Touch sensors, display devices

Abstract

A touch sensor (10) comprises a first electric conductor (F1) having a net-like wiring, and a second electric conductor (F2) adjoining the first electric conductor and having a net-like wiring. At least a portion of the boundary (BS) between the first and second electric conductors extends in a first direction (direction D1), and the net-like wiring of the first electric conductor includes a plurality of broken-wire points K which are formed such that broken-wire edges (ED) intersect the first direction D1 in a plan view.

Description

[Technical Field]

[0001] The present invention relates to a touch sensor and a display device. [Background technology]

[0002] Patent Document 1 discloses the structure of a touch sensor using a metal mesh. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2018-152122 Summary of the Invention [Problem to be solved by the invention]

[0004] When applied to a display panel, display unevenness caused by the touch sensor may be visible. [Means for solving the problem]

[0005] The touch sensor disclosed herein comprises a first conductor having mesh wiring and a second conductor adjacent to the first conductor and also having mesh wiring, wherein at least a portion of the boundary between the first conductor and the second conductor extends in a first direction, and the mesh wiring of the first conductor includes a plurality of breaks formed such that the break edges intersect with the first direction in a planar view. [Effects of the Invention]

[0006] According to one aspect of the present disclosure, when applied to a display panel, display unevenness caused by a touch sensor is reduced. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a plan view illustrating a configuration of a touch sensor according to a first embodiment. [Figure 2]2 is an enlarged plan view showing the configuration of the area surrounded by the white line in FIG. 1. FIG. [Figure 3] 3 is a plan view showing the configuration of the disconnection portion in FIG. 2. FIG. [Figure 4] FIG. 2 is a schematic diagram illustrating a configuration of a touch sensor. [Figure 5] 1 is a schematic cross-sectional view illustrating the operating principle of a touch sensor. [Figure 6] FIG. 2 is a cross-sectional view showing the configuration of a touch sensor. [Figure 7] FIG. 2 is a cross-sectional view showing the configuration of a touch sensor. [Figure 8] FIG. 2 is a plan view illustrating a configuration of a touch sensor. [Figure 9] 1 is a schematic cross-sectional view showing a configuration of a display device according to an embodiment of the present invention. [Figure 10] 1 is a plan view showing a configuration of a display device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] FIG. 1 is a plan view showing the configuration of a touch sensor according to a first embodiment. FIG. 2 is an enlarged plan view showing the configuration of the area enclosed by the white line in FIG. 1. FIG. 3 is a plan view showing the configuration of a disconnection location in FIG. 2. As shown in FIGS. 1 to 3, the touch sensor 10 includes a first conductor F1 having a mesh wiring (e.g., a metal mesh) W1 and a second conductor F2 adjacent to the first conductor F1 and having a mesh wiring W2. At least a portion of a boundary BS between the first conductor F1 and the second conductor F2 extends in a first direction D1. The mesh wiring W1 of the first conductor F1 includes multiple disconnection locations K formed such that disconnection edges ED intersect with the first direction D1 in a plan view. The second direction D2 is a direction perpendicular to the first direction D1. The plan view is, for example, from a line of sight parallel to the thickness direction of the touch sensor 10, and includes perspective viewing.

[0009] The second conductor F2 is electrically insulated from the first conductor F1, and the mesh wiring W2 of the second conductor F2 includes a plurality of disconnection points K formed so that disconnection edges ED intersect with the first direction D1 in a plan view. The disconnection edges ED may be formed so as to be substantially perpendicular to the first direction D1, and the mesh wiring W1-W2 is optically reflective.

[0010] In a configuration in which the boundaries BS extend in the first direction D1 and the mesh wiring does not have any breaks K, the light reflectance becomes directional, i.e., the light incident on the first and second conductors F1 and F2 in the first direction D1 has a lower reflectance than the light incident on the first and second conductors F1 and F2 in the second direction D2.

[0011] 1 to 3, the disconnection edge ED includes a plurality of disconnection locations K that are formed so as to intersect with the first direction D1 in a plan view, and therefore the reflectance of light incident on the first and second conductors F1 and F2 in the second direction D2 can be reduced compared to a configuration without the disconnection locations K. This reduces the directivity of the light reflectance, and can improve the display quality (e.g., display unevenness) of a display panel that includes the touch sensor 10.

[0012] 4 is a schematic diagram showing the configuration of a touch sensor. The touch sensor 10 includes a plurality of first sensing lines SX extending in a third direction D3 (e.g., horizontal direction) that forms an angle of +45 degrees or −45 degrees with the first direction D1, and a plurality of second sensing lines SY extending in a fourth direction D4 (e.g., vertical direction) that is perpendicular to the third direction D3. The first conductor F1 may be included in one of the plurality of first sensing lines SX, and the second conductor F2 may be included in one of the plurality of second sensing lines SY.

[0013] Figure 5 is a schematic cross-sectional view showing the operating principle of a touch sensor. When a sensing target UB, such as a finger, approaches or touches the sensor, the capacitance of a specific first sensing line SX and a specific second sensing line SY changes, causing a change in the sensing current read from them. This allows the position of the sensing target UB, such as a finger, to be identified.

[0014] As shown in FIGS. 1 and 2, the mesh wiring W1 of the first conductor F1 has a plurality of disconnection points K so that a current path can be formed throughout the entire mesh wiring W1. Similarly, the mesh wiring W2 of the second conductor F2 has a plurality of disconnection points K so that a current path can be formed throughout the entire mesh wiring W2. The mesh of each of the mesh wirings W1 and W2 may be rectangular (e.g., square) having sides parallel to the first direction D1 and sides parallel to the second direction D2. The first conductor F1 may have two disconnection points K1 and K2 aligned in the second direction D2 perpendicular to the first direction D1 in a ring-shaped portion surrounding the mesh AM. The first conductor F1 and the second conductor F2 may each have a V-shaped outer shape.

[0015] As shown in Figure 2, two disconnection points K1 and K2 formed in the annular portion surrounding the mesh AM may be defined as lattice cuts LS, and multiple lattice cuts LS may be positioned in a staggered pattern when viewed in the second direction D2. The width of the boundary portion BS (size in the second direction D2) may be equal to or less than twice the mesh diameter of the first conductor F1. In each of the mesh wiring W1 of the first conductor F1 and the mesh wiring W2 of the second conductor F2, no disconnection points may be formed in the portions extending in the second direction D2.

[0016] 6 and 7 are cross-sectional views showing the configuration of the touch sensor. FIG. 8 is a plan view showing the configuration of the touch sensor. A fifth direction D5 is the thickness direction of the mesh wiring. In the touch sensor 10, a base coat film 7, an interlayer insulating film 8, and mesh wirings W1 and W2 may be formed in this order. An overcoat film (not shown) may be formed to cover the mesh wirings W1 and W2. Each of the mesh wirings W1 and W2 may be formed of a laminate of metal films. This laminate may include a titanium film and an aluminum film.

[0017] As shown in FIGS. 2 and 6, the mesh wiring W1 of the first conductor F1 and the mesh wiring W2 of the second conductor F2 each have multiple boundary edges EK that face the boundary portions BS. In the first conductor F1, where M is the total number of boundary edges EK facing the boundary portions BS and N is the number of disconnection locations K, N / M can be set to 0.75 to 1.25. This allows the reflectance of light incident on the first and second conductors F1 and F2 in the first direction D1 to be equal to the reflectance of light incident on the first and second conductors F1 and F2 in the second direction D2, thereby effectively suppressing reflection unevenness. By setting the distance between the boundary portions BS and each disconnection location K to within 200 μm (preferably 100 μm or less), reflection unevenness can be further suppressed. The difference between the reflectance of light in the D1 direction and the D2 direction can be set to, for example, less than 10% (preferably less than 5%).

[0018] As shown in Figures 2 and 6, multiple island-shaped conductors SD may be arranged within the boundary portion BS. The island-shaped conductors SD may have an inverted tapered shape in which the length of the upper surface is shorter than the length of the lower surface. As shown in Figures 2, 7, and 8, the disconnection location K may have the shape of a wiring notch, and the notch length KL may be equal to or greater than the wiring width HW. The notch length KL may also be equal to or greater than the wiring thickness.

[0019] Fig. 9 is a schematic cross-sectional view showing the configuration of a display device according to this embodiment. As shown in Fig. 9, a display device 20 includes, in this order, a substrate 1, a pixel circuit layer 2, a light-emitting element layer 3, a sealing layer 4, and a touch sensor 10. The substrate 1, the pixel circuit layer 2, the light-emitting element layer 3, and the sealing layer 4 may form an OLED panel 9. In the display device 20, the touch sensor 10 may be monolithically formed on the OLED panel 9 (a so-called on-cell structure). The substrate 1 may be flexible.

[0020] 10 is a plan view showing the configuration of a display device according to this embodiment. In the display device 20, in a plan view, a light-emitting region 3E of each light-emitting element (e.g., an organic light-emitting diode or a quantum dot light-emitting diode) included in the light-emitting element layer 3 may be located within a mesh AM of the mesh wirings W1 and W2. Because the touch sensor 10 of this embodiment has high sensitivity, the vertical scanning period required to drive the OLED panel 9 and the sensing period of the touch sensor 10 can be overlapped (in terms of time).

[0021] (Appendix) The above-described embodiments are intended to be illustrative and explanatory, and not limiting, and many variations will be apparent to those skilled in the art based on these examples and descriptions. [Explanation of symbols]

[0022] 10 Touch Sensor 20 Display device F1 First conductor F2 Second conductor W1·W2 Braided wiring K Breakage point ED Break Edge EK boundary edges BS boundary AM (mesh)

Claims

1. a first conductor having a mesh wiring; and a second conductor adjacent to the first conductor and having a mesh wiring; At least a portion of a boundary between the first conductor and the second conductor extends in a first direction; the mesh wiring of the first conductor includes a plurality of disconnection points whose disconnection edges are formed so as to intersect with the first direction in a plan view, a difference between the reflectance of light in the first direction and the reflectance of light in a second direction perpendicular to the first direction is less than 10%; the first conductor and the second conductor each have a plurality of boundary edges facing the boundary portion; In the first conductor, when the total number of the boundary edges is M and the number of disconnection points is N, N / M=0.75 to 1.

25.

2. the second conductor is electrically insulated from the first conductor; The touch sensor according to claim 1 , wherein the mesh wiring of the second conductor includes a plurality of disconnection points whose disconnection edges are formed so as to intersect with the first direction in a plan view.

3. The touch sensor according to claim 1 , wherein the mesh wiring is optically reflective.

4. The touch sensor according to claim 1 , wherein the plurality of disconnection locations have the shape of wiring notches.

5. The touch sensor according to claim 4 , wherein the length of the notch is equal to or greater than the width of the wiring.

6. The touch sensor according to claim 4 , wherein the length of the notch is equal to or greater than the thickness of the wiring.

7. The touch sensor according to claim 1 , wherein the plurality of disconnection points are provided so that a current path can be formed throughout the mesh wiring of the first conductor.

8. The touch sensor according to claim 1 , wherein the mesh formed by the mesh wiring of the first conductor is a rectangle having a side parallel to the first direction and a side parallel to the second direction.

9. The touch sensor according to claim 1 , wherein a plurality of conductor islands are located at the boundary portion.

10. The touch sensor according to claim 1 , wherein the distance between the boundary and each disconnection point is within 200 μm.

11. The touch sensor according to claim 1 , wherein the first conductor and the second conductor each have a V-shaped outer shape.

12. the first conductor is included in one of a plurality of first sensing lines extending in a third direction that is at an angle of +45 degrees or −45 degrees with respect to the first direction; The touch sensor according to claim 1 , wherein the second conductor is included in one of a plurality of second sensing lines extending in a fourth direction perpendicular to the third direction.

13. The touch sensor according to claim 1 , wherein the mesh wiring of the first conductor has no disconnections in a portion extending in a second direction perpendicular to the first direction.

14. The touch sensor according to claim 1 , wherein the first conductor and the second conductor are each formed of a laminate of metal films.

15. The touch sensor according to claim 1 , wherein a width of the boundary portion is equal to or smaller than twice the mesh diameter of the first conductor.

16. The touch sensor according to claim 1 , wherein the disconnection edge is perpendicular to the first direction in a plan view.

17. a first conductor having a mesh wiring; and a second conductor adjacent to the first conductor and having a mesh wiring; At least a portion of the boundary between the first conductor and the second conductor extends in a first direction; the mesh wiring of the first conductor includes a plurality of disconnection points whose disconnection edges are formed so as to intersect with the first direction in a plan view, a mesh formed by the mesh wiring of the first conductor is a rectangle having a side parallel to a first direction and a side parallel to a second direction, The touch sensor has two disconnection points arranged in a second direction perpendicular to the first direction in a ring-shaped portion surrounding the mesh in the first conductor.

18. The touch sensor according to claim 17 , wherein the two disconnection locations are lattice cut portions, and the lattice cut portions are arranged in a staggered pattern when viewed in the second direction.

19. A device comprising: a first conductor having a mesh wiring; and a second conductor adjacent to the first conductor and having a mesh wiring; At least a portion of the boundary between the first conductor and the second conductor extends in a first direction; the mesh wiring of the first conductor includes a plurality of disconnection points whose disconnection edges are formed so as to intersect with the first direction in a plan view, the first conductor and the second conductor each have a plurality of boundary edges facing the boundary portion; In the first conductor, when the total number of the boundary edges is M and the number of disconnection points is N, N / M=0.75 to 1.

25.

20. The touch sensor according to any one of claims 1 to 19, A display device comprising a light-emitting element whose light-emitting region is located within the mesh of the mesh wiring in a plan view.

21. an OLED panel including the light-emitting element; The display device of claim 20 , wherein the touch sensor is monolithically formed on the OLED panel.

22. The display device of claim 21 , wherein a vertical scanning period of the OLED panel and a sensing period of the touch sensor overlap with each other.

23. 22. The display device of claim 21, wherein the OLED panel comprises a flexible substrate.

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