pressure sensor

Abstract

To provide a pressure sensor which becomes a closed circuit under no load as well.SOLUTION: The pressure sensor includes: an array substrate having a plurality of array electrodes on a first surface; a node in the array substrate, the node being supplied with a constant potential; a sensor layer facing the first surface; and a plurality of bypass wires provided in the array substrate, the bypass wires connecting the array electrodes and the node. The resistance value of the bypass wires is larger than that of the sensor layer.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a pressure sensor.

Background Art

[0002] The pressure sensor in the following patent document includes an array substrate provided with a plurality of array electrodes, a sensor layer facing the array electrodes, and a counter electrode corresponding to the array electrodes sandwiching the sensor layer. In the pressure sensor, the surface on which the sensor layer is arranged as viewed from the array substrate is a detection region for detecting pressure. When pressure acts on the detection region, the counter electrode and the sensor layer deform toward the array substrate, and the sensor layer contacts the array electrodes. As a result, a current flows from the counter electrode to the array electrodes through the sensor layer. Further, the sensor layer has conductive particles dispersed in an insulating resin. When the resin deforms, the conductive particles come into contact with each other, and the resistance value of the sensor layer decreases. When the resin is greatly deformed, the number of conductive particles in contact with each other increases, and the resistance value of the sensor layer greatly decreases. Therefore, when the pressure input to the pressure sensor increases, the current value flowing through the array electrodes also increases. On the other hand, when the load acting on the pressure sensor is zero, the sensor layer does not contact the array electrodes, and the array electrodes and the counter electrode are not electrically connected. That is, the circuit for detecting the current value input to the array electrodes is an open circuit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Incidentally, in sensor elements, baseline correction is widely known, in which the detected value (pressure value) is measured based on the output value output from the sensor element when there is no stimulus (no load). Such correction can reduce the influence of external noise. On the other hand, the pressure sensor described above has a circuit that opens and closes during measurement. As a result, the output value may differ significantly, or the circuit constants of the time constant may differ. In other words, baseline correction becomes difficult, and the measurement accuracy may decrease.

[0005] The present invention aims to provide a pressure sensor that forms a closed circuit even under no load. [Means for solving the problem]

[0006] A pressure sensor according to a first aspect of the present disclosure comprises an array substrate having a plurality of array electrodes on its first surface, a node provided on the array substrate and supplied with a constant potential, a sensor layer facing the first surface, and a plurality of bypass wires provided on the array substrate and connecting each of the plurality of array electrodes to the node, wherein the resistance of the bypass wires is greater than the resistance of the sensor layer.

[0007] A pressure sensor according to a second aspect of the present disclosure comprises an array substrate having a first surface, a common electrode provided on the first surface, and a sensor layer facing the first surface. The array substrate includes a plurality of array electrodes provided on the first surface, a plurality of common electrodes provided on the first surface, a plurality of first gate lines, a plurality of second gate lines, a plurality of drive transistors whose gate electrodes are connected to the first gate lines and which drive the array electrodes, and a plurality of bypass transistors whose gate electrodes are connected to the second gate lines, whose drain electrodes are connected to the array electrodes, and whose source electrodes are connected to the common electrodes. The resistance of the bypass transistors is greater than the resistance of the sensor layer. . [Brief explanation of the drawing]

[0008] [Figure 1]Figure 1 is a cross-sectional view showing the cross-sectional structure of the pressure sensor according to Embodiment 1. [Figure 2] Figure 2 is a cross-sectional view of the section cut along line II-II shown in Figure 1, viewed from the direction of the arrow. [Figure 3] Figure 3 is a circuit diagram showing the circuit configuration of the pressure sensor of Embodiment 1. [Figure 4] Figure 4 is a plan view of the array electrodes, common electrodes, and bypass wiring shown in Figure 2, as seen from the sensor layer. [Figure 5] Figure 5 shows the state in which the detection surface of the pressure sensor of Embodiment 1 is pressed by a finger. [Figure 6] Figure 6 is a cross-sectional view showing a cross-section of the pressure sensor of modified example 1. [Figure 7] Figure 7 is a cross-sectional view showing a cross-section of the pressure sensor of modified example 2. [Figure 8] Figure 8 is a cross-sectional view showing a cross-section of the pressure sensor of Embodiment 2. [Figure 9] Figure 9 is a circuit diagram showing the circuit configuration of the pressure sensor of Embodiment 2. [Figure 10] Figure 10 is a cross-sectional view showing a cross-section of the pressure sensor of Embodiment 3. [Figure 11] Figure 11 is a circuit diagram showing the circuit configuration of the pressure sensor according to Embodiment 3. [Figure 12] Figure 12 is a cross-sectional view showing a cross-section of the pressure sensor of modified example 3. [Figure 13] Figure 13 is a cross-sectional view showing a cross-section of the pressure sensor according to the modified example 4. [Figure 14] Figure 14 is a cross-sectional view of the pressure sensor in modified example 4 when pressure is input. [Modes for carrying out the invention]

[0009] Embodiments for implementing the pressure sensor of this disclosure will be described in detail with reference to the drawings. The invention of this disclosure is not limited by the contents described in the following embodiments. Furthermore, the components described below include those that can be easily conceived by a person skilled in the art, and those that are substantially the same. In addition, the components described below can be combined as appropriate. It should be noted that the disclosure is merely an example, and any modifications that can be easily conceived by a person skilled in the art while maintaining the spirit of the invention are naturally included within the scope of the present invention. In order to make the explanation clearer, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and each drawing, components that are the same as those described above with respect to previously shown drawings are denoted by the same reference numerals, and detailed explanations may be omitted as appropriate.

[0010] Furthermore, in this specification and the claims, when describing a manner in which one structure is placed on top of another structure, unless otherwise specified, the term "on top of" includes both cases: when one structure is placed directly on top of another structure so as to be in contact with it, and when another structure is placed above another structure via yet another structure.

[0011] (Embodiment 1) Figure 1 is a schematic perspective view of a pressure sensor according to Embodiment 1. As shown in Figure 1, the pressure sensor 1 has a detection surface 1a for detecting pressure and is flat in shape. Viewed from the direction normal to the detection surface 1a, the pressure sensor 1 is rectangular in shape. Viewed from the direction normal to the detection surface 1a, the detection surface 1a of the pressure sensor 1 is divided into a detection area 2 in which pressure can be detected and a peripheral area 3 surrounding the outside of the detection area. In Figure 1, a boundary line L is drawn to make the detection area 2 and the peripheral area 3 easier to see. Furthermore, the detection area 2 is divided into a plurality of individual detection areas 4. In other words, the detection area 2 is a collection of a plurality of individual detection areas 4.

[0012] The plurality of individual detection regions 4 are arranged in the first direction Dx and the second direction Dy. The first direction Dx is a direction parallel to the detection surface 1a. The second direction Dy is parallel to the detection surface 1a and intersects the first direction Dx. In the present embodiment, the first direction Dx is a direction parallel to the short side of the pressure sensor 1. Also, the second direction Dy is a direction parallel to the long side of the pressure sensor 1. That is, the first direction Dx and the second direction Dy are orthogonal to each other. Also, the normal direction of the detection surface 1a is a direction orthogonal to each of the first direction Dx and the second direction Dy, and may be referred to as the third direction Dz.

[0013] FIG. 2 is a cross-sectional view of the cross-section cut along the line II-II shown in FIG. 1 as viewed from the arrow direction. As shown in FIG. 2, the pressure sensor 1 includes a substrate 5, an array layer 10, an array electrode 20, a common electrode 30, a bypass wiring 40, a sensor layer 50, and a protective layer 60.

[0014] The substrate 5 is an insulating substrate. For the substrate 5, for example, a glass substrate, a resin substrate, a resin film, or the like is used. In the following description, the upper side is one direction of the third direction Dz, and refers to the side on which the array layer 10 is arranged when viewed from the substrate 5.

[0015] The array layer 10 is provided with a driving transistor 13 in each individual detection region. Also, the array layer 10 includes various components for driving the driving transistor 13. Specifically, as shown in FIG. 1, the array layer 10 has a connection portion 7, a gate line driving circuit 8, a signal line selection circuit 9, a gate line 11 (see FIG. 3), and a signal line 12 (see FIG. 3). Note that the array layer 10 and the substrate 5 are integrated to form an array substrate 6.

[0016] The connection section 7, gate line drive circuit 8, and signal line selection circuit 9 are located in the peripheral region 3 of the array layer 10. The connection section 7 is for connecting to a drive IC (Integrated Circuit) located outside the pressure sensor 1. The drive IC may be mounted as COF (Chip On Film) on a flexible printed circuit board connected to the connection section 7 or on a rigid circuit board. Alternatively, the drive IC may be mounted as COG (Chip On Glass) in the peripheral region 3 of the substrate 5.

[0017] The gate line drive circuit 8 is a circuit that drives multiple gate lines 11 (see Figure 3) based on various control signals from the drive IC. The gate line drive circuit 8 sequentially or simultaneously selects multiple gate lines 11 and supplies gate drive signals to the selected gate lines 11. The signal line selection circuit 9 is a switch circuit that sequentially or simultaneously selects multiple signal lines 12 (see Figure 3). The signal line selection circuit 9 is, for example, a multiplexer. Based on the selection signals supplied from the drive IC, the signal line selection circuit 9 connects the selected signal lines 12 to the drive IC.

[0018] Figure 3 is a circuit diagram showing the circuit configuration of the pressure sensor of Embodiment 1. As shown in Figure 3, the gate lines 11 extend in the first direction Dx. Multiple gate lines 11 are arranged in the second direction Dy. The signal lines 12 extend in the second direction Dy. Multiple signal lines 12 are arranged in the first direction Dx. In addition, although not specifically shown, the array layer 10 has common wiring that extends along the peripheral region 3. The common wiring is connected to the drive IC via the connection part 7, and a fixed amount of current is supplied from the drive IC.

[0019] A driving transistor 13 is provided in each individual detection region 4. As shown in Figure 2, the driving transistor 13 comprises a semiconductor layer 13a, a gate insulating film 13b, a gate electrode 13c, a drain electrode 13d, and a source electrode 13e. The source electrode 13e is electrically connected to the array electrode 20. The gate electrode 13c is connected to the gate line 11. The drain electrode 13d is connected to the signal line 12. As a result, when the gate line 11 is scanned, the electrical state of the array electrode 20, in other words, the electrical signal (current value) input to the array electrode 20, is obtained via the signal line 12. This allows for the detection of the pressure acting on the individual detection region 4.

[0020] Furthermore, the first surface 6a of the array substrate 6 facing the sensor layer 50 is flattened by an insulating layer 14 that covers the drive transistors 13 and the like.

[0021] The array electrodes 20, common electrodes 30, and bypass wiring 40 are provided on the first surface 6a of the array substrate 6. The array electrodes 20, common electrodes 30, and bypass wiring 40 are manufactured from a metallic material such as ITO (Indium Tin Oxide). In this disclosure, the array electrodes 20, common electrodes 30, and bypass wiring 40 may be manufactured from different metallic materials and are not particularly limited.

[0022] The common electrode 30 is connected to a common wiring (not shown) by wiring (not shown) embedded in the insulating layer 14 of the array layer 10. Therefore, a constant amount of current is supplied to the common electrode 30 from the drive IC.

[0023] Figure 4 is a plan view of the array electrode, common electrode, and bypass wiring shown in Figure 2, viewed from the sensor layer. As shown in Figure 4, the array electrode 20 and common electrode 30 form a rectangular shape in plan view. The array electrode 20 and common electrode 30 are separated from each other in the first direction Dx. The bypass wiring 40 is positioned between the array electrode 20 and the common electrode 30. One end 40a of the bypass wiring 40 is connected to the array electrode 20. The other end 40b of the bypass wiring 40 is connected to the common electrode 30. Therefore, the array electrode 20 and the common electrode 30 are connected via the bypass wiring 40. In this embodiment, the common electrode 30 corresponds to the node to which the bypass wiring 40 is connected.

[0024] As shown in Figure 4, the middle portion of the bypass wiring 40 has multiple U-shaped curved sections 40c in a plan view, which extend in a second direction Dy perpendicular to the first direction Dx in which the array electrodes 20 and the common electrode 30 are separated, and return from its end. In other words, the bypass wiring 40 meanders between the array electrodes 20 and the common electrode 30, making it longer. Therefore, the resistance value of the bypass wiring 40 is higher than that of a straight shape that connects the array electrodes 20 and the common electrode 30 by the shortest distance. Furthermore, because it has curved sections 40c, the resistance value of the bypass wiring 40 in this embodiment is greater than the resistance value of the sensor layer 50 when detecting the smallest pressure value detectable by the pressure sensor 1.

[0025] The sensor layer 50 is manufactured from a material containing conductive fine particles within a highly insulating resin layer. The fine particles are dispersed within the resin layer and are spaced apart from each other. Therefore, the resistance of the sensor layer 50 is high when the resin layer is not deformed. On the other hand, when the resin layer deforms, the fine particles come into contact or are close together, and the resistance of the sensor layer 50 decreases. Furthermore, as the amount of deformation of the resin layer increases, the amount of contact between the fine particles increases, and the resistance of the sensor layer 50 decreases significantly. The sensor layer 50 is sometimes called a pressure-sensitive layer.

[0026] As shown in Figure 2, the sensor layer 50 is supported by a spacer (not shown) provided on the array substrate 6 and is located on the upper side of the array substrate 6. The sensor layer 50 faces the array electrodes 20, the common electrode 30, and the bypass wiring 40 in the third direction Dz. A space S is provided below the sensor layer 50, separating it from the array electrodes 20, the common electrode 30, and the bypass wiring 40. The spacer (not shown) may be provided in the peripheral region 3 of the first surface 6a of the array substrate 6, or between individual detection regions 4, and is not particularly limited in this disclosure.

[0027] The protective layer 60 is an insulating layer positioned above the sensor layer 50 and extending along the sensor layer 50. The protective layer 60 is integrated with the sensor layer 50 by an adhesive layer (not shown). The upper surface of the protective layer 60 is the detection surface 1a.

[0028] Figure 5 shows the state in which the detection surface of the pressure sensor of Embodiment 1 is pressed by a finger. As shown in Figure 5, when the detection surface 1a is pressed by a finger 100, the protective layer 60 and a part of the sensor layer 50 deform so as to be indented toward the array substrate 6. As a result, the sensor layer 50 comes into contact with the array electrode 20 and the common electrode 30. The resistance value of the sensor layer 50 decreases due to the deformation caused by the press. Therefore, the sensor layer 50 electrically connects the array electrode 20 and the common electrode 30. As a result, current flows from the common electrode 30 to the array electrode 20, and it is possible to detect that pressure has been applied to the detection surface 1a.

[0029] Furthermore, as the pressure from the fingers 100 increases, the deformation of the sensor layer 50 increases. Consequently, the reduction in the resistance of the sensor layer 50 increases. In addition, as the pressure from the fingers 100 increases, the contact area of ​​the sensor layer 50 that contacts the array electrode 20 and the common electrode 30 increases, and the current flowing through the array electrode 20 also increases. Therefore, by measuring the magnitude of the current input to the array electrode 20, the magnitude of the pressure applied to the detection surface 1a can be detected.

[0030] Next, the circuit configuration of the individual detection region 4 in the array substrate 6 will be described. As shown in Figure 3, the array electrode 20 is electrically connected to the common electrode 30 by bypass wiring 40. Therefore, when no load is input to the pressure sensor 1, a gate drive signal is input to the gate line 11, and when the signal line 12 is selected, the current value input to the array electrode 20 is output to the signal line 12 via the bypass wiring 40.

[0031] On the other hand, when a load is input to the pressure sensor 1, the sensor layer 50 comes into contact with the array electrode 20 and the common electrode 30. In other words, the sensor layer 50 and the bypass wiring 40 are connected in parallel between the array electrode 20 and the common electrode 30. If the resistance of the bypass wiring 40 is smaller than the resistance of the sensor layer 50, no current will flow through the sensor layer 50, and the magnitude of the pressure cannot be measured. However, in this embodiment, the resistance of the bypass wiring 40 is greater than the resistance of the sensor layer 50. Specifically, the resistance of the bypass wiring 40 is greater than the resistance of the sensor layer 50 when the input value of the electrical signal input to the array electrode 20 via the sensor layer 50 is at its minimum. Therefore, the current supplied from the common electrode 30 does not pass through the bypass wiring 40, but always flows through the sensor layer 50. The current value input to the array electrode 20 via the sensor layer 50 is then output to the signal line 12.

[0032] From the above, according to the pressure sensor 1 of Embodiment 1, the circuit becomes a closed circuit even under no-load conditions. In other words, the response to external noise becomes constant, and baseline correction becomes easy.

[0033] The pressure sensor 1 of Embodiment 1 has been described above, but the pressure sensor of this disclosure is not limited to that exemplified in Embodiment 1. For example, the resistance value of the bypass wiring 40 only needs to be greater than the resistance value of the sensor layer 50 when the input value of the electrical signal input to the array electrode 20 via the sensor layer 50 is at its minimum, and there is no particular method for increasing (adjusting) the resistance value of the bypass wiring 40. For example, the material of the bypass wiring 40 may be changed to one with a high resistance value. Also, if a material with a high resistance value is used, the bypass wiring 40 may be made straight instead of meandering as in the embodiment. Furthermore, if the bypass wiring 40 is made meandering, it is not necessary to make the entire bypass wiring 40 meandering, but rather to make at least a part of the bypass wiring 40 meandering. In addition, although the bypass wiring 40 of Embodiment 1 is arranged on the first surface 6a, this disclosure is not limited to this. Modifications 1 and 2 in which the bypass wiring is not arranged on the first surface 6a will be described below.

[0034] (Variation 1) Figure 6 is a cross-sectional view showing a cross-section of the pressure sensor of Modification 1. As shown in Figure 6, the bypass wiring 40A of the pressure sensor 1A of Modification 1 is embedded in the insulating layer 14. That is, the bypass wiring 40A is located inside the insulating layer 14 and is not placed on the first surface 6a of the array substrate 6. Therefore, even if the detection surface 1a is pressed and the sensor layer 50 moves toward the first surface, the bypass wiring 40A does not come into contact with the sensor layer 50. This prevents the bypass wiring 40A from being pressed and broken by the sensor layer 50. In addition, since the bypass wiring 40A of Modification 1 wraps around in the third direction Dz, the resistance value can be increased. Note that in Modification 1, the entire bypass wiring 40A is embedded inside the insulating layer 14, but in this disclosure, at least a portion of the bypass wiring 40A may be embedded inside the insulating layer 14.

[0035] (Modification 2) Figure 7 is a cross-sectional view showing a cross-section of the pressure sensor of Modification 2. As shown in Figure 7, the bypass wiring 40B of the pressure sensor 1B of Modification 2 comprises a first bypass wiring 41 made of a metal material and connected to the array electrode 20, a second bypass wiring 42 made of a metal material and connected to the common electrode 30, and a bypass semiconductor layer 43 connected to the first bypass wiring 41 and the second bypass wiring 42. The bypass semiconductor layer 43 is manufactured from the same material as the semiconductor layer 13a of the drive transistor 13. In other words, the bypass semiconductor layer 43 is produced at the same time as the semiconductor layer 13a of the drive transistor 13. Therefore, the manufacturing of the bypass semiconductor layer 43 is easy. In summary, according to Modification 2, the bypass semiconductor layer 43 is included in the bypass wiring 40B. Therefore, the resistance value can be increased compared to when the entire bypass wiring 40B is made of a metal material.

[0036] (Embodiment 2) Figure 8 is a cross-sectional view showing a cross-section of the pressure sensor of Embodiment 2. Figure 9 is a circuit diagram showing the circuit configuration of the pressure sensor of Embodiment 2. The pressure sensor 1C of Embodiment 2 differs from the pressure sensor 1 of Embodiment 1 in that the common electrode 30 is positioned between the sensor layer 50 and the protective layer 60 and acts as a counter electrode facing the array electrode 20 in the third direction Dz. The pressure sensor 1C of Embodiment 2 also differs from Embodiment 1 in that a ground electrode 70 is provided on the array substrate 6.

[0037] The ground electrode 70 is located below the first surface 6a and is embedded in the insulating layer 14. Therefore, it does not come into contact with the sensor layer 50. The ground electrode 70 is connected to the array electrode 20 by a bypass wiring 40C. As shown in Figure 9, the ground electrode 70 is connected to the ground wiring 71. In this embodiment, the ground electrode 70 corresponds to the node to which the bypass wiring 40 is connected. The ground wiring 71 extends from the electrode to the connection part 7. Ground current is supplied to the ground electrode 70 from the drive IC.

[0038] As described above, the pressure sensor of Embodiment 2 forms a closed circuit even under no load. Therefore, the same effects as in Embodiment 1 can be obtained. In addition, this disclosure may apply the bypass wiring of the above-described modification to the pressure sensor of Embodiment 2.

[0039] (Embodiment 3) Figure 10 is a cross-sectional view showing a cross-section of the pressure sensor of Embodiment 3. Figure 11 is a circuit diagram showing the circuit configuration of the pressure sensor of Embodiment 3. The pressure sensor 1D of Embodiment 3 differs from the pressure sensor of Embodiment 1 in that it is equipped with a bypass transistor 80 instead of bypass wiring. The bypass transistor 80 comprises a semiconductor layer 80a, a gate insulating film 80b, a gate electrode 80c, a drain electrode 80d, and a source electrode 80e. The drain electrode 80d is connected to the array electrode 20. The source electrode is connected to the common electrode 30. As shown in Figure 11, the gate electrode 80c is connected to the gate wire 11.

[0040] According to Embodiment 3, when a drive signal is input to the gate electrode 13c of the drive transistor 13 via the gate wire 11, the drive signal is also input to the gate electrode 80c of the bypass transistor 80. The common electrode 30 is then connected to the array electrode 20 via the bypass transistor 80. Here, when no pressure is applied to the detection surface 1a, current supplied from the common electrode 30 flows through the array electrode 20. On the other hand, when pressure is applied to the detection surface 1a, current supplied from the common electrode 30 flows through the sensor layer 50, which has a lower resistance value than the bypass transistor 80. Thus, according to Embodiment 3, a closed circuit is formed even when there is no load. Therefore, the same effects as in Embodiment 1 can be obtained.

[0041] Although each embodiment has been described above, the sensor layer of this disclosure is not limited to those described above. Other forms of the sensor layer will be described below.

[0042] (Variation 3) Figure 12 is a cross-sectional view showing a cross-section of the pressure sensor of Modified Example 3. The sensor layer 50E of the pressure sensor 1E of Modified Example 3 is provided between the first surface 6a of the array substrate 6 and the protective layer 60. The sensor layer 50E is in contact with the array electrode 20, the common electrode 30, and the bypass wiring 40 even before deformation. As described in Embodiment 1, this sensor layer 50E contains conductive fine particles inside an insulating resin. According to this sensor layer 50, it is in an insulating state when no pressure is applied, that is, when it is not deformed. When pressure is applied and it deforms, the resistance value decreases, and the common electrode 30 and the array electrode 20 become electrically connected. Also, as the pressure increases, the amount of deformation of the sensor layer 50E increases, and the amount of current flowing to the array electrode 20 increases. On the other hand, even if the pressure increases, the contact area between the sensor layer 50E and the common electrode 30 and the array electrode 20 does not change. In other words, it differs from the sensor layer 50 of Embodiment 1 in that it does not have the function of changing the amount of current flowing to the array electrode 20 due to an increase or decrease in the contact area.

[0043] (Modification 4) Figure 13 is a cross-sectional view showing a cross-section of the pressure sensor of Modified Example 4. Figure 14 is a cross-sectional view of the pressure sensor of Modified Example 4 when pressure is input. The sensor layer 50F of the pressure sensor 1F of Modified Example 4 has two protrusions 51 that project toward the array electrode 20 and the common electrode 30. The tips of the protrusions 51 are in contact with either the array electrode 20 or the common electrode 30. The sensor layer 50F is manufactured from ITO or a semiconductor material and is made of a material with high insulating properties. In this state, the contact area between the tips of the protrusions 51 and the array electrode 20 and the common electrode 30 is small. Therefore, the sensor layer 50F does not electrically connect the array electrode 20 and the common electrode 30.

[0044] On the other hand, as shown in Figure 14, when the detection surface 1a is pressed, the sensor layer 50F collapses in the third direction Dz, and the contact area of ​​the protrusion 51 with the array electrode 20 and the common electrode 30 increases. As a result, the sensor layer 50F electrically connects the array electrode 20 and the common electrode 30, and current flows through the array electrode 20. Furthermore, as the pressure acting on the sensor layer 50F increases, the contact area between the protrusion 51 and the array electrode 20 and the common electrode 30 increases, and the amount of current flowing through the sensor layer 50F also increases. Therefore, the amount of current input to the array electrode 20 by the sensor layer 50F increases in proportion to the increase in contact area. This makes it possible to detect the magnitude of the pressure input to the detection surface 1a.

[0045] In addition, while the sensor layer 50F of Modified Example 4 is given as an example of how the resistance value of the sensor layer changes due to an increase or decrease in the contact area, the pressure sensor of this disclosure may also use sensor layers of shapes or arrangements other than the sensor layer 50F, and is not particularly limited. Furthermore, although the entire sensor layer 50F of Modified Example 4 is manufactured from the same material, a separate main body may be formed from an insulating material such as resin, and a sensor layer made from the same material as the sensor layer may be provided on the surface of the main body. Even in such an example, the contact area of ​​the sensor layer covering the main body changes due to the pressing of the detection surface 1a, and the magnitude of the pressure can be detected. [Explanation of Symbols]

[0046] 1, 1A, 1B, 1C, 1D, 1E, 1F Pressure Sensors 1a Detection surface 2 Detection area 3. Peripheral area 4 Individual detection area 5 circuit boards 6 Array substrate 6a 1st page 10 array layers 13. Drive transistors 13a Semiconductor layer 11 Gate Line 12 signal lines 20 Array electrodes 30 Common electrode (electrode) 40, 40A, 40B bypass wiring 41 First Bypass Wiring 42 Second Bypass Wiring 43 Bypass semiconductor layer 50, 50E, 50F sensor layers 51 Convex part 60 protective layer 70 Ground electrode (electrode) 71 Ground Wiring 80 Bypass Transistors

Claims

1. An array substrate having multiple array electrodes on its first surface, A node provided on the array substrate to which a constant potential is supplied, A sensor layer facing the first surface and in contact with the array electrodes and the nodes by pressing, The array substrate is provided with a plurality of bypass wires connecting each of the plurality of array electrodes to the node, Equipped with, The resistance value of the bypass wiring is greater than the resistance value of the sensor layer. The aforementioned array substrate is A driving transistor for driving the aforementioned array electrodes, A bypass semiconductor layer manufactured from the same material as the semiconductor layer of the aforementioned drive transistor, It has, The bypass semiconductor layer is included in the bypass wiring. Pressure sensor.

2. The aforementioned node is a common electrode. The pressure sensor according to claim 1.

3. The node is a ground electrode embedded in the array substrate. The pressure sensor according to claim 1.

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