Display panel

Abstract

The present invention provides a display panel, wherein an electrode layer of the display panel includes a first main electrode extending along a first direction, a plurality of first and second branch electrodes located on both sides of the first main electrode, and a second main electrode. The second main electrode is staggered with the first main electrode, and the angle between the first main electrode and the second main electrode is between 80 degrees and 100 degrees. One of the first branch electrodes extends along a third direction, one of the second branch electrodes extends along a fourth direction, and the other of the second branch electrodes extends along the third direction, and the one of the second branch electrodes and the other of the second branch electrodes are respectively located on both sides of the second main electrode. The one of the first branch electrodes and the one of the second branch electrodes respectively have a first arc-shaped side edge and a second arc-shaped side edge adjacent to the first main electrode; the first direction, the third direction, and the fourth direction are all different from each other.

Description

[0001] The present invention is a divisional application of the invention with application number 201410767490.8, application date December 12, 2014, and invention name “Display Panel and Display Device”. Technical Field

[0002] The present invention relates to a display panel and a display device, and more particularly to a flat display panel and a flat display device. Background Art

[0003] With the advancement of technology, flat panel display devices have been widely used in various fields. In particular, liquid crystal display devices have gradually replaced traditional cathode ray tube display devices due to their superior characteristics such as light weight, low power consumption and no radiation. They are now used in many types of electronic products, such as mobile phones, portable multimedia devices, notebook computers, LCD TVs and LCD monitors.

[0004] Liquid crystal display manufacturers are currently developing multi-domain vertical alignment (MVA) technology for wide viewing angles in thin-film transistor liquid crystal displays (TFT LCDs). Polymer-stabilized alignment (PSA), also known as polymer-sustained alignment (PSA), is a mature and mass-produced technology for improving optical properties such as aperture ratio and contrast. PSA technology involves mixing a photoreactive monomer during the panel's one-drop filling (ODF) process. After applying an electrical current and exposing the mixture to ultraviolet light, the monomer undergoes a chemical reaction, causing it to align according to the pattern of the transparent conductive layer on the thin-film transistor substrate. This chemical reaction then aligns the liquid crystal.

[0005] In the prior art, the transparent conductive layer on a thin-film transistor substrate typically comprises a combination of a main electrode and branch electrodes. In industry designs, the branch electrodes are connected to the main electrode at an angle, so the connection point (also known as the turning point) is typically sharp, resulting in an angle (e.g., 45 degrees or 135 degrees) between the branch electrode and the main electrode. However, the sharp turning point causes the liquid crystal molecules to align abnormally during the power-on step due to the discontinuous electric field at the turning point. Therefore, the monomer chemical reaction time (curing time) must be increased to ensure that the liquid crystal molecules at the turning point are stably pre-tilted at a certain angle. This increases process time and reduces product competitiveness. Summary of the Invention

[0006] An object of the present invention is to provide a display panel and a display device that can improve the abnormal liquid crystal alignment caused by electric field discontinuity at the turning points of branch electrodes of an electrode layer, thereby reducing process time and improving product competitiveness.

[0007] To achieve the above-mentioned objective, a display panel according to the present invention includes a first substrate, a second substrate disposed opposite to the first substrate, and an electrode layer. The electrode layer is disposed on the first substrate and faces the second substrate, and includes a first main electrode extending along a first direction and a plurality of first branch electrodes and a plurality of second branch electrodes located on both sides of the first main electrode. The first branch electrodes or the second branch electrodes are separated by a distance T. One of the first branch electrodes and one of the second branch electrodes have a first arcuate side and a second arcuate side adjacent to the first main electrode. The first arcuate side and the second arcuate side have a first shortest distance A along a second direction perpendicular to the first direction. The first arcuate side has a first vertex, and the second arcuate side has a second vertex. The first vertex is the highest point or the lowest point of the first arcuate side in the first direction, and the second vertex is the highest point or the lowest point of the second arcuate side in the first direction. The first vertex and the second vertex have a second shortest distance B along the second direction. Wherein, A, B, and T satisfy the following equation: 0.5T≤(BA)≤T, and the units of A, B, and T are micrometers.

[0008] To achieve the above-mentioned purpose, a display device according to the present invention includes a display panel and a backlight module. The backlight module is disposed opposite to the display panel. The display panel comprises a first substrate, a second substrate disposed opposite the first substrate, and an electrode layer. The electrode layer is disposed on the first substrate and faces the second substrate, and includes a first main electrode extending in a first direction and a plurality of first branch electrodes and a plurality of second branch electrodes located on either side of the first main electrode. The first branch electrodes or the second branch electrodes are spaced a distance T apart from each other. One of the first branch electrodes and one of the second branch electrodes have a first arcuate side and a second arcuate side adjacent to the first main electrode. The first arcuate side and the second arcuate side have a first shortest distance A along a second direction perpendicular to the first direction. The first arcuate side has a first vertex, and the second arcuate side has a second vertex. The first vertex is the highest point or the lowest point of the first arcuate side in the first direction, and the second vertex is the highest point or the lowest point of the second arcuate side in the first direction. The first vertex and the second vertex have a second shortest distance B along the second direction. A, B, and T satisfy the following equation: 0.5T≤(BA)≤T, and the units of A, B, and T are micrometers.

[0009] In one embodiment, A, B, and T further satisfy the following equation: 0.6T≤(BA)≤0.9T.

[0010] In one embodiment, two adjacent first branch electrodes are spaced apart from each other by the distance along a third direction, and two adjacent second branch electrodes are spaced apart from each other by the distance along a fourth direction, and the third direction is substantially perpendicular to the fourth direction.

[0011] In one embodiment, the first arc-shaped side and the second arc-shaped side are oppositely disposed.

[0012] In one embodiment, the first arc-shaped side and the second arc-shaped side are staggered.

[0013] In one embodiment, the electrode layer further includes a second trunk electrode interlaced with the first trunk electrode, and the angle between the first trunk electrode and the second trunk electrode is between 80 degrees and 100 degrees.

[0014] In one embodiment, one of the first branch electrode or the second branch electrode further has a straight side, and an angle between the straight side and the first trunk electrode or the second trunk electrode is between 5 degrees and 85 degrees.

[0015] As described above, in the display panel and display device of the present invention, the electrode layer includes a first main electrode extending along a first direction and a plurality of first branch electrodes and a plurality of second branch electrodes located on either side of the first main electrode, and the first branch electrodes or the second branch electrodes are spaced apart by a distance T. Furthermore, the first arcuate side and the second arcuate side have a first minimum distance A along a second direction perpendicular to the first direction, and the first vertex of the first arcuate side is the highest or lowest point of the first arcuate side in the first direction, and the second vertex of the second arcuate side is the highest or lowest point of the second arcuate side in the first direction, and the first vertex and the second vertex have a second shortest distance B along the second direction. When A, B, and T satisfy the equation: 0.5T≤(BA)≤T, compared to the prior art, the abnormal liquid crystal alignment caused by electric field discontinuity at the turning points of the branch electrodes of the electrode layer can be improved, thereby reducing process time and improving product competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FIG. 1 is a schematic diagram of a display panel according to a preferred embodiment of the present invention.

[0017] Figure 2A for Figure 1 Schematic diagram of the electrode pattern of an electrode layer in a display panel.

[0018] Figure 2B for Figure 2A An enlarged schematic diagram of an area.

[0019] Figure 3 FIG. 4 is a schematic diagram of an electrode pattern of an electrode layer according to another embodiment.

[0020] Figure 4 FIG. 1 is a schematic diagram of a display device according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0021] A display panel and a display device according to preferred embodiments of the present invention will be described below with reference to the accompanying drawings, wherein the same elements will be represented by the same reference symbols.

[0022] Please refer to Figure 1 、 Figure 2A and Figure 2B As shown, Figure 1 is a schematic diagram of a display panel 1 according to a preferred embodiment of the present invention. Figure 2A for Figure 1 Schematic diagram of the electrode pattern of the electrode layer 13 in the display panel 1, and Figure 2B for Figure 2A Schematic diagram of the enlarged area P.

[0023] The display panel 1 of this embodiment is, for example but not limited to, an in-plane switch (IPS) liquid crystal display panel, a fringe field switching (FFS) liquid crystal display panel, a vertical alignment mode (VA mode) liquid crystal display panel, or a 3D liquid crystal display panel.

[0024] like Figure 1 As shown, the display panel 1 includes a first substrate 11, a second substrate 12, and an electrode layer 13. Furthermore, the display panel 1 may also include a liquid crystal layer 14 (liquid crystal molecules are not shown). The display panel 1 is used, for example but not limited to, in a smartphone, tablet computer, or other electronic device. When light passes through the display panel 1, each pixel (sub-pixel) of the display panel 1 displays colors to form an image.

[0025] The first substrate 11 and the second substrate 12 are disposed opposite to each other, and the liquid crystal layer 14 is sandwiched between the first substrate 11 and the second substrate 12. The first substrate 11 and the second substrate 12 can be made of a transparent material, such as a glass substrate, a quartz substrate, or a plastic substrate, without limitation.

[0026] The electrode layer 13 is disposed on the first substrate 11 and faces the second substrate 12. The electrode layer 13 is a transparent conductive layer, and its material is, for example, but not limited to, indium-tin oxide (ITO) or indium-zinc oxide (IZO). In this embodiment, the electrode layer 13 is the pixel electrode layer of the display panel 1 and is electrically connected to the data line (not shown). Figure 2A Show only Figure 1 A portion of the electrode layer 13 (still labeled 13 ) is shown, and what is displayed is the pattern of the pixel electrode of one sub-pixel of the display panel 1 .

[0027] In addition, the display panel 1 may further include a thin film transistor array, a color filter array, and a black matrix layer (not shown). The thin film transistor array is disposed on the first substrate 11, and the color filter array or the black matrix layer may be disposed on the first substrate 11 or the second substrate 12. The thin film transistor array, the color filter array, and the liquid crystal layer 14 may form a pixel array. In one embodiment, the black matrix layer and the color filter array may be disposed separately on the second substrate 12. However, in another embodiment, the black matrix layer or the color filter array may be disposed separately on the first substrate 11, forming a BOA (BM on array) substrate or a COA (color filter on array) substrate, without limitation. Furthermore, the display panel 1 may further include a plurality of scan lines and a plurality of data lines (not shown). The scan lines and the data lines are arranged in an interlaced manner, for example, perpendicular to each other, to define the pixel array region. The pixel array includes a plurality of (sub)pixels, and the (sub)pixels are arranged in a matrix.

[0028] like Figure 2A and Figure 2B As shown, the electrode layer 13 includes a first trunk electrode 131, a second trunk electrode 132, and a plurality of first branch electrodes 133 and a plurality of second branch electrodes 134 located on both sides of the first trunk electrode 131. The first trunk electrode 131 extends along a first direction D1, and the second trunk electrode 132 extends along a second direction D2, and the first direction D1 is substantially perpendicular to the second direction D2. In this embodiment, the first direction D1 is Figure 2A The up and down directions, and the second direction D2 is Figure 2A However, in different embodiments, the first direction D1 may also be Figure 2A The left and right directions, and the second direction D2 can also be Figure 2A The present invention does not limit the up and down directions.

[0029] The first trunk electrode 131 and the second trunk electrode 132 are interlaced, and the angle between the first trunk electrode 131 and the second trunk electrode 132 can be between 80 degrees and 100 degrees. For example, the connecting portion of the first trunk electrode 131 and the second trunk electrode 132 is located in the middle region of the electrode layer 13, and the angle between the first trunk electrode 131 and the second trunk electrode 132 is substantially 90 degrees (i.e., the first direction D1 and the second direction D2 are substantially perpendicular). Because the first trunk electrode 131 and the second trunk electrode 132 are interlaced, and their connecting portion is located in the middle region, the electrode layer 13 can be divided into four electrode regions (having four domains) by the first trunk electrode 131 and the second trunk electrode 132. In addition, the electrode layer 13 of this embodiment is also surrounded by a surrounding electrode 135, and the surrounding electrode 135 has four surrounding portions 135a, 135b, 135c, and 135d, wherein the surrounding portions 135a and 135b are respectively connected to the first trunk electrode 131, the second trunk electrode 132, and the second branch electrodes 134, and the surrounding portions 135c and 135d are respectively connected to the first trunk electrode 131, the second trunk electrode 132, and the first branch electrodes 133, to form a closed electrode layer 13.

[0030] like Figure 2B As shown, the first branch electrodes 133 or the second branch electrodes 134 are spaced apart by a distance T. Here, the distance T is between two adjacent first branch electrodes 133 along a third direction D3, and the distance T is between two adjacent second branch electrodes 134 along a fourth direction D4. The third direction D3 and the fourth direction D4 are substantially perpendicular to each other. The first branch electrodes 133 are connected to the first trunk electrode 131 or the second trunk electrode 132, and the second branch electrodes 134 are connected to the first trunk electrode 131 or the second trunk electrode 132. Here, a portion of the first branch electrodes 133 are connected to the first trunk electrode 131, a portion of the first branch electrodes 133 are connected to the second trunk electrode 132, a portion of the second branch electrodes 134 are connected to the first trunk electrode 131, and a portion of the second branch electrodes 134 are connected to the second trunk electrode 132.

[0031] In addition, one of the first branch electrodes 133 and one of the second branch electrodes 134 have a first arcuate side C1 and a second arcuate side C2 adjacent to the first main electrode 131. In this embodiment, the first branch electrodes 133 each have a first arcuate side C1 adjacent to the first main electrode 131, and the second branch electrodes 134 each have a second arcuate side C2 adjacent to the first main electrode 131. The first arcuate side C1 and the second arcuate side C2 are disposed opposite each other. However, in different embodiments, the first arcuate side C1 and the second arcuate side C2 may also be disposed in an offset manner in the first direction D1 (i.e., offset up and down, not opposite each other), and the present invention is not limited thereto. In addition to the first curved side C1 and the second curved side C2, the first branch electrode 133 and the second branch electrode 134 each further include at least one linear side L. The included angle θ between the extension of the linear side L and the first trunk electrode 131 or the second trunk electrode 132 can be between 5 degrees and 85 degrees. Here, the included angle θ between the extension of the linear side L of the first branch electrode 133 (and the second branch electrode 134) and the first trunk electrode 131 is 45 degrees, for example.

[0032] In addition, the first arc-shaped side C1 and the second arc-shaped side C2 have a first shortest distance A along the second direction D2. Figure 2B As shown, since the first arcuate side C1 and the second arcuate side C2 are arranged relative to each other, the shortest distance between the two along the second direction D2 is defined as A. However, in other embodiments, if other conditions remain unchanged, since it is defined as along the second direction D2, when the first arcuate side C1 and the second arcuate side C2 are arranged in an offset manner, the first shortest distance A between the two along the second direction D2 is still the same as Figure 2B Furthermore, in some embodiments, the first shortest distance A may be defined as follows: the first shortest distance A may be the width of the first trunk electrode 131 along the second direction D2; or, two adjacent first branch electrodes 133 may have a first gap, two adjacent second branch electrodes 134 may have a second gap, and the first shortest distance A may be the shortest distance between the first gap and the second gap along the second direction D2. The present invention does not limit the definition of the first shortest distance A.

[0033] In addition, the first arc-shaped side C1 has a first vertex V1, and the second arc-shaped side C2 has a second vertex V2. The first vertex V1 is the highest point or the lowest point of the first arc-shaped side C1 in the first direction D1, and the second vertex V2 is the highest point or the lowest point of the second arc-shaped side C2 in the first direction D1, and the first vertex V1 and the second vertex V2 have a second shortest distance B along the second direction D2. Here, the first vertex V1 is the highest point of the first arc-shaped side C1 in the first direction D1, and the second vertex V2 is also the highest point of the second arc-shaped side C2 in the first direction D1. It is particularly noted that the first direction D1 of this embodiment is Figure 2B However, in different embodiments, if the first direction D1 is a horizontal direction, the viewing angle of the electrode layer 13 is simply rotated 90 degrees. The first vertex V1 can also be regarded as the highest point or the lowest point of the first arc-shaped side C1 in the first direction D1, and the second vertex V2 can also be regarded as the highest point or the lowest point of the second arc-shaped side C2 in the first direction D1.

[0034] Through actual experimental data, it was found that in the prior art, when the turning point connecting the branch electrode to the main electrode is designed as a sharp angle (i.e., (B-A) = 0), the transmittance of the display panel 1 is higher, but the abnormal alignment of the liquid crystal molecules is more common. If the turning point is designed as a curved side, the value of (B-A) / T will increase, and the abnormal alignment of the liquid crystal molecules can be improved. However, when the value of (B-A) / T rises to 1 or exceeds 1, although the abnormal alignment of the liquid crystal molecules can be further improved, the transmittance tends to decrease significantly. Therefore, by changing the relative size of A and B (i.e., different curved side designs), the optimal balance between transmittance and abnormal alignment of the liquid crystal molecules can be achieved.

[0035] Therefore, in the display panel 1 of this embodiment, the first shortest distance A, the second shortest distance B, and the spacing T between the first branch electrodes 133 (or the second branch electrodes 134) satisfy the following equation: 0.5T≤(BA)≤T, where A, B, and T are expressed in micrometers. This achieves a better balance between transmittance and abnormal alignment of liquid crystal molecules. This improves the alignment of liquid crystal molecules caused by electric field discontinuities at the junctions between the branch electrodes and the main electrodes, a phenomenon commonly encountered in the prior art. This reduces monomer chemical reaction time and enhances product competitiveness. This improvement becomes more pronounced with higher resolution (ppi). Preferably, if A, B, and T also satisfy the following equation: 0.6T≤(BA)≤0.9T, even greater improvement is achieved.

[0036] In addition, please refer to Figure 3 , which is a schematic diagram of an electrode pattern of the electrode layer 13a in another embodiment.

[0037] The electrode layer 13a and Figure 2A The main difference between the electrode layer 13 and the electrode layer 13 is that the electrode layer 13 a does not have the surrounding electrode 135 of the electrode layer 13 , and therefore, the electrode layer 13 a is an open electrode layer.

[0038] In addition, other technical features of the electrode layer 13a can refer to the above-mentioned electrode layer 13 and will not be repeated here.

[0039] In addition, please refer to Figure 4 , which is a schematic diagram of a display device 2 according to a preferred embodiment of the present invention.

[0040] The display device 2 includes a display panel 3 and a backlight module 4. The display panel 3 and backlight module 4 are disposed opposite each other. The display panel 3 has all the features of the display panel 1 and its variations, and will not be further described here. When light E emitted by the backlight module 4 passes through the display panel 3, each pixel (sub-pixel) of the display panel 3 displays color, forming an image.

[0041] In summary, in the display panel and display device of the present invention, the electrode layer includes a first main electrode extending along a first direction and a plurality of first branch electrodes and a plurality of second branch electrodes located on either side of the first main electrode, and the first branch electrodes or the second branch electrodes are spaced apart by a distance T. Furthermore, the first curved side and the second curved side have a first minimum distance A along a second direction perpendicular to the first direction, and the first vertex of the first curved side is the highest or lowest point of the first curved side in the first direction, and the second vertex of the second curved side is the highest or lowest point of the second curved side in the first direction, and the first vertex and the second vertex have a second minimum distance B along the second direction. When A, B, and T satisfy the equation: 0.5T≤(BA)≤T, compared to the prior art, the abnormal liquid crystal alignment caused by electric field discontinuity at the turning points of the branch electrodes of the electrode layer can be improved, thereby reducing process time and improving product competitiveness.

[0042] The above description is for illustrative purposes only and is not intended to be limiting. Any equivalent modifications or variations that do not depart from the spirit and scope of the present invention should be included in the scope of the patent application.

Claims

1. A display panel, characterized in that: The display panel includes: a first substrate; and an electrode layer disposed on the first substrate and comprising a first main electrode extending along a first direction, a plurality of first branch electrodes and a plurality of second branch electrodes located on both sides of the first main electrode, and a second main electrode, wherein the second main electrode is staggered with the first main electrode, and an angle between the first main electrode and the second main electrode is between 80 degrees and 100 degrees. One of the first branch electrodes extends along a third direction, one of the second branch electrodes extends along a fourth direction, and the other of the second branch electrodes extends along the third direction. The one of the second branch electrodes and the other of the second branch electrodes are respectively located on both sides of the second main electrode, and the first direction, the third direction, and the fourth direction are all different from each other. Among them, one of the first branch electrodes and one of the second branch electrodes respectively have a first arc-shaped side and a second arc-shaped side adjacent to the first main electrode, the first arc-shaped side and the second arc-shaped side respectively have a highest point in the first direction, the shortest distance between the first arc-shaped side and the second arc-shaped side along a second direction perpendicular to the first direction is A, the shortest distance between the highest point of the first arc-shaped side and the highest point of the second arc-shaped side along the second direction is B, and B>A, and a first gap is included between adjacent two of the first branch electrodes, the width of the first gap is T, and 0.5T≤(BA)≤T.

2. The display panel according to claim 1, wherein One of the first branch electrodes has a straight side, and the straight side is connected to the first arc-shaped side.

3. The display panel according to claim 2, wherein: An included angle between an extension line of the straight side and the first main electrode is between 5 degrees and 85 degrees.

4. The display panel according to claim 1, wherein: The first arc-shaped side and the second arc-shaped side are arranged opposite to each other.

5. The display panel according to claim 1, wherein The first arc-shaped side and the second arc-shaped side are staggered.

6. The display panel according to claim 1, wherein: It further includes multiple data lines and multiple scan lines, wherein the scan lines and the data lines are staggered to define a pixel array, the pixel array includes multiple sub-pixels, and the first main electrode, the second main electrode, the first branch electrodes and the second branch electrodes are arranged corresponding to one of the sub-pixels.

7. The display panel according to claim 1, wherein: The electrode layer is a transparent conductive layer.

8. The display panel according to claim 1, wherein: The electrode layer further includes a surrounding electrode, and the surrounding electrode connects the first trunk electrode and the second trunk electrode.

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