance. However, in the FFS display mode in the prior art, display abnormalities may occur on the side of the pixel unit away from the TFT (Thin Film Transistor, Thin Film Field Effect Transistor). FIG. 1 is a luminescence simulation diagram of a pixel unit in the FFS display mode in the prior art. As shown in FIG. 1 , one end of a strip-shaped electrode is connected to a TFT 12 , and the other end extends in the opposite direction. On the side of the pixel unit away from the TFT 12 there is a black area 11 , and the black area 11 is an abnormal display area, which reduces the display effect.

Contents of the invention

After research, the inventors found that in the FFS display mode, the abnormal display of the pixel unit on the side away from the TFT is caused by the following reasons.

Referring to FIG. 2A and FIG. 2B, FIG. 2A is a top structural view of a pixel unit in the FFS driving mode in the prior art. In the pixel unit in the FFS driving mode, it includes a common electrode 10 and a pixel electrode 20, wherein the pixel electrode 20 includes A plurality of strip electrodes 200 . FIG. 2B is a schematic cross-sectional view along AA' in FIG. 2A . As shown in the figure, the pixel unit in the FFS driving mode includes a common electrode 10, a pixel electrode 20, and a first insulating layer 30 interposed between the common electrode 10 and the pixel electrode 20, wherein the pixel electrode 20 includes multiple Strip electrodes 200 .

Referring to FIG. 2A, when an electrical signal is input to a pixel unit in the FFS drive mode, an electric field Ex in the x direction will be formed between each strip electrode 200 of the pixel electrode 20 and the common electrode 10, and an electric field Ex in the x direction will be formed between the strip electrodes 200 of the pixel electrode 20. The end of the electrode 200 cannot be canceled by other electric fields except the electric field in the x direction, so there are electric fields E in various directions at the end of the strip electrode 200 of the pixel electrode 20 . Referring to Figure 2A, after the force analysis of the electric field E, there is an electric field component Ey in the y direction of the electric field E, because in the pixel unit of the FFS driving mode, the Ex driven display molecules mainly formed by the pixel electrode follow the preset method Rotate to present a corresponding picture, and the electric field Ey will cause the display molecules at the end of the strip electrode 200 of the pixel electrode 20 to fail to rotate in a preset manner, resulting in a relatively serious defect in the picture presented by each pixel unit of the display device. The black area 11, and when the voltage of the display device increases, the black area 11 on the screen presented by the display device will increase, which will greatly affect the display effect of the screen.

It can be seen that, in the prior art, there are black areas in the picture presented by the display device, which leads to the problem that the display effect of the picture of the display device is poor.

Embodiments of the present invention provide an array substrate and a liquid crystal display device, which are used to solve the problem of poor display effect of display devices in the prior art.

The specific technical scheme that the embodiment of the present invention provides is as follows:

A pixel unit structure, the pixel unit comprising: a first electrode, a second electrode and a shielding electrode;

The first electrode is a planar structure;

A first insulating layer is formed on the first electrode;

The second electrode is formed on the first insulating layer, and the second electrode includes a plurality of strip electrodes, and the plurality of strip electrodes are arranged at intervals;

A shielding electrode is provided at an end of the plurality of strip electrodes of the second electrode.

An array structure of pixel units, comprising a plurality of pixel units defined by intersections of scanning lines and data lines, the pixel units being the aforementioned pixel units.

A liquid crystal display device includes the above-mentioned array structure, a color filter substrate, and a liquid crystal layer arranged between the array substrate and the color filter substrate.

In the embodiment of the present invention, the pixel unit includes: a first electrode, a second electrode and a shielding electrode; the first electrode has a planar structure; a first insulating layer is formed on the first electrode; Two electrodes are formed on the first insulating layer, and the second electrode includes a plurality of strip electrodes, and the plurality of strip electrodes are arranged at intervals; With shielding electrode. With the above technical scheme, when there is an electrical signal in the pixel unit, due to the existence of the shielding electrode, the electric field in the Ey direction generated by the end of the strip electrode of the second electrode will be shielded, thereby effectively avoiding the appearance of the black abnormal display area and ensuring The display molecules corresponding to all the display areas of the pixel unit can be rotated in a preset manner, which improves the display effect of the screen.

Description of drawings

FIG. 1 is a luminescence simulation diagram of a pixel unit in the FFS display mode in the prior art;

FIG. 2A is a top view structural diagram of a pixel unit in the FFS driving mode in the prior art;

2B is a schematic cross-sectional view along AA' of a pixel unit in the FFS driving mode in the prior art;

FIG. 3 is a schematic structural diagram of a pixel unit provided by Embodiment 1 of the present invention;

FIG. 4 is a schematic diagram of another implementation of the pixel unit provided by Embodiment 1 of the present invention;

FIG. 5 is a schematic cross-sectional view of a pixel unit along BB' according to Embodiment 1 of the present invention;

FIG. 6 is a schematic diagram of the positions of via holes in the pixel unit provided by Embodiment 1 of the present invention;

FIG. 7 is a schematic top view structural diagram of a pixel unit provided by Embodiment 2 of the present invention;

FIG. 8 is a schematic top view of another implementation of the pixel unit provided by Embodiment 2 of the present invention;

Fig. 9 is a schematic cross-sectional view along BB' of the top view shown in Fig. 8;

FIG. 10 is a schematic diagram of vias located above the data lines;

Fig. 11 is a schematic cross-sectional view along BB' of the top view shown in Fig. 8;

Fig. 12 is a schematic cross-sectional view along CC' of the top view shown in Fig. 8;

FIG. 13 is a schematic diagram of an array structure composed of a plurality of pixel units provided by Embodiment 3 of the present invention;

FIG. 14 is a schematic diagram of the via hole 70 located above the scanning line;

FIG. 15 is a schematic diagram of another implementation manner of Embodiment 3 of the present invention;

Fig. 16 is a comparative schematic diagram of the electric field intensity Ex in the X direction of the prior art and the technology of the present invention;

Fig. 17 is a schematic diagram comparing the electric field intensity Ey in the Y direction between the prior art and the technology of the present invention.

Detailed ways

In order to solve the problem of poor display effect in the display device in the prior art. The present invention provides a structure of a pixel unit, the pixel unit comprising: a first electrode, a second electrode and a shielding electrode; the first electrode is a planar structure; a first insulating layer is formed on the first electrode ; The second electrode is formed on the first insulating layer, and the second electrode includes a plurality of strip-shaped electrodes, and the plurality of strip-shaped electrodes are arranged at intervals; the plurality of strip-shaped electrodes in the second electrode A shielding electrode is provided at the end. The embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Embodiment one

Please refer to FIG. 3 , which is a schematic top view structural diagram of a pixel unit provided by Embodiment 1 of the present invention. As shown in the figure, the pixel unit provided by Embodiment 1 includes: a data line 210, a scan line 220, a TFT 12, a first electrode 40, a second electrode 50, and a shielding electrode 60, and the first electrode 40 and the second electrode 50 form Infield.

Specifically, the first electrode 40 is a planar electrode, the second electrode 50 includes a plurality of strip electrodes 500 , and a first insulating layer (not shown) for insulation is between the first electrode 40 and the second electrode 50 . In the first embodiment, the second electrode 50 is a pixel electrode, and the first electrode 40 is a common electrode. The plurality of strip electrodes 500 of the second electrode 50 are arranged at intervals, one end of the plurality of strip electrodes 500 of the second electrode 50 is connected to the drain of the TFT 12 , and the other end is open. A shield electrode 60 is provided at an end of the plurality of strip electrodes 500 of the second electrode 50 .

As shown in FIG. 3 , in Embodiment 1, the shielding electrode 60 is arranged between the ends of the strip electrodes 500 of the second electrode 50 , and the ends of the strip electrodes 500 of the second electrode 50 are shielded by the shielding electrode 60 The y-direction electric field generated between them. Wherein, the number of shielding electrodes 60 is equal to the number of spaces between every two adjacent strip electrodes 500 in the second electrode 50 , and its size is equal to the space between every two adjacent strip electrodes 500 of the second electrode 50 . Wherein, the end of the plurality of strip electrodes 500 of the second electrode 50 is the end of the second electrode 50 away from the thin film transistor.

Please refer to FIG. 4 , which is a schematic top view structural diagram of another implementation manner of the pixel unit provided by Embodiment 1 of the present invention. In another implementation manner of Embodiment 1 of the present invention, the shielding electrode 60 is arranged between and at each strip-shaped electrode 500 of the second electrode 50, and each strip of the second electrode 50 is shielded by the shielding electrode 60. The y-direction electric field generated at the end of the bar-shaped electrode 500, wherein, because the size of the shielding electrode 60 is much larger than the size between the outer edges of the two outermost strip-shaped electrodes 500 of the second electrode 50, the aperture ratio of the system will be reduced, so the shielding The size of the electrode 60 is approximately equal to the size between the outer edges of the two outermost strip electrodes 500 of the second electrode 50 . Compared with the first way of setting the shielding electrode 60, when the second way of setting the shielding electrode 60 is adopted, since the size of the shielding electrode 60 is equal to the distance between the outer edges of the two outermost strip electrodes 500 of the second electrode 50 Therefore, the electric field in the y direction generated by the arc-shaped electric field E generated at the end of each strip electrode 500 of the second electrode 50 can be more reliably shielded, thereby reducing the black area of abnormal display.

The shielding electrode 60 may be a floating electrode, or a voltage may be applied to the shielding electrode 60 , preferably, the shielding electrode 60 is applied with a voltage, and its voltage value is equal to the voltage value of the first electrode 40 of the pixel unit. Referring to FIG. 5 , which is a schematic cross-sectional view along BB' of the top view shown in FIG. 4 , since the first electrode 40 is a planar electrode, the shielding electrode 60 located above the first electrode 40 can pass through the via hole penetrating the first insulating layer 30 70 is electrically connected with it. The shielding electrode 60 is connected to the potential of the first electrode 40 , and the effect of shielding the electric field in the y direction at the end of the second electrode 50 is better.

Referring to FIG. 6 , the via hole 70 is located above the data line 210, and the shield electrode 60 is electrically connected to the first electrode 40 through the via hole 70; or, the via hole 70 is located above the scan line 220, and the shield electrode 60 passes through the via hole 70. The via hole 70 is electrically connected to the first electrode 40 . Since the top of the data line 210 and the top of the scan line 220 are non-display areas of the display device, the adoption of the above technical solution avoids affecting the display effect of the display device. The above-mentioned via hole 70 may be a circular via hole, may also be a rectangular via hole, and may also be an irregular-shaped via hole; when the via hole 70 is a circular via hole, its diameter is at least 3 microns.

Embodiment two

Please refer to FIG. 7 , which is a schematic top view structural diagram of a pixel unit provided by Embodiment 2 of the present invention. As shown in the figure, the pixel unit provided in Embodiment 2 includes: data line 210, scan line 220, TFT 12, first electrode 40, second electrode 50, shielding electrode 60, the first electrode 40 and the second electrode 50 form an in-plane field.

Specifically, the first electrode 40 is a planar electrode, the second electrode 50 includes a plurality of strip electrodes 500 and connecting electrodes 510, and a first insulating layer that plays an insulating role is also included between the first electrode 40 and the second electrode 50 (not shown). The plurality of strip electrodes 500 of the second electrode 50 are arranged at intervals. In the second embodiment, the second electrode 50 is a pixel electrode, and the first electrode 40 is a common electrode. One end of the plurality of strip electrodes 500 of the second electrode 50 is connected with the drain of the TFT 12, and the other end is connected with the connecting electrode 510; The strip electrodes 500 are connected together. A shielding electrode 60 is disposed at the end of the strip electrode 500 of the second electrode 50 .

Referring to FIG. 7 , in the second embodiment, the shielding electrode 60 is disposed between and at each strip electrode 500 of the second electrode 50 , and the shielding electrode 60 does not cover the connection electrode 510 . The y-direction electric field generated by the end of the strip electrode 500 and the connecting electrode 510 of the second electrode 50 is shielded by the shielding electrode 60 . Wherein, the size of the shielding electrode 60 is approximately equal to the size between the outer edges of the connecting electrodes 510 of the second electrode 50 , which avoids the problem of reducing the aperture ratio of the system when the size of the shielding electrode 60 is set too large.

Please refer to FIG. 8 , which is a schematic top view structural diagram of another implementation manner of the pixel unit provided by Embodiment 2 of the present invention. In another implementation of Embodiment 2 of the present invention, the shielding electrode 60 is arranged between and at each strip-shaped electrode 500 of the second electrode 50 , and the shielding electrode 60 covers the connection of the second electrode 50 The electrode 510 shields the y-direction electric field generated by the end of the strip electrode 500 and the connecting electrode 510 of the second electrode 50 through the shielding electrode 60 . Wherein, the size of the shielding electrode 60 is approximately equal to the size between the outer edges of the connecting electrodes 510 of the second electrode 50 , which avoids the problem of reducing the aperture ratio of the system when the size of the shielding electrode 60 is set too large.

Please refer to FIG. 9 , which is a schematic cross-sectional view of the top view shown in FIG. 8 along BB'. The shielding electrode 60 covers the connecting electrode 510. A second insulating layer 80 is further provided between the second electrode 50 and the second electrode 50 . Since the first electrode 40 is a planar electrode, the shielding electrode 60 above the first electrode 40 can be electrically connected to it through the via hole 70 penetrating the first insulating layer 30 . The potential connection between the shielding electrode 60 and the first electrode 40 is more effective in shielding the electric field in the y direction at the end of the second electrode 50 .

Referring to FIG. 10 , the via hole 70 is located above the data line 210, and the shield electrode 60 is electrically connected to the first electrode 40 through the via hole 70; or, the via hole 70 is located above the scan line 220, and the shield electrode 60 passes through the via hole 70. The via hole 70 is electrically connected to the first electrode 40 . Since the top of the data line 210 and the top of the scan line 220 are non-display areas of the display device, the adoption of the above technical solution avoids affecting the display effect of the display device. The above-mentioned via hole 70 may be a circular via hole, may also be a rectangular via hole, and may also be an irregular-shaped via hole; when the via hole 70 is a circular via hole, its diameter is at least 3 microns.

Please refer to FIG. 11 , which is a schematic cross-sectional view along BB' of the top view shown in FIG. 8 . As shown in the figure, the shielding electrode 60 also covers the end face of the connecting electrode 510 towards the inside of the second electrode 50, that is, the shielding electrode 60 approximately wraps around the connecting electrode 510, so as to reliably weaken the y-direction generated by the ends of the strip electrodes 500 of the second electrode 50. The electric field further improves the display effect of the display device.

Please refer to FIG. 12 , which is a schematic cross-sectional view along CC′ of the top view shown in FIG. 8 . As shown in the figure, the second insulating layer 80 wraps the second electrode 50 , and the angle between a side T1 of the second insulating layer 80 away from the connecting electrode 510 and a horizontal plane T2 of the first insulating layer 30 is greater than or equal to 90 degrees. Since the shielding electrode 60 needs to be formed with the second insulating layer 80 as a reference plane during the formation of the shielding electrode 60, when the angle between the side surface T1 of the second insulating layer 80 and the horizontal plane T2 of the first insulating layer 30 is greater than At 90 degrees, it is more beneficial to make the formed shielding electrode 60 reliably cover the connecting electrode 510 of the second electrode 50, thereby ensuring the shielding effect of the shielding electrode 60 on the electric field generated by each strip electrode 500 at the end of the second electrode 50, reducing Abnormally displayed black areas.

Embodiment three

Please refer to FIG. 13 , which is a schematic diagram of an array structure composed of a plurality of pixel units provided by Embodiment 3 of the present invention. As shown in the figure, the array structure provided by Embodiment 3 includes a plurality of data lines 210 , a plurality of scan lines 220 , and a plurality of pixel units 1 defined by intersections of the plurality of data lines 210 and the plurality of scan lines 220 .

Specifically, each pixel unit 1 includes a first electrode 40 , a second electrode 50 and a shielding electrode 60 , and an in-plane field is formed between the first electrode 40 and the second electrode 50 . The first electrode 40 is a planar electrode, the second electrode 50 includes a plurality of strip electrodes 500 , and a first insulating layer (not shown) for insulation is between the first electrode 40 and the second electrode 50 . The plurality of strip electrodes 500 of the second electrode 50 are arranged at intervals. In the third embodiment, the second electrode 50 is a pixel electrode, and the first electrode 40 is a common electrode. One end of the plurality of strip electrodes 500 of the second electrode 50 is connected to the drain of the TFT12, and the other end is open; or, one end of the plurality of strip electrodes 500 of the second electrode 50 is connected to the drain of the TFT12. The other end is connected to the connection electrode (not shown). A shielding electrode 60 is provided at the ends of the plurality of strip electrodes 500 of the second electrode 50 to shield the electric field component in the y direction generated between the ends of the plurality of strip electrodes 500 of the second electrode 50, reducing the black of abnormal display area.

Referring to FIG. 13 , in the third embodiment, taking the shielding electrode 60 and the second electrode 50 on the same layer as an example, a voltage is applied to the shielding electrode 60 , and the value of the applied voltage is equal to that of the first electrode 40 of the pixel unit 1. Voltage value. Since the first electrode 40 is a planar electrode, the shielding electrode located above the first electrode 40 can be electrically connected to the first electrode 40 through the via hole 70 penetrating the first insulating layer. Wherein, the via hole 70 is located above the data line 210, and the shielding electrodes 60 of the pixel unit 1a, the pixel unit 1b, the pixel unit 1c, and the pixel unit 1d are connected to the same via hole 70 through the connection channel 90 located above the data line 210, and The via hole 70 is electrically connected to the first electrode 40 . With the above technical solution, multiple pixel units 1 are connected to the first electrode 40 through the same via hole 70, thereby simplifying the manufacturing process.

Please refer to FIG. 14 , in the third embodiment, the via hole 70 may also be located above the scan line 220 . At this time, if the voltage value applied to the shielding electrode 60 is equal to the voltage value of the first electrode 40 of the pixel unit 1, the shielding electrodes 60 of the pixel unit 1a and the pixel unit 1b are connected through the connection channel 90 above the scanning line 220 . The same via hole 70 is electrically connected to the first electrode 40 through the via hole 70 .

Please refer to FIG. 15 , which is a schematic diagram of another implementation manner of Embodiment 3 of the present invention. In another implementation of Embodiment 3 of the present invention, the shielding electrodes 60 of all pixel units 1 located in the same row are connected to each other, and the above-mentioned interconnected shielding electrodes 60 are connected to the first electrode outside the array structure 40 , making the voltage value applied to the shielding electrode 60 equal to the voltage value of the first electrode 40 of the pixel unit 1 .

An embodiment of the present invention provides a liquid crystal display device, which includes the above-mentioned array structure, a color filter substrate, and a liquid crystal layer disposed between the array structure and the color filter substrate.

Specifically, to match the above-mentioned array structure, a black matrix is provided on the inner surface of the color filter substrate 3 of the liquid crystal display device facing the array structure, and in the direction of light transmission, the opaque part of the black matrix blocks the shielding electrode .

Please refer to Fig. 16 and Fig. 17, Fig. 16 is a schematic diagram comparing the electric field intensity Ex in the X direction between the prior art and the technology of the present invention, and Fig. 17 is a schematic diagram comparing the electric field intensity Ey in the Y direction between the prior art and the technology of the present invention. It can be seen from Fig. 16 and Fig. 17 that compared with the prior art, the electric field intensity Ex of the present invention is increased and the electric field intensity Ey is decreased, which can effectively suppress the area of the black area displayed abnormally and improve the display effect.

To sum up, in the embodiment of the present invention, the pixel unit includes: a first electrode, a second electrode and a shielding electrode; the first electrode has a planar structure; a first insulating layer is formed on the first electrode. layer; the second electrode is formed on the first insulating layer, and the second electrode includes a plurality of strip-shaped electrodes, and the plurality of strip-shaped electrodes are arranged at intervals; the plurality of strip-shaped electrodes of the second electrode A shield electrode is provided at the end of the electrode. With the above technical solution, when there is an electrical signal in the pixel unit, due to the existence of the shielding electrode, the electric field in the Ey direction generated by the end of the strip electrode of the second electrode will be shielded, thereby effectively avoiding the domain line phenomenon and ensuring the pixel unit The display molecules corresponding to all the display areas can be rotated according to the preset method, which improves the display effect of the screen.

Apparently, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. In this way, if the modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (15)

1. A pixel unit structure, the pixel unit comprising: a first electrode, a second electrode and a shielding electrode; The first electrode is a planar structure; A first insulating layer is formed on the first electrode; The second electrode is formed on the first insulating layer, and the second electrode includes a plurality of strip electrodes, and the plurality of strip electrodes are arranged at intervals; A shielding electrode is provided at an end of the plurality of strip electrodes of the second electrode. 2 . The pixel unit structure according to claim 1 , wherein the shielding electrode is arranged between the strip electrodes of the second electrode. 3 . 3 . The pixel unit structure according to claim 1 , wherein the shielding electrode is disposed between and at the strip electrodes of the second electrode. 4 . 4. The pixel unit structure according to claim 1, wherein the shielding electrode and the second electrode are located on the same conductive layer. 5 . The pixel unit structure according to claim 1 , wherein the second electrode further comprises a connection electrode, and the connection electrode connects a plurality of strip electrodes together at the end of the second electrode. 6 . The pixel unit structure according to claim 5 , wherein the shielding electrode covers the connecting electrode, and a second insulating layer is disposed between the shielding electrode and the connecting electrode. 7 . The pixel unit structure according to claim 6 , wherein the shielding electrode also covers an end face of the connecting electrode facing inside of the second electrode. 8. The pixel unit structure according to claim 1, wherein the shielding electrode is electrically connected to the first electrode through a via hole in the first insulating layer. 9. An array structure of pixel units, comprising a plurality of pixel units defined by intersections of a plurality of scanning lines and data lines, wherein the pixel units are the pixel units described in any one of claims 1-8. 10. The array structure according to claim 9, wherein the via hole is located above the data line; or, the via hole is located above the scan line. 11. The array structure according to claim 9, wherein the shielding electrodes of a plurality of adjacent pixel units are connected together, and are electrically connected to the first electrode through the same via hole. 12. The array structure according to claim 9, wherein the shielding electrodes of the pixel units in the same row are connected to each other, and are electrically connected to the signal of the first electrode outside the pixel unit array. 13. The array structure according to claim 9, wherein the shielding electrode is a transparent conductive layer; or, the shielding electrode is a metal layer. 14. A liquid crystal display device, characterized by comprising the array structure according to any one of claims 9 to 13, further comprising a color filter substrate, and a liquid crystal layer arranged between the array substrate and the color filter substrate. 15. The liquid crystal display device according to claim 14, wherein a black matrix is arranged on the inner surface of the color filter substrate facing the array substrate, and in the direction of light transmission, the black matrix The opaque portion of the shield electrode is shielded.