Display device

Abstract

A display device with high reliability, fast response speed, and high brightness includes a plurality of scan lines, a plurality of signal lines, a plurality of pixels, a pixel electrode, a common electrode having a stem portion and a plurality of branch portions, and a third wiring. An area in which the pixel electrode overlaps a first scan line is larger than an area in which the pixel electrode overlaps a second scan line. A first area of the third wiring has a width that is shorter than a width of the scan lines. The plurality of branch portions of the common electrode extend from the stem portion in the second direction.

Description

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to Japanese Patent Application No. 2022-045781, filed on March 22, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments of the present invention relate to display devices. Background Technology

[0004] As an example of a display device, an IPS (In-Plane-Switching) liquid crystal display device is known. In an IPS liquid crystal display device, a pixel electrode and a common electrode are disposed on one of a pair of substrates facing each other with a liquid crystal layer in between, and the orientation of the liquid crystal molecules in the liquid crystal layer is controlled by the transverse electric field generated between these electrodes. Furthermore, an FFS (Fringe Field-Switching) liquid crystal display device, which arranges the pixel electrode and the common electrode in different layers in the IPS mode, has been practically implemented. In this liquid crystal display device, the orientation of the liquid crystal molecules is controlled by the edge electric field generated between a pair of electrodes.

[0005] On the other hand, Patent Document 1 discloses a liquid crystal display device that accelerates the response speed by periodically forming regions in each pixel where liquid crystal molecules do not rotate. This configuration of the liquid crystal display device will be referred to as a high-speed response mode. Summary of the Invention

[0006] The purpose of this embodiment is to provide a display device with high reliability, fast response speed, and high brightness.

[0007] One embodiment of the display device includes:

[0008] Multiple scan lines extend in the first direction;

[0009] Multiple signal lines extend in a second direction that intersects with the aforementioned first direction;

[0010] Multiple pixels are located at the intersections of the aforementioned multiple signal lines and the aforementioned multiple scan lines;

[0011] A pixel electrode is disposed in a region divided by adjacent first and second scan lines among the plurality of scan lines and adjacent first and second signal lines among the plurality of signal lines.

[0012] A common electrode, comprising a main stem and multiple branches; and

[0013] The third wiring includes a first region that overlaps with the aforementioned plurality of scan lines and a second region that overlaps with the aforementioned plurality of signal lines.

[0014] The area where the pixel electrode overlaps with the first scan line is larger than the area where the pixel electrode overlaps with the second scan line.

[0015] The width of the first region of the third wiring is shorter than the width of the scan line.

[0016] The aforementioned multiple branches of the common electrode extend from the aforementioned main stem along the aforementioned second direction.

[0017] Furthermore, one embodiment of the display device includes:

[0018] Multiple scan lines extend in the first direction;

[0019] Multiple signal lines extend in a second direction that intersects with the aforementioned first direction;

[0020] Multiple pixels are located at the intersections of the aforementioned multiple signal lines and the aforementioned multiple scan lines;

[0021] A pixel electrode is disposed in a region divided by adjacent first and second scan lines among the plurality of scan lines and adjacent first and second signal lines among the plurality of signal lines.

[0022] A common electrode is provided, comprising a first main stem, multiple first branches, and a straight section.

[0023] The third cabling section has a second main branch and multiple second branches.

[0024] The area where the pixel electrode overlaps with the first scan line is larger than the area where the pixel electrode overlaps with the second scan line.

[0025] The first branch of the aforementioned common electrode extends from the aforementioned first main branch along the aforementioned second direction.

[0026] The second branch of the third wiring extends from the second main branch along the second direction.

[0027] The width of the second main branch of the third wiring described above is shorter than the width of the scan line described above.

[0028] One embodiment of the display device includes:

[0029] Multiple scan lines extend in the first direction;

[0030] Multiple signal lines extend in a second direction that intersects with the aforementioned first direction;

[0031] Multiple pixels are located at the intersections of the aforementioned multiple signal lines and the aforementioned multiple scan lines;

[0032] A pixel electrode is disposed in a region divided by adjacent first and second scan lines among the plurality of scan lines and adjacent first and second signal lines among the plurality of signal lines.

[0033] A common electrode, comprising a first main stem, multiple first branches, and protrusions; and

[0034] The third cabling section has a second main branch and multiple second branches.

[0035] The area where the pixel electrode overlaps with the first scan line is larger than the area where the pixel electrode overlaps with the second scan line.

[0036] The first branch of the aforementioned common electrode extends from the aforementioned first main branch along the aforementioned second direction.

[0037] The second branch of the third wiring extends from the second main branch along the second direction.

[0038] The width of the second main branch of the third wiring is shorter than the width of the scan line. Attached Figure Description

[0039] Figure 1 This is a diagram illustrating an example of the equivalent circuit of a display device.

[0040] Figure 2 This is a cross-sectional view showing an example of the structure of a display device.

[0041] Figure 3 This is a cross-sectional view showing an example of the structure of a substrate.

[0042] Figure 4 It is a planar diagram representing one example of the pixels of the comparison example.

[0043] Figure 5 This is a plan view showing an example of pixels in this embodiment.

[0044] Figure 6 It means Figure 5 The diagram shows the scan lines, signal lines, and drain electrode among the constituent elements.

[0045] Figure 7 It means Figure 5 The diagram shows the scan lines, signal lines, drain electrodes, and pixel electrodes among the constituent elements.

[0046] Figure 8 It means Figure 5The diagram shows the scan lines, signal lines, drain electrodes, pixel electrodes, and common electrodes among the constituent elements.

[0047] Figure 9 It means Figure 5 A plan view of the common electrode among the constituent elements shown.

[0048] Figure 10 This is a plan view showing an example of the configuration of the display device according to the embodiment.

[0049] Figure 11 It means Figure 10 The diagram shows the common electrode and wiring in the components shown.

[0050] Figure 12 It means Figure 10 The diagram shows a plan view of the components that share only the electrodes.

[0051] Figure 13 This is a plan view showing an example of the configuration of the display device according to the embodiment.

[0052] Figure 14 It means Figure 13 The diagram shows the common electrode and wiring in the components shown.

[0053] Figure 15 It means Figure 13 The diagram shows a plan view of the components that share only the electrodes. Detailed Implementation

[0054] The following is a reference to the appendix. Figure 1 Various embodiments of the present invention will be described below. Furthermore, the disclosure is merely an example, and those skilled in the art will readily conceive of appropriate modifications that maintain the spirit of the invention, which are of course included within the scope of the invention. Additionally, to make the description clearer, the drawings sometimes schematically represent the width, thickness, shape, etc., of various parts compared to the actual embodiment; however, this is merely an example and does not limit the interpretation of the invention. Furthermore, in this specification and the various drawings, elements that are the same as those already described in relation to the previously shown figures are labeled with the same reference numerals, and detailed descriptions are sometimes appropriately omitted.

[0055] The embodiments described in this specification are not general but rather embodiments that illustrate specific technical features of the same or corresponding invention. Hereinafter, with reference to the accompanying drawings... Figure 1 The display device of one embodiment will be described in detail below.

[0056] In this embodiment, the first direction X, the second direction Y, and the third direction Z are orthogonal to each other, but they may also intersect at an angle other than 90 degrees. The direction of the arrowhead pointing towards the third direction Z is defined as up or above, and the direction opposite to the direction of the arrowhead pointing towards the third direction Z is defined as down or below. Alternatively, the first direction X, the second direction Y, and the third direction Z may be referred to as the X direction, the Y direction, and the Z direction, respectively.

[0057] Furthermore, when designated as "the second component above the first component" and "the second component below the first component," the second component can be connected to the first component, or it can be located away from the first component. In the latter case, a third component can also be sandwiched between the first and second components. On the other hand, when designated as "the second component above the first component" and "the second component below the first component," the second component is connected to the first component.

[0058] Furthermore, assuming the observation position of the display device is at the front end of the arrow in the third direction Z, the view from this observation position toward the X-Y plane defined by the first direction X and the second direction Y is called a top view. The cross-section of the display device in the X-Z plane defined by the first direction X and the third direction Z, or the Y-Z plane defined by the second direction Y and the third direction Z, is called a cross-sectional view.

[0059] Figure 1 This is a diagram illustrating an example of the equivalent circuit of a display device.

[0060] The display device DSP has multiple pixels PX, multiple scan lines GL, and multiple signal lines SL in the display area DA of the displayed image. The multiple scan lines GL and multiple signal lines SL intersect each other. In addition, the display device DSP has drivers DR1 and DR2 outside the display area DA. The multiple scan lines GL are electrically connected to driver DR1. The multiple signal lines SL are electrically connected to driver DR2. Drivers DR1 and DR2 are controlled by a control unit.

[0061] The pixel PX referred to here is called a sub-pixel, color pixel, etc., such as a red pixel for displaying red, a green pixel for displaying green, a blue pixel for displaying blue, or a white pixel for displaying white. Pixel PX is located at the intersection of scan line GL and signal line SL. Furthermore, pixel PX is divided by two scan lines GL and two signal lines SL.

[0062] Each pixel PX has a switching element SW, a pixel electrode PE, and a common electrode CE opposite to the pixel electrode PE. The switching element SW is electrically connected to the scan line GL and the signal line SL. The pixel electrode PE is electrically connected to the switching element SW. That is, the pixel electrode PE is electrically connected to the signal line SL via the switching element SW. The common electrode CE is formed across multiple pixels PX. A common potential is applied to the common electrode CE.

[0063] Driver DR1 supplies scan signals to each scan line GL. Driver DR2 supplies image signals to each signal line SL. In the switching element SW, which is electrically connected to the scan line GL to which the scan signal is supplied, the signal line SL is turned on by the pixel electrode PE, and a voltage corresponding to the image signal supplied to the signal line SL is applied to the pixel electrode PE. The liquid crystal layer LC is driven by the electric field generated between the pixel electrode PE and the common electrode CE. More specifically, by the electric field generated between the pixel electrode PE and the common electrode CE, the orientation of the liquid crystal molecules in the liquid crystal layer LC changes from an initial orientation state in which no voltage is applied. Through this action, an image is displayed in the display area DA.

[0064] Figure 2 This is a cross-sectional view showing an example of the structure of a display device.

[0065] The display device DSP includes a substrate SUB1, a substrate SUB2, and a liquid crystal layer LC held between the substrates SUB1 and SUB2.

[0066] In addition to the switching element SW, pixel electrode PE, and common electrode CE, substrate SUB1 also includes a substrate BA1, an insulating layer INS, an insulating layer DIE, and an alignment film AL1. Furthermore, substrate SUB1 also includes... Figure 1 The scan line GL, signal line SL, driver DR1, and driver DR2 are shown. The substrate BA1 is formed of a transparent glass substrate or resin substrate. The substrate BA1 has a main surface S1A opposite to the substrate SUB2 and a main surface S1B opposite to the main surface S1A.

[0067] The switching element SW is formed on the main surface S1A side of the substrate BA1 and is covered by the insulating layer INS. Additionally, in Figure 2 In the example shown, for ease of explanation, the switching element SW is simplified, and the scan line GL and signal line SL are omitted. In reality, the insulating layer INS may also comprise multiple insulating layers. The switching element SW includes semiconductor layers or various electrodes formed within these layers.

[0068] The color filter CF is formed on the main surface S1A of the substrate BA1 and is covered by the insulating layer INS. The display device DSP in this embodiment has a COA (Colorfilter On Array) type configuration where the color filter CF is formed on the same substrate SUB1 (substrate) as the switching element SW. In this case, the color filter CF is formed between the switching element SW and the liquid crystal layer LC to ensure reliable color mixing suppression. Figure 2 In this configuration, the color filter CF is arranged overlapping the pixel electrode PE.

[0069] Pixel electrodes PE are formed on insulating layer INS and configured for each of multiple pixels PX. Pixel electrodes PE are covered by insulating layer DIE. Common electrodes CE are provided across multiple pixels PX. Common electrodes CE are formed on insulating layer DIE and are opposite to pixel electrodes PE across insulating layer DIE.

[0070] The pixel electrodes PE are electrically connected to the switching element SW via contact holes CH that penetrate the insulating layer INS. The pixel electrodes PE and the common electrode CE are, for example, transparent electrodes made of transparent conductive materials such as indium tin oxide (ITO) and indium zinc oxide (IZO).

[0071] The alignment film AL1 covers the common electrode and is in contact with the liquid crystal layer LC. The alignment film AL1 is, for example, a photoalignment film formed by applying a photoalignment process.

[0072] Substrate SUB2 includes substrate BA2 and alignment film AL2. Substrate BA2 is formed from a transparent glass substrate, resin substrate, or the like. Substrate BA2 has a main surface S2A opposite to substrate SUB1 and a main surface S2B opposite to main surface S2A.

[0073] Alignment film AL2 is disposed in contact with substrate BA2 and is also in contact with liquid crystal layer LC. Alignment film AL2 is the same as alignment film AL1, and is a photoalignment film that has undergone photoalignment treatment.

[0074] An insulating layer can also be provided between the alignment film AL2 and the substrate BA2, or a light-shielding layer can be provided opposite to the switching element SW.

[0075] Polarizing plate PL1 is bonded to the main surface S1B of substrate BA1, and polarizing plate PL2 is bonded to the main surface S2B of substrate BA2.

[0076] Figure 3 This is a cross-sectional view showing an example of the structure of substrate SUB1.

[0077] A thin-film transistor (TFT) is provided on the substrate BA1 as a switching element SW. The switching element SW is also called a transistor Tr.

[0078] The transistor Tr comprises a gate electrode BG, a semiconductor layer SC, an insulating layer GI, a drain electrode DE, an insulating layer PAS, and a gate electrode TG. Gate electrode BG and gate electrode TG are also referred to as the bottom gate and top gate, respectively. Alternatively, gate electrode BG and gate electrode TG are sometimes referred to as the first gate electrode and the second gate electrode, respectively. An insulating layer may also be disposed between the substrate BA1 and the gate electrode BG. Gate electrode BG also functions as a light-shielding layer for the semiconductor layer SC.

[0079] The gate electrode (BG) can be formed using a metallic material, such as a single-layer metal film or a stack of multiple metal films. Specific examples include molybdenum-tungsten alloy (MoW) films and stacked films made by sandwiching aluminum alloy films between titanium films.

[0080] An insulating layer GI1 is provided to cover the gate electrode BG and the substrate BA1. The insulating layer GI1 is formed, for example, a single layer of silicon oxide or silicon nitride, or a stack of silicon oxide and silicon nitride. As the insulating layer GI1, an oxygen-containing inorganic material such as silicon oxide is more preferred. The insulating layer GI may also have the function of blocking impurities from glass, etc.

[0081] The semiconductor layer SC is disposed on the gate electrode BG through the insulating layer GI1. The semiconductor layer SC is formed using oxide semiconductors such as IGZO (Indium Gallium Zinc Oxide), ITZO (Indium Tin Zinc Oxide), ZnON (ZincOxide Nitride), and IGO (Indium Gallium Oxide). However, the material of the semiconductor layer SC is not limited to these, and silicon can also be used.

[0082] An insulating layer GI2 is provided, which covers the semiconductor layer SC and the insulating layer GI1. The insulating layer GI2 is the same as the insulating layer GI1, and can be formed by a single layer of silicon oxide or silicon nitride or a stack of silicon oxide and silicon nitride.

[0083] On the insulating layer GI2, a gate electrode TG is disposed opposite to the semiconductor layer SC. The gate electrode TG can be formed using a metallic material, such as a single-layer metal film or a stack of multiple metal films. Specific examples include a molybdenum-tungsten alloy (MoW) film and a stack of films consisting of a titanium alloy film sandwiching an aluminum alloy film.

[0084] A semiconductor layer SC is provided between the gate electrode BG and the gate electrode TG. It can be said that the gate electrode TG is positioned opposite the gate electrode BG through the semiconductor layer SC. An insulating layer GI2 is provided between the gate electrode TG and the semiconductor layer SC, and an insulating layer GI1 is provided between the gate electrode BG and the semiconductor layer SC.

[0085] An insulating layer PAS is provided, covering the insulating layer GI2 and the gate electrode TG. The insulating layer PAS is formed, for example, by a single layer of silicon oxide or silicon nitride, or a stack of silicon oxide and silicon nitride.

[0086] A drain electrode DE is provided on the insulating layer PAS. The drain electrode DE contacts a portion of the semiconductor layer SC via a contact hole OP provided in the insulating layer PAS. When viewed from above, the drain electrode DE overlaps with the gate electrode TG and also overlaps with the pixel electrode PE. The drain electrode DE is formed of the aforementioned transparent conductive material such as ITO or IZO.

[0087] Although not illustrated, the signal line SL is formed on the same layer as the drain electrode DE. Like the drain electrode DE, the signal line SL contacts the rest of the semiconductor layer SC via contact holes provided in the insulating layer PAS.

[0088] An insulating layer ILI is provided, covering the insulating layer PAS and the drain electrode DE. The insulating layer ILI can be formed as a single layer of silicon oxide or silicon nitride, or as a stack of silicon oxide and silicon nitride.

[0089] A color filter CF is provided on the insulating layer ILI for each pixel PX. The color filter CF can be made of, for example, a transparent resin mixed with a coloring material. Figure 3 In this system, adjacent color filters (CFs) are formed in a way that results in different colors.

[0090] An insulating layer HRC is provided, covering the insulating layer ILI and the color filter CF. The insulating layer HRC is formed of an organic insulating material such as polyimide or acrylic resin. Contact holes CH are provided in the insulating layer HRC on the semiconductor layer SC and the gate electrode TG.

[0091] A pixel electrode PE is provided on the insulating layer HRC, covering the contact hole CH. The pixel electrode PE is connected to the drain electrode DE at the bottom of the contact hole CH. The pixel electrode PE can also be arranged overlapping with the color filter CF.

[0092] An insulating layer DIE is provided to cover the pixel electrode PE. The insulating layer DIE can be formed of a single layer of silicon oxide or silicon nitride, or a stack of silicon oxide and silicon nitride, but it is preferred to be formed of an insulating material with a high dielectric constant. Figure 3 In this process, the insulating layer DIE is formed from a single layer of silicon nitride film.

[0093] A common electrode CE is provided, covering an insulating layer DIE. As described above, the common electrode CE is provided across multiple pixels PX. Both the pixel electrode PE and the common electrode CE can be formed from transparent conductive materials such as ITO or IZO, as described above.

[0094] An insulating layer FL is provided on the common electrode CE to cover the contact hole CH. The insulating layer FL can be formed of any resin material.

[0095] Figure 4 This is a planar image representing one example of the pixels used in the comparison. Figure 4 To facilitate understanding of the accompanying drawings, only the wiring TM and the common electrode CE are shown. The wiring TM can be positioned above or below the common electrode CE. The wiring TM covers the signal line SL and the scan line GL. The wiring TM has the function of shielding the signal line SL and the scan line GL from light. If the scan line GL is designated as the first wiring and the signal line SL as the second wiring, the wiring TM is sometimes referred to as the third wiring.

[0096] The common electrode CE has multiple branches BR extending along a first direction X and a main stem ST extending along a second direction Y. The branches BR and the main stem ST are integrally formed and electrically connected to each other. In the illustrated example, the branches BR extend from the main stem ST toward the right side of the figure. The branches BR are, for example, shaped to taper towards the front end toward the right side of the figure (also called a "wedge shape"), and the width W1 connecting to the main stem ST is greater than the width W2 of the front end. Here, the width refers to the length along the second direction Y. In this embodiment, the length of the direction intersecting the extension direction of the electrode and wiring is referred to as the width.

[0097] exist Figure 2 In the case where the liquid crystal layer LC shown has positive dielectric anisotropy (positive type), the alignment processing direction AD of the alignment films AL1 and AL2 is parallel to the first direction X. That is, the alignment processing direction AD is parallel to the extension direction of the branch BR. Furthermore, the initial alignment direction of the liquid crystal molecules LM contained in the liquid crystal layer LC is parallel to the first direction X. Here, the liquid crystal layer LC is described as positive type.

[0098] In addition, Figure 2 In the case where the liquid crystal layer LC has negative dielectric anisotropy (negative type), the alignment processing directions of the alignment films AL1 and AL2 are parallel to the second direction Y. That is, the alignment processing direction in this case is orthogonal to the extension direction of the branch BR. Furthermore, the initial alignment direction of the liquid crystal molecules is parallel to the second direction Y.

[0099] If a voltage corresponding to the image signal is applied to the pixel electrode PE, an electric field is generated in the X-Y plane that intersects with the edges ED1 and EDB of the branch BR. The liquid crystal molecules LM rotate with their long axes approximately parallel to the electric field. For example, the liquid crystal molecules LM near edge ED1 rotate counterclockwise, and the liquid crystal molecules LM near edge ED2 rotate clockwise. That is, with respect to the branch BR, the rotation directions of the liquid crystal molecules LM are different on the edge ED1 side and the edge ED2 side.

[0100] If the display device's DSP becomes highly detailed, the area of ​​each pixel PX decreases. Therefore, the length of the branch BR in the first direction X also decreases. If it is desired to extend the length (width) of the branch BR in the first direction X of the pixel PX as a whole, there is a concern about continuity with the wiring TM.

[0101] If the length of the branch BR is shortened to prevent the branch BR from conducting with the wiring TM, the number of rotating liquid crystal molecules will decrease, which may reduce the brightness of the display device's DSP.

[0102] Figure 5 This is a plan view showing an example of pixels in this embodiment. Additionally... Figure 5 In order to make the accompanying drawings easier to understand, some of the constituent elements have been omitted.

[0103] Figure 5 The scan line GL shown extends along the first direction X. The length (width) of the scan line GL in the second direction Y is set to wg. The signal line SL, although not shown, extends along the second direction Y. The signal line SL is covered by the area TY of the wiring TM extending along the second direction Y.

[0104] The pixel electrode PE is disposed overlapping an area defined by two scan lines GL and two signal lines SL. However, the pixel electrode PE does not overlap equidistantly with the two scan lines GL. The area of ​​the pixel electrode PE overlapping with one scan line GL is larger than the area overlapping with the other scan line GL. The scan line GL adjacent to the front end of the branch BR of the common electrode CE is designated as scan line GL1. The scan line GL overlapping with the main branch ST of the common electrode CE is designated as scan line GL2. The area of ​​the pixel electrode PE overlapping with scan line GL1 is larger than the area of ​​the pixel electrode PE overlapping with scan line GL2. In other words, the length of the area of ​​the pixel electrode PE overlapping with scan line GL1 along the second direction Y is longer than the length of the area of ​​the pixel electrode PE overlapping with scan line GL2 along the second direction Y. That is, it can be said that the pixel electrode PE is located above the center of the distance between the two scan lines GL1 and GL2 (in the direction opposite to the second direction Y).

[0105] Figure 5 The main stem ST of the common electrode CE extends along the first direction X. Each branch BR of pixel PX extends from the main stem ST in a direction opposite to the second direction Y from the bottom to the top of the figure. The distance (interval) from the front end EC of branch BR to the edge ET of the adjacent wiring TM along the second direction Y in a pixel PX is set as gc.

[0106] The branch BR is positioned overlapping two adjacent pixels PX in the first direction X. Therefore, for example, the area to the right of one branch BR and the area to the left of another adjacent branch BR in the first direction X are arranged within one pixel PX. Alternatively, it can be said that half of each of the two adjacent branch BRs in the first direction X is opposite to each other.

[0107] The wiring TM has a region TX that overlaps with a portion of the scan line GL and extends along a first direction X, and a region TY that covers the signal line SL and extends along a second direction Y. The length (width) of the region TX extending along the first direction X in the second direction Y is defined as width wt. Furthermore, regions TX and TY are referred to as the first region and the second region, respectively. It can also be said that the length (width) of region TY along the first direction X is longer than the width of the signal line SL.

[0108] As described above, in this embodiment, the branch BR extends from the main branch ST from the lower side to the upper side of the figure. The length along the second direction Y of the region where the pixel electrode PE overlaps with the scan line GL1 is longer than the length along the second direction Y of the region where the pixel electrode PE overlaps with the scan line GL2. The width wt of the region TX extending along the first direction X of the wiring TM is shorter than the width wg of the scan line GL. In the pixel PX with this structure, a sufficient distance gc can be obtained. When the liquid crystal molecule LM oriented towards the leading edge EC of the branch BR is rotated by an electric field, a sufficient area can be obtained.

[0109] And through Figure 5 In the configuration shown, the common electrode CE and the wiring TM can be positioned sufficiently far apart. Therefore, the branch BR of the common electrode CE does not overlap with the wiring TM. Thus, short circuits between the common electrode CE and the wiring TM can be prevented.

[0110] Figure 6 It means Figure 5 The diagram shows a plan view of the components: the scan line GL, the signal line SL, and the drain electrode DE. The scan line GL extends along the first direction X. The signal line SL and the drain electrode DE extend along the second direction Y.

[0111] Figure 7 It means Figure 5The diagram shows a plan view of the components: scan line GL, signal line SL, drain electrode DE, and pixel electrode PE. The pixel electrode PE is disposed between two adjacent signal lines SL. The pixel electrode PE is disposed between two adjacent scan lines GL, overlapping with these two scan lines GL. As described above, in the two scan lines GL1 and GL2, the length pg1 of the region where the pixel electrode PE overlaps with scan line GL1 along the second direction Y is longer than the length pg2 of the region where the pixel electrode PE overlaps with scan line GL2 along the second direction Y.

[0112] Figure 8 It means Figure 5 The diagram shows the scan line GL, signal line SL, drain electrode DE, pixel electrode PE, and common electrode CE among the components shown. Figure 9 It means Figure 5 The diagram shows a plan view of the common electrode CE among the constituent elements. The main stem ST of the common electrode CE extends along the first direction X. That is, the main stem ST is arranged parallel to the scan line GL.

[0113] The branch BR of the common electrode CE extends from the main branch ST in a direction parallel to the second direction Y. That is, the branch BR is configured parallel to the signal line SL.

[0114] Define the boundary between the main branch ST and the branch BR as boundary DC, and define the hypotenuse of the branch BR as hypotenuse LP. Define the length along the second direction Y from boundary DC to the front end EC as length ht. Define the virtual point located at half the length from boundary DC to length ht as virtual point HP. Define the point where the virtual line from virtual point HP along the first direction X intersects hypotenuse LP as point HL. Alternatively, point HL can be described as the point located at half the length of hypotenuse LP.

[0115] In adjacent branches BR, the length (spacing) of adjacent points HL is defined as length pb. Length pb is preferably 0.2 μm to 4.5 μm, more preferably 0.5 μm to 2.5 μm. The angle formed by the hypotenuse LP relative to the second direction Y is defined as angle θ. Angle θ is preferably 2° to 45°, more preferably 5° to 15°. Figure 5 The distance gc shown is preferably between 1.0 μm and 1.5 μm. By taking such a length and angle, a display device DSP can be obtained that allows the liquid crystal molecules (LM) to rotate more easily, has a faster response speed, and higher brightness.

[0116] This embodiment describes a configuration in which the branch BR extends from the lower side of the drawing towards the upper side, but the invention is not limited thereto. The branch BR may also extend from the upper side of the drawing towards the lower side, that is, extend in both directions along the second direction Y.

[0117] This embodiment can suppress short circuits between the common electrode CE and the wiring TM, and fully obtain the area for the rotation of the liquid crystal molecules LM. Therefore, a display device with high reliability, fast response speed, and high brightness can be obtained.

[0118] <Example 1>

[0119] Figure 10 This is a plan view showing other configuration examples of the display device in the embodiment. Figure 10 The example shown is similar to Figure 5 Compared to the example shown, the difference is that one branch BR is set within one pixel PX. In this example, besides the fact that one branch BR is set within one pixel PX, the wiring TM also has a main trunk and branches.

[0120] exist Figure 10 In the configuration shown, the scan line GL, signal line SL, drain electrode DE, and pixel electrode PE are... Figure 7 The structures shown are the same.

[0121] Figure 11 It means Figure 10 The diagram shows the common electrode CE and wiring TM among the constituent elements. Figure 12 It only means Figure 10 A plan view of the common electrode CE among the constituent elements shown.

[0122] The common electrode CE has a main stem ST extending along the first direction X, a branch BR protruding from the main stem ST, and a straight section CY extending along the second direction Y and overlapping with the signal line SL. The straight section CY has a wiring shape and is provided across adjacent pixels PX along the second direction Y. The length (width) of the straight section CY along the first direction X is shorter than the length (width) of the signal line SL along the first direction X. In this configuration example, the branch BR is referred to as the first branch, and the main stem ST is referred to as the first main stem.

[0123] The main branch ST, the branch BR, and the straight section CY are formed as a single unit. As described above, one branch BR is provided within a region divided by two signal lines SL and two scan lines GL within one pixel PX.

[0124] The wiring TM has a main branch TT extending along the first direction X and a branch TR protruding from the main branch TT. The branch TR is identical to the branch BR, extending from the lower side to the upper side, i.e., in the opposite direction of the second direction Y. The branch TR, like the branch BR, has a tapering front end shape (wedge shape). The width of the branch TR, which overlaps with the boundaries of the branch TR and the main branch TT, is defined as width wt1, and the width of the front end TC of the branch TR is defined as width wt2. Width wt1 is longer than width wt2. Furthermore, in this configuration example, the branch TR is also referred to as the second branch, and the main branch TT is referred to as the second main branch.

[0125] By providing a branch TR with a tapered front end in a portion of the wiring TM, the electric field generated between the branch TR and the pixel electrode PE is formed obliquely relative to the first direction X or the second direction Y according to the wedge shape.

[0126] Furthermore, the branch section TR is arranged to overlap with the straight section CY of the common electrode CE when viewed from above. As described above, the straight section CY overlaps with the signal line SL, so it can be said that the signal line SL, the straight section CY, and the branch section TR are arranged to overlap.

[0127] A straight section CY with a common electrode CE is provided between the front end TC of the branch section TR and the main branch TT of the adjacent wiring TM in the second direction Y. The straight section CY can shield the voltage applied to the signal line SL. In addition, the distance between the front end TC of the wiring TM and the main branch TT is set as distance gc.

[0128] and Figure 9 Similar to the previous explanation, the length pb and angle θ are also calculated in this configuration example. In this configuration example, the length pb is defined as the length between points HL in the branch BR set within pixel PX. That is, the length pb is the width at a position where the height of the branch BR is half. The length pb is preferably 2.5 μm. The angle θ is preferably 5° to 15°. And the distance gc is preferably 1.0 μm to 1.5 μm. Furthermore, the length (width) of the straight section CY along the first direction X is defined as the length py. The length py is preferably 1.5 μm or more.

[0129] Furthermore, in this configuration example, the branch TR of the wiring TM and the branch BR of the common electrode CE do not overlap when viewed from above. In other words, the branches TR and BR are alternately arranged along the first direction X.

[0130] In this configuration example, the branch TR of the wiring TM is set to a tapered shape at the front end, but the shape of the branch TR is not limited to this. The length (width) of the branch TR along the first direction X can also be constant.

[0131] In this configuration example, a straight section CY is provided as part of the common electrode CE, but it is not limited to this. The straight section CY may also be part of the wiring TM. Furthermore, both the wiring TM and the common electrode CE may have straight sections. In this case, the wiring TM and the common electrode CE may also have the same shape.

[0132] In this example, the branch portions BR and TR are described as extending from the lower side of the drawing towards the upper side, but the present invention is not limited thereto. The branch portions BR and TR may also extend from the upper side of the drawing towards the lower side, that is, along the second direction Y.

[0133] This configuration example also achieves the same effect as the implementation method.

[0134] <Example 2>

[0135] Figure 13 This is a plan view illustrating other configuration examples of the display device according to the embodiment. Figure 13 In the example shown, with Figure 10 The difference between the example shown and the one depicted is that the two branches BR are set within one pixel PX.

[0136] exist Figure 13 In the configuration shown, the scan line GL, signal line SL, drain electrode DE, and pixel electrode PE are... Figure 7 The structures shown are the same.

[0137] Figure 14 It means Figure 13 The diagram shows the common electrode CE and wiring TM among the constituent elements. Figure 15 It only means Figure 13 A plan view of the common electrode CE among the constituent elements shown.

[0138] The common electrode CE has a main stem ST extending along a first direction X, a branch BR protruding from the main stem ST, and a protrusion CP extending along a second direction Y and overlapping a portion of the signal line SL. The main stem ST, the branch BR, and the protrusion CP are integrally formed.

[0139] The protrusion CP protrudes in the opposite direction to the extension of the branch BR. The edges of the main stem ST along the first direction X are designated as edges EDC1 and EDC2. One of the two adjacent main stems ST in the second direction Y is designated as main stem ST1, and the other as main stem ST2. The branch BR extends from edge EDC1 of main stem ST1 from the bottom to the top of the attached drawing. Conversely, the protrusion CP protrudes from edge EDC2 of main stem ST2 from the top to the bottom of the attached drawing.

[0140] Figure 13The shape of the wiring TM shown is similar to Figure 10 The wiring TM shown has the same shape. The branch TR of the wiring TM overlaps with the front end of the protrusion CP when viewed from above.

[0141] By providing a protrusion CP on the common electrode CE, the voltage applied to the signal line SL can be shielded. Additionally, the distance between the front end TC of the wiring TM and the main branch TT is set as distance gc.

[0142] and Figure 9 Similar to the previous description, the length pb and angle θ are also determined in this configuration example. In this configuration example, the length pb is the width at a position where half the height of the branch BR is located. The length pb is preferably 1.0 μm or more. The angle θ is preferably 5° or more and 15° or less. And the distance gc is preferably 1.0 μm or more and 1.5 μm or less. Furthermore, the length (width) of the protrusion CP along the first direction X is set as the length pd. The length pd is preferably 1.5 μm or more. In two adjacent branches BR provided within the pixel PX, the distance (interval) between point HL of one branch BR and point HL of the other branch BR is set as the distance pc. The distance pc is preferably 1.8 μm or more.

[0143] In this configuration example, the branch TR of the wiring TM is set to a tapered shape at the front end, but the shape of the branch TR is not limited to this. The length (width) of the branch TR along the first direction X can also be constant.

[0144] Furthermore, in this configuration example, the protrusion CP is designed with a tapered front end, but the shape of the protrusion CP is not limited to this. The length (width) of the protrusion CP along the first direction X can also be constant.

[0145] In this configuration example, a protrusion CP is provided as part of the common electrode CE, but it is not limited to this. The protrusion CP may also be part of the wiring TM. Furthermore, both the wiring TM and the common electrode CE may have protrusions. In this case, the wiring TM and the common electrode CE may also have the same shape.

[0146] In this example, the branch portions BR and TR are described as extending from the lower side to the upper side of the drawing, but the present invention is not limited thereto. The branch portions BR and TR may also extend from the upper side to the lower side of the drawing, that is, along the second direction Y.

[0147] In the above case, the protrusion CP extends from the lower side to the upper side of the figure, that is, it extends in the opposite direction of the second direction Y.

[0148] This configuration example also achieves the same effect as the implementation method.

[0149] Several embodiments of the present invention have been described, but these embodiments are given by way of example and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope or spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

Claims

1. A display device comprising: a plurality of scan lines extending in a first direction; a plurality of signal lines extending in a second direction intersecting the first direction; a plurality of pixels provided at intersections of the plurality of signal lines and the plurality of scan lines; a pixel electrode provided in a region divided by adjacent first and second scan lines of the plurality of scan lines and adjacent first and second signal lines of the plurality of signal lines; a common electrode having a stem portion and a plurality of branch portions; and a third wiring including a first region overlapping the plurality of scan lines and a second region overlapping the plurality of signal lines, a region in which the pixel electrode overlaps the first scan line is larger than a region in which the pixel electrode overlaps the second scan line, a width of the first region of the third wiring is shorter than a width of the scan line when a length in a direction intersecting a direction in which each of the third wiring and the scan line extends is set as the width, the plurality of branch portions of the common electrode extend from the stem portion in the second direction, a width at a boundary of each of the plurality of branch portions with the stem portion is longer than a width of a tip end of each of the plurality of branch portions when a length in a direction intersecting a direction in which each of the plurality of branch portions extends is set as the width.

2. The display device according to claim 1, wherein each of the plurality of branch portions overlaps two of the pixels adjacent in the first direction.

3. The display device according to claim 1, wherein a width of the second region of the third wiring is longer than a width of the signal line when a length in a direction intersecting a direction in which the signal line extends is set as the width.

4. The display device according to claim 1, wherein a length in the second direction in which the pixel electrode overlaps the first scan line is longer than a length in the second direction in which the pixel electrode overlaps the second scan line.

5. A display device comprising: a plurality of scan lines extending in a first direction; a plurality of signal lines extending in a second direction intersecting the first direction; a plurality of pixels provided at intersections of the plurality of signal lines and the plurality of scan lines; a pixel electrode provided in a region divided by adjacent first and second scan lines of the plurality of scan lines and adjacent first and second signal lines of the plurality of signal lines; a common electrode having a first stem portion, a plurality of first branch portions, and a straight portion; and a third wiring having a second stem portion and a plurality of second branch portions, a region in which the pixel electrode overlaps the first scan line is larger than a region in which the pixel electrode overlaps the second scan line, the first branch portions of the common electrode extend from the first stem portion in the second direction, the second branch portions of the third wiring extend from the second stem portion in the second direction, a width of the second stem portion of the third wiring is shorter than a width of the scan line, a width at a boundary of each of the plurality of first branch portions with the first stem portion is longer than a width of a tip end of each of the plurality of first branch portions.

6. The display device according to claim 5, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The plurality of first branch portions are respectively provided in each of the plurality of pixels.

7. The display device according to claim 5, The width of each of the plurality of second branch portions at the boundary with the second stem portion is longer than the width of the tip of each of the plurality of second branch portions.

8. The display device according to claim 5, The width of each of the plurality of second branch portions at the boundary with the second stem portion is constant.

9. The display device according to claim 5, The signal line, the straight portion, and the second branch portion overlap when viewed in plan.

10. The display device according to claim 5, The width of the straight portion is shorter than the width of the signal line.

11. The display device according to claim 5, Between the tip of the second branch portion of the third wiring and the second stem portion of the third wiring adjacent in the second direction, the straight portion of the common electrode is provided.

12. A display device comprising: a plurality of scan lines extending in a first direction; a plurality of signal lines extending in a second direction intersecting the first direction; a plurality of pixels provided at intersections of the plurality of signal lines and the plurality of scan lines; a pixel electrode provided in a region divided by adjacent first and second scan lines of the plurality of scan lines and adjacent first and second signal lines of the plurality of signal lines; a common electrode having a first stem portion, a plurality of first branch portions, and a protruding portion; and a third wiring having a second stem portion and a plurality of second branch portions, an area in which the pixel electrode overlaps the first scan line is larger than an area in which the pixel electrode overlaps the second scan line, the width of the second stem portion of the third wiring is shorter than the width of the scan line, the width of each of the plurality of first branch portions at the boundary with the first stem portion is longer than the width of the tip of each of the plurality of first branch portions, and the plurality of first branch portions respectively extend from the first stem portion in the second direction.

13. The display device according to claim 12, 2 of the first branch portions are provided in each of the plurality of pixels.

14. The display device according to claim 12, the width of each of the plurality of second branch portions at the boundary with the second stem portion is longer than the width of the tip of each of the plurality of second branch portions, and the plurality of second branch portions respectively extend from the second stem portion in the second direction.

15. The display device according to claim 12, the width of each of the plurality of second branch portions at the boundary with the second stem portion is constant.

16. The display device according to claim 12, the first branch portion extends from one of the two first stem portions adjacent in the second direction in a direction opposite to the second direction, and the protruding portion protrudes from the other of the two first stem portions adjacent in the second direction in the second direction.

17. The display device according to claim 12, the width of the protruding portion is shorter than the width of the signal line. ​

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