Pressure detection device

Abstract

To provide a pressure detection device capable of increasing the number of pressure detection per unit time.SOLUTION: A pressure detection device comprises a pressure sensor and a drive control unit. The pressure sensor includes a first circuit forming layer, a sensor layer, and a second circuit forming layer. The first circuit forming layer includes a first detection electrode, a first switching element, a first gate line, and a first gate line drive circuit. The second circuit forming layer includes a second detection electrode, a second switching element, a second gate line and a second gate line drive circuit. The first detection electrode and the second detection electrode overlap each other when viewed from the orthogonal direction. When detecting pressure at the first circuit forming layer, the drive control unit selects the first gate line in order from one side of the second direction. When detecting the pressure at the second circuit forming layer, the drive control unit selects the second gate line in order from one side of the second direction. When selecting the n-th first gate line from one side of the second direction, the drive control unit selects the second gate line other than the n-th gate line from one side of the second direction.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a pressure detection device. [Background technology]

[0002] The pressure detection device includes a pressure sensor to which pressure is input, and a drive control unit that controls the drive of the pressure sensor. The pressure sensor of the following patent document includes a circuit formation layer on which a plurality of test electrodes are provided, a common electrode facing the detection electrode, and a sensor layer sandwiched between the detection electrode and the common electrode. When no pressure is input to the pressure sensor, the sensor layer is separated from the detection electrode. When pressure is input to the pressure sensor, the sensor layer moves toward the detection electrode and comes into contact with the detection electrode. This causes a current to flow from the common electrode to the detection electrode. In addition, the current input to the detection electrode (detection result) is sent to the drive control unit via a signal line. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-146489 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand to increase the number of times pressure is detected per unit time.

[0005] An object of the present invention is to provide a pressure detection device capable of increasing the number of times pressure is detected per unit time. [Means for solving the problem]

[0006] A pressure detection device according to one aspect of the present disclosure includes a pressure sensor having a detection surface to which pressure is input, and a drive control unit that controls driving of the pressure sensor. The pressure sensor includes a base material, a first circuit-forming layer, a sensor layer, and a second circuit-forming layer that are stacked in this order in an orthogonal direction perpendicular to the detection surface. The first circuit-forming layer includes a first surface facing the sensor layer, a plurality of first detection electrodes arranged on the first surface in a first direction parallel to the detection surface and a second direction parallel to the detection surface and intersecting the first direction, a plurality of first switching elements provided corresponding to the plurality of first detection electrodes, a plurality of first gate lines extending in the first direction and provided in the second direction, connected to the first switching elements, and a first gate line driving circuit that drives the first gate lines. The second circuit-forming layer has a second surface facing the sensor layer, a plurality of second detection electrodes arranged on the second surface and arranged in the first direction and the second direction, a plurality of second switching elements provided corresponding to the plurality of second detection electrodes, a plurality of second gate lines extending in the first direction and provided in the second direction, connected to the second switching elements, and a second gate line driving circuit for driving the second gate lines. When viewed from the perpendicular direction, the first detection electrodes and the second detection electrodes overlap each other. When detecting pressure in the first circuit-forming layer, the drive control unit selects the first gate lines in order from one side of the second direction. When detecting pressure in the second circuit-forming layer, the drive control unit selects the second gate lines in order from one side of the second direction. When the drive control unit selects the n-th first gate line from one side of the second direction, the drive control unit selects the second gate lines other than the n-th from one side of the second direction. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view that illustrates a pressure detection device according to an embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing a cross section of the pressure sensor. [Diagram 3] FIG. 3 is a circuit diagram showing a circuit configuration of the first circuit-formation layer of the embodiment. [Figure 4] FIG. 4 is a schematic diagram showing a state in which pressure is input to the detection surface of the pressure sensor of the embodiment. [Diagram 5] FIG. 5 is a block diagram illustrating an example of the configuration of the pressure detection device according to the embodiment. [Figure 6] FIG. 6 is a time chart of the operation of the pressure detection device in the embodiment. [Figure 7] FIG. 7 is a schematic diagram showing an example of driving the pressure sensor of the comparative example. [Figure 8] FIG. 8 is a block diagram illustrating an example of the configuration of the pressure detection device according to the embodiment. [Figure 9] FIG. 9 is a time chart of the operation of the pressure detection device in the second embodiment. [Figure 10] FIG. 10 is a diagram for explaining a read operation in the first circuit-formation layer and a read operation in the second circuit-formation layer in the second embodiment. [Figure 11] FIG. 11 is a time chart showing the operation of the pressure detection device in the modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A detailed description will be given of a form (embodiment) for carrying out the pressure detection device of the present disclosure with reference to the drawings. The invention of the present disclosure is not limited to the contents described in the following embodiments. The components described below include those that a person skilled in the art can easily imagine and those that are substantially the same. Furthermore, the components described below can be appropriately combined. Note that the disclosure is merely an example, and those that a person skilled in the art can easily imagine appropriate modifications while maintaining the gist of the invention are naturally included in the scope of the present disclosure. In order to make the explanation clearer, the drawings may be schematic in terms of the width, thickness, shape, etc. of each part compared to the actual embodiment, but they are merely examples and do not limit the interpretation of the present disclosure. In addition, in this specification and each figure, the same reference numerals are given to components similar to those described above with respect to the previously mentioned figures, and detailed explanations may be omitted as appropriate.

[0009] Furthermore, in this specification and the claims, when expressing an aspect of arranging another structure on top of a certain structure, the term "on top" is used, unless otherwise specified, to include both the case where another structure is arranged directly on top of a certain structure so as to be in contact with the certain structure, and the case where another structure is arranged above a certain structure via yet another structure.

[0010] (Embodiment 1) Fig. 1 is a perspective view showing a pressure detection device according to an embodiment. As shown in Fig. 1, the pressure detection device 100 includes a pressure sensor 1 and a control board 80 that controls the operation of the pressure sensor 1. The control board 80 is provided with a control circuit 81 and a power supply circuit 82. The control board 80 is connected to a host 90. The host 90 is a higher-level control device that controls the pressure detection device 100.

[0011] One surface of the pressure sensor 1 is a detection surface 1a that detects pressure. The pressure sensor 1 is formed in a plate shape with a small thickness in a direction perpendicular to the detection surface 1a. When viewed from the perpendicular direction, the pressure sensor 1 is divided into a detection area 2 that detects pressure and a peripheral area 3 that does not detect pressure. The detection area 2 is located in the center of the pressure sensor 1. The peripheral area 3 is formed in a frame shape and surrounds the outside of the detection area 2.

[0012] The detection area 2 is formed into a rectangular shape in a plan view. An outer frame M of the detection area 2 has a pair of short sides 2a and a pair of long sides 2b. Hereinafter, a direction parallel to the detection surface 1a and parallel to the short sides 2a will be referred to as a first direction X. A direction parallel to the detection surface 1a and parallel to the long sides 2b will be referred to as a second direction Y. Therefore, the second direction Y is a direction perpendicular to (intersecting) the first direction X.

[0013] 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, and a pressure value is detected in each of the individual detection areas 4. The plurality of individual detection areas 4 are arranged in a first direction X and a second direction Y.

[0014] Fig. 2 is a schematic diagram showing a cross section of a pressure sensor. As shown in Fig. 2, the pressure sensor 1 includes a substrate 6, a first circuit-formation layer 10, a sensor layer 20, a second circuit-formation layer 30, and a protective layer 40, which are stacked in the orthogonal direction.

[0015] Hereinafter, among the orthogonal directions, the direction in which the second circuit-formation layer 30 is arranged as viewed from the first circuit-formation layer 10 is referred to as a first orthogonal direction Z1. The opposite direction to the first orthogonal direction Z1 is referred to as a second orthogonal direction Z2. The view from the first orthogonal direction Z1 is referred to as a plan view.

[0016] The substrate 6 is a base material that supports the first circuit-formation layer 10, and is made of a material that is not easily deformed even when a load is applied. The substrate 6 also has insulating properties. For example, the substrate 6 is made of a glass substrate, a resin substrate, or the like.

[0017] The first circuit-formation layer 10 is laminated on the substrate 6 and is integrated with the substrate 6. Although not shown, the first circuit-formation layer 10 has a laminated structure in which a plurality of insulating layers are laminated. The first circuit-formation layer 10 has a first surface 11 facing the first orthogonal direction Z1. A plurality of first detection electrodes 12 and a plurality of first common electrodes 18 are provided on this first surface 11.

[0018] The first detection electrode 12 is an electrode for detecting pressure, and is made of a metal material such as ITO (Indium Tin Oxide). The first detection electrode 12 is formed in a rectangular shape in a plan view. The first detection electrode 12 is disposed for each individual detection area 4. That is, the multiple first detection electrodes 12 are disposed in the detection area 2, and are arranged in the first direction X and the second direction Y.

[0019] A plurality of first driving transistors (first switch elements) 13 are provided inside the first circuit-forming layer 10. One first driving transistor 13 is provided for each individual detection region 4. Thus, the plurality of first driving transistors 13 are disposed in the detection region 2 and aligned in the first direction X and the second direction Y.

[0020] The first circuit-formation layer 10 includes various components for driving the first driving transistor 13. Specifically, the first circuit-formation layer 10 has a first connection portion 7 (see FIG. 1), a first gate line driving circuit 8 (see FIG. 1), a first signal line selection circuit 9 (see FIG. 1), a first gate line 14 (see FIG. 3), and a first signal line 15 (see FIG. 3).

[0021] 1, the first connection portion 7, the first gate line driving circuit 8, and the first signal line selection circuit 9 are disposed in the peripheral region 3. The first connection portion 7 is for connecting to a control board 80, and examples of such a board include a flexible printed circuit board and a rigid board.

[0022] The first gate line driving circuit 8 is a circuit that drives a plurality of first gate lines 14 (see FIG. 3) based on various control signals supplied from a control circuit 81. The first gate line driving circuit 8 sequentially selects the plurality of first gate lines 14 and supplies a gate driving signal to the selected first gate line 14. The first signal line selection circuit 9 is a switch circuit that sequentially or simultaneously selects a plurality of first signal lines 15 (see FIG. 3). The first signal line selection circuit 9 is, for example, a multiplexer. The first signal line selection circuit 9 connects the selected first signal line 15 to the control circuit 81 based on a selection signal supplied from the control circuit 81.

[0023] Fig. 3 is a circuit diagram showing a circuit configuration of the first circuit-formation layer of the embodiment. As shown in Fig. 3, the first gate lines 14 extend in the detection region 2 in a first direction X1. Furthermore, the multiple first gate lines 14 are arranged in the second direction Y. The first signal lines 15 extend in the detection region 2 in the second direction Y. Furthermore, the multiple first signal lines 15 are arranged in the first direction X.

[0024] In addition, although not shown, a first common wiring is provided in the peripheral region 3 of the first circuit-formation layer 10. The first common wiring is a wiring for supplying a current to the first common electrode 18. The first common wiring is connected to the control board 80 via the first connection portion 7, and a constant amount of current is supplied from the control circuit 81 to the first common wiring.

[0025] As shown in FIG. 2, the first driving transistor 13 includes 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 connected to the first detection electrode 12. The gate electrode 13c is connected to the first gate line 14 (see FIG. 3). The drain electrode 13d is connected to the first signal line 15 (see FIG. 3). When the first gate line 14 is driven, the first driving transistor 13 is closed. As a result, the electric signal (current) input to the first detection electrode 12 is output to the first signal line 15 via the first driving transistor 13. Then, the electric signal (current) is sent from the first signal line 15 to the control circuit 81.

[0026] The first common electrodes 18 are provided one for each individual detection region 4. Moreover, the first common electrodes 18 are spaced apart from the first detection electrodes 12. The first common electrodes 18 are connected to a first common wiring (not shown) by a wiring (not shown) that is embedded in the first circuit-formation layer 10 in the second orthogonal direction Z2 further from the first surface 11 of the first circuit-formation layer 10, and a constant amount of current is supplied to the first common electrodes 18.

[0027] The sensor layer 20 is formed in a plate shape and extends in the first direction X and the second direction Y. The sensor layer 20 has a first sensor surface 21 facing the first orthogonal direction Z1 and a second sensor surface 22 facing the second orthogonal direction Z2. The second sensor surface 22 covers the first circuit-forming layer 10 from the first orthogonal direction Z1 and is in contact with each of the first detection electrode 12 and the first common electrode 18.

[0028] The sensor layer 20 is made of a material containing conductive fine particles inside a resin layer with high insulating properties. The conductive fine particles are dispersed inside the resin layer and are separated from each other. Therefore, the sensor layer 20 has a high resistance value when the resin layer is not deformed. Therefore, although the sensor layer 20 is in contact with each of the first detection electrode 12 and the first common electrode 18, the first detection electrode 12 and the first common electrode 18 are not electrically connected. On the other hand, when the resin layer is deformed, the fine particles are in contact or in close proximity. Therefore, the resistance value of the sensor layer 20 is reduced, and the first detection electrode 12 and the first common electrode 18 are electrically connected. In addition, when the deformation amount of the resin layer increases, the amount of contact between the fine particles increases, and the resistance value of the sensor layer 20 is greatly reduced. Therefore, the amount of current flowing from the first common electrode 18 to the first detection electrode 12 increases.

[0029] Next, the second circuit-formation layer 30 will be described, but the second circuit-formation layer 30 has technical elements in common with the first circuit-formation layer 10. Therefore, in the description of the second circuit-formation layer 30, the description of the common technical elements will be simplified.

[0030] 2, the second circuit-formation layer 30 has a second surface 31 facing the second orthogonal direction Z2. A plurality of second detection electrodes 32 and a plurality of second common electrodes 38 are provided on the second surface 31. The second detection electrodes 32 are formed in a rectangular shape in a plan view, and are the same size as the first detection electrodes 12.

[0031] The second detection electrodes 32 are arranged one for each individual detection region 4. That is, the multiple second detection electrodes 32 are arranged in the detection region 2 and are arranged in the first direction X and the second direction Y. Therefore, when viewed from the orthogonal direction, the first detection electrodes 12 and the second detection electrodes 32 overlap each other. Note that, although FIG. 2 illustrates a state in which all of the first detection electrodes 12 and all of the second detection electrodes 32 overlap each other, in the present disclosure, the first detection electrodes 12 and the second detection electrodes 32 may be arranged so that at least a part of each of them overlaps.

[0032] 2, a plurality of second driving transistors (second switch elements) 33 are provided inside the second circuit-forming layer 30. One second driving transistor 33 is provided for each individual detection region 4. Although not particularly shown, the second circuit-forming layer 30 also has a second connection portion, a second gate line driving circuit, a second signal line selection circuit, a second gate line, and a second signal line in order to drive the second driving transistor 33.

[0033] The second common electrodes 38 are provided for each individual detection region 4. The second common electrodes 38 are separated from the second detection electrodes 32. The second common electrodes 38 are connected to a second common wiring (not shown) by wiring (not shown) embedded in the second circuit-forming layer 30. The second common wiring (not shown) is provided in the peripheral region of the second circuit-forming layer 30. The second common wiring is connected to the control board 80 via a second connection portion, and a constant amount of current is supplied from the control circuit 81. Therefore, a constant amount of current is supplied to the second common electrode 38.

[0034] In addition, the second circuit formation layer 30 covers the first sensor surface 21 of the sensor layer 20 in the first orthogonal direction Z1. Therefore, each of the second detection electrode 32 and the second common electrode 38 is in contact with the first sensor surface 21 of the sensor layer 20.

[0035] The protective layer 40 is formed of an elastically deformable and insulating material such as rubber or resin. The surface of the protective layer 40 facing the first orthogonal direction Z1 serves as the detection surface 1a. In the present disclosure, the protective layer 40 is not an essential component. In other words, the surface of the second circuit-formation layer 30 facing the first orthogonal direction Z1 may serve as the detection surface 1a.

[0036] Fig. 4 is a schematic diagram showing a state in which pressure is input to the detection surface of the pressure sensor of the embodiment. Next, a case in which pressure is input to the pressure sensor 1 will be described. As shown in Fig. 4, when pressure (load in the second orthogonal direction Z2, see arrow A1 in Fig. 4) is input to the detection surface 1a, the pressure is transmitted to the sensor layer 20 via the protective layer 40 and the second circuit-formation layer 30. The first sensor surface 21 of the sensor layer 20 is recessed in the second orthogonal direction Z2, and the thickness of the sensor layer 20 in the orthogonal direction is reduced.

[0037] This reduces the resistance value of the sensor layer 20, and the first detection electrode 12 and the first common electrode 18 are electrically connected. Then, a current flows from the first common electrode 18 to the first detection electrode 12 (see arrow A2). The current flowing to the first detection electrode 12 is sent to the control circuit 81 via the first signal line 15. In addition, the second detection electrode 32 and the second common electrode 38 are also electrically connected, and a current flows from the second common electrode 38 to the second detection electrode 32 (see arrow A3). The current flowing to the second detection electrode 32 is sent to the control circuit 81 via a second signal line (not shown).

[0038] From the above, when pressure is input to the detection surface 1a, the pressure is detected by each of the first circuit-formation layer 10 and the second circuit-formation layer 30. Furthermore, a first detection electrode 12 and a second detection electrode 32 are arranged for each individual detection area 4. Therefore, the pressure input for each individual detection area 4 can be detected by each of the first circuit-formation layer 10 and the second circuit-formation layer 30.

[0039] Furthermore, as the pressure (see arrow A1) increases, the deformation amount of the sensor layer 20 increases, and the reduction amount of the resistance value of the sensor layer 20 increases. That is, by measuring the value of the current flowing through the first detection electrode 12 and the second detection electrode 32, the magnitude of the input pressure can be detected.

[0040] 1, a control circuit 81 provided on a control board 80 is a control integrated circuit (IC). A power supply circuit 82 supplies power to the control circuit 81. This enables the control circuit 81 to generate a signal to be supplied to the pressure sensor 1.

[0041] 5 is a block diagram showing an example of the configuration of a pressure detection device according to an embodiment. A control circuit 81 and a power supply circuit 82 configure a drive control unit 83. The drive control unit 83 also includes a timing control unit 84, a first drive control unit 85, a second drive control unit 86, and a data transmission unit 87.

[0042] The timing control unit 84 receives a pressure detection command from the host 90, and issues sensing commands to the first drive control unit 85 and the second drive control unit 86. In addition, the timing control unit 84 shifts the timing of the sensing command to the first drive control unit 85 from the timing of the sensing command to the second drive control unit 86.

[0043] The first drive control unit 85 receives a sensing command and supplies drive signals to the first gate line drive circuit 8 and the first signal line selection circuit 9. In the first circuit formation layer 10 of this embodiment, the number of first gate lines 14 arranged in the second direction Y is K. Furthermore, the arrangement order of the gate lines (the first gate lines 14 and the second gate lines) is based on counting from one side in the second direction Y, and further, for example, the Qth arrangement is referred to as the "Qth row".

[0044] The first drive control unit 85 first drives the first gate line 14 in the first row. The first drive control unit 85 then drives the second gate line in the second row. That is, the first gate lines 14 are driven one by one from one side to the other in the second direction Y, and finally the first gate line 14 in the Kth row arranged at the other end in the second direction Y is driven. In this way, the first circuit-forming layer 10 detects the pressure input to each individual detection area 4. The first drive control unit 85 also receives the detection results (pressure value (current value) for each individual detection area 4) by the first circuit-forming layer 10 and passes them to the data transmission unit 87.

[0045] When the second drive control unit 86 receives a sensing command, it supplies a drive signal to a second gate drive circuit (not shown) and a second signal line selection circuit (not shown). In the second circuit formation layer 30, the number of second gate lines (not shown) arranged in the second direction Y is L. The number K of the first gate lines 14 is the same as the number L of the second gate lines (K=L). Therefore, the second detection electrode 32 connected to the second gate line in the first row is disposed in the individual detection area 4 in the first row from one side in the second direction Y among the multiple individual detection areas 4, and faces the first detection electrode 12 connected to the first gate line 14 in the first row. The second detection electrode 32 connected to the second gate line in the Lth row is disposed in the individual detection area 4 in the Lth row (Kth row) from one side in the second direction Y among the multiple individual detection areas 4, and faces the first detection electrode 12 connected to the first gate line 14 in the Kth row.

[0046] The driving method of the second drive control unit 86 is the same as that of the first drive control unit 85, and first drives the second gate line in the first row. Next, the second gate line in the second row is driven. In this manner, the second gate lines are driven one by one from one side to the other in the second direction Y, and finally the second gate line in the Lth row arranged at the other end in the second direction Y is driven. In this manner, the second circuit-formation layer 30 detects the pressure input to each individual detection area 4. In addition, the second drive control unit 86 receives the detection result by the second circuit-formation layer 30 (pressure value (current value) for each individual detection area 4) and passes it to the data transmission unit 87.

[0047] The data transmission unit 87 receives the detection results of the first circuit-formation layer 10 and the detection results of the second circuit-formation layer 30 , and transmits them to the host 90 .

[0048] FIG. 6 is a time chart diagram of the operation of the pressure detection device in the embodiment. Next, an example of the operation of the pressure detection device in the embodiment 1 will be described with reference to FIG. 6. In addition, in this description, as shown in FIG. 8, a case where a pressure detection command is issued from the host 90 to the timing control unit 84 to detect pressure six times in succession will be taken as an example. According to such a plurality of pressure detection commands, it is possible to detect the change over time of the pressure input to the pressure sensor 1. In addition, the time (pressure detection time) during which the pressure input to each of the plurality of individual detection areas 4 is detected by the first circuit-forming layer 10 and the time (pressure detection time) during which the pressure input to each of the plurality of individual detection areas 4 is detected by the second circuit-forming layer 30 are the same period.

[0049] The timing control unit 84 generates six sensing commands (first sensing command, second sensing command, third sensing command, fourth sensing command, fifth sensing command, and sixth sensing command). Then, the six sensing commands are sent alternately to the first drive control unit 85 and the second drive control unit 86. The time interval for sending the six sensing commands is half the pressure detection time (half the same period). Therefore, the first drive control unit 85 receives the sensing commands (first sensing command, third sensing command, fifth sensing command) at the timings of time T1, time T3, and time T5. The second drive control unit 86 receives the sensing commands (second sensing command, fourth sensing command, and sixth sensing command) at the timings of time T2, time T4, and time T6.

[0050] Therefore, the second circuit-forming layer 30 detects pressure from time T2. That is, the second gate line in the first row of the second circuit-forming layer 30 is driven from time T2. Meanwhile, at time T2, half of the pressure detection time has elapsed since the first sensing command. Therefore, in the first circuit-forming layer 10, the first gate line 14 in the K / 2th row is driven.

[0051] At time T3, the first circuit-forming layer 10 drives the first gate line 14 in the first row in response to the third sensing command. Also, at time T3, the second circuit-forming layer 30 drives the second gate line (not shown) in the L / 2th row. Therefore, in the first circuit-forming layer 10 and the second circuit-forming layer 30, different numbers of gate lines are driven, counting from one side in the second direction Y. Also, at times T4, T5, and T6, the driven gate lines are shifted in the second direction Y in the first circuit-forming layer 10 and the second circuit-forming layer 30. From the above, in the first circuit-forming layer 10 and the second circuit-forming layer 30, the driven gate lines are shifted in the second direction Y.

[0052] As described above, in the first embodiment, the pressure input to the pressure sensor 1 can be detected by each of the first circuit-formation layer 10 and the second circuit-formation layer 30. Furthermore, in a conventional pressure sensor having a single circuit-formation layer, the second sensing is performed after the first sensing is completed. On the other hand, according to the present embodiment, the second sensing can be performed before the first sensing is completed. Therefore, the number of pressure detections per unit time increases, and the detection time of the pressure sensor 1 can be shortened.

[0053] Furthermore, when sensing is performed simultaneously on the first circuit-forming layer 10 and the second circuit-forming layer 30, the gate lines of the same number of rows are driven. Therefore, as shown in Fig. 4, a current may flow from the first common electrode 18 of the first circuit-forming layer 10 to the second detection electrode 32 of the second circuit-forming layer 30 (see arrow A4 in Fig. 4), or a current may flow from the second common electrode 38 of the second circuit-forming layer 30 to the first detection electrode 12 of the first circuit-forming layer 10 (see arrow A5 in Fig. 4).

[0054] On the other hand, in this embodiment, when the first gate line 14 driven by the first circuit-forming layer 10 is the nth (nth row) counting from one side in the second direction Y, the second gate line driven by the second circuit-forming layer 30 is the (n+(L / 2))th ((n+(L / 2))th row) or (n-(L / 2))th ((n-(L / 2))th row) counting from one side in the second direction Y. That is, when the nth first gate line 14 counting from one side in the second direction Y is driven, the second gate line other than the nth counting from one side in the second direction Y is driven. Therefore, it is prevented that a current flows from the first common electrode 18 to the second detection electrode 32 (see arrow A4 in FIG. 4) or a current flows from the second common electrode 38 to the first detection electrode 12 (see arrow A5 in FIG. 4). Therefore, the reliability of the sensing result is not impaired.

[0055] Although the first embodiment has been described above, the present disclosure is not limited to the example shown in the first embodiment. For example, in the first embodiment, multiple pressure detection commands sent from the host 90 are distributed as sensing commands to the first circuit-forming layer 10 and the second circuit-forming layer 30, but multiple detection operations may be performed upon receiving one pressure detection command from the host 90, and an average pressure value may be calculated. Details will be described below using a comparative example.

[0056] In the first embodiment, while one gate line is driven, multiple signal lines are selected in sequence or simultaneously. This allows a current value (detection result) to be read out from a detection electrode connected to the gate line. In the first embodiment, while one gate line is driven, a read operation (detection operation) is performed once. With this driving method, since the read operation (detection operation) is performed once, there is a possibility that noise may be input during the readout, and the reliability of the detected pressure value is low.

[0057] FIG. 7 is a schematic diagram showing an example of driving a pressure sensor of a comparative example. On the other hand, in the comparative example, as shown in FIG. 7, while one gate line is being driven (when the gate line in FIG. 7 is "ON"), multiple read operations are performed (four times in the comparative example). In other words, while one gate line is being driven, the detection result is read from the detection electrode, and then the detection result is read from the detection electrode again, and this is repeated. This results in multiple (four) detection results. In addition, an average value can be calculated from the multiple (four) detection results, and this average value can be used as the pressure value. According to this driving method, even if noise is input to one of the multiple read operations, the effect of the noise is reduced because the average value is calculated. Therefore, the reliability of the detected pressure value is high.

[0058] In the next embodiment 2, a pressure detection device 100A in which a read operation is performed four times and an average value is taken as a pressure value will be described. In addition, in the embodiment 2, the description will focus on the differences from the embodiment 1.

[0059] (Embodiment 2) Fig. 8 is a block diagram showing a configuration example of a pressure detection device according to an embodiment. As shown in Fig. 8, the pressure detection device 100A has a drive control unit 83A instead of the drive control unit 83. The drive control unit 83A has a timing control unit 84A, a first drive control unit 85A, a second drive control unit 86A, and a data transmission unit 87A.

[0060] The first drive control unit 85A differs from the first drive control unit 85 in that, when a sensing command is received from the timing control unit 84A, while one first gate line 14 is being driven, each of the first signal lines 15 is selected twice and the read operation is performed twice.

[0061] Similarly, the second drive control unit 86A differs from the second drive control unit 86 in that, when a sensing command is received, while one second gate line is being driven, each of the second signal lines is selected twice and the read operation is performed twice.

[0062] In this manner, in the second embodiment, the four read operations are divided so that they are performed two times on each of the first circuit-formation layer 10 and the second circuit-formation layer 30.

[0063] The data transmission unit 87A receives a total of four detection results sent from each of the first drive control unit 85A and the second drive control unit 86A. The data transmission unit 87A also calculates an average value from the four detection results and sends the average value to the host 90 as a pressure value.

[0064] The timing control unit 84A differs from the timing control unit 84 of the first embodiment in that it generates two sensing commands when it receives one pressure detection command from the host 90. That is, two sensing commands are generated to cause each of the first circuit-formation layer 10 and the second circuit-formation layer 30 to execute four read operations.

[0065] 9 is a time chart of the operation of the pressure detection device in the second embodiment. In addition, there is a time lag between the timing of sending a sensing command to the first drive control unit 85A and the timing of sending a sensing command to the second drive control unit 86. Specifically, as shown in FIG. 9, the timing control unit 84A sends a sensing command to the first drive control unit 85A at time T11. Thereafter, the timing control unit 84A sends a sensing command to the second drive control unit 86A at time T12. The interval between time T11 and time T12 is the time it takes for one gate line to be driven and two readout operations to be completed.

[0066] As described above, according to the pressure detection device 100A of the second embodiment, the first gate line 14 in the first row is driven in the first circuit-forming layer 10 between time T11 and time T12. The first gate line 14 in the second row is driven in the first circuit-forming layer 10, and the second gate line in the first row is driven in the second circuit-forming layer 30 between time T12 and time T13. The first gate line 14 in the third row is driven in the first circuit-forming layer 10, and the second gate line in the second row is driven in the second circuit-forming layer 30 between time T13 and time T14.

[0067] 10 is a diagram for explaining the readout operation in the first circuit-forming layer and the readout operation in the second circuit-forming layer in the second embodiment. As shown in FIG. 10, between time T11 and time T12, the readout operation is performed twice for the first detection electrode 12 connected to the first gate line 14 in the first circuit-forming layer 10. Between time T12 and time T13, the readout operation is performed twice for the second detection electrode 32 connected to the second gate line in the first row in the second circuit-forming layer 30. From the above, the pressure input to the first row individual detection region 4 arranged at one end in the second direction Y among the multiple individual detection regions 4 is detected four times.

[0068] Furthermore, between time T12 and time T13, a read operation is performed twice for the first detection electrodes 12 connected to the first gate lines 14 in the second row in the first circuit-forming layer 10. Between time T13 and time T14, a read operation is performed twice for the second detection electrodes 32 connected to the second gate lines in the second row in the second circuit-forming layer 30. As a result, the pressure input to the individual detection regions 4 in the second row is detected four times.

[0069] As described above, in the second embodiment, the first and second readout operations are performed in the first circuit-formation layer 10, and the third and fourth readout operations are performed in the second circuit-formation layer 30. In this manner, detection can be performed in each of the first circuit-formation layer 10 and the second circuit-formation layer 30. Therefore, the number of detection operations is approximately twice as many as in the case where there is a single circuit-formation layer, and the amount of detection results per unit time is greater.

[0070] In addition, in the second embodiment, when the first gate line 14 driven by the first circuit-formation layer 10 is the nth (nth row) counting from one side in the second direction Y, the second gate line driven by the second circuit-formation layer 30 is the (n-1)th ((n-1)th row) counting from one side in the second direction Y. That is, the gate lines driven by the first circuit-formation layer 10 and the second circuit-formation layer 30 are shifted by one in the second direction Y. This prevents a current from flowing from the first common electrode 18 to the second detection electrode 32 (see arrow A4 in FIG. 4) or from flowing from the second common electrode 38 to the first detection electrode 12 (see arrow A5 in FIG. 4).

[0071] Furthermore, in the four read operations, as soon as the second read operation by the first circuit-formation layer 10 is completed, the third read operation by the second circuit-formation layer 30 is performed. This prevents the pressure value from fluctuating between the end of the second read operation and the start of the third read operation. This makes the pressure value (average value) highly reliable.

[0072] In addition, since there are two circuit-formed layers, for example, a driving method is conceivable in which the pressure input to the individual detection regions 4 arranged in odd-numbered rows is read out four times in the first circuit-formed layer 10, and the pressure input to the individual detection regions 4 arranged in even-numbered rows is read out four times in the second circuit-formed layer 30. According to this, the first circuit-formed layer 10 and the second circuit-formed layer 30 cannot absorb errors in the detection capabilities during manufacturing. On the other hand, in this embodiment, the four read operations are allocated to the first circuit-formed layer 10 and the second circuit-formed layer 30, two each. Therefore, errors in the detection capabilities during manufacturing are absorbed by the first circuit-formed layer 10 and the second circuit-formed layer 30.

[0073] In the second embodiment, the first circuit-formation layer 10 and the second circuit-formation layer 30 are shifted in the second direction Y by one gate line to be driven, but in the present disclosure, the gate lines to be driven may be shifted in the second direction Y by two or more. However, the second embodiment is preferable because it is less likely to cause fluctuations in the pressure value.

[0074] In addition, in the second embodiment, detection is started from the first circuit-formation layer 10, but detection may be started from the second circuit-formation layer 30. In such a case, when the first gate line 14 driven by the first circuit-formation layer 10 is the nth (nth row) counting from one side in the second direction Y, the second gate line driven by the second circuit-formation layer 30 is the (n+1)th ((n+1)th row) counting from one side in the second direction Y.

[0075] FIG. 11 is a time chart of the operation of the pressure detection device in the modified example. In addition, the present disclosure may perform multiple detection operations for each of multiple pressure detection commands sent from the host 90, and the average value may be the pressure value. Specifically, as shown in FIG. 11, when three pressure detection commands are received from the host 90, the timing control unit 84A generates two first sensing commands. Then, at time T21, the first first sensing command is sent to the first circuit-forming layer 10, and at time T22, the second first sensing command is sent to the second circuit-forming layer 30. The interval between time T21 and time T22 is the time it takes for one gate line to be driven and two read operations to be completed.

[0076] Furthermore, the timing control unit 84A generates two second sensing commands, sends the first second sensing command to the first circuit-forming layer 10 at time T23, and sends the second second sensing command to the second circuit-forming layer 30 at time T24. Note that time 23 is the time when the first sensing by the first circuit-forming layer 10 ends. Furthermore, the timing control unit 84A generates two third sensing commands, sends the first third sensing command to the first circuit-forming layer 10 at time T25, and sends the second third sensing command to the second circuit-forming layer 30 at time T26.

[0077] According to this modification, a total of three sensings, the first sensing, the second sensing, and the third sensing, are performed with intervals between each other, so that it is possible to detect changes in the pressure value over time. Also, the first sensing, the second sensing, and the third sensing each perform a read operation four times, and the average value is the pressure value. Therefore, the reliability of the information (pressure value) is high.

[0078] In addition, the sensor layer 20 of the embodiment is made of a material containing conductive fine particles inside the resin layer, but the present disclosure is not limited to this. For example, the sensor layer may be formed of a conductive resin, and the detection electrode and the common electrode may be electrically connected to each other by increasing the contact area between the detection electrode and the common electrode. [Explanation of symbols]

[0079] 1 Pressure Sensor 2. Detection Area 3. Surrounding Areas 4 Individual detection areas 6 Substrate 10 First circuit forming layer 11 Page 1 12 First detection electrode 18 1st common electrode 20 Sensor Layer 30 Second circuit forming layer 31 Side 2 32 Second detection electrode 38 2nd common electrode 80 Control Board 81 Control circuit 82 Power supply circuit 83 Drive control unit 84 Timing control section 85 First drive control section 86 Second drive control section 87 Data transmission section 100 Pressure detection device

Claims

1. a pressure sensor having a detection surface to which pressure is input; A drive control unit that controls the drive of the pressure sensor; Equipped with The pressure sensor includes a base material, a first circuit-forming layer, a sensor layer, and a second circuit-forming layer, which are stacked in this order in a direction perpendicular to the detection surface, The first circuit formation layer is a first surface facing the sensor layer; a plurality of first detection electrodes disposed on the first surface and arranged in a first direction parallel to the detection surface and in a second direction parallel to the detection surface and intersecting the first direction; a plurality of first switching elements provided corresponding to the plurality of first detection electrodes, respectively; a plurality of first gate lines extending in the first direction and provided in the second direction, the first gate lines being connected to the first switching elements; a first gate line driving circuit for driving the first gate line; having The second circuit formation layer is a second surface facing the sensor layer; a plurality of second detection electrodes disposed on the second surface and arranged in the first direction and the second direction; a plurality of second switching elements provided corresponding to the plurality of second detection electrodes, respectively; a plurality of second gate lines extending in the first direction and provided in the second direction, the second gate lines being connected to the second switching elements; a second gate line driving circuit for driving the second gate line; having When viewed from the orthogonal direction, the first detection electrode and the second detection electrode overlap each other, The drive control unit is When detecting pressure in the first circuit formation layer, the first gate lines are selected in sequence from one side in the second direction; When detecting pressure in the second circuit formation layer, the second gate lines are selected in sequence from one side in the second direction; When the n-th first gate line is selected from one side in the second direction, the second gate line other than the n-th second gate line is selected from one side in the second direction. Pressure sensing device.

2. a pressure detection time by the first circuit-forming layer and a pressure detection time by the second circuit-forming layer are the same period, The timing at which the pressure of the first circuit-forming layer starts to be detected and the timing at which the pressure of the second circuit-forming layer starts to be detected are shifted by half the time of the same period. The pressure detection device according to claim 1 .

3. When the n-th first gate line from one side in the second direction is selected, the (n+1)-th or (n-1)-th second gate line from one side in the second direction is selected. The pressure detection device according to claim 1 .

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