Touch panel system, display device, and control method of touch panel

Abstract

Provided are a touch panel system, a display device, and a control method of a touch panel capable of detecting a position and a press while suppressing the influence of heat from a finger and the surroundings. The touch panel system includes a touch panel of an electrostatic capacitance type and a controller that controls the touch panel. The touch panel includes a plurality of drive electrodes (12) and a plurality of floating island electrodes (12) on a first substrate, and a plurality of press detection electrodes (21) and a plurality of position detection electrodes (22) on a second substrate. The controller supplies a drive signal to the plurality of drive electrodes and corrects a press detection signal obtained from each press detection electrode using a position detection signal obtained from the position detection electrodes.

Description

Technical Field

[0001] This disclosure relates to a touch panel system, a display device, and a method for controlling the touch panel. Background Technology

[0002] In recent years, touch panels have been widely used in smartphones, tablets, and car dashboards. Patent document 1 discloses a touch panel that detects the position and pressure of pointers such as fingers or pens. Existing technical documents Patent documents

[0003] Patent Document 1: Japanese Patent Application Publication No. 2015-75892 Summary of the Invention The technical problem to be solved by the present invention

[0004] The touch panel disclosed in Patent Document 1 includes a thermoelectric element. It detects the proximity of a finger through the thermoelectric effect of the thermoelectric element and detects finger pressure through the piezoelectric effect of the thermoelectric element. Therefore, even when a different heat-generating object approaches the touch panel, there is a possibility that the proximity of the heat-generating object may be mistaken for the proximity of a finger. Furthermore, conversely, when the temperature of the touch panel's thermoelectric element and the finger are at the same level, it is difficult to achieve a thermoelectric effect, making it difficult to detect the finger's position.

[0005] The purpose of this disclosure is to provide a touch panel system, display device, and control method for detecting position and pressure by suppressing the effects of finger and surrounding heat. Technical solutions for solving technical problems

[0006] A touch panel system according to a certain embodiment of this disclosure includes: an electrostatic capacitive touch panel; and a controller that controls the touch panel. The touch panel includes: a first substrate and a second substrate; a first dielectric layer located between the first substrate and the second substrate; a plurality of driving electrodes located on the first substrate; a plurality of floating island electrodes located on the first substrate; a plurality of press detection electrodes located on the second substrate; and a plurality of position detection electrodes located on the second substrate. In a top view, each driving electrode overlaps with at least a portion of its corresponding press detection electrode, and each floating island electrode overlaps with at least a portion of its corresponding position detection electrode. The controller provides driving signals to the plurality of driving electrodes and corrects press detection signals obtained from each press detection electrode using position detection signals obtained from the position detection electrodes. Beneficial effects

[0007] According to one embodiment of the present disclosure, a touch panel system is able to detect position and press while suppressing the influence of the indicator and heat in the usage environment. Attached Figure Description

[0008] Figure 1 This is a block diagram showing the configuration of the touch panel system according to the first embodiment. Figure 2 This is a schematic cross-sectional view showing the configuration of a display device equipped with a touch panel system. Figure 3 This is a magnified schematic diagram showing the cross-sectional structure of the touch panel. Figure 4 This is a top view showing the structure of the electrodes on the touch panel. Figure 5 This is a top view showing the structure of the electrodes on the touch panel. Figure 6 This indicates the overlap between the floating island electrode and the driving electrode and the position detection electrode when viewed from above. Figure 7 This indicates the overlap between the floating island electrode and the driving electrode and the press detection electrode and the shielding electrode when viewed from above. Figure 8 This is a block diagram illustrating an example of a controller in a touch panel system according to the first embodiment. exist Figure 9 The diagram in the middle represents the electric field lines corresponding to the capacitive coupling generated between the indicator and various electrodes. Figure 10 This is an example of the measurement results of the position detection signal and the press detection signal detected by the position detection electrode and the press detection electrode respectively when the indicator touches the touch panel. Figure 11 It means to Figure 10 The image shows the amplified position detection signal and the press detection signal. Figure 12 Indicates using Figure 10 The press detection signal shown is the press detection signal after the position detection signal has been corrected. Figure 13 This is a schematic diagram showing an enlarged cross-sectional structure of the touch panel according to the second embodiment. Figure 14 This is a schematic diagram illustrating the temperature dependence of the relative permittivity of the first dielectric layer and the second dielectric layer in the second embodiment. Figure 15 This is a schematic diagram showing an enlarged cross-sectional structure of the touch panel according to the third embodiment. Figure 16 This is a schematic diagram illustrating the temperature dependence of the relative permittivity of the first and third dielectric layers in the third embodiment. Figure 17 This is a schematic diagram showing an enlarged cross-sectional structure of the touch panel according to the fourth embodiment. Figure 18 This is a schematic diagram showing an enlarged cross-sectional structure of the touch panel according to the fourth embodiment. Detailed Implementation

[0009] Hereinafter, embodiments of the present disclosure will be described based on the accompanying drawings. The present disclosure is not limited to the following embodiments, and design changes can be appropriately made within the scope of the configuration of the present disclosure. Furthermore, in the following description, sometimes the same reference numerals are used in different drawings for the same part or parts having the same function, and repeated descriptions are omitted. Furthermore, the configurations described in the embodiments and other embodiments can be appropriately combined and modified without departing from the spirit of the present disclosure. For ease of understanding, the configurations in the following referenced drawings are sometimes simplified or schematically represented, or some components are omitted. The dimensional ratios between the components shown in the figures do not necessarily represent actual dimensional ratios. "Row direction" refers to the horizontal direction (X direction) of the display device's screen, and "column direction" refers to the vertical direction (Y direction) of the display device's screen. Furthermore, in the following referenced drawings, various electrodes are indicated by shaded lines for easy identification.

[0010] [First Implementation Method] Figure 1 This is a block diagram illustrating the configuration of the touch panel system 301 according to the first embodiment. The touch panel system 301 includes a touch panel 101 and a controller 201. The touch panel 101 is configured as a capacitive touch panel. Specifically, the touch panel 101 is configured to receive a drive signal Sd from the controller 201 and output a signal s1 representing a capacitance change related to the position of the indicator and a signal s2 representing a capacitance change related to the pressing of the indicator.

[0011] The controller 201 provides a drive signal Sd to the touch panel 101, and uses signals S1 and S2 as position detection signals and press detection signals, respectively, to detect and correct the press detection signals using the position detection signals. Furthermore, it outputs position information I1 and press information I2 based on the position detection signals and the corrected press detection signals.

[0012] Figure 2 This is a cross-sectional schematic diagram showing the configuration of a display device 401 equipped with a touch panel system 301. The display device 401 includes a touch panel system 301 and a display 410. The display 410 displays images on a display surface 410a. The touch panel 101 of the touch panel system 301 is disposed on the display surface 410a. The display 410 is, for example, a liquid crystal display or an organic EL (Electro-Luminescence) display.

[0013] The operator touches a specific location on the surface of the touch panel 101 using a finger, stylus, or other pointer, according to the information displayed on the display surface 410a. The touch panel system 301 detects the location of the touch and the intensity of the pressure, and outputs location information I1 and pressure information I2. This output information is input to control devices such as smartphones, portable terminals, and microcomputers that control car navigation systems, which are equipped with the display device 401, and is used to control the images displayed on the display device 401 and to control these devices. As will be explained in detail below, the touch panel system 301 of this embodiment suppresses false detections by suppressing the thermal effects caused by the temperature of the operating environment of the touch panel 101 or the temperature difference between the operating environment and the pointer. The structure and operation of the touch panel system 301 will be explained in detail below.

[0014] (Structure of the touch panel) Figure 3 This is a magnified schematic diagram showing the cross-sectional structure of the touch panel 101. Furthermore, Figure 4 as well as Figure 5 This is a top view showing the structure of the electrodes on the touch panel 101. Figure 3 The location of the cross section shown is in Figure 4 and Figure 5 The middle section is represented by line III-III.

[0015] The touch panel 101 includes a first substrate 10 and a second substrate 20, a first dielectric layer 31, a plurality of driving electrodes 12, a plurality of floating island electrodes 11, a plurality of position detection electrodes 21, and a plurality of press detection electrodes 22. The touch panel 101 also includes a plurality of shielding electrodes 23.

[0016] The first substrate 10 has a thin plate shape having a first main surface 10a and a second main surface 10b located opposite to the first main surface 10a. Similarly, the second substrate 20 also has a thin plate shape having a first main surface 20a and a second main surface 20b located opposite to the first main surface 20a. The first substrate 10 and the second substrate 20 are arranged such that the second main surface 10b of the first substrate 10 faces the first main surface 20a of the second substrate 20. In this specification, "facing" means a positional relationship in which they are opposite to each other.

[0017] The first substrate 10 and the second substrate 20 are made of transparent materials such as glass and PET (Polyethylene terephthalate) film.

[0018] The first dielectric layer 31 is located between the first substrate 10 and the second substrate 20, and is made of a transparent material that is elastic and insulating. For example, various transparent polymer materials can be used for the first dielectric layer 31. Specifically, commercially available materials such as OCA (Optical Clear Adhesive, OCR) and OCR (Optical Clear Resin, OCR) can be used. Preferably, the first dielectric layer 31 does not have thermoelectric properties.

[0019] The touch panel 101 is attached to the display 410, for example, by an adhesive layer 50 such as OCA.

[0020] Multiple driving electrodes 12 and multiple floating island electrodes 11 are located on the second main surface 10b of the first substrate 10. For example... Figure 4 As shown, the plurality of driving electrodes 12, for example, have a plurality of bases 12c having a rhomboid shape arranged in a matrix in the row direction (x-axis direction) and column direction (y-axis direction), and a plurality of connecting portions 12d connecting the plurality of bases 12c in the row direction and column direction. The connecting portions 12d are cut off by slits 12e in the column direction. Therefore, in each driving electrode 12, the bases 12c are connected only in the row direction. The plurality of driving electrodes 12 extending in the row direction are arranged in the column direction.

[0021] Each of the multiple floating island electrodes 11 has an octagonal shape, for example, formed by cutting four vertices of a rhombus, and is disposed in one of the multiple gaps formed by the driving electrode 12. That is, the multiple floating island electrodes 11 are independent rhombus electrodes that are not connected to each other.

[0022] On the second main surface 20b of the first substrate 10, each base 12c of the driving electrode 12 is adjacent to and surrounded by four floating island electrodes 11, and each floating island electrode 11 is adjacent to and surrounded by the four bases 12c of the driving electrode 12.

[0023] Multiple position detection electrodes 21, multiple pressure detection electrodes 22, and multiple shielding electrodes 23 are located on the first main surface 20a of the second substrate 20. For example... Figure 5 As shown, multiple position detection electrodes 21 are arranged in a matrix, for example, in the row and column directions, and include multiple bases 21c with a rhomboid shape, and multiple connecting portions 21d connecting the multiple bases 21c in the column direction. The two vertices on the diagonal of each base 21c in the row direction are cut off.

[0024] Multiple pressure detection electrodes 22, for example, have multiple bases 22c arranged in a matrix in the row and column directions, and multiple connecting portions 22d connecting the multiple bases 22c in the row direction.

[0025] Multiple position detection electrodes 21 and multiple press detection electrodes 22 extend along the column direction, and are alternately arranged in the row direction. Multiple shielding electrodes 23 each have a serrated shape extending in the column direction and are located between the position detection electrodes 21 and the press detection electrodes 22. That is, a pair of shielding electrodes 23 are located on both sides of a press detection electrode 22 in the row direction. Each shielding electrode 23 has a base 23c and a connecting portion 23d that are respectively adjacent to the base 22c and the connecting portion 22d of the press detection electrode 22. The two shielding electrodes 23 adjacent to a press detection electrode 22 in the row direction have a shape that integrally offsets one of the position detection electrodes 21 by half a pitch in both the row and column directions.

[0026] Figure 6 and Figure 7 This indicates that the floating island electrode 11 and driving electrode 12 located on the first substrate 10 overlap with the position detection electrode 21, press detection electrode 22, and shielding electrode 23 located on the second substrate 20 when viewed from above. Here, "viewing from above" means observing these electrodes along a direction perpendicular to the first main surface 10a of the first substrate 10.

[0027] Figure 6 and Figure 7 In the image, for ease of understanding, the floating island electrode 11 and the driving electrode 12 are not shaded and are represented in white. Figure 6 The press detection electrode 22 and the shielding electrode 23 are not indicated. Figure 7 Position detection electrode 21 is not indicated.

[0028] like Figure 6 As shown, at least a portion of each floating island electrode 11 overlaps with the position detection electrode 21. Specifically, each floating island electrode 11 substantially overlaps with the base 21c of the position detection electrode 21. The base 12c of the driving electrode 12 preferably does not overlap with the position detection electrode 21. On the other hand, as... Figure 7 As shown, at least a portion of the driving electrode 12 overlaps with at least a portion of the shielding electrode 23 and the press detection electrode 22. Specifically, the base 12c of the driving electrode 12 overlaps with the base 23c of the shielding electrode 23 and the base 22c of the press detection electrode 22. Preferably, the area of ​​the shielding electrode 23 overlapping with the driving electrode 12 is smaller than the area of ​​the press detection electrode 22 overlapping with the driving electrode 12. The larger area of ​​the press detection electrode 22 allows for more accurate detection of the intensity of the press based on the indicator.

[0029] (Controller configuration) Figure 8This is a block diagram illustrating an example of controller 201. Controller 201 includes a drive unit 51, a charge detection unit 52, an ADC (Analog to Digital Converter) 53, a correction unit 54, and a signal processing unit 55.

[0030] The drive unit 51 includes a signal generator, etc., which generates a drive signal Sd and applies the drive signal Sd to the plurality of drive electrodes 12. In addition, the shielding electrode 23 is connected to a reference potential such as ground potential.

[0031] The charge detection unit 52 receives signals s1 output from each position detection electrode 21 and signals s2 output from each press detection electrode 22. Signals s1 and s2 include information related to changes in electrostatic capacitance caused by touch or heat of the indicator. The charge detection unit 52 converts signals s1 and s2 into electrostatic capacitance values ​​or voltage values ​​proportional to the changes, and outputs position detection signal S1 and press detection signal S2. That is, the charge detection unit 52 detects signals s1 output from each position detection electrode 21 and signals s2 output from each press detection electrode 22, and outputs position detection signal S1 and press detection signal S2. The charge detection unit 52 obtains position detection signal S1 and press detection signal S2 based on the position detection electrode 21 and press detection electrode 22, respectively. The charge detection unit 52 can be configured, for example, by a detection circuit including a general integrating circuit such as an operational amplifier.

[0032] The ADC53 includes, for example, a sample-and-hold circuit and an A / D converter, which receives the position detection signal S1 and the press detection signal S2 and converts them into digital signals.

[0033] The correction unit 54 corrects the press detection signals S2 obtained from each press detection electrode 22 based on the position detection signal S1 obtained from the position detection electrode 21 adjacent to the press detection electrode 22, and generates a corrected press detection signal S2'. Furthermore, the correction unit 54 stores the position detection signal S1 in a memory or the like, and outputs the position detection signal S1 and the corrected press detection signal S2'. As described in detail below, the relative permittivity of the first dielectric layer 31 depends on temperature. Therefore, in the event of heat affecting the touch panel 101, changes in the relative permittivity of the first dielectric layer 31 may affect changes in the electrostatic capacitance to be detected.

[0034] In the touch panel system of this embodiment, taking advantage of the fact that the position detection signal S1 obtained from the position detection electrode 21 is also affected by heat, the position detection signal S1 is used to reduce the influence of the change in capacitance caused by heat from the press detection signal S2. For example, by amplifying the position detection signal S1 and subtracting the amplified position detection signal S1' from the press detection signal S2, a corrected press detection signal S2' is generated.

[0035] The correction unit 54 can be constructed from logic circuits based on FPGA or the like, or it can be executed by software as a function of the signal processing unit 55 described below.

[0036] The signal processing unit 55 includes a microcomputer and a memory. It receives a position detection signal S1 and a corrected press detection signal S2', and generates a two-dimensional mapping related to the position of the indicator and the intensity of the press. The generated two-dimensional mapping corresponds to the first main surface 10a of the first substrate 10 of the touch panel. Specifically, a position detection mapping is generated based on the position detection signal S1, and a press detection mapping is generated based on the corrected press detection signal S2'. These mappings are output as position information I1 and press information I2. Furthermore, the signal processing unit 55 controls the drive unit 51, the charge detection unit 52, the ADC 53, and the correction unit 54.

[0037] (Actions related to the touch panel) Next, refer to Figure 9 The operation of the touch panel system 301 will be explained. Figure 9 In the diagram, dashed lines L1, L2, and L3 represent the capacitive coupling between the indicator F and various electrodes, and the corresponding electric field lines corresponding to the capacitive coupling between the various electrodes. For example... Figure 9 As shown, when the indicator F contacts the touch panel 101, as indicated by dashed line L1, the driving electrode 12 and the floating island electrode 11 are capacitively coupled by capacitor C1. At this time, as indicated by dashed line L3, the floating island electrode 11 and the position detection electrode 21 are capacitively coupled by capacitor C3. Therefore, the driving electrode 12 and the position detection electrode 21 are capacitively coupled via the floating island electrode 11. The combined capacitor C is a series connection of capacitors C1 and C3, denoted by C = (C1·C3) / (C1+C3). Generally, the capacitance C1 formed between adjacent electrodes is smaller than the capacitance C3 formed by opposite electrodes, therefore, capacitance C is smaller than capacitance C3. Therefore, due to the contact between the indicator F and the touch panel 101, the electrostatic capacitance between the driving electrode 12 and the position detection electrode 21 decreases, and the signal s1 obtained from the position detection electrode 21, i.e., the position detection signal S1, changes.

[0038] In addition, such as Figure 9As shown by the dashed line L2, the driving electrode 12 and the press detection electrode 22 are capacitively coupled by a capacitor C2. Here, when a press (load) is applied to the first substrate 10 via the indicator F, since the first dielectric layer 31 is an elastic material, the distance between the driving electrode 12 and the press detection electrode 22 decreases in the pressed portion. Consequently, the electrostatic capacitance C2 between the driving electrode 12 and the press detection electrode 22 increases, and the signal s2 obtained from the press detection electrode 22 and the press detection signal S2 change.

[0039] Furthermore, the driving electrode 12 is configured to overlap with the shielding electrode 23 when viewed from above, and the shielding electrode 23 is positioned between the position detection electrode 21 and the press detection electrode 22. Therefore, the electric field lines extending from the end of the driving electrode 12 preferentially face the shielding electrode 23 and are unlikely to reach the position detection electrode 21. That is, the driving electrode 12 cannot be directly capacitively coupled to the position detection electrode 21 without passing through the floating island electrode 11. Therefore, the position detection signal S1 is less susceptible to changes in electrostatic capacitance caused by the indicator F applying a load to the first substrate 10 and the driving electrode 12 displacing towards the second substrate 20.

[0040] Next, the effect of heat will be explained. When the pointer F, which serves as a finger, is in contact with the touch panel 101, if the temperature of the touch panel 101 at ambient temperature is lower than the temperature of the pointer F, then... Figure 9 As shown by the shaded area H, heat is transferred from the indicator F to the first dielectric layer 31. Therefore, the temperature of the first dielectric layer 31 rises. Generally, when the dielectric is a polymer material, the relative permittivity of the dielectric increases with increasing temperature.

[0041] Figure 10 This is an example of a press detection signal S2 detected by the press detection electrode 22 and a position detection signal S1 detected by the position detection electrode 21. These signals represent changes in electrostatic capacitance on the touch panel 101 detected by the press detection electrode 22 and the position detection electrode 21, respectively. With the indicator F in contact with the touch panel 101 as a reference, the horizontal axis represents time, and the vertical axis represents the change in capacitance. The horizontal and vertical axes can be arbitrary units.

[0042] The pressure detection signal S2 increases sharply after the indicator F makes contact, and then the rate of change decreases, approaching a certain value. This indicates that as the indicator F contacts the first main surface 10a of the first substrate 10, the temperature of the first dielectric layer 31 rises, the relative permittivity of the first dielectric layer 31 between the driving electrode 12 and the pressure detection electrode 22 increases, and the electrostatic capacitance C2 increases. Thus, when the temperature of the first dielectric layer 31 rises, even though the indicator F is not pressed into the first substrate 10, the electrostatic capacitance changes, and the pressure detection signal S2 obtained from the pressure detection electrode 22 changes.

[0043] On the other hand, the position detection signal S1 obtained from the position detection electrode 21 depends on the combined capacitance C of the series-connected capacitors C1 and C3. Through contact between the indicator F and the touch panel 101, the temperature of the first substrate 10 and the first dielectric layer 31 rises, and the relative permittivity of the materials of the first dielectric layer 31 and the first substrate 10, which form part of the capacitor C1, also changes. However, since the floating island electrode 11 and the driving electrode 12 are not opposite each other, the change in the relative permittivity of these materials has a small impact on the capacitor C1. Therefore, as... Figure 10 As shown, the change in position detection signal S1 is less than the change in pressure detection signal S2.

[0044] Depend on Figure 10 It can be seen that the position detection signal S1 and the press detection signal S2 change at approximately the same timing, showing the same trend. This is because, although the magnitudes of the effects are different, the position detection signal S1 and the press detection signal S2 are also affected by the heat transferred from the indicator F at approximately the same time. Therefore, it can be considered that if the amplitude of the signals in the position detection signal S1 and the press detection signal S2 is adjusted in a way that makes the effect of the change in electrostatic capacitance caused by heat equal, the effect of heat caused by touching the indicator F can be suppressed.

[0045] Figure 11 This represents the amplified position detection signal S1', which is the result of amplifying the press detection signal S2 and the position detection signal S1 by a factor of 13. For example... Figure 11 As shown, the magnified position detection signal S1' and the press detection signal S2 change very consistently.

[0046] Figure 12 This represents the corrected press detection signal S2' obtained by subtracting the amplified position detection signal S1' from the press detection signal S2 and the press detection signal S2'. For example... Figure 12 As shown, the increase in capacity caused by heat can be suppressed. Therefore, by correcting the press detection signal S2 using the position detection signal S1, the effects caused by heat can be suppressed. The amplification ratio, i.e., the amplification rate of the position detection signal S1, can be determined to minimize the thermal effects in the press detection signal S2. Even if the detection of the intensity of the touch based on the indicator is canceled out in the press detection signal S2 by performing such correction, the amplification rate can be set relatively low to maintain the necessary detection sensitivity. The amplification rate depends on the shape, arrangement, and area of ​​the electrodes in the touch panel 101, as well as the thickness and relative permittivity of the insulating materials such as the first substrate 10, the second substrate 20, and the first dielectric layer 31 in the touch panel. Therefore, an appropriate amplification rate can be determined based on simulation, actual measurement, etc.

[0047] Thus, the touch panel system according to this embodiment can detect both the position of the indicator and the intensity of the press based on the indicator F using an electrostatic capacitive method without the use of thermoelectric elements. Furthermore, when there is a large temperature difference between the indicator and the touch panel, the influence of the indicator's temperature on the press detection can be suppressed.

[0048] Furthermore, according to the touch panel system of this embodiment, the position detection signal S1, which is detected simultaneously, is used to correct the press detection signal S2, thus enabling appropriate correction of the effects of rapid heat (noise). For example, Japanese Patent Application Publication No. 2012-43394 discloses that in an embedded touch panel, a moving average of the periodically acquired detection signals of the touch panel is taken to reduce noise caused by the drive signal of the display. When such a noise suppression method is used to suppress the effects of changes in the dielectric constant caused by heat, it is difficult to accurately suppress the effects of heat because the rapid changes in the relative dielectric constant are averaged over time. In addition, because averaging is performed, the changes in the dielectric constant have a longer time-dependent effect. In this regard, the touch panel system of this embodiment can more effectively suppress the effects of heat from the finger and its surroundings.

[0049] [Second Implementation] Figure 13 This is an enlarged cross-sectional view of the touch panel of the touch panel system according to the second embodiment. In this embodiment, the touch panel 102 differs from the touch panel 101 and touch panel system 301 of the first embodiment in that it also includes a cover layer 40 and a second dielectric layer 32. The cover layer 40 is located on the first main surface 10a side of the first substrate 10. Furthermore, the second dielectric layer 32 is located between the cover layer 40 and the first substrate 10.

[0050] The cover layer 40 is located on the outermost surface of the touch panel 102 and protects the surface of the touch panel 102. The cover layer 40 is made of transparent materials such as resin and glass.

[0051] By positioning the second dielectric layer 32 on the first main surface 10a side of the first substrate 10, the second dielectric layer 32 can adjust the capacity that affects the position detection signal S1 obtained from the position detection electrode 21. The second dielectric layer 32 can also function as an adhesive for bonding the cover layer 40 to the first substrate 10.

[0052] The second dielectric layer 32 can be made of the same material as the first dielectric layer 31. By using the same material, the change in relative permittivity due to heat conduction from the indicator when the indicator contacts the touch panel—that is, the temperature characteristics of the relative permittivity—is the same in both the first and second dielectric layers 31. Therefore, by amplifying the position detection signal S1 and subtracting the amplified position detection signal S1' from the press detection signal S2, the thermal effects in the press detection signal S2 can be suppressed more accurately.

[0053] The second dielectric layer 32 can be made of a different material than the first dielectric layer 31. When the first dielectric layer 31 is made of a first material and the second dielectric layer 32 is made of a second material, and the first and second materials are different, it is preferable that the relative permittivity of the first and second materials exhibits the same trend with respect to temperature. Figure 14 As shown, for example, in the case of a temperature characteristic ε1 where the relative permittivity of the first material increases with increasing temperature, it is preferable that the relative permittivity of the second material also increases with increasing temperature, ε2. The temperature characteristic of the relative permittivity is not limited to a linear function; it can also be a quadratic function, etc. Furthermore, if temperature characteristics ε1 and ε2 are linear functions, their slopes can be different. Even if the first and second materials are different, since the relative permittivity changes with temperature in the same direction, the position detection signal S1 can be used to suppress the thermal effects in the pressure detection signal S2.

[0054] When the second dielectric layer 32 is made of a different material than the first dielectric layer 31, the second material preferably has a larger elastic modulus than the first material. Therefore, when a load is applied to the touch panel 102 by the indicator, the first dielectric layer 31 deforms more than the second dielectric layer 32, thus increasing the displacement of the drive electrode 12. This, in turn, increases the variation in the press detection signal S2.

[0055] [Third Implementation Method] Figure 15 This is an enlarged cross-sectional view of the touch panel of the touch panel system according to the third embodiment. The touch panel system of this embodiment differs from the touch panel 102 and touch panel system of the second embodiment in that the touch panel 103 includes a third dielectric layer 33. The third dielectric layer 33 is, for example, located between the first dielectric layer 31 and the second substrate 20. The third dielectric layer 33 is made of a third material. The third material differs from the first material; preferably, the relative permittivity of the first and third materials exhibits opposite trends with respect to temperature.

[0056] like Figure 16As shown, for example, in the case where the relative permittivity of the first material increases with increasing temperature (temperature characteristic ε1), the relative permittivity of the third material is preferably decreasing with increasing temperature (temperature characteristic ε3). By reversing the tendency of the relative permittivity to change, at least a portion of the change in relative permittivity due to temperature rise or fall can cancel each other out in the laminated structure combining the first dielectric layer 31 and the third dielectric layer 33. Therefore, as in Figure 16 As indicated by the dashed line, in the temperature characteristic ε13 of the stacked structure combining the first dielectric layer 31 and the third dielectric layer 33, the increase or decrease of the relative permittivity decreases with increasing temperature. As a result, when the position detection signal S1 is used to correct the press detection signal S2, the amplification factor of the position detection signal S1 can be reduced, and the thermal effects can be reduced from the press detection signal S2 with higher accuracy.

[0057] [Fourth Implementation Method] Figure 17 and Figure 18 An enlarged cross-sectional view of the touch panel of the touch panel system according to the fourth embodiment. Figure 17 The touch panel 104 shown and Figure 18 The positions of the floating island electrode 11, driving electrode 12, position detection electrode 21, press detection electrode 22, and shielding electrode 23 in the touch panel 105 shown are different from those in the touch panel 101 of the first embodiment. Specifically, in Figure 17 In the touch panel 104 shown, the position detection electrode 21, the press detection electrode 22, and the shielding electrode 23 are located on the second main surface 20b of the second substrate 20. Furthermore, Figure 18 In the touch panel 105 shown, the floating island electrode 11 and the driving electrode 12 are located on the first main surface 10a of the first substrate 10.

[0058] Even in a touch panel system including touch panel 104 and touch panel 105, as described in detail in the first embodiment, the influence of the temperature of the indicator on the detection of the press can be suppressed even when there is a large temperature difference between the indicator and the touch panel.

[0059] [Other methods] The touch panel, touch panel system, and touch panel control method disclosed herein are not limited to the embodiments described above and can be modified in various ways. For example, the controller may also process signals using a method different from that described in the above embodiments. Furthermore, the shapes of the driving electrode, floating island electrode, position detection electrode, press detection electrode, and shielding electrode shown in the above embodiments are just examples, and these electrodes may also have other shapes.

[0060] Furthermore, in the above embodiments, an example was described where the relative permittivity of the dielectric layer increases due to the approach of a finger towards the touch panel. However, even when the relative permittivity of the dielectric layer decreases due to the approach of a finger, i.e., an indicator with a temperature higher than the touch panel, the touch panel system of this disclosure can suppress the effects of heat.

[0061] The touch panel system, display device, and control method of the touch panel disclosed herein can also be described as follows.

[0062] The first configuration of the touch panel system includes: a capacitive touch panel; and a controller that controls the touch panel. The touch panel includes: a first substrate and a second substrate; a first dielectric layer located between the first substrate and the second substrate; a plurality of driving electrodes located on the first substrate; a plurality of floating island electrodes located on the first substrate; a plurality of press detection electrodes located on the second substrate; and a plurality of position detection electrodes located on the second substrate. In a top view, each driving electrode overlaps at least a portion with its corresponding press detection electrode, and each floating island electrode overlaps at least a portion with its corresponding position detection electrode. The controller provides driving signals to the plurality of driving electrodes and corrects the press detection signals obtained from each press detection electrode using position detection signals obtained from the position detection electrodes.

[0063] According to the first configuration of the touch panel system, both the position of the indicator and the intensity of the pressure applied to the indicator can be detected using an electrostatic capacitive method without the use of thermoelectric elements. Furthermore, the touch panel system achieves high-precision operation by correcting the pressure detection signal based on the position detection signal detected by the position detection electrode, suppressing the effects of the environment and heat from the indicator.

[0064] The second configuration of the touch panel system can also be in the first configuration, where the controller includes a driving unit, a charge detection unit, and a correction unit. The driving unit generates a driving signal, the charge detection unit generates a position detection signal and a press detection signal based on the position detection electrode and the press detection electrode, and the correction unit corrects the press detection signal based on the position detection signal and generates a corrected press detection signal.

[0065] The third configuration of the touch panel system can also be in the second configuration, where the correction unit amplifies the position detection signal and subtracts the amplified position detection signal from the press detection signal to generate a corrected press detection signal.

[0066] The fourth configuration of the touch panel system can also be in the third configuration, where the controller further includes a signal processing unit that receives position detection signals and corrected press detection signals from the calibration unit and generates two-dimensional position detection information and press detection information.

[0067] The fifth configuration of the touch panel system can also include, in the first to fourth configurations, a plurality of shielding electrodes located on the first substrate. A plurality of position detection electrodes, a plurality of press detection electrodes, and a plurality of shielding electrodes extend in the column direction, and the plurality of position detection electrodes and press detection electrodes are alternately arranged in the row direction. The plurality of shielding electrodes are disposed between the press detection electrodes and the position detection electrodes. By having shielding electrodes, direct capacitive coupling between the position detection electrodes and the driving electrodes can be suppressed, and the detection of capacitance changes caused by the touch panel being pressed by an indicator electrode can be suppressed.

[0068] The sixth configuration of the touch panel system may also be in the first to fifth configurations, wherein the first substrate and the second substrate have a first main surface and a second main surface located on the opposite side of the first main surface, and the first dielectric layer is located between the second main surface of the first substrate and the first main surface of the second substrate.

[0069] The seventh configuration of the touch panel system may also include, in the sixth configuration, the touch panel further comprising: a cover layer located on the first main surface side of the first substrate; and a second dielectric layer located between the cover layer and the first substrate.

[0070] The eighth configuration of the touch panel system can also be such that, in the seventh configuration, the first dielectric layer and the second dielectric layer are made of the same material. This allows for more accurate suppression of the thermal effects in the press detection signal.

[0071] The touch panel system in the ninth configuration can also be configured such that, in the seventh configuration, the first dielectric layer is made of a first material, and the second dielectric layer is made of a second material. The second material is different from the first material, and in both the second and first materials, the relative permittivity changes with temperature in the same direction. This allows for more accurate suppression of the thermal effects in the press detection signal.

[0072] The tenth configuration of the touch panel system can also be such that, in the ninth configuration, the second material has a larger elastic modulus than the first material. This allows for more accurate detection of loads based on the indicator.

[0073] The eleventh configuration of the touch panel system can also include, in the first to sixth configurations, a third dielectric layer located between the first dielectric layer and the second substrate. The first dielectric layer is made of a first material, and the third dielectric layer is made of a third material. The third material differs from the first material in that the relative permittivity of the first and third materials changes with temperature in opposite directions. This allows for more accurate suppression of the thermal effects in the press detection signal.

[0074] The twelfth configuration of the touch panel system can also be in the configuration of the sixth to ninth, in which multiple driving electrodes and multiple floating island electrodes are located on the second main surface of the first substrate, and multiple press detection electrodes and multiple position detection electrodes are located on the first main surface of the second substrate.

[0075] The thirteenth configuration of the touch panel system can also be in the configurations of the sixth to ninth, in which multiple driving electrodes and multiple floating island electrodes are located on the second main surface of the first substrate, and multiple press detection electrodes and multiple position detection electrodes are located on the second main surface of the second substrate.

[0076] The fourteenth configuration of the touch panel system can also be in the configuration of the sixth to the ninth, in which multiple driving electrodes and multiple floating island electrodes are located on the first main surface of the first substrate, and multiple press detection electrodes and multiple position detection electrodes are located on the first main surface of the second substrate.

[0077] The display device according to the fifteenth configuration includes one of the touch panel systems from the first to fourth configurations and a display for displaying images, with the touch panel disposed on the display surface of the display. According to the display device according to the fifteenth configuration, a display device is realized that can suppress the effects of heat and perform high-precision detection even under various ambient temperatures by touching the surface of the touch panel display device with an indicator.

[0078] In the sixteenth configuration of the control method for a touch panel, the touch panel is an electrostatic capacitive touch panel and includes: a first substrate and a second substrate; a first dielectric layer located between the first substrate and the second substrate; a plurality of driving electrodes located on the first substrate; a plurality of floating island electrodes located on the first substrate; a plurality of press detection electrodes located on the second substrate; and a plurality of position detection electrodes located on the second substrate. When viewed from above, each driving electrode overlaps with at least a portion of its corresponding press detection electrode, and each floating island electrode overlaps with at least a portion of its corresponding position detection electrode. A driving signal is provided to the plurality of driving electrodes, and a press detection signal obtained from each press detection electrode is corrected using a position detection signal obtained from the position detection electrode.

[0079] According to the control method of the touch panel in the sixteenth configuration, both the position of the indicator and the intensity of the pressure applied to the indicator can be detected using an electrostatic capacitive method without the use of thermoelectric elements. Furthermore, by correcting the pressure detection signal based on the position detection signal detected by the position detection electrode, the touch panel can be controlled with high precision, suppressing the thermal effects of the usage environment or the indicator. Industrial availability

[0080] The touch panel, touch panel system, and touch panel control method disclosed herein can be used for touch panels of various applications, and are suitable for use in smartphones, tablet terminals, car dashboards, car navigation systems, etc. Explanation of reference numerals in the attached figures

[0081] 10…First substrate; 10a, 20a…First main surface; 10b, 20b…Second main surface; 11…Floating island electrode; 12…Drive electrode; 12c, 21c, 22c, 23c…Base; 12d, 21d, 22d, 23d…Connecting portion; 12e…Slit; 20…Second substrate; 21…Position detection electrode; 22…Press detection electrode; 23…Shielding electrode; 31…First dielectric layer; 32…Second dielectric layer; 33…Third dielectric layer; 40…Cover layer; 50…Adhesive layer; 51…Driver; 52…Charge detection unit; 53…ADC; 54…Correction unit; 55…Signal processing unit; 101~105…Touch panel; 201…Controller; 301…Touch panel system; 401…Display device; 410…Display; 410a…Display surface.

Claims

1. A touch panel system, characterized in that, It possesses: Electrostatic capacitive touch panel; and The controller controls the touch panel. The touch panel has: First substrate and second substrate; A first dielectric layer is located between the first substrate and the second substrate; Multiple driving electrodes are located on the first substrate; Multiple floating island electrodes are located on the first substrate; Multiple pressure detection electrodes are located on the second substrate; as well as Multiple position detection electrodes are located on the second substrate. When viewed from above, each driving electrode overlaps at least a portion with its corresponding press detection electrode, and each of the floating island electrodes overlaps at least a portion with its corresponding position detection electrode. The controller includes a drive unit, a charge detection unit, and a correction unit. The driving unit generates a driving signal and provides the driving signal to the plurality of driving electrodes. The charge detection unit generates a position detection signal and a pressure detection signal based on the position detection electrode and the pressure detection electrode. The correction unit amplifies the position detection signal and subtracts the amplified position detection signal from the press detection signal to generate a corrected press detection signal.

2. The touch panel system according to claim 1, characterized in that, The controller also includes a signal processing unit. The signal processing unit receives the position detection signal and the corrected press detection signal from the correction unit, and generates two-dimensional position detection information and press detection information.

3. A touch panel system, characterized in that, It possesses: electrostatic capacitive touch panel; and The controller controls the touch panel. The touch panel has: First substrate and second substrate; A first dielectric layer is located between the first substrate and the second substrate; Multiple driving electrodes are located on the first substrate; Multiple floating island electrodes are located on the first substrate; Multiple pressure detection electrodes are located on the second substrate; Multiple position detection electrodes are located on the second substrate; as well as Multiple shielding electrodes are located on the first substrate. When viewed from above, each driving electrode overlaps at least a portion with its corresponding press detection electrode, and each of the floating island electrodes overlaps at least a portion with its corresponding position detection electrode. The plurality of position detection electrodes, the plurality of pressure detection electrodes, and the plurality of shielding electrodes extend in the column direction, respectively. The plurality of position detection electrodes and the plurality of press detection electrodes are alternately arranged in the row direction. The plurality of shielding electrodes are disposed between the pressure detection electrode and the position detection electrode. The controller provides drive signals to the plurality of drive electrodes and uses the position detection signals obtained from the position detection electrodes to correct the pressure detection signals obtained from each pressure detection electrode.

4. The touch panel system according to any one of claims 1 to 3, characterized in that, The first substrate and the second substrate each have a first main surface and a second main surface located on the opposite side of the first main surface. The first dielectric layer is located between the second main surface of the first substrate and the first main surface of the second substrate.

5. The touch panel system according to claim 4, characterized in that, The touch panel also features: A cover layer, located on the first main surface side of the first substrate; and A second dielectric layer is located between the cover layer and the first substrate.

6. The touch panel system according to claim 5, characterized in that, The first dielectric layer and the second dielectric layer are made of the same material.

7. The touch panel system according to claim 5, characterized in that, The first dielectric layer is made of a first material. The second dielectric layer is made of a second material. The second material is different from the first material. In both the second and first materials, the relative permittivity changes with temperature in the same way.

8. The touch panel system according to claim 7, characterized in that, The second material has a larger elastic modulus than the first material.

9. The touch panel system according to any one of claims 1 to 3, characterized in that: The touch panel also includes a third dielectric layer, which is located between the first dielectric layer and the second substrate. The first dielectric layer is made of a first material. The third dielectric layer is made of a third material. The third material differs from the first material in that the relative permittivity changes with temperature in opposite directions in both materials.

10. The touch panel system according to claim 4, characterized in that, The plurality of driving electrodes and the plurality of floating island electrodes are located on the second main surface of the first substrate. The plurality of pressure detection electrodes and the plurality of position detection electrodes are located on the first main surface of the second substrate.

11. The touch panel system according to claim 4, characterized in that, The plurality of driving electrodes and the plurality of floating island electrodes are located on the second main surface of the first substrate. The plurality of pressure detection electrodes and the plurality of position detection electrodes are located on the second main surface of the second substrate.

12. The touch panel system according to claim 4, characterized in that, The plurality of driving electrodes and the plurality of floating island electrodes are located on the first main surface of the first substrate. The plurality of pressure detection electrodes and the plurality of position detection electrodes are located on the first main surface of the second substrate.

13. A display device, characterized in that, It possesses: The touch panel system according to any one of claims 1 to 12; and A monitor that displays images. The touch panel is disposed on the display surface of the display.

14. A control method for a touch panel, characterized in that, The touch panel is an electrostatic capacitive touch panel and has the following features: First substrate and second substrate; A first dielectric layer is located between the first substrate and the second substrate; Multiple driving electrodes are located on the first substrate; Multiple floating island electrodes are located on the first substrate; Multiple pressure detection electrodes are located on the second substrate; Multiple position detection electrodes are located on the second substrate; as well as Multiple shielding electrodes are located on the first substrate. When viewed from above, each driving electrode overlaps at least a portion with its corresponding press detection electrode, and each of the floating island electrodes overlaps at least a portion with its corresponding position detection electrode. The plurality of position detection electrodes, the plurality of pressure detection electrodes, and the plurality of shielding electrodes extend in the column direction, respectively. The plurality of position detection electrodes and the plurality of press detection electrodes are alternately arranged in the row direction. The plurality of shielding electrodes are disposed between the pressure detection electrode and the position detection electrode. A drive signal is provided to the plurality of drive electrodes, and the press detection signal obtained from each press detection electrode is corrected using the position detection signal obtained from the position detection electrode.

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