Liquid crystal display device

Abstract

The present invention can realize a pixel structure suitable for a liquid crystal display device capable of displaying a reflective mode and capable of being used as an in-cell touch panel. The liquid crystal display device of the present invention comprises: a first substrate; a second substrate disposed closer to the observer side than the first substrate; and a liquid crystal layer provided between the first substrate and the second substrate, the liquid crystal display device having a plurality of pixels arranged in a matrix. Each of the pixels includes a reflective region for display in a reflective mode. The first substrate has: thin film transistors provided corresponding to the pixels; a pixel electrode electrically connected to the thin film transistor; and a reflective layer on the opposite side from the liquid crystal layer with respect to the pixel electrode. The first substrate also has a plurality of touch sensor electrodes and a plurality of touch wires, each touch wire being electrically connected to a corresponding touch sensor electrode. The reflective layer is divided into a plurality of reflective segments electrically independent from each other, and each of the reflective segments overlaps two or more pixel electrodes in plan view.

Description

Technical Field

[0001] The present invention relates to a liquid crystal display device. Background Art

[0002] Liquid crystal display devices are generally divided into transmissive liquid crystal display devices and reflective liquid crystal display devices. Transmissive liquid crystal display devices display in a transmissive mode using light emitted from a backlight source. Reflective liquid crystal display devices display in a reflective mode using ambient light. In addition, a liquid crystal display device is proposed, which includes a reflective area in which each pixel displays in a reflective mode and a transmissive area in which each pixel displays in a transmissive mode. Such a liquid crystal display device is called a semi-transmissive (Transflective) or a transmissive-reflective dual-purpose liquid crystal display device.

[0003] Reflective and semi-transmissive liquid crystal display devices are preferably used as small and medium-sized display devices for mobile use, for example, outdoors. A reflective liquid crystal display device is disclosed, for example, in Patent Document 1. A semi-transmissive liquid crystal display device is disclosed, for example, in Patent Document 2. In addition, Patent Document 3 proposes a liquid crystal display device capable of improving the brightness of reflective display. In the reflective or semi-transmissive liquid crystal display device disclosed in Patent Document 3, the reflectivity is improved by a two-stage electrode structure in which a reflective electrode (reflective layer) and a transparent electrode (pixel electrode) are separated by an interlayer insulating layer.

[0004] In addition, a touch sensor function is provided to a liquid crystal display device used in a smartphone, a tablet computer, etc. As a type of touch sensor, various types such as a resistive film type, an electrostatic capacitance type, and an optical type are known.

[0005] Liquid crystal display devices with touch sensors (hereinafter referred to as "touch panels") are roughly divided into a method in which the touch sensor is mounted externally on the liquid crystal display device ("(On-cell) external type") and a method in which the touch sensor is built into the liquid crystal display device ("(In-cell) built-in type"). The built-in touch panel is more advantageous in terms of thinness and weight reduction than the external touch panel, and has the advantage of increased light transmittance.

[0006] There are two types of built-in touch panels: "On-cell" and "In-cell". Here, "cell" refers to the display panel. The display panel includes: an active matrix substrate (TFT substrate); an opposing substrate, which is arranged to be opposite to the TFT substrate; and a liquid crystal layer, which is arranged between the TFT substrate and the opposing substrate. In the "on-cell" type, the layer that performs the touch sensor function is arranged inside the display panel. In the "on-cell" type, the layer that performs the touch sensor function is arranged between the display panel and a polarizing plate arranged on the observer side of the display panel. Prior art literature Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2000-122094 Patent Document 2: Japanese Patent Application Publication No. 2003-131268 Patent Document 3: Japanese Patent Application Publication No. 2021-96461 Summary of the invention Technical Problems to be Solved by the Invention

[0008] In-cell type can realize the thinnest and lightest touch panel in principle. In addition, as already explained, liquid crystal display devices capable of displaying in a reflective mode are suitable for outdoor use. Therefore, although an embedded touch panel capable of displaying in a reflective mode is desired, it has not yet been realized.

[0009] The embodiments of the present invention have been made in view of the above-mentioned problems, and an object of the present invention is to realize a pixel structure suitable for a liquid crystal display device that can perform reflective mode display and can be used as an in-cell touch panel. Solutions to the problem

[0010] This specification discloses a display device described in the following items.

[0011] [Project 1] A liquid crystal display device comprising: a first substrate; A second substrate, which is arranged closer to the observer side than the first substrate; a liquid crystal layer disposed between the first substrate and the second substrate; a polarizing plate disposed closer to the observer than the liquid crystal layer; and a phase difference layer disposed between the polarizing plate and the liquid crystal layer, The liquid crystal display device has a plurality of pixels arranged in a matrix including a plurality of rows and a plurality of columns. Each of the plurality of pixels includes a reflective region for displaying in a reflective mode, and the first substrate has: A plurality of gate wirings extending in a row direction; a plurality of source wirings extending in a column direction; A plurality of thin film transistors, each of the plurality of thin film transistors being arranged corresponding to each of the plurality of pixels; a plurality of pixel electrodes, each of the plurality of pixel electrodes being electrically connected to a corresponding thin film transistor among the plurality of thin film transistors; and A reflective layer, which is formed of a conductive material and is located at least in the reflective region, and the reflective layer is located on a side opposite to the liquid crystal layer relative to the pixel electrode, and the first substrate further comprises: a plurality of touch sensor electrodes to which mutually different signals can be applied; and a plurality of touch wirings, each of the plurality of touch wirings being electrically connected to a corresponding touch sensor electrode among the plurality of touch sensor electrodes, The reflective layer is divided into a plurality of reflective segments which are electrically independent from each other. Each of the plurality of reflective segments overlaps with two or more pixel electrodes among the plurality of pixel electrodes in a plan view.

[0012] [Project 2] According to the liquid crystal display device of item 1, the two or more pixel electrodes overlapping each of the plurality of reflective segments are arranged in a plurality of rows and a plurality of columns.

[0013] [Item 3] In the liquid crystal display device according to item 1 or 2, the number of the plurality of reflective segments is equal to or greater than the number of the plurality of touch sensor electrodes.

[0014] [Item 4] According to the liquid crystal display device according to any one of items 1 to 3, mutually different voltages can be applied to the plurality of reflective segments.

[0015] [Item 5] According to the liquid crystal display device of item 4, each of the plurality of reflective segments is electrically connected to a corresponding touch sensor electrode among the plurality of touch sensor electrodes and a corresponding touch wiring among the plurality of touch wirings.

[0016] [Item 6] According to the liquid crystal display device described in item 5, each of the plurality of reflective segments is electrically connected to the corresponding touch sensor electrode via at least one first contact hole, and is electrically connected to the corresponding touch wiring via at least one second contact hole.

[0017] [Item 7] According to the liquid crystal display device of item 6, the at least one first contact hole is a plurality of first contact holes, and / or the at least one second contact hole is a plurality of second contact holes.

[0018] [Item 8] According to the liquid crystal display device of item 6 or 7, the at least one first contact hole is formed at a position different from the at least one second contact hole in a plan view.

[0019] [Item 9] According to the liquid crystal display device of item 8, any one of the at least one first contact hole and each of the at least one second contact hole are separated by more than one pixel in one or both of the row direction and the column direction.

[0020] [Item 10] According to the liquid crystal display device described in items 6 to 9, the at least one first contact hole is a plurality of first contact holes, and any one of the plurality of first contact holes is formed at a position different from that of the other first contact holes in a plan view.

[0021] [Item 11] According to the liquid crystal display device of item 10, any one of the plurality of first contact holes is separated from the other first contact holes by one pixel or more in one or both of the row direction and the column direction.

[0022] [Item 12] According to the liquid crystal display device described in items 6 to 11, the at least one second contact hole is a plurality of second contact holes, and any one of the plurality of second contact holes is formed at a position different from that of the other second contact holes when viewed from above.

[0023] [Item 13] According to the liquid crystal display device of item 12, any one of the plurality of second contact holes is separated from the other second contact holes by one pixel or more in one or both of the row direction and the column direction.

[0024] [Item 14] According to the liquid crystal display device described in items 6 to 13, at least one of the at least one first contact hole and the at least one second contact hole is located between pixel electrodes adjacent to each other among the plurality of pixel electrodes.

[0025] [Item 15] According to the liquid crystal display device according to any one of items 1 to 14, at least one touch wiring among the plurality of touch wirings overlaps a region between adjacent reflection segments among the plurality of reflection segments in a plan view.

[0026] [Item 16] According to the liquid crystal display device described in any one of items 1 to 15, the area between the touch sensor electrodes adjacent to each other among the plurality of touch sensor electrodes overlaps with the area between the pixel electrodes adjacent to each other among the plurality of pixel electrodes when viewed from above.

[0027] [Item 17] According to the liquid crystal display device described in any one of items 1 to 16, each of the multiple reflective segments, the area between the touch sensor electrodes adjacent to each other among the multiple touch sensor electrodes, and the area between the pixel electrodes adjacent to each other among the multiple pixel electrodes overlap when viewed from above.

[0028] [Item 18] According to the liquid crystal display device described in any one of items 1 to 17, the multiple touch wirings are adjacent to the lower surface of the reflective layer via a first insulating layer, and the multiple touch sensor electrodes or the multiple pixel electrodes are adjacent to the upper surface of the reflective layer via a second insulating layer.

[0029] [Item 19] According to the liquid crystal display device described in any one of items 1 to 18, each of the multiple touch wirings is configured between mutually adjacent gate wirings among the multiple gate wirings, or between mutually adjacent source wirings among the multiple source wirings.

[0030] [Item 20] According to the liquid crystal display device according to any one of items 1 to 19, the plurality of touch wirings are formed of the same conductive film as the plurality of gate wirings or the plurality of source wirings.

[0031] [Item 21] According to the liquid crystal display device described in any one of items 1 to 20, each of the multiple pixels includes a transmission area for displaying in a transmission mode, each of the multiple reflection segments has an opening portion, and the opening portion is formed in the transmission area, and the liquid crystal display device comprises: a light source and an additional polarizing plate, and the light source and the additional polarizing plate are arranged closer to the back side than the first substrate; and an additional phase difference layer, which is arranged between the additional polarizing plate and the liquid crystal layer.

[0032] [Item 22] According to the liquid crystal display device described in any one of items 1 to 21, the first substrate also has an insulating layer, which is formed in a manner of covering the multiple reflective segments, each of the multiple reflective segments has a concave-convex surface structure, and the thickness of the insulating layer is greater than the height difference of the concave-convex surface structure.

[0033] [Item 23] According to the liquid crystal display device of item 22, the thickness of the insulating layer is at least twice the height difference of the concave-convex surface structure.

[0034] [Item 24] According to the liquid crystal display device described in Item 22 or 23, the upper surface of the portion of the insulating layer that overlaps with the concave-convex surface structure of the multiple reflective segments has a concave-convex shape, and the height difference of the concave-convex shape of the insulating layer is less than 1 / 2 of the height difference of the concave-convex surface structure of the multiple reflective segments.

[0035] [Item 25] In the liquid crystal display device according to any one of items 1 to 24, the plurality of touch sensor electrodes are adjacent to the plurality of pixel electrodes via a dielectric layer, and at least one of the plurality of touch sensor electrodes and the plurality of pixel electrodes includes at least one slit.

[0036] [Item 26] According to the liquid crystal display device described in any one of items 1 to 25, the first substrate has a first horizontal orientation film in contact with the liquid crystal layer, the second substrate has a second horizontal orientation film in contact with the liquid crystal layer, when no voltage is applied, the liquid crystal layer exhibits a twisted orientation, and the twist angle of the liquid crystal layer when no voltage is applied is greater than 45° and less than 90°.

[0037] [Item 27] According to the liquid crystal display device of any one of items 1 to 26, substantially the same voltage can be applied to the plurality of reflective segments at substantially the same time.

[0038] [Item 28] The liquid crystal display device according to any one of items 1 to 26 is capable of applying substantially the same voltage to a group of pixel electrodes located in the same pixel row or the same pixel column among the multiple pixel electrodes and one or more reflective segments among the multiple reflective segments that overlap with the group of pixel electrodes when viewed from above, at substantially the same time.

[0039] [Item 29] In the liquid crystal display device according to any one of items 1 to 28, the reflective layer is located between the liquid crystal layer and the plurality of thin film transistors, and at least partially overlaps the plurality of thin film transistors when viewed from above. Effects of the Invention

[0040] According to the embodiment of the present invention, it is possible to realize a pixel structure suitable for a liquid crystal display device that can display a reflective mode and can be used as an in-cell touch panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a cross-sectional view schematically showing a liquid crystal display device 100 according to an embodiment of the present invention. Figure 22 is an equivalent circuit diagram of a plurality of pixels P included in the liquid crystal display device 100 . Figure 3 is a cross-sectional view schematically showing the liquid crystal display device 100 . Figure 4A 1 is a plan view schematically showing a backplane circuit BP of the TFT substrate 10 included in the liquid crystal display device 100 . Figure 4B 1 is a plan view schematically showing the first interlayer insulating layer 12 of the TFT substrate 10 . Figure 4C It is a plan view schematically showing the reflective layer 13 of the TFT substrate 10 . Figure 4D 1 is a plan view schematically showing the second interlayer insulating layer 14 of the TFT substrate 10 . Figure 4E 1 is a plan view schematically showing the pixel electrode PE of the TFT substrate 10 . Figure 4F 1 is a plan view schematically showing the dielectric layer 15 of the TFT substrate 10 . Figure 4G 1 is a plan view schematically showing the common electrode CE of the TFT substrate 10 . Figure 5 1 is a plan view illustrating the arrangement relationship between the reflective segments 13S and the touch wiring TL in the liquid crystal display device 100 . Figure 6 2 is a cross-sectional view schematically showing a liquid crystal display device 900 according to a comparative example. Figure 7 is a cross-sectional view schematically showing another liquid crystal display device 200 according to an embodiment of the present invention. Figure 8 is a cross-sectional view schematically showing another liquid crystal display device 300 according to an embodiment of the present invention. Fig. 9A 1 is a plan view schematically showing the common electrode CE of the TFT substrate 10 included in the liquid crystal display device 300 . Fig. 9B It is a plan view schematically showing the dielectric layer 15 of the TFT substrate 10 of the liquid crystal display device 300 . Fig. 9C 1 is a plan view schematically showing a pixel electrode PE of a TFT substrate 10 of a liquid crystal display device 300 . Fig.10 is a cross-sectional view schematically showing another liquid crystal display device 400 according to an embodiment of the present invention. Fig.11A 1 is a plan view showing an example of the upper electrode UE. Fig. 11B FIG. 1 is a plan view showing another example of the upper electrode UE. Fig. 11C It is a plan view showing still another example of the upper layer electrode UE. Fig.12 1 is a cross-sectional view showing an example of a preferred configuration of the reflective layer 13 having a stacked structure including a metal layer 13 a and a transparent conductive layer 13 b . Fig.13 1 is a cross-sectional view showing an example of a preferred configuration of the reflective layer 13 having a stacked structure including a metal layer 13 a and a transparent conductive layer 13 b . Fig.14 is a cross-sectional view schematically showing another liquid crystal display device 500 according to an embodiment of the present invention. Fig.15 1 is a diagram showing a reflective region Rf and a transmissive region Tr included in each pixel P of the liquid crystal display device 500 . DETAILED DESCRIPTION

[0042] The following describes an embodiment of the present invention with reference to the drawings. In addition, the embodiment of the present invention is not limited to the following exemplified contents.

[0043] [Implementation Method 1] Reference Figure 1 and Figure 2 A liquid crystal display device 100 according to this embodiment will be described. The liquid crystal display device 100 is a reflective liquid crystal display device that performs display in a normally black mode. Figure 1 is a cross-sectional view schematically showing the liquid crystal display device 100 . Figure 2 2 is an equivalent circuit diagram of a plurality of pixels P included in the liquid crystal display device 100 .

[0044] like Figure 1 As shown, the liquid crystal display device 100 includes an active matrix substrate (hereinafter referred to as a "TFT substrate") 10, an opposing substrate (sometimes also referred to as a "color filter substrate") 20 arranged closer to the observer side than the TFT substrate 10, and a liquid crystal layer 30 provided between the TFT substrate 10 and the opposing substrate 20. The liquid crystal display device 100 also includes a polarizing plate 40 arranged closer to the observer side than the liquid crystal layer 30, and a phase difference layer 50 arranged between the polarizing plate 40 and the liquid crystal layer 30. Here, the polarizing plate 40 is arranged closer to the observer side than the opposing substrate 20, and the phase difference layer 50 is arranged between the polarizing plate 40 and the opposing substrate 20. The polarizing plate 40 is specifically an absorption-type linear polarizing plate. In the example shown in the figure, the phase difference layer 50 includes a λ / 2 plate 51 and a λ / 4 plate 52.

[0045] In addition, if Figure 2As shown, the liquid crystal display device 100 has a plurality of pixels P. The plurality of pixels P are arranged in a matrix including a plurality of rows and a plurality of columns. The plurality of pixels P typically include a red pixel for displaying red, a green pixel for displaying green, and a blue pixel for displaying blue. As already described, the liquid crystal display device 100 is a reflective type. Therefore, each pixel P includes a reflective region Rf for displaying in a reflective mode.

[0046] The TFT substrate 10 includes a plurality of gate wirings (scanning wirings) GL, a plurality of source wirings (signal wirings) SL, a plurality of thin film transistors (TFTs) 11 , a plurality of pixel electrodes PE, and a common electrode CE.

[0047] A plurality of gate wirings GL extend in the row direction. Each gate wiring GL supplies a gate signal (scanning signal) to the corresponding TFT 11. A plurality of source wirings SL extend in the column direction intersecting (eg, substantially orthogonal to) the row direction. Each source wiring SL supplies a source signal (display signal) to the corresponding TFT 11.

[0048] A plurality of TFTs 11 are provided corresponding to each pixel P. The gate electrode and source electrode of each TFT 11 are electrically connected to the corresponding gate wiring GL and the corresponding source wiring SL, respectively. A plurality of pixel electrodes PE are electrically connected to the corresponding TFT 11 (more specifically, the drain electrode of the corresponding TFT 11).

[0049] The common electrode CE can generate a lateral electric field (fringe electric field) together with the pixel electrode PE in the liquid crystal layer 30. As described later, the common electrode CE is divided into a plurality of segments.

[0050] Next, refer to Figure 3 and FIG. 4A to FIG. 4G , a more specific structure of the TFT substrate 10 and the counter substrate 20 will be described. Figure 3 is a cross-sectional view schematically showing the liquid crystal display device 100 . FIG. 4A to FIG. 4G 1 is a plan view schematically showing each layer of the TFT substrate 10 .

[0051] The TFT substrate 10 includes a substrate 10 a , a TFT substrate 11 , a first interlayer insulating layer 12 , and a reflective layer 13 . The TFT substrate 10 also includes a second interlayer insulating layer 14 , a pixel electrode PE, a dielectric layer 15 , a common electrode CE, and a first horizontal alignment film 19 . FIG. 4A to FIG. 4G The backplane circuit BP including the TFT 11, the first interlayer insulating layer 12, the reflective layer 13, the second interlayer insulating layer 14, the pixel electrode PE, the dielectric layer 15, and the common electrode CE are shown respectively, and the area corresponding to the pixels P of 8 rows and 11 columns is shown.

[0052] The substrate 10a supports the TFT 11 and the like. The substrate 10a is transparent and has insulating properties. The substrate 10a is, for example, a glass substrate or a plastic substrate.

[0053] TFT11 is disposed on substrate 10a. TFT11 is disposed corresponding to a plurality of pixels P, respectively. TFT11 has a gate electrode GE, a gate insulating layer GI, a semiconductor layer SC, a source electrode SE, and a drain electrode DE. The gate electrode GE is electrically connected to a corresponding gate wiring GL, and the source electrode SE is electrically connected to a corresponding source wiring SL. The drain electrode DE is electrically connected to the pixel electrode PE. A circuit for driving a plurality of pixels P, including TFT11, gate wiring GL, and source wiring SL, is sometimes referred to as a backplane circuit BP. In addition, in Figure 3 In the figure, a TFT 11 with a bottom gate structure is illustrated, but the TFT 11 may be a top gate structure or a double gate structure.

[0054] The first interlayer insulating layer 12 is provided to cover the backplane circuit BP. The first interlayer insulating layer 12 may be a layer formed of an organic insulating material, for example, a photosensitive resin.

[0055] The reflective layer 13 is provided on the first interlayer insulating layer 12 in such a manner as to be located at least in the reflective region Rf. That is, the reflective layer 13 is arranged on the backplane circuit BP via the first interlayer insulating layer 12. In other words, the first interlayer insulating layer 12 is provided between the reflective layer 13 and the TFT 11. In further other words, the reflective layer 13 is adjacent to the TFT 11 via the first interlayer insulating layer 12.

[0056] The reflective layer 13 is formed of a conductive material that reflects light. More specifically, the reflective layer 13 is formed of a metal material with high reflectivity. As the material of the reflective layer 13, for example, a silver alloy, aluminum, or an aluminum alloy can be used.

[0057] The surface of the reflective layer 13 has a concavo-convex shape. That is, the reflective layer 13 has a concavo-convex surface structure. The concavo-convex surface structure of the reflective layer 13 is also called MRS (Micro Reflective Structure), which is provided to diffusely reflect ambient light to achieve a display close to paper white. The concavo-convex surface structure can be composed of a plurality of convex portions p randomly arranged in such a manner that the center interval between adjacent convex portions p is 5 μm or more and 50 μm or less, preferably 10 μm or more and 20 μm or less. When observed from the normal direction of the substrate 10a, the shape of the convex portion p is roughly circular or roughly polygonal. The area occupied by the convex portion p in the pixel P is, for example, about 20% to 40%. The height of the convex portion p is, for example, 1 μm or more and 5 μm or less.

[0058] There is no particular limitation on the method of forming the concavo-convex surface structure on the reflective layer 13. For example, as shown in the figure, by forming the first interlayer insulating layer 12 having the concavo-convex surface structure and forming the reflective layer 13 thereon, it is possible to give the surface of the reflective layer 13 a concavo-convex shape reflecting the concavo-convex surface structure of the first interlayer insulating layer 12. The first interlayer insulating layer 12 having the concavo-convex surface structure can be formed by the method disclosed in Japanese Patent No. 3394926, for example.

[0059] In addition, the reflective layer 13 is located between the liquid crystal layer 30 and the TFT 11. Furthermore, the reflective layer 13 at least partially overlaps with the TFT 11 when viewed from the normal direction of the display surface (ie, when viewed from above).

[0060] The second interlayer insulating layer 14 is provided on the first interlayer insulating layer 12 to cover the reflective layer 13. Therefore, it can be said that the reflective layer 13 is provided between the first interlayer insulating layer 12 and the second interlayer insulating layer 14. The second interlayer insulating layer 14 is a planarization layer formed of an organic insulating material, for example, a photosensitive resin.

[0061] The pixel electrode PE is respectively provided in a plurality of pixels P. In addition, the pixel electrode PE is provided on the second interlayer insulating layer 14. That is, the pixel electrode PE is adjacent to the upper surface of the reflective layer 13 via the second interlayer insulating layer 14. In other words, the second interlayer insulating layer 14 is provided between the pixel electrode PE and the reflective layer 13. In further other words, the reflective layer 13 is adjacent to the pixel electrode PE via the second interlayer insulating layer 14, and is located on the side opposite to the liquid crystal layer 30 relative to the pixel electrode PE (i.e., closer to the back side than the pixel electrode PE).

[0062] The pixel electrode PE is formed of a transparent conductive material. As the transparent conductive material, for example, indium tin oxide (ITO), indium zinc oxide (IZO (registered trademark)), or a mixture thereof can be used. The pixel electrode PE is electrically connected to the TFT 11 .

[0063] In the example shown in the figure, the pixel electrode PE is electrically connected to the drain electrode DE of the TFT 11 via the contact electrode 16. The contact electrode 16 can be formed of the same metal film as the reflective layer 13 (that is, the same layer as the reflective layer 13). A drain contact hole CHD is formed on the first interlayer insulating layer 12 to expose at least a portion of the drain electrode DE of the TFT 11, and the contact electrode 16 is connected to the drain electrode DE of the TFT 11 at the drain contact hole CHD. In addition, a pixel contact hole CHP is formed in the second interlayer insulating layer 14 to expose a portion of the contact electrode 16, and the pixel electrode PE is connected to the contact electrode 16 at the pixel contact hole CHP. In addition, an opening 130 is formed in a region of the reflective layer 13 that overlaps with the DR contact hole CHD and the pixel contact hole CHP.

[0064] In this way, the pixel electrode PE is connected to the TFT 11 via both the drain contact hole CHD and the pixel contact hole CHP. When viewed from above, the center of the drain contact hole CHD does not overlap with the center of the pixel contact hole CHP. In addition, here, when viewed from above, the drain contact hole CHD does not overlap with the pixel contact hole CHP.

[0065] The dielectric layer 15 is provided so as to cover the pixel electrode PE. The dielectric layer 15 can be formed of, for example, an inorganic insulating material.

[0066] The common electrode CE is provided on the dielectric layer 15. That is, the common electrode CE is adjacent to the pixel electrode PE via the dielectric layer 15. The common electrode CE is formed of a transparent conductive material. As the transparent conductive material for forming the common electrode CE, the same material as that of the pixel electrode PE can be used. Figure 3 as well as Figure 4G Although not shown in the figure, the common electrode CE includes a plurality of strip-shaped portions and at least one slit between two adjacent strip-shaped portions for each pixel P. By forming the slits in the common electrode CE, a fringe electric field (lateral electric field) is generated in the liquid crystal layer 30 according to the potential difference between the pixel electrode PE and the common electrode CE.

[0067] The first horizontal alignment film 19 is provided on the common electrode CE and is in contact with the liquid crystal layer 30. Therefore, it can be said that the pixel electrode PE and the common electrode CE are provided between the second interlayer insulating layer 14 and the first horizontal alignment film 19. In addition, it can be said that the dielectric layer 15 is also provided between the second interlayer insulating layer 14 and the first horizontal alignment film 19, and here, the pixel electrode PE is provided between the second interlayer insulating layer 14 and the dielectric layer 15, and the common electrode CE is provided between the dielectric layer 15 and the first horizontal alignment film 19.

[0068] The counter substrate 20 includes a substrate 20a, a color filter layer 21, and a second horizontal alignment film 29. Although not shown in the figure, the counter substrate 20 also includes a plurality of columnar spacers.

[0069] The substrate 20a supports the color filter layer 21 and the like. The substrate 20a is transparent and has insulating properties. The substrate 20a is, for example, a glass substrate or a plastic substrate.

[0070] The color filter layer 21 typically includes a red filter disposed in an area corresponding to a red pixel, a green filter disposed in an area corresponding to a green pixel, and a blue filter disposed in an area corresponding to a blue pixel. The red filter, the green filter, and the blue filter transmit red light, green light, and blue light, respectively.

[0071] In addition, when color display is not performed, the color filter layer 21 is omitted.

[0072] If necessary, an outer coating (planarization layer) covering the color filter layer 21 may also be provided. In addition, depending on the transparent conductive material (for the pixel electrode PE and the common electrode CE), the organic insulating material (for the first interlayer insulating layer 12 and the second interlayer insulating layer 14), the inorganic insulating material (for the dielectric layer 15), and the alignment film material (for the first horizontal alignment film 19 and the second horizontal alignment film 29) used, the white display may sometimes have a yellow tint. In this case, the chromaticity adjustment (blue shift) may be performed by forming an outer coating with a blue resist, so that the chromaticity of the white display is close to the chromaticity of the D65 light source, for example.

[0073] The columnar spacer defines the thickness (cell gap) of the liquid crystal layer 30. The columnar spacer is formed of a photosensitive resin.

[0074] The second horizontal alignment film 29 is disposed on the color filter layer 21 and contacts the liquid crystal layer 30 .

[0075] The liquid crystal layer 30 includes a nematic liquid crystal material having a positive dielectric anisotropy Δε or a nematic liquid crystal material having a negative dielectric anisotropy Δε. The dielectric anisotropy Δε is the dielectric constant ε of the liquid crystal molecule 31 in the long axis direction. / / and the dielectric constant ε in the short axis direction ⊥ The difference (i.e. ε / / -ε ⊥ ). The liquid crystal layer 30 may further contain a chiral agent as required. The liquid crystal layer 30 may be formed, for example, by a dropping method. The thickness of the liquid crystal layer 30 is not particularly limited.

[0076] The first horizontal alignment film 19 and the second horizontal alignment film 29 are each subjected to an alignment treatment to define the alignment direction of the liquid crystal molecules 31 included in the liquid crystal layer 30. The alignment direction defined by the first horizontal alignment film 19 and the alignment direction defined by the second horizontal alignment film 29 are different from each other.

[0077] Since the first horizontal alignment film 19 and the second horizontal alignment film 29 are provided on both sides of the liquid crystal layer 30, the liquid crystal molecules 31 of the liquid crystal layer 30 are horizontally aligned (i.e., the pretilt angle is substantially 0°) at least when no voltage is applied to the liquid crystal layer 30. As described above, the alignment direction defined by the first horizontal alignment film 19 and the alignment direction defined by the second horizontal alignment film 29 are different. Figure 3 As shown, the liquid crystal layer 30 is twisted when no voltage is applied. When a voltage is applied to the liquid crystal layer 30, that is, when a lateral electric field (fringe electric field) is generated in the liquid crystal layer 30 through the pixel electrode PE and the common electrode CE, the orientation state of the liquid crystal layer 30 changes according to the lateral electric field.

[0078] In the liquid crystal display device 100 of this embodiment, the common electrode CE is divided into a plurality of segments TX. The plurality of segments TX can apply different signals (voltages) to each other, and thus can function as "touch sensor electrodes" in the embedded touch panel. That is, the TFT substrate 10 of the liquid crystal display device 100 has a plurality of touch sensor electrodes TX. Each touch sensor electrode TX is provided corresponding to two or more pixels P.

[0079] In addition, the TFT substrate 10 further includes a plurality of touch wirings TL. The plurality of touch wirings TL are electrically connected to corresponding touch sensor electrodes TX among the plurality of touch sensor electrodes TX. Figure 4A As shown, the plurality of touch wirings TL extend in the column direction (the same direction as the source wirings SL), and each touch wiring TL is arranged between adjacent source wirings SL. In addition, here, the plurality of touch wirings TL are formed of the same conductive film as the plurality of source wirings SL (that is, the same layer as the plurality of source wirings SL). Therefore, the plurality of touch wirings TL are covered by the first interlayer insulating layer 12, and are adjacent to the lower surface of the reflective layer 13 via the first interlayer insulating layer 12.

[0080] The plurality of touch wirings TL are connected to a touch drive unit provided in a non-display area. The touch drive unit is configured, for example, to switch between a display mode in which the plurality of touch sensor electrodes TX function as a common electrode CE and a touch detection mode in which the plurality of touch sensor electrodes TX function in a time-sharing manner. For example, in the display mode, the touch drive unit applies a common signal to the touch sensor electrode TX (common electrode CE) via the touch wiring TL. On the other hand, in the touch detection mode, the touch drive unit applies a touch drive signal to the touch sensor electrode TX via the touch wiring TL.

[0081] In addition, in the liquid crystal display device 100 of this embodiment, the reflective layer 13 is divided into a plurality of reflective segments 13S that are electrically independent of each other. The plurality of reflective segments 13S overlap with two or more pixel electrodes PE among the plurality of pixel electrodes PE in a plan view. Here, the two or more pixel electrodes PE overlapping with each reflective segment 13S are arranged in multiple rows and columns. Figure 4C 2 shows an example in which 54 pixel electrodes PE arranged in 6 rows and 9 columns overlap each reflective segment 13S.

[0082] The number of the reflective segments 13S is greater than the number of the touch sensor electrodes TX. Here, the figure shows a case where the number of the reflective segments 13S is the same as the number of the touch sensor electrodes TX, but the number of the reflective segments 13S may be greater than the number of the touch sensor electrodes TX. That is, the reflective layer 13 may be divided finer than the common electrode CE.

[0083] Different voltages may be applied to the plurality of reflective segments 13S. Each reflective segment 13S is electrically connected to a corresponding touch sensor electrode TX among the plurality of touch sensor electrodes TX and a corresponding touch wiring TL among the plurality of touch wirings TL.

[0084] A plurality of first contact holes CH1 are formed across the second interlayer insulating layer 14 and the dielectric layer 15, and a plurality of second contact holes CH2 are formed in the first interlayer insulating layer 12. Each reflective segment 13S is electrically connected to the corresponding touch sensor electrode TX via at least one first contact hole CH1, and is electrically connected to the corresponding touch wiring TL via at least one second contact hole CH2. In the illustrated example, each reflective segment 13X is electrically connected to the corresponding touch sensor electrode TX via a plurality of (specifically three) first contact holes CH1, and is electrically connected to the corresponding touch wiring TL via a plurality of (specifically three) second contact holes CH2.

[0085] In this way, each reflective segment 13S is electrically connected to the corresponding touch sensor electrode TX and the corresponding touch wiring TL. In other words, the touch sensor electrode TX is electrically connected to the touch wiring TL via the reflective segment 13S.

[0086] As described above, in the liquid crystal display device 100 of this embodiment, the reflective layer 13 is divided into a plurality of reflective segments 13S that are electrically independent of each other. Therefore, compared with a case where the reflective layer 13 is not divided, the load of the touch sensor electrode TX (the parasitic capacitance formed by the touch sensor electrode TX and the reflective segment 13S) can be reduced.

[0087] In addition, in this embodiment, a configuration in which different voltages can be applied to the plurality of reflection segments 13S is illustrated, but the reflection segments 13S may not be electrically connected to other components but may be electrically floating (floating). As in this embodiment, if a configuration in which different voltages can be applied to the plurality of reflection segments 13S is adopted, the load on the touch sensor electrode TX can be further reduced. For example, as illustrated in this embodiment, if the reflection segment 13S is electrically connected to the touch sensor electrode TX, the reflection segment 13S will not become an electrical load on the touch sensor electrode TX, thereby increasing the degree of freedom in the wiring design of the touch sensor electrode TX.

[0088] If a structure in which each reflective segment 13S is electrically connected to the touch sensor electrode TX via at least one first contact hole CH1 and electrically connected to the touch wiring TL via at least one second contact hole CH2, compared with a structure in which the touch sensor electrode TX is directly connected to the touch wiring TL (a structure in which a contact hole is formed across the first interlayer insulating layer 12, the second interlayer insulating layer 14 and the dielectric layer 15), the flatness of the surface of the touch sensor electrode TX (common electrode CE) is improved, and the reduction in contrast ratio caused by the contact hole is suppressed.

[0089] The at least one first contact hole CH1 and the at least one second contact hole CH2 corresponding to each reflective segment 13S are formed at different positions from each other in a plan view, thereby improving the flatness of the surface of the touch sensor electrode TX and suppressing the reduction in contrast ratio caused by the contact holes. From the viewpoint of suppressing the reduction in contrast ratio, it is preferred that any one of the at least one first contact hole CH1 corresponding to each reflective segment 13S is separated from each of the at least one second contact hole CH2 by more than one pixel in one or both of the row direction and the column direction.

[0090] If the number of first contact holes CH1 for electrically connecting each reflective segment 13S to the touch sensor electrode TX is 2 or more, and / or the number of second contact holes CH2 for electrically connecting each reflective segment 13X to the touch wiring TL is 2 or more, the electrical connection between the reflective segment 13S and the touch sensor electrode TX and / or the electrical connection between the reflective segment 13S and the touch wiring TL can be made redundant. In addition, the resistivity of the touch wiring TL can be reduced and the touch sensitivity can be improved. In addition, the number of first contact holes CH1 and the number of second contact holes CH2 corresponding to each reflective segment 13S are not limited to the example shown in the figure (3 each).

[0091] In the case where there are multiple first contact holes CH1 corresponding to each reflective segment 13S, any one of the multiple first contact holes CH1 is preferably formed at a position different from other first contact holes CH1 in a plan view. In this way, the electrical connection between the reflective segment 13S and the touch sensor electrode TX can be made redundant, and the occurrence of sesame-like display unevenness can be suppressed. From the perspective of suppressing display unevenness, it is preferred that any one of the multiple first contact holes CH1 is separated from other first contact holes CH1 by more than one pixel in one or both directions of the row direction and the column direction.

[0092] In the case where there are multiple second contact holes CH2 corresponding to each reflective segment 13S, any one of the multiple second contact holes CH2 is preferably formed at a position different from other second contact holes CH2 when viewed from above. As a result, the electrical connection between the reflective segment 13S and the touch wiring TL can be made redundant, and the occurrence of sesame-like display unevenness can be suppressed. From the perspective of suppressing display unevenness, it is preferred that any one of the multiple second contact holes CH2 is separated from other second contact holes CH2 by more than one pixel in one or both directions of the row direction and the column direction.

[0093] When at least one of the at least one first contact hole CH1 and the at least one second contact hole CH2 corresponding to each reflective segment 13S is located between mutually adjacent pixel electrodes PE among the plurality of pixel electrodes PE, the reflectivity during white display can be improved.

[0094] It is preferable that at least one touch wiring TL among the plurality of touch wirings TL overlaps with a region between adjacent reflection segments 13S in a plan view. This can reduce the load on the touch wiring TL and improve touch sensitivity.

[0095] It is preferable that the region R1 (see Figure 3 , hereinafter sometimes referred to as the "first region") and a region R2 (refer to Figure 3 , hereinafter sometimes referred to as "second region") overlap in a plan view. Thus, the parasitic capacitance of the pixel electrode PE can be made uniform and the lattice-shaped display unevenness can be improved.

[0096] In addition, in the present embodiment, a plurality of touch wirings TL are adjacent to the lower surface of the reflective layer 13 via the first interlayer insulating layer 12, and a plurality of pixel electrodes PE are adjacent to the upper surface of the reflective layer 13 via the second interlayer insulating layer 14. Through such a configuration, the number of masks and processes required for the manufacture of the liquid crystal display device 100 can be reduced, thereby achieving cost reduction. For example, as illustrated, in the case where each touch wiring TL is arranged between mutually adjacent source wirings SL, by forming the touch wiring TL from the same conductive film as the source wiring SL, the number of masks and processes can be reduced. In addition, the touch wiring TL may extend in the row direction (the same direction as the gate wiring GL), and each touch wiring TL may be arranged between mutually adjacent gate wirings GL. In this case, by forming the touch wiring TL from the same conductive film as the gate wiring GL (i.e., the same layer as the gate wiring GL), the number of masks and processes can be reduced.

[0097] As described in this embodiment, when the reflective layer 13 (i.e., each reflective segment 13S) has a concavo-convex surface structure, it is preferable that the thickness of the second interlayer insulating layer 14 is larger than the height difference of the concavo-convex surface structure of each reflective segment 13S. If there is a concavo-convex shape reflecting the concavo-convex surface structure of the reflective segment 13S on the surface of the liquid crystal layer 30 side of the TFT substrate 10 (the interface between the TFT substrate 10 and the liquid crystal layer 30), the cell thickness (the thickness of the liquid crystal layer 30) becomes uneven, and there is a concern that the contrast ratio will be reduced. By making the thickness of the second interlayer insulating layer 14 larger than the height difference of the concavo-convex surface structure of the reflective segment 13S, the concavo-convex surface structure of the reflective segment 13S can be flattened by the second interlayer insulating layer 14, so that the concavo-convex surface structure of the reflective segment 13S is less likely to be reflected on the surface of the liquid crystal layer 30 side of the TFT substrate 10, and the reduction of the contrast ratio caused by the uneven cell thickness can be suppressed. In addition, it is also considered to use a light scattering sheet (for example, a light scattering sheet is arranged on the observer side of the opposing substrate 20) instead of forming a concave-convex surface structure in the reflection segment 13S, but according to the specifications of the light scattering sheet used even in this case, there is still concern about a reduction in contrast.

[0098] From the viewpoint of suppressing the decrease in contrast ratio caused by the non-uniformity of the cell thickness, the thickness of the second interlayer insulating layer 14 is preferably at least twice the height difference of the concave-convex surface structure. In addition, depending on the thickness of the second interlayer insulating layer 14, the concave-convex surface structure of the reflection segment 13S may not be completely flattened. In this case, the upper surface of the portion of the second interlayer insulating layer 14 that overlaps with the concave-convex surface structure of the reflection segment 13S has a concave-convex shape, but the height difference of the concave-convex shape is preferably less than 1 / 2 of the height difference of the concave-convex surface structure of the reflection segment 13S.

[0099] In addition, here, the configuration in which the common electrode CE is disposed above the pixel electrode PE is illustrated, but on the contrary, as described in Embodiment 3 described later, the pixel electrode PE may also be disposed above the common electrode CE. Hereinafter, the electrode located relatively above the pixel electrode PE and the common electrode CE is sometimes referred to as the "upper electrode", and the electrode located relatively below is sometimes referred to as the "lower electrode". The upper electrode and the lower electrode are adjacent to each other via the dielectric layer 15. In order to generate a lateral electric field, at least the upper electrode includes a plurality of strip-shaped portions and at least one slit located between two adjacent strip-shaped portions in each pixel P.

[0100] In addition, in the liquid crystal display device 100 of the present embodiment, the liquid crystal layer 30 is displayed in a transverse electric field mode in which a twisted orientation is exhibited when no voltage is applied. More specifically, the liquid crystal layer 30 is displayed in an FFS mode (referred to as a "TW-FFS mode") in which a twisted orientation is exhibited when no voltage is applied. Thus, compared with the case in which the liquid crystal layer 30 does not exhibit a twisted orientation when no voltage is applied (i.e., the twist angle of the liquid crystal layer 30 is 0°) and is displayed in a general FFS mode, the contrast ratio of the reflective display can be improved. From the viewpoint of improving the contrast ratio, the twist angle of the liquid crystal layer 30 when no voltage is applied is preferably greater than 45° and less than 90°.

[0101] Moreover, in this embodiment, the reflective layer 13 is located between the liquid crystal layer 30 and the TFT 11, and at least partially overlaps with the TFT 11 when viewed from above. By adopting such a structure, the reflective aperture ratio can be increased, and a brighter reflective display can be achieved. In addition, the TFT 11 can be protected from the influence of external light, and the reliability is improved.

[0102] As in the present embodiment, in the configuration in which the touch sensor electrode TX is electrically connected to the touch wiring TL via the reflective segment 13S, in the touch detection mode, substantially the same voltage (touch drive signal) may be applied to all the reflective segments 13S at substantially the same time. Alternatively, substantially the same voltage (touch drive signal) may be applied to a group of pixel electrodes PE located in the same pixel row or the same pixel column and one or more reflective segments 13S overlapping the group in a plan view at substantially the same time.

[0103] Figure 5 1 is a plan view illustrating the arrangement relationship between the reflective segments 13S and the touch wiring TL in the liquid crystal display device 100 .

[0104] like Figure 5 As shown, the liquid crystal display device 100 includes a display region DR and a non-display region FR. Figure 2 ) is used to define the display region DR. The non-display region FR is located at the periphery of the display region DR and is sometimes also referred to as a “peripheral region” or a “frame region”.

[0105] In the display region DR, the reflective layer 13 is divided into a plurality of reflective segments 13S. Each reflective segment 13S is electrically connected to a corresponding touch wiring TL.

[0106] The touch wiring TL is connected to a touch drive unit TD provided in the non-display region FR. The touch drive unit TD is configured to switch, for example, a display mode in which a plurality of touch sensor electrodes TX function as a common electrode CE and a touch detection mode in which the touch sensor electrodes TX function in a time-sharing manner. The touch drive unit TD applies a common signal to the reflective segment 13S via the touch wiring TL in the display mode. On the other hand, in the touch detection mode, the touch drive unit TD applies a touch drive signal to the reflective segment 13S via the touch wiring TL.

[0107] In addition, although not shown, in the non-display region FR, in addition to the touch drive unit TD, peripheral circuits including a gate driver for supplying a gate signal to the gate wiring GL, a source driver for supplying a source signal to the source wiring SL, and other drive circuits are also provided. These drive circuits may be mounted on the TFT substrate 10, or may be formed integrally (monolithically). A semiconductor chip including a part or all of the drive circuits may also be mounted in the non-display region FR.

[0108] Here, with Figure 6 The advantages of the liquid crystal display device 100 of the present embodiment are described by comparing it with the liquid crystal display device 900 of the comparative example shown in FIG. The liquid crystal display device 900 of the comparative example is a liquid crystal display device in which a transmissive in-cell touch panel is simply applied to a reflective liquid crystal display device with a two-segment electrode structure. In the following description, among the components of the liquid crystal display device 900 of the comparative example, the components having the same functions as the components of the liquid crystal display device 100 of the present embodiment are sometimes denoted by the same reference numerals, and their descriptions are omitted.

[0109] The liquid crystal display device 900 of the comparative example is different from the liquid crystal display device 100 of the present embodiment in that the touch wiring TL is provided on the second interlayer insulating layer 14. The touch wiring TL of the liquid crystal display device 900 is covered by a dielectric layer 17 different from the dielectric layer 15 located between the pixel electrode PE and the common electrode CE (touch sensor electrode TX), and the pixel electrode PE is provided on the dielectric layer 17. In addition, the touch wiring TL is connected to the touch sensor electrode TX at the contact hole CHT formed in the dielectric layers 15 and 17. In the liquid crystal display device 900 of the comparative example, the reflective layer 13 is not divided into a plurality of reflective segments that are electrically independent of each other.

[0110] In the liquid crystal display device 900 of the comparative example, the touch wiring TL is provided on the second interlayer insulating layer 14 and is located on the observer side of the reflective layer 13. Therefore, due to regular reflection based on the touch wiring TL, the glare of the reflective display becomes stronger, or the reflective aperture ratio may be reduced. Thus, in the liquid crystal display device 900 of the comparative example, the quality of the reflective display may be reduced.

[0111] In contrast, in the liquid crystal display device 100 of the present embodiment, the touch line TL is provided between the gate insulating layer GI and the first interlayer insulating layer 12 and is located on the back side of the reflective layer 13. Therefore, degradation of the quality of reflective display is suppressed.

[0112] In addition, in the liquid crystal display device 900 of the comparative example, there is a concern that the number of masks and processes required for manufacturing will increase significantly, thereby increasing costs. In the liquid crystal display device 900 of the comparative example, for example, it is necessary to deposit a conductive film for forming the touch wiring TL and pattern it, or to deposit a dielectric layer 17 and pattern it (to form an opening that becomes a part of the contact hole CHT).

[0113] In contrast, in the liquid crystal display device 100 of the present embodiment, since there is no dielectric layer corresponding to the dielectric layer 17 in the liquid crystal display device 900 of the comparative example, a mask and process for forming such a dielectric layer are not required. In addition, if the touch wiring TL is formed by the same conductive film as the source wiring SL, or the touch wiring TL is formed by the same conductive film as the gate wiring GL, it is not necessary to add a mask and process to form the touch wiring TL. Therefore, the number of masks and processes required for manufacturing can be reduced, and cost reduction can be achieved.

[0114] [Implementation Method 2] Reference Figure 7 , a liquid crystal display device 200 according to this embodiment is described. Figure 7 2 is a cross-sectional view schematically showing the liquid crystal display device 200. The following mainly describes the differences between the liquid crystal display device 200 of this embodiment and the liquid crystal display device 100 of Embodiment 1.

[0115] In the liquid crystal display device 100 of Embodiment 1, Figure 3 As shown, a region (first region) R1 between mutually adjacent touch sensor electrodes TX and a region R3 (hereinafter sometimes also referred to as a “third region”) between mutually adjacent reflective segments 13S overlap in a plan view.

[0116] In contrast, Figure 7 As shown, in the liquid crystal display device 200 of this embodiment, the first region R1 and the third region R3 are staggered when viewed from above. That is, each reflective segment 13S overlaps with the first region R1 when viewed from above. In the example shown in the figure, each reflective segment 13S and the first region R1 also overlap in the region (second region) R2 between the adjacent pixel electrodes PE when viewed from above. In this way, when the first region R1 and the third region R3 are staggered when viewed from above, the adverse effect of the electric field disorder in the first region R1 on the display can be reduced.

[0117] [Implementation method 3] Reference Figure 8 and 9A to 9C , describing the liquid crystal display device 300 of this embodiment. Figure 8 is a cross-sectional view schematically showing the liquid crystal display device 300 . 9A to 9C It is a plan view schematically showing the common electrode CE, the dielectric layer 15 , and the pixel electrode PE of the TFT substrate 10 included in the liquid crystal display device 300 . The backplane circuit BP, the first interlayer insulating layer 12, the reflective layer 13, and the second interlayer insulating layer 14 may be configured in the same manner as the liquid crystal display device 100 of Embodiment 1. Therefore, please refer to FIGS. Figure 4D .

[0118] In the liquid crystal display device 100 of the first embodiment, the common electrode CE is provided above the pixel electrode PE. Figure 8 As shown, the pixel electrode PE is disposed above the common electrode CE.

[0119] The common electrode CE is provided on the second interlayer insulating layer 14. Therefore, the plurality of touch sensor electrodes TX are adjacent to the upper surface of the reflective layer 13 via the second interlayer insulating layer 14. Each touch sensor electrode TX is connected to the corresponding reflective segment 13S at the first contact hole CH1 formed in the second interlayer insulating layer 14. The dielectric layer 15 is provided in a manner covering the common electrode CE, and the pixel electrode PE is provided on the dielectric layer 15. The pixel electrode PE is connected to the contact electrode 16 at the pixel contact hole CHP formed across both the dielectric layer 15 and the second interlayer insulating layer 14. An opening portion op is formed in a region of the common electrode CE that overlaps with the pixel contact hole CHP. In the present embodiment, the reflective layer 13 is located on the side opposite to the liquid crystal layer 30 (i.e., on the back side than the pixel electrode PE and the common electrode CE) with respect to the pixel electrode PE and the common electrode CE. In addition, it can be said that the pixel electrode PE and the common electrode CE are provided between the second interlayer insulating layer 14 and the first horizontal alignment film 19, or it can be said that the dielectric layer 15 is also provided between the second interlayer insulating layer 14 and the first horizontal alignment film 19. In the present embodiment, the common electrode CE is provided between the second interlayer insulating layer 14 and the dielectric layer 15 , and the pixel electrode PE is provided between the dielectric layer 15 and the first horizontal alignment film 19 .

[0120] also, Figure 8 as well as Fig. 9C Although not shown, the pixel electrode PE has a plurality of strip-shaped portions and at least one slit between two adjacent strip-shaped portions. By forming the slit in the pixel electrode PE, a fringe electric field is generated in the liquid crystal layer 30 according to the potential difference between the pixel electrode PE and the common electrode CE.

[0121] In the liquid crystal display device 300 of this embodiment, the reflective layer 13 is divided into a plurality of reflective segments 13S that are electrically independent of each other, similarly to the liquid crystal display device 100 of Embodiment 1. Therefore, the load on the touch sensor electrode TX (the parasitic capacitance formed by the touch sensor electrode TX and the reflective segment 13S) can be reduced.

[0122] As described above, in the configuration where the pixel electrode PE is provided above the common electrode CE, the slit is formed at least on the pixel electrode PE, and in the configuration where the common electrode CE is provided above the pixel electrode PE, the slit is formed at least in the common electrode CE.

[0123] In a relatively large liquid crystal display device (i.e., the area of ​​the pixel P is relatively large), it is preferred that the pixel electrode PE is arranged above the common electrode CE. In the configuration in which the pixel electrode PE is arranged above the common electrode CE, there is no need to form a slit in the common electrode CE, so the increase in the resistivity (surface resistivity) of the common electrode CE is suppressed compared to the configuration in which the common electrode CE is arranged above the pixel electrode PE. If the resistivity of the common electrode CE increases, the supply speed of the charge supplied to the common electrode CE decreases, and poor display conditions (such as flickering, shadows, etc.) are likely to occur due to the need to supply a large amount of charge to the common electrode CE (for example, images with biased pixel polarity, checkerboard patterns, striped patterns, or images in which a partial area of ​​the display is composed of these patterns).

[0124] In addition, in the structure in which the pixel electrode PE is arranged above the common electrode CE, it is necessary to form a slit in the pixel electrode PE, so the resistivity of the pixel electrode PE increases, but the area of ​​the pixel electrode PE is sufficiently smaller than that of the common electrode CE (for example, less than 1 millionth), so the amount of charge to be supplied is also small, and the charge is supplied from the TFT11 connected in units of pixels, so it is not easy to be affected by the displayed image and it is not easy to cause display defects.

[0125] In addition, in the configuration in which the pixel electrode PE is arranged above the common electrode CE, the pixel electrode PE in the area where the pixel contact hole CHP is formed cannot be provided with a slit for generating a fringe electric field, and thus the common electrode CE in this area needs to be provided with an opening portion op. Therefore, this area does not generate an effective fringe electric field, does not contribute to reflective display, and the reflectivity may decrease compared with the configuration in which the common electrode CE is arranged above the pixel electrode PE. Since the area of ​​the area that does not contribute to reflective display such as the contact hole does not depend on the size of the area of ​​the pixel P but requires a certain degree of area, the smaller the area of ​​the pixel P (i.e., high resolution), the higher the proportion of the area that does not contribute to reflective display in the pixel P, and the greater the reduction in the above reflectivity. Conversely, in a relatively large liquid crystal display device, it is easy to further reduce the proportion of the area that does not contribute to reflective display in the pixel P, so it is easy to suppress the reduction in the above reflectivity. For these reasons, in a relatively large liquid crystal display device (the area of ​​the pixel P is relatively large), it is advantageous to arrange the pixel electrode PE above the common electrode CE.

[0126] In addition, as described above, the smaller the area of ​​the pixel P (i.e., the higher the resolution), the higher the reduction in reflectivity caused by the fact that the area where the pixel contact hole CHP is formed does not contribute to the reflective display. Therefore, in a liquid crystal display device with a relatively high resolution (i.e., the area of ​​the pixel P is relatively small), the common electrode CE is preferably arranged above the pixel electrode PE.

[0127] [Implementation Method 4] Reference Fig.10 , describing a liquid crystal display device 400 of this embodiment. Fig.10 2 is a cross-sectional view schematically showing a liquid crystal display device 400. The following mainly describes the differences between the liquid crystal display device 400 of this embodiment and the liquid crystal display device 300 of Embodiment 3.

[0128] In the liquid crystal display device 300 of Embodiment 3, as Figure 8 As shown, a region (first region) R1 between mutually adjacent touch sensor electrodes TX and a region (third region) R3 between mutually adjacent reflective segments 13S overlap in a plan view.

[0129] In contrast, Fig.10 As shown, in the liquid crystal display device 400 of this embodiment, the first region R1 and the third region R3 are offset from each other in a plan view. That is, each reflective segment 13S overlaps with the first region R1 in a plan view. In the example shown in the figure, each reflective segment 13S and the first region R1 also overlap in the region (second region) R2 between adjacent pixel electrodes PE when viewed from above. In this way, when the first region R1 and the third region R3 are offset from each other in a plan view, the adverse effect of the electric field disorder in the first region R1 on the display can be reduced.

[0130] [Slits in upper electrode] As described above, at least the upper electrode of the pixel electrode PE and the common electrode CE includes at least one slit.

[0131] Fig.11A An example of an upper electrode UE is shown in FIG. Fig.11A The upper electrode UE shown in the figure includes a plurality of strip portions sp and a plurality of slits s1. In addition, of course, the number of the strip portions sp and the number of the slits s1 are not limited to Fig.11A Example shown.

[0132] Fig. 11B Another example of the upper electrode UE is shown in FIG. Fig. 11B The upper electrode UE shown in FIG. 11 includes a plurality of strip portions sp and a plurality of slits s1. Fig. 11B In the example shown, each strip-shaped portion sp includes a first portion spa extending in a certain direction (first direction) and a second portion spb extending in a direction different from the first direction (second direction). If the upper electrode UE has such a structure, two liquid crystal domains with different orientation directions (hereinafter referred to as "dual domain orientation") are formed in each pixel when a voltage is applied, so that color changes (displayed coloring) and grayscale changes accompanying changes in the viewing angle direction can be suppressed.

[0133] Fig. 11C Another example of the upper electrode UE is shown in FIG. Fig. 11C The upper electrode UE shown is Fig.11A and Fig. 11B The example shown also includes a plurality of strip-shaped portions sp and a plurality of slits sl. Fig. 11C In the example shown, the plurality of strip portions sp include at least one (four in this case) first strip portion sp1 extending in a certain direction (first direction) and at least one (four in this case) second strip portion sp2 extending in a direction (second direction) different from the first direction. By having such a configuration of the upper electrode UE, dual-domain orientation can also be achieved.

[0134] [Reflection layer] The reflective layer 13 may also have a laminated structure including a metal layer and a transparent conductive layer. Fig.12 An example of a preferred configuration when the reflective layer 13 has such a stacked structure will be described.

[0135] exist Fig.12 In the example shown, the reflective layer 13 includes a transparent conductive layer 13b formed of a transparent conductive material, and a metal layer 13a formed of a metal material and disposed on the transparent conductive layer 13b. The metal layer 13a has at least one opening 13ao, and the transparent conductive layer 13b is formed to include a portion overlapping the opening 13ao of the metal layer 13a.

[0136] The number of openings 13ao of the metal layer 13a is, for example, the same as the number of the first contact holes CH1, that is, formed corresponding to the first contact holes CH1. Fig.12 As shown, when viewed from the normal direction of the display surface, the first contact hole CH1 overlaps with the corresponding opening 13ao. That is, in the area where the common electrode CE is connected to the reflective layer 13, the metal material of the metal layer 13a is removed, and the common electrode 13 is connected to the transparent conductive layer 13b.

[0137] Near the first contact hole CH1, the cell thickness and fringe electric field are different from those in other areas, so the orientation disorder occurs. In particular, in the black display state, due to the influence of the orientation disorder, the light near the first contact hole CH1 is white (or gray), and the contrast ratio is reduced. Fig.12 As shown, by overlapping the first contact hole CH1 with the opening 13ao of the metal layer 13a, it is possible to suppress a decrease in contrast ratio due to alignment disorder near the first contact hole CH1.

[0138] In addition, Fig.12 In the stacked structure shown, the metal layer 13a is provided on the transparent conductive layer 13b, but it may also be provided as follows. Fig.13 As shown in FIG. 1 , a transparent conductive layer 13b is provided on the metal layer 13a. Fig.13 In the illustrated example, by overlapping the first contact hole CH1 with the opening 13ao of the metal layer 13a, it is possible to suppress a decrease in contrast ratio.

[0139] Fig.12 and Fig.13 2 shows an example in which the laminated reflective layer 13 is used in a configuration in which the common electrode CE is provided below the pixel electrode PE. However, of course, the laminated reflective layer 13 may also be used in a configuration in which the common electrode CE is provided above the pixel electrode PE.

[0140] [Oxide semiconductor TFT] As the TFT 11 provided in each pixel P, for example, an oxide semiconductor TFT can be preferably used (of course, it is not limited to this). In the oxide semiconductor TFT, an oxide semiconductor is used as a material for the active layer. That is, the oxide semiconductor TFT includes an oxide semiconductor layer as an active layer. In recent years, oxide semiconductors are materials that have attracted attention as active layer materials replacing amorphous silicon and polycrystalline silicon.

[0141] Oxide semiconductors have higher mobility than amorphous silicon. Therefore, oxide semiconductor TFTs can operate at higher speeds than amorphous silicon TFTs. In addition, oxide semiconductor films can be formed using a simpler process than polycrystalline silicon layers, so they can also be used in devices that require a large area.

[0142] In addition, the oxide semiconductor TFT has excellent off-leak characteristics, so it is also possible to use an operating mode that reduces the frequency of image rewriting for display. For example, when displaying a static image, the image data can be rewritten once per second. This driving method is called dormant driving or low-frequency driving, which can significantly reduce the power consumption of the liquid crystal display device.

[0143] By adopting pause driving and performing touch detection during a period when image rewriting is not being performed, it is possible to suppress a decrease in sensitivity of touch operation due to noise from the drive circuit, and to increase the S / N ratio (signal-to-noise ratio) by, for example, about 10 times that of the prior art.

[0144] In addition, oxide semiconductor TFTs are also advantageous in miniaturizing TFT size, so a configuration (called "MIP (Memory In Pixels)") in which a memory circuit is provided for each pixel P can also be preferably realized. The specific configuration of MIP is well known, and thus its description is omitted here.

[0145] The oxide semiconductor contained in the active layer (oxide semiconductor layer) of the oxide semiconductor TFT may be either an amorphous oxide semiconductor or a crystalline oxide semiconductor having a crystalline portion. Examples of crystalline oxide semiconductors include polycrystalline oxide semiconductors, microcrystalline oxide semiconductors, and crystalline oxide semiconductors whose c-axis is oriented substantially perpendicular to the layer.

[0146] The oxide semiconductor layer may have a stacked structure of more than two layers. The oxide semiconductor layer having a stacked structure may include an amorphous oxide semiconductor layer and a crystalline oxide semiconductor layer, or may include multiple crystalline oxide semiconductor layers having different crystal structures. In addition, the oxide semiconductor layer having a stacked structure may also include multiple amorphous oxide semiconductor layers. In the case where the oxide semiconductor layer has a two-layer structure including an upper layer and a lower layer, the energy gap of the oxide semiconductor contained in the lower layer may be different from the energy gap of the oxide semiconductor contained in the upper layer.

[0147] The materials, structures, film formation methods, and composition of oxide semiconductor layers having a stacked structure of amorphous oxide semiconductors and the above-mentioned crystalline oxide semiconductors are described in, for example, Japanese Patent Application Laid-Open No. 2014-007399. For reference, the entire disclosure of Japanese Patent Application Laid-Open No. 2014-007399 is cited in this specification.

[0148] The oxide semiconductor layer may contain, for example, at least one metal element selected from In, Ga, and Zn. In the present embodiment, the oxide semiconductor layer may contain, for example, an In-Ga-Zn-O semiconductor (e.g., indium gallium zinc oxide). Here, the In-Ga-Zn-O semiconductor is a ternary oxide of In (indium), Ga (gallium), and Zn (zinc), and the ratio (composition ratio) of In, Ga, and Zn is not particularly limited, and may include, for example, In:Ga:Zn=2:2:1, In:Ga:Zn=1:1:1, In:Ga:Zn=1:1:2, etc. Such an oxide semiconductor layer 11 can be formed by an oxide semiconductor film containing an In-Ga-Zn-O semiconductor.

[0149] In-Ga-Zn-O semiconductors may be amorphous or crystalline. As crystalline In-Ga-Zn-O semiconductors, preferably, those in which the c-axis is oriented substantially perpendicularly to the layer surface.

[0150] In addition, the crystal structure of the semiconductor of the crystalline In-Ga-Zn-O system is disclosed in, for example, the above-mentioned Japanese Patent Laid-Open No. 2014-007399, Japanese Patent Laid-Open No. 2012-134475, and Japanese Patent Laid-Open No. 2014-209727. For reference, the entire disclosure of Japanese Patent Laid-Open No. 2012-134475 and Japanese Patent Laid-Open No. 2014-209727 is cited in this specification. The TFT having the semiconductor layer of the In-Ga-Zn-O system has high mobility (more than 20 times compared with a-Si TFT) and low leakage current (less than one percent compared with a-Si TFT), and is therefore preferably used as a driving TFT (for example, a TFT present in a driving circuit, which is arranged in the periphery of a display area including a plurality of pixels and on the same substrate as the display area) and a pixel TFT (a TFT provided in a pixel).

[0151] The oxide semiconductor layer may also include other oxide semiconductors instead of the In-Ga-Zn-O semiconductor. For example, it may include an In-Sn-Zn-O semiconductor (e.g., In2O3-SnO2-ZnO; InSnZnO). The In-Sn-Zn-O semiconductor is a ternary oxide of In (indium), Sn (tin), and Zn (zinc). Alternatively, the oxide semiconductor layer 11 may also include In-Al-Zn-O series semiconductors, In-Al-Sn-Zn-O series semiconductors, Zn-O series semiconductors, In-Zn-O series semiconductors, Zn-Ti-O series semiconductors, Cd-Ge-O series semiconductors, Cd-Pb-O series semiconductors, CdO (cadmium oxide), Mg-Zn-O series semiconductors, In-Ga-Sn-O series semiconductors, In-Ga-O series semiconductors, Zr-In-Zn-O series semiconductors, Hf-In-Zn-O series semiconductors, Al-Ga-Zn-O series semiconductors, Ga-Zn-O series semiconductors, In-Ga-Zn-Sn-O series semiconductors, etc.

[0152] [Transflective type] In the above description, the reflective liquid crystal display devices 100, 200, 300, and 400 are exemplified, but the liquid crystal display device according to the embodiment of the present invention may also be a semi-transmissive liquid crystal display device. Fig.14 , describing the structure of a semi-transmissive liquid crystal display device 500.

[0153] The liquid crystal display device 500 is different from the liquid crystal display devices 100 , 200 , 300 and 400 in that the liquid crystal display device 500 includes an additional polarizing plate 40 ′, an additional phase difference layer 50 ′ and an illumination device (backlight source) 70 .

[0154] The polarizing plate 40 ′ is disposed on the back side of the liquid crystal layer 30 . More specifically, the polarizing plate 40 ′ is disposed on the back side of the TFT substrate 10 .

[0155] The phase difference layer 50' is disposed between the polarizing plate 40' and the liquid crystal layer 30. More specifically, the phase difference layer 50' is disposed between the polarizing plate 40' and the TFT substrate 10. The phase difference layer 50 may include, for example, a λ / 2 plate and a λ / 4 plate.

[0156] The lighting device 70 is arranged on the back side of the polarizing plate 40' (the back side of the TFT substrate 10). In the example shown in the figure, the lighting device 70 includes a light source (e.g., LED) 71 that emits light, a light guide plate 72 that guides the light from the light source 71 to the polarizing plate 40' side, and a reflective plate 73 arranged on the back side of the light guide plate 72. The lighting device 70 may further include a prism sheet and a diffusion sheet arranged on the front side (or back side) of the light guide plate 72.

[0157] like Fig.15 As shown, each pixel P of the liquid crystal display device 500 includes a reflective region Rf for displaying in a reflective mode and a transmissive region Tr for displaying in a transmissive mode. The reflective layer 13 (each reflective segment 13S) of the TFT substrate 10 has an opening 13o formed in the transmissive region Tr. The proportion of the area of ​​the transmissive region Tr in the pixel P can be appropriately set according to the purpose, for example, to be greater than 20% and less than 90%. In addition, the position and shape of the transmissive region Tr in the pixel P can also be appropriately set according to the purpose, for example. Industrial applicability

[0158] According to the embodiment of the present invention, a pixel structure suitable for a liquid crystal display device capable of displaying a reflective mode and being used as an in-cell touch panel can be realized. The embodiment of the present invention is applicable to reflective and semi-transmissive liquid crystal display devices. Description of Reference Numerals

[0159] 10Active matrix substrate (TFT substrate) 10a, 20a substrate 11Thin Film Transistor (TFT) 12First interlayer insulation layer 13Reflection layer 13o opening 13a Metal layer 13ao Opening of metal layer 13b Transparent conductive layer 13X Reflection Segment 14 Second interlayer insulation layer 15 Dielectric layer 16 contact electrodes 19 first horizontal alignment film 20 Counter substrate (color filter substrate) 21 Color filter layers 29 second horizontal alignment film 30 Liquid crystal layer 31 liquid crystal molecules 40 polarizing plate 40' Extra Polarizer Plate 50 Phase difference layer 50' additional phase difference layer 51 λ / 2 plate 52 λ / 4 plate 70 lighting device (backlight source) 71 Light Source 72 Light guide plate 73 Reflector 100, 200, 300, 400, 500 LCD display device P Pixel PE pixel electrode CE common electrode UE upper electrode GL Gate wiring SL Source Routing BP Backplane Circuit CH1 first contact hole CH2 Second contact hole CHD drain contact hole CHP pixel contact hole sp Strip portion of the upper electrode First part of the spa strip spb Second part of the strip sp1 first band sp2 Second band sl Slit of upper electrode DR Display Area FR non-display area TL touch wiring TX touch sensor electrodes TD touch driver Rf reflection area Tr transmission area

Claims

1. A liquid crystal display device, comprising: a first substrate; A second substrate, which is arranged closer to the observer side than the first substrate; a liquid crystal layer disposed between the first substrate and the second substrate; a polarizing plate disposed closer to the observer than the liquid crystal layer; as well as a phase difference layer disposed between the polarizing plate and the liquid crystal layer, The liquid crystal display device has a plurality of pixels arranged in a matrix including a plurality of rows and a plurality of columns. The liquid crystal display device is characterized in that Each of the plurality of pixels includes a reflective area for displaying in a reflective mode, The first substrate has: A plurality of gate wirings extending in a row direction; a plurality of source wirings extending in a column direction; A plurality of thin film transistors, each of the plurality of thin film transistors being arranged corresponding to each of the plurality of pixels; A plurality of pixel electrodes, each of the plurality of pixel electrodes being electrically connected to a corresponding thin film transistor among the plurality of thin film transistors; as well as a reflective layer, which is formed of a conductive material and is located at least in the reflective region, and the reflective layer is located on a side opposite to the liquid crystal layer relative to the pixel electrode, The first substrate further comprises: a plurality of touch sensor electrodes to which mutually different signals can be applied; as well as a plurality of touch wirings, each of the plurality of touch wirings being electrically connected to a corresponding touch sensor electrode among the plurality of touch sensor electrodes, The reflective layer is divided into a plurality of reflective segments which are electrically independent from each other. Each of the plurality of reflective segments overlaps with two or more pixel electrodes among the plurality of pixel electrodes in a plan view.

2. The liquid crystal display device according to claim 1, wherein: The two or more pixel electrodes overlapping each of the plurality of reflective segments are arranged in a plurality of rows and a plurality of columns.

3. The liquid crystal display device according to claim 1 or 2, characterized in that: The number of the plurality of reflective segments is greater than the number of the plurality of touch sensor electrodes.

4. The liquid crystal display device according to claim 1 or 2, characterized in that: Different voltages can be applied to the plurality of reflective segments.

5. The liquid crystal display device according to claim 4, characterized in that: Each of the plurality of reflective segments is electrically connected to a corresponding touch sensor electrode among the plurality of touch sensor electrodes and a corresponding touch wiring among the plurality of touch wirings.

6. The liquid crystal display device according to claim 5, characterized in that: Each of the plurality of reflective segments is electrically connected to the corresponding touch sensor electrode via at least one first contact hole, and is electrically connected to the corresponding touch wiring via at least one second contact hole.

7. The liquid crystal display device according to claim 6, characterized in that: The at least one first contact hole is a plurality of first contact holes, and / or the at least one second contact hole is a plurality of second contact holes.

8. The liquid crystal display device according to claim 6, characterized in that: The at least one first contact hole is formed at a position different from the at least one second contact hole in a plan view.

9. The liquid crystal display device according to claim 8, characterized in that: Any one of the at least one first contact hole and each of the at least one second contact hole are separated by more than one pixel in one or both of a row direction and a column direction.

10. The liquid crystal display device according to claim 6, characterized in that: The at least one first contact hole is a plurality of first contact holes, and any one of the plurality of first contact holes is formed at a position different from that of the other first contact holes in a plan view.

11. The liquid crystal display device according to claim 10, characterized in that: Any one of the plurality of first contact holes is separated from the other first contact holes by more than one pixel in one or both of the row direction and the column direction.

12. The liquid crystal display device according to claim 6, characterized in that: The at least one second contact hole is a plurality of second contact holes, and any one of the plurality of second contact holes is formed at a position different from that of the other second contact holes in a plan view.

13. The liquid crystal display device according to claim 12, characterized in that: Any one of the plurality of second contact holes is separated from the other second contact holes by more than one pixel in one or both of the row direction and the column direction.

14. The liquid crystal display device according to claim 6, characterized in that: At least one of the at least one first contact hole and the at least one second contact hole is located between pixel electrodes adjacent to each other among the plurality of pixel electrodes.

15. The liquid crystal display device according to claim 1 or 2, characterized in that: At least one touch wiring among the plurality of touch wirings overlaps a region between mutually adjacent reflective segments among the plurality of reflective segments in a plan view.

16. The liquid crystal display device according to claim 1 or 2, characterized in that: A region between mutually adjacent touch sensor electrodes among the plurality of touch sensor electrodes overlaps with a region between mutually adjacent pixel electrodes among the plurality of pixel electrodes in a plan view.

17. The liquid crystal display device according to claim 1 or 2, characterized in that: Each of the plurality of reflective segments, a region between mutually adjacent touch sensor electrodes among the plurality of touch sensor electrodes, and a region between mutually adjacent pixel electrodes among the plurality of pixel electrodes overlap in a plan view.

18. The liquid crystal display device according to claim 1 or 2, characterized in that: The plurality of touch wirings are adjacent to the lower surface of the reflective layer via the first insulating layer. The plurality of touch sensor electrodes or the plurality of pixel electrodes are adjacent to an upper surface of the reflective layer via a second insulating layer.

19. The liquid crystal display device according to claim 1 or 2, characterized in that: Each of the plurality of touch wirings is arranged between mutually adjacent gate wirings among the plurality of gate wirings, or between mutually adjacent source wirings among the plurality of source wirings.

20. The liquid crystal display device according to claim 1 or 2, characterized in that: The plurality of touch wirings are formed of a same conductive film as the plurality of gate wirings or the plurality of source wirings.

21. The liquid crystal display device according to claim 1 or 2, characterized in that: Each of the plurality of pixels includes a transmissive region for displaying in a transmissive mode, Each of the plurality of reflection segments has an opening, and the opening is formed in the transmission area. The liquid crystal display device comprises: a light source and an additional polarizing plate, wherein the light source and the additional polarizing plate are arranged closer to the back side than the first substrate; and The additional phase difference layer is arranged between the additional polarizing plate and the liquid crystal layer.

22. The liquid crystal display device according to claim 1 or 2, characterized in that: The first substrate further has an insulating layer, and the insulating layer is formed in a manner of covering the plurality of reflection segments. Each of the plurality of reflection segments has a concave-convex surface structure, The thickness of the insulating layer is greater than the height difference of the concave-convex surface structure.

23. The liquid crystal display device according to claim 22, characterized in that: The thickness of the insulating layer is more than twice the height difference of the concave-convex surface structure.

24. The liquid crystal display device according to claim 22, characterized in that: The upper surface of a portion of the insulating layer overlapping with the concavo-convex surface structure of the plurality of reflection segments has a concavo-convex shape, The height difference of the concavo-convex shape of the insulating layer is less than 1 / 2 of the height difference of the concavo-convex surface structure of the plurality of reflection segments.

25. The liquid crystal display device according to claim 1 or 2, characterized in that: The plurality of touch sensor electrodes are adjacent to the plurality of pixel electrodes via a dielectric layer. At least one of the plurality of touch sensor electrodes and the plurality of pixel electrodes includes at least one slit.

26. The liquid crystal display device according to claim 1 or 2, characterized in that: The first substrate has a first horizontal alignment film in contact with the liquid crystal layer. The second substrate has a second horizontal alignment film in contact with the liquid crystal layer. When no voltage is applied, the liquid crystal layer exhibits a twisted orientation. The twist angle of the liquid crystal layer when no voltage is applied is greater than or equal to 45° and less than or equal to 90°.

27. The liquid crystal display device according to claim 1 or 2, characterized in that: The plurality of reflective segments can be applied with substantially the same voltage at substantially the same time.

28. The liquid crystal display device according to claim 1 or 2, characterized in that: It is possible to apply substantially the same voltage at substantially the same time to a group of pixel electrodes located in the same pixel row or the same pixel column among the multiple pixel electrodes and one or more reflective segments among the multiple reflective segments that overlap with the group of pixel electrodes when viewed from above.

29. The liquid crystal display device according to claim 1 or 2, characterized in that: The reflective layer is located between the liquid crystal layer and the plurality of thin film transistors, and at least partially overlaps the plurality of thin film transistors when viewed from above.

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