Tactile display touch panel and display device

Abstract

In a tactile presentation touch panel that detects a position touched by a finger or pen and presents a tactile sensation, position detection sensitivity is ensured and a tactile presentation function is improved. The panel comprises: a detection electrode; a first dielectric layer covering the detection electrode; a tactile electrode arranged so as not to overlap with the detection electrode when viewed from above; and a second dielectric layer covering the tactile electrode, the relative dielectric constant of the second dielectric layer being increased compared to the relative dielectric constant of the first dielectric layer. Thus, even if the tactile presentation intensity is increased, the propagation of noise can be suppressed and the position detection sensitivity can be ensured.

Description

Technical Field

[0001] The present invention relates to a tactile presentation touch panel that detects a position touched by a finger, a pen, or the like and presents a tactile sense, and a display device including the tactile presentation touch panel. Background Art

[0002] Touch panels that detect the touched position when a user touches a screen are widely known. Among them, there is also a growing demand for tactile touch panels that present a sense of touch such as hand feeling. For example, a technology is disclosed that presents a sense of touch through an electrostatic capacitance generated between a tactile electrode and a user's touch on the surface of a tactile touch panel (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-058153 Summary of the invention

[0006] However, in conventional tactile sense presenting touch panels, when, for example, electrostatic capacitance is increased to enhance the tactile sense presented by the tactile electrodes, there is a problem that the propagation of noise increases and position detection becomes difficult.

[0007] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a tactile sense presenting touch panel and a display device which can suppress the propagation of noise even when the tactile sense presenting intensity is increased and can ensure the position detection sensitivity.

[0008] The tactile sense presenting touch panel according to the present invention comprises: a transparent insulating substrate; a plurality of detection electrodes formed on the transparent insulating substrate, extending in a first direction, and arranged in a second direction different from the first direction; a first dielectric layer covering the detection electrodes; a plurality of tactile electrodes formed on the surface of the transparent insulating substrate on which the detection electrodes are formed or on the first dielectric layer, extending in the first direction, and arranged in a second direction so as not to overlap with the detection electrodes when viewed from above, and to which a voltage signal for presenting tactile sense is applied; a second dielectric layer covering the tactile electrodes and having a relative dielectric constant larger than that of the first dielectric layer; and a transmitting electrode arranged on the side opposite to the surface of the transparent insulating substrate on which the detection electrodes are formed, and used together with the detection electrodes to detect a touch position.

[0009] Furthermore, the display device according to the present invention includes: the tactile sense presenting touch panel according to the present invention; and a display panel disposed on the opposite side of the surface of the tactile sense presenting touch panel on which the tactile electrodes are formed, and displaying at least one of an image and a video.

[0010] According to the present invention, by increasing the relative dielectric constant of the second dielectric layer covering the tactile electrodes compared to the relative dielectric constant of the first dielectric layer covering the detection electrodes, noise propagation can be suppressed even if the tactile presentation intensity is increased, thereby ensuring position detection sensitivity and improving the tactile presentation function. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is an exploded perspective view schematically showing the display device according to Embodiment 1 of the present invention.

[0012] Figure 2 It is a schematic cross-sectional view of a display device according to Embodiment 1 of the present invention.

[0013] Figure 3 It is a plan view showing the detection electrodes and the tactile electrodes according to the first embodiment of the present invention.

[0014] Figure 4 This is a plan view showing a transmitting electrode according to Embodiment 1 of the present invention.

[0015] Figure 5 This is a schematic diagram regarding formation of electrostatic capacitance between a tactile electrode and a pointer according to the first embodiment of the present invention.

[0016] Figure 6 This is a perspective view regarding formation of electrostatic capacitance between a tactile electrode and a pointer according to the first embodiment of the present invention.

[0017] Figure 7 This is a diagram showing an example of a voltage signal of a first frequency applied to a first tactile electrode according to the first embodiment of the present invention.

[0018] Figure 8 This is a diagram showing an example of a voltage signal of the second frequency applied to the second tactile electrode according to the first embodiment of the present invention.

[0019] Fig. 9 This is a diagram showing an example of a voltage signal obtained by combining a voltage signal of a first frequency and a voltage signal of a second frequency according to the first embodiment of the present invention.

[0020] Fig.10 This is a diagram showing a position detection sensitivity ratio and a tactile sense presentation intensity ratio of the tactile sense presenting touch panel according to the first embodiment of the present invention.

[0021] Fig.11 This is a diagram schematically showing electric conduction according to Embodiment 1 of the present invention.

[0022] Fig.12: is a relationship diagram showing the relationship between the SN ratio and the relative dielectric constant ratio in position detection according to the first embodiment of the present invention.

[0023] Fig.13 It is a schematic cross-sectional view of a tactile sense presenting touch panel according to Embodiment 1 of the present invention.

[0024] Fig.14 It is an exploded perspective view schematically showing the display device according to Embodiment 1 of the present invention.

[0025] Fig.15 It is a schematic cross-sectional view of a display device according to Embodiment 1 of the present invention.

[0026] Fig.16 It is a schematic cross-sectional view of a tactile sense presenting touch panel according to Embodiment 2 of the present invention.

[0027] Fig.17 It is a plan view showing detection electrodes and tactile electrodes according to Embodiment 3 of the present invention.

[0028] Fig.18 It is a diagram showing the SN ratio and the tactile sense presentation intensity ratio of position detection of the tactile sense presenting touch panel according to the third embodiment of the present invention.

[0029] Fig.19 This is a diagram schematically showing electric conduction according to Embodiment 3 of the present invention.

[0030] Fig. 20 : is a relationship diagram showing the relationship between the SN ratio of position detection and the ratio of the electrode widths according to the third embodiment of the present invention.

[0031] (Explanation of symbols)

[0032] 1: indicator; 2: virtual finger; 10: touch detection circuit; 20: voltage supply circuit; 21: first voltage generating circuit; 22: second voltage generating circuit; 30: transmitting electrode substrate; 31: insulating layer; 32: transmitting electrode; 33: substrate; 34: wiring for transmitting electrode; 35, 44: terminal portion; 40: detection electrode substrate; 41: first dielectric layer; 42: detection electrode; 43: transparent insulating substrate; 45: extraction wiring; 50: tactile presentation layer; 51: second dielectric layer; 52: tactile electrode; 53: first tactile electrode; 54: second tactile electrode; 55: through hole; 101: tactile presentation touch panel; 111, 112: adhesive material; 200: display panel; 201: drive circuit; 301: display device. DETAILED DESCRIPTION

[0033] Implementation method 1.

[0034] Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings.

[0035] Figure 1 1 is an exploded perspective view schematically showing the tactile sense presenting touch panel 101 and the display device 301 in Embodiment 1. Figure 2 : is a cross-sectional view schematically showing the display device 301. The x-axis and the y-axis are orthogonal to each other and are parallel to the plane of the tactile presentation touch panel 101. In the embodiment, the long side direction of the tactile presentation touch panel 101 is set as the x-axis, and the short side direction is set as the y-axis. The z-axis represents a direction perpendicular to the plane of the tactile presentation touch panel 101. In the embodiment, the positive direction of the z-axis is set as the operation surface side, and the negative direction is set as the display panel 200 side.

[0036] The display device 301 includes: a display panel 200 such as a liquid crystal having a display function; and a tactile presentation touch panel 101 having a touch screen on the upper surface of the display panel 200 ( Figure 1 The touch screen 110 is installed via an adhesive material 111 or the like (in the positive direction of the Z axis), detects the position touched by an indicator 1 such as a user's finger or a pen, and presents a tactile sensation to the indicator 1.

[0037] The display panel 200 is, for example, a liquid crystal panel. It may also be an organic EL (Electro-Luminescence) panel, an electronic paper panel, etc. In addition, the display panel 200 is connected to the drive circuit 201 and is driven by an electrical signal supplied from the drive circuit 201 to display.

[0038] The tactile presentation touch panel 101 comprises: a detection electrode substrate 40, in which a detection electrode 42 covered with a first dielectric layer 41 is formed on a transparent insulating substrate 43; a tactile presentation layer 50, formed on the first dielectric layer 41, having a tactile electrode 52 covered with a second dielectric layer 51; and a transmitting electrode substrate 30, which is installed on the lower surface of the transparent insulating substrate 43, for example, via an adhesive material 112, and in which a transmitting electrode 32 covered with an insulating layer 31 is formed on a substrate 33 such as a glass substrate.

[0039] In addition, the transmitting electrode 32 and the detecting electrode 42 are Figure 2 The touch detection circuit 10 shown is connected to detect the position touched by the indicator 1. In addition, the tactile electrode 52 of the tactile presentation layer 50 is connected to the voltage supply circuit 20, and the electrostatic capacitance that changes corresponding to the voltage supplied from the voltage supply circuit 20 presents a tactile sensation to the indicator 1 that touches the tactile presentation touch panel 101.

[0040] Hereinafter, the detection electrode substrate 40 , the tactile sense presenting layer 50 , and the transmission electrode substrate 30 included in the tactile sense presenting touch panel 101 will be described separately.

[0041] The detection electrode substrate 40 comprises: a transparent insulating substrate 43, which is made of, for example, glass, polycarbonate, or PET (Polyethylene Terephthalate), and is transparent and insulating; a plurality of detection electrodes 42, which are formed on the transparent insulating substrate 43; and a first dielectric layer 41, which covers the detection electrodes 42. The detection electrodes 42 are arranged in a first direction ( Figure 2 ) along the y-axis direction, and along the second direction ( Figure 2 The two electrodes are arranged parallel to each other with intervals (in the x-axis direction).

[0042] The tactile presentation layer 50 on the detection electrode substrate 40 includes a plurality of tactile electrodes 52 and a second dielectric layer 51 covering the tactile electrodes 52. The tactile electrodes 52 are arranged in the first direction ( Figure 2 ) along the y-axis direction, and along the second direction ( Figure 2 The detection electrodes 42 and the touch electrodes 52 are arranged in parallel with each other at intervals (in the x-axis direction). The widths of the detection electrodes 42 and the touch electrodes 52 are about 5 to 50 μm, respectively, and are formed in stripes. Figure 1 , Figure 2 In the example of FIG. 1 , the detection electrode and the tactile electrode are formed to have the same width.

[0043] In this example, the detection electrode 42 and the tactile electrode 52 are Figure 2 The tactile electrodes 52 are arranged alternately in the x-axis direction. Figure 2 The term "non-overlapping" here means that the position detection by the detection electrodes 42 and the tactile presentation by the tactile electrodes 52 do not interfere with each other, and is not limited to that all the detection electrodes 42 and the tactile presentation do not overlap at all. Thus, the position detection and the tactile presentation do not interfere with each other, and the sensitivity of the position detection can be ensured and the tactile presentation function can be improved.

[0044] Furthermore, the first dielectric layer 41 on the detection electrode 42 is, for example, a silicon dioxide (SiO2) film having a thickness of about 0.5 μm and a relative dielectric constant of 3.5, and the second dielectric layer 51 on the touch electrode 52 is, for example, a tantalum oxide (Ta2O5) film having a thickness of about 0.3 μm and a relative dielectric constant of 18.2, and the relative dielectric constant of the second dielectric layer 51 on the touch electrode 52 is increased compared to the relative dielectric constant of the first dielectric layer 41 on the detection electrode 42. Thus, the electrostatic capacitance between the touch electrode 52 and the indicator 1 can be increased to increase the tactile sensation presented, and the propagation of noise to the detection electrode 42 can be suppressed. Therefore, the position detection sensitivity can be ensured and the tactile sensation presentation function can be improved.

[0045] The thickness of the first dielectric layer 41 and the second dielectric layer 51 is preferably 0.2 μm or more and 1 μm or less. Therefore, if the thickness is ensured, insufficient mechanical strength and discharge from the electrodes can be suppressed. The reduction in light transmittance and detection sensitivity caused by excessive thickness can be suppressed.

[0046] Next, use Figure 3 , describing the wiring of the detection electrode 42 and the tactile electrode 52. The detection electrode 42 and the tactile electrode 52 can be formed, for example, by indium tin oxide (ITO) having light transmittance. By using a light transmittance material, the detection electrode 42 and the tactile electrode 52 are made transparent so as not to hinder the visual recognition of the image, picture, etc. displayed on the display panel 200. In addition, the detection electrode 42 and the tactile electrode 52 can be formed into a mesh by making fine wiring that is thin enough not to hinder visual recognition. For example, the fine wiring can be formed of silver, copper, aluminum, or alloys thereof.

[0047] The detection electrodes 42 and the tactile electrodes 52 are preferably arranged at an equal pitch P of about 20 to 200 μm. With such an arrangement, reflection of external light on the transparent insulating substrate 43 is averaged, thereby ensuring visibility of images and pictures displayed on the display panel 200 .

[0048] A terminal portion 44 exposed from the second dielectric layer 51 is provided at an end portion of the transparent insulating substrate 43 , and a plurality of extraction wirings 45 connected to the respective electrodes are provided on the transparent insulating substrate 43 .

[0049] exist Figure 3 In the example of FIG. 5 , the tactile electrodes 52 are sequentially set as the first tactile electrodes 53 and the second tactile electrodes 54, and different voltage signals are applied to each of them to present tactile sensation. The tactile electrodes 52 are connected to the extraction wiring 45 through the through hole 55, and are connected to the terminal portion 44 via the extraction wiring 45. Here, the detection electrode 42 is arranged between the first tactile electrode 53 and the second tactile electrode 54 so as not to overlap when viewed from above.

[0050] The extraction wiring 45 connected to the detection electrode 42 and the tactile electrode 52 is connected to the terminal portion 44, and the terminal portion 44 is connected to the touch detection circuit 10 and the voltage supply circuit 20 via, for example, an FPC (Flexible Print Circuit). Here, the touch detection circuit 10 is a circuit that detects changes in electrostatic capacitance and has an IC (Integrated Circuit) for detection and a microcomputer.

[0051] The extraction wiring 45 is composed of, for example, a plurality of wirings Lc(1) to Lc(j) and a plurality of wirings Ld(1) to Ld(j). Here, an arbitrary integer numbered from 1 to j is denoted as k, and the wirings Lc(k) and Ld(k) are connected to the kth tactile electrode 52 and the kth detection electrode 42, respectively.

[0052] In addition, the extraction wiring 45 is formed by a metal film or a laminated film of a metal film and a non-metal film. In the case where the laminated film is a plurality of layers including a lower layer and an upper layer, the upper layer functions as a protective layer for the lower layer. For example, in an etching process, as a protective layer, the upper layer protects the lower layer from corrosion agents. In addition, during the manufacture and use of the display device 301, the upper layer functions as a cap layer to prevent corrosion of the lower layer. Furthermore, if a material having better adhesion to the transparent insulating substrate 43 than the material of the upper layer is used in the material of the lower layer, it is possible to suppress the peeling of the extraction wiring 45.

[0053] In this example, the wirings Lc(1) to Lc(j) and the wirings Ld(1) to Ld(j) are arranged outside the area where the tactile presentation touch panel 101 can present tactile sensations, and extend sequentially from the wirings arranged near the center of the terminal portion 44 in a manner that allows for approximately the shortest distance from the terminal portion 44 to the corresponding detection electrode 42 and tactile electrode 52. The terminal portion 44 is arranged along the long side of the transparent insulating substrate 43 near the center of the long side. The wirings Lc(1) to Lc(j) and the wirings Ld(1) to Ld(j) ensure insulation from each other and are arranged as densely as possible. When the extraction wiring 45 is arranged in this way, the area of ​​the transparent insulating substrate 43 where the detection electrode 42 and the tactile electrode 52 are not arranged can be suppressed, thereby expanding the area where position detection and tactile presentation can be performed.

[0054] Next, use Figure 4 , the transmission electrode substrate 30 is described. The transmission electrode substrate 30 includes a transmission electrode 32 formed on a substrate 33 and an insulating layer 31 covering the transmission electrode 32.

[0055] A terminal portion 35 is provided at an end portion of the substrate 33, and the transmission electrode 32 is connected to the terminal portion 35 via a plurality of transmission electrode wirings 34. The terminal portion 35 is connected to the touch detection circuit 10 via, for example, an FPC.

[0056] The plurality of transmitting electrodes 32 are Figure 4 Extending in the x-axis direction, along Figure 4 In this example, the transmitting electrode 32 is arranged in parallel with the detecting electrode 42 in a plan view, thereby being able to detect the position touched by the indicator 1 through two coordinate axes. By connecting the detecting electrode substrate 40 and the transmitting electrode substrate 30 to the touch detection circuit 10 in this way, the position touched by the indicator 1 is detected. Figure 4 In the example of FIG. 1 , the width of the transmitting electrode 32 is larger than the width of the detecting electrode 42, but the width of the transmitting electrode 32 may be the same as the width of the detecting electrode 42. In addition, similarly to the detecting electrode 42, the transmitting electrode 32 may be formed by meshing fine wiring that is thin enough not to hinder visual recognition.

[0057] Mutual capacitance is formed at the intersection of each of the transmitting electrode 32 and the detecting electrode 42, and the mutual capacitance changes near the position touched by the indicator 1. Voltage pulses are sequentially input to the plurality of transmitting electrodes 32, and as the mutual capacitance changes, the current flowing from the transmitting electrode 32 to the detecting electrode 42 changes, so by detecting the current change with the touch detection circuit 10, the position coordinates can be calculated.

[0058] Next, use Figures 5 to 9 , which explains the formation of electrostatic capacitance between the tactile electrode 52 and the indicator 1 and the application of the voltage signal. Figure 5 The upper figure shows a cross-sectional schematic diagram, and the lower figure shows a top view. Figure 5 , Figure 6 As shown, when the pointer 1 touches the surface of the tactile sense presenting touch panel 101 , an electrostatic capacitance is formed in the second dielectric layer 51 between the pointer 1 and the tactile electrode 52 .

[0059] The tactile presentation voltage generating circuit (not shown) of the voltage supply circuit 20 includes a first voltage generating circuit 21 and a second voltage generating circuit 22. The first voltage generating circuit 21 applies a voltage signal Va to the plurality of first tactile electrodes 53. In addition, the second voltage generating circuit 22 applies a voltage signal Vb to the plurality of second tactile electrodes 54. Here, Va and Vb may be applied to all or part of the plurality of first tactile electrodes 53 and the second tactile electrodes 54.

[0060] Figure 7 is a diagram showing an example of a voltage signal Va, Figure 8 is a diagram showing an example of a voltage signal Vb. The voltage signal Va of the first voltage generating circuit 21 has a first frequency, and the voltage signal Vb of the second voltage generating circuit 22 has a second frequency different from the first frequency. The amplitude of the voltage signal Va and the amplitude of the voltage signal Vb may also be the same amplitude VL. Figure 7 , Figure 8 In the example, sine waves with different frequencies are used as the voltage signal Va and the voltage signal Vb. Instead of the sine wave, a pulse wave or an example with other waveforms may be used. In order to generate a sufficient tactile sensation, the amplitude VL is preferably several tens of volts.

[0061] Fig. 9: is a diagram showing an amplitude modulation signal VF generated by combining a voltage signal Va and a voltage signal Vb. The voltage signal Va is applied to the first tactile electrode 53 by the first voltage generating circuit 21, and the voltage signal Vb is applied to the second tactile electrode 54 by the second voltage generating circuit 22. In the region where the electrostatic capacitance is formed between each of the first tactile electrode 53 and the second tactile electrode 54 and the indicator 1, charging and discharging under the amplitude modulation signal VF having a maximum amplitude VH substantially equal to the amplitude VL is repeated. Through this charging and discharging, the indicator 1, which is covered and contacted with the first tactile electrode 53 and the second tactile electrode 54 via the second dielectric layer 51, is applied with an electrostatic force corresponding to the amplitude modulation signal VF having a maximum amplitude VH.

[0062] The amplitude modulation signal VF has a beat frequency corresponding to the difference between the first frequency and the second frequency. When the pointer 1 moves on the tactile sense presenting touch panel 101, the friction force acting on the pointer 1 changes at the beat frequency, so that the pointer 1 vibrates at the beat frequency. The user can perceive the vibration of the pointer 1 as a tactile sense obtained from the surface of the tactile sense presenting touch panel 101.

[0063] Here, the interval I between the first tactile electrode 53 and the second tactile electrode 54 is preferably smaller than the diameter Φ of the indicator 1. When the indicator 1 is configured to contact from the first tactile electrode 53 to the second tactile electrode 54, a tactile sense can be reliably presented.

[0064] Next, use Figure 10 to Figure 11 , the relationship between the relative dielectric constant εa of the first dielectric layer 41 and the relative dielectric constant εb of the second dielectric layer 51 and the position detection sensitivity and the tactile presentation intensity is described.

[0065] The electrostatic capacitance C is represented by C=ε0•εr•S / d (ε0: dielectric constant of vacuum, εr: relative dielectric constant, S: touch area, d: film thickness). The touch area S is determined by the indicator 1, and the film thickness d is determined by product specifications such as the required mechanical strength and ESD (Electrostatic Discharge) resistance. Therefore, if the film thickness is the same, the electrostatic capacitance C is determined by the relative dielectric constant. In this embodiment, the relative dielectric constant εb of the second dielectric layer 51 covering the tactile electrode 52 is increased compared to the relative dielectric constant εa of the first dielectric layer 41 covering the detection electrode 42. As a result, the electrostatic capacitance between the tactile electrode 52 and the indicator 1 is enhanced to increase the tactile sensation presented, and the noise propagation to the detection electrode 42 is suppressed, thereby ensuring the position detection sensitivity and improving the tactile presentation function.

[0066] In order to verify the effect of making εb greater than εa, make Fig.10Samples A to C shown compare the signal-to-noise ratio (SN ratio) of position detection and the tactile presentation intensity ratio (the ratio when sample B is set to 1). Each dielectric layer is formed of, for example, silicon dioxide (SiO2) with a relative dielectric constant of 3.5 or tantalum oxide (Ta2O5) with a relative dielectric constant of 18.2, and the thickness of each dielectric layer is set to the same level.

[0067] The position detection sensitivity is represented by the SN ratio detected by the touch detection circuit 10 when one end of the virtual finger 2 (conductor with a diameter of 8 mm) imitating the user's finger is grounded and placed on the tactile presentation touch panel 101. In addition, the tactile presentation intensity is represented by the electrostatic force between the virtual finger 2 and the tactile electrode 52 calculated based on the potential difference between the amplitude modulation signal VF and the voltage signal Va and the voltage signal Vb measured by the oscilloscope without grounding one end of the virtual finger 2 and placing it on the tactile presentation touch panel 101. In addition, when calculating the SN ratio, the voltage amplitude of the pulse signal input from the touch detection circuit 10 to the transmitting electrode 32 is set to 5V, and the amplitude VL of the voltage signal Va and the voltage signal Vb is set to 100V.

[0068] exist Fig.10 It can be seen that sample C, which sets εa and εb to 18.2, can increase the tactile presentation intensity ratio compared to sample B, which sets εa and εb to 3.5, but the SN ratio of position detection decreases. On the other hand, it can be seen that sample A, which sets εa to 3.5 and εb to 18.2, has both improved SN ratio of position detection and tactile presentation intensity ratio compared to sample B.

[0069] In use Fig.11 When considering the appearance of the electric current E shown in Fig.11 In the sample B shown in (b), the electrostatic capacitance cannot be increased and the electrostatic force does not increase.

[0070] In addition, Fig.11 In sample C with large εa and εb shown in (c), the electrostatic force between the tactile electrode 52 and the virtual finger 2 increases, but the electric conduction E between the detection electrode 42 and the virtual finger 2 also increases. The grounding of the virtual finger 2 and the touch detection circuit 10 are not necessarily consistent. Usually, there are many cases where the grounding of other devices is interposed between these grounds. When the grounding of the touch detection circuit 10 is used as a reference, noise generated from other devices may be propagated to the virtual finger 2. As a result, the noise is further propagated from the virtual finger 2 to the detection electrode 42, so the SN ratio cannot be improved.

[0071] Compared with these, in sample A where εb is greater than εa, Fig.11As shown in (a), εb is large, so the electrostatic force between the tactile electrode 52 and the virtual finger 2 can be increased. Furthermore, εa is smaller than εb, so the electric conduction E between the detection electrode 42 and the virtual finger 2 is hardly increased, and the propagation of noise can be suppressed.

[0072] In addition, the position detection signal depends on the amount of electrical conduction between the transmitting electrode 32 and the detecting electrode 42 blocked by the virtual finger 2. Sample A has a larger εb than sample B, and the electrical conduction is easily pulled toward the direction of the virtual finger 2. As a result, the amount of electrical conduction blocked by the virtual finger 2 can be increased, the position detection signal can be increased, and the SN ratio can be improved.

[0073] In this way, when the relative dielectric constant εb of the second dielectric layer 51 is made larger than the relative dielectric constant εa of the first dielectric layer 41 , it is possible to improve the tactile sense presentation function while ensuring the position detection sensitivity.

[0074] Furthermore, if Fig.12 As shown, according to the relationship between the ratio of εa to εb, i.e., εb / εa, and the SN ratio, when εb / εa is greater than 4, the SN ratio is saturated, so the SN ratio can be stably maintained. When εb / εa is greater than 5, the SN ratio is further saturated, so the SN ratio can be more stably maintained.

[0075] εa and εb can be determined by the materials used in the first dielectric layer 41 and the second dielectric layer 51. Each dielectric layer may be formed of silicon dioxide (SiO2), tantalum pentaoxide (Ta2O5), barium titanate (BaTiO3), strontium titanate (SrTiO3), or the like.

[0076] In addition, in this embodiment, an example is described in which the second dielectric layer 51 is formed so as to cover the tactile electrode 52 and the first dielectric layer 41 is formed so as to cover the detection electrode 42. However, Fig.13 As shown in FIG. 2( a ), the second dielectric layer 51 is formed so as not to be disposed above the detection electrode 42 but only to cover the tactile electrode 52. Fig.13 (b) The detection electrode 42 and the touch electrode 52 are formed on the transparent insulating substrate 43 , the first dielectric layer 41 is formed only on the detection electrode 42 , and the second dielectric layer 51 is formed only on the upper surface of the touch electrode 52 .

[0077] In the touch detection circuit 10 of the present embodiment, the contact points connected from the touch detection circuit 10 to the detection electrode 42 and the contact points connected from the touch detection circuit 10 to the transmission electrode 32 may be exchanged. Even with this configuration, the same effects as those of the present embodiment can be obtained.

[0078] In addition, in this embodiment, an example in which the transmission electrode 32 covered with the insulating layer 31 is arranged on the substrate 33 is described, but it is also possible to Fig.14 , Fig.15 As shown, the transmitting electrode 32 is formed on the surface of the transparent insulating substrate 43 constituting the detecting electrode substrate 40 on the side where the detecting electrode 42 is not arranged, and the display panel 200 is mounted via the insulating layer 31 covering it and the adhesive material 111. Thus, the substrate 33 can be omitted and the manufacturing cost can be reduced.

[0079] In addition, in this embodiment, an example is described in which the transmitting electrode 32 and the detecting electrode 42 are crossed at right angles when viewed from above, but the crossing angle may be not a right angle but a slightly inclined direction. The length of each electrode that can be arranged can be adjusted in the direction in which it is extended and arranged, so the number of electrodes formed on each substrate can be increased.

[0080] Implementation method 2.

[0081] Fig.16 1 is a schematic cross-sectional view of a tactile presentation touch panel 101 according to Embodiment 2. The display device 301 according to Embodiment 2 includes a display panel 200 and a tactile presentation touch panel 101, similarly to Embodiment 1, and the tactile presentation touch panel 101 includes a detection electrode substrate 40, a tactile presentation layer 50, and a transmission electrode substrate 30. Embodiment 2 is different in that the first dielectric layer 41 of the detection electrode substrate 40 and the second dielectric layer 51 of the tactile presentation layer 50 are formed of a plurality of layers. The same reference numerals are assigned to the same components as those in Embodiment 1, and their descriptions are omitted.

[0082] The first dielectric layer 41 includes first dielectric single layers a1 to an from the lower layer side, which are formed of dielectrics such as SiO 2 , Ta 2 O 5 , BaTiO 3 , and SrTiO 3 .

[0083] The thicknesses of the first dielectric single layers a1 to an are ta1 to tan, and the thickness ta of the first dielectric layer 41 is set to, for example, approximately 0.5 μm.

[0084] The relative dielectric constant εa of the first dielectric layer 41 formed of a plurality of layers is obtained by the following formula (1).

[0085] [Formula 1]

[0086]

[0087] In addition, the second dielectric layer 51 similarly includes second dielectric single layers b1 to bn, which are formed of dielectrics such as SiO2, Ta2O5, BaTiO3, and SrTiO3. The thicknesses of the second dielectric single layers b1 to bn are tb1 to tbn, and the thickness tb of the second dielectric layer 51 is set to about 0.3 μm, for example.

[0088] The relative dielectric constant εb of the second dielectric layer 51 formed of a plurality of layers is similarly determined from the following formula (2).

[0089] [Formula 2]

[0090]

[0091] Even if the first dielectric layer 41 and the second dielectric layer 51 are formed into multiple layers and εb is made larger than εa, the electrostatic capacitance between the tactile electrode 52 and the indicator 1 is increased to increase the tactile sensation presented, and the noise propagation to the detection electrode 42 is suppressed, so that the position detection sensitivity can be ensured and the tactile sensation presentation strength can be improved. In addition, by forming multiple layers, the adjustment of εa and εb becomes easy.

[0092] In the present embodiment, an example in which the first dielectric layer 41 and the second dielectric layer 51 are multiple layers is described. However, either the first dielectric layer 41 or the second dielectric layer 51 may be multiple layers.

[0093] Implementation method 3.

[0094] Fig.17 1 is a top view schematically showing a tactile presentation touch panel 101 according to Embodiment 3. The display device 301 according to Embodiment 3 includes a display panel 200 and a tactile presentation touch panel 101, similarly to Embodiment 1, and the tactile presentation touch panel 101 includes a detection electrode substrate 40, a tactile presentation layer 50, and a transmission electrode substrate 30. Embodiment 3 is different in that the width of the detection electrode 42 of the detection electrode substrate 40 is smaller than the width of the tactile electrode 52 of the tactile presentation layer 50. The same reference numerals are attached to the same components as those in Embodiment 1, and their descriptions are omitted.

[0095] like Fig.17 As shown, the width of the detection electrode 42 is made smaller than the width of the tactile electrode 52. This increases the electrical conduction between the indicator 1 and the tactile electrode 52 and reduces the electrical conduction between the detection electrode 42 and the tactile electrode 52, thereby ensuring position detection sensitivity and improving tactile presentation strength.

[0096] exist Fig.18, the results of calculating the SN ratio and tactile presentation intensity ratio of position detection for sample D in which the width Wa of the detection electrode 42 is set to half the width Wb of the tactile electrode 52, εa is set to 3.5, and εb is set to 18.2, and samples A to C in which the widths of the detection electrode 42 and the tactile electrode 52 are equal.

[0097] The sample B is set to 1, and the SN ratio of position detection is calculated based on the ratio of the signal and noise detected by the touch detection circuit 10 when one end of the virtual finger 2 (conductor with a diameter of 8 mm) imitating the user's finger is grounded and placed on the tactile presentation touch panel 101. In addition, the sample B is set to 1, and the virtual finger 2 is not grounded but placed on the tactile presentation touch panel 101. The tactile presentation intensity ratio is represented by the electrostatic force between the virtual finger 2 and the tactile electrode 52 calculated based on the potential difference between the amplitude modulation signal VF and the voltage signal Va and the voltage signal Vb measured by the oscilloscope. In addition, when calculating the SN ratio of position detection, the voltage amplitude of the pulse signal input from the touch detection circuit 10 to the transmitting electrode 32 is set to 5V, and the amplitude VL of the voltage signal Va and the voltage signal Vb is set to 100V.

[0098] like Fig.18 As shown, when the relative dielectric constant εa of the first dielectric layer 41 is set to 3.5 and the relative dielectric constant εb of the second dielectric layer 51 is set to 18.2, so that the relative dielectric constant of the second dielectric layer 51 is greater than the relative dielectric constant of the first dielectric layer 41, and when the width Wa of the detection electrode 42 is made half of the width Wb of the tactile electrode 52, that is, Wb / Wa=2, the SN ratio of position detection and the tactile presentation intensity ratio can be further improved compared to sample A in which Wa and Wb are equal, that is, Wb / Wa=1.

[0099] exist Fig.19 (a) schematically shows the electrical conduction of sample A and Fig.19 (b) schematically shows the conduction of sample D, Wa is smaller than Wb, so the conduction E between the virtual finger 2 and the tactile electrode 52 increases, so the tactile presentation intensity is improved. The noise generated when the tactile electrode 52 moves can be further suppressed from propagating to the detection electrode 42, so the SN ratio is improved.

[0100] exist Fig. 20, the relationship between the SN ratio of position detection and the ratio of the width Wa of the detection electrode 42 and the width Wb of the touch electrode 52, i.e., Wb / Wa, in the sample where εa and εb are 3.5 is shown. Here, the SN ratio of position detection is a ratio in which the SN ratio of position detection of sample B, in which the widths of the detection electrode 42 and the touch electrode 52 are equal and εa and εb are 3.5, is set to 1. When Wb / Wa increases, even if Wa is smaller than Wb, the noise propagating to the detection electrode 42 can be suppressed, and the SN ratio is improved. When Wb / Wa is greater than 2, even if the width Wa of the detection electrode 42 is less than half of the width Wb of the touch electrode 52, the decrease in the electric flux density between the detection electrode 42 and the touch electrode 52 is saturated, and the increase in the SN ratio is saturated. Therefore, it is preferable to form the width of the detection electrode 42 to be less than half of the width of the touch electrode 52.

[0101] In this way, by making the width of the detection electrode 42 smaller than the width of the tactile electrode 52 , it is possible to ensure position detection sensitivity and improve the tactile sense presentation function.

[0102] In Embodiments 1 to 3, no other electrode is disposed between the electrodes in plan view, but electrically isolated floating electrodes may be disposed between the electrodes in plan view. This can average the reflection of external light and improve the visibility of images and pictures displayed on the display panel.

[0103] In addition, an example is shown in which the detection electrodes and the tactile electrodes are arranged alternately, and the detection electrodes and the tactile electrodes are the same number, but the number of electrodes may be different. In this case, the tactile electrodes and the detection electrodes do not need to be alternated, and may be arranged in the order of, for example, one tactile electrode and two or more detection electrodes. Furthermore, the shape of each electrode may not be stripe-shaped, and may be, for example, a shape formed by bending a straight line or a shape including an arc. Thus, the position detection sensitivity and tactile presentation function suitable for the application can be obtained by the number and shape of each electrode.

[0104] The embodiments disclosed in this specification can be freely combined within the scope of the embodiments, and the embodiments can be appropriately modified or omitted.

Claims

1. A tactile touch panel having an operation surface, characterized in that: The tactile presentation touch panel comprises: A transparent insulating substrate; A plurality of detection electrodes are formed on the surface of the transparent insulating substrate on the operation surface side, extend in a first direction, and are arranged in a second direction different from the first direction; a first dielectric layer covering the detection electrode and the surface of the transparent insulating substrate on the operation surface side; a plurality of tactile electrodes formed on the surface of the first dielectric layer on the operation surface side, extending in the first direction, arranged in the second direction so as not to overlap with the detection electrodes when viewed from above, and to which a voltage signal for producing a tactile sensation is applied; a second dielectric layer having a relative dielectric constant greater than that of the first dielectric layer on at least a surface of the tactile electrode on the operation surface side; as well as The transmitting electrode is arranged on the side opposite to the operation surface side of the transparent insulating substrate and is used together with the detecting electrode to detect the touch position. The detection electrode overlaps with a stack of the first dielectric layer and the second dielectric layer in a plan view. The surface of the tactile electrode on the operation surface side is covered with only the second dielectric layer of the first dielectric layer and the second dielectric layer.

2. The tactile presentation touch panel according to claim 1, characterized in that: The relative dielectric constant of the second dielectric layer is 4 times or more the relative dielectric constant of the first dielectric layer.

3. The tactile presentation touch panel according to claim 1 or 2, characterized in that: The tactile electrodes are arranged adjacent to the detection electrodes in a plan view.

4. The tactile presentation touch panel according to claim 1 or 2, characterized in that: A plurality of the tactile electrodes are arranged between the detection electrodes in a plan view.

5. The tactile presentation touch panel according to claim 1 or 2, characterized in that: further comprising a voltage supply circuit for supplying a voltage to the tactile electrode, The tactile electrode includes a first tactile electrode and a second tactile electrode to which different voltage signals are applied from the voltage supply circuit. One or more of the detection electrodes are arranged between the first tactile electrode and the second tactile electrode in a plan view.

6. The tactile sense presenting touch panel according to claim 1 or 2, characterized in that: The width of the detection electrode is smaller than the width of the tactile electrode.

7. The tactile sense presenting touch panel according to claim 6, characterized in that: The width of the detection electrode is less than or equal to half of the width of the tactile electrode.

8. The tactile sense presenting touch panel according to claim 1, 2 or 7, characterized in that: At least one of the first dielectric layer and the second dielectric layer is formed of a plurality of layers.

9. The tactile sense presenting touch panel according to claim 1, 2 or 7, characterized in that: The transmitting electrode is formed on a surface of the transparent insulating substrate opposite to a surface on which the detecting electrode is formed.

10. The tactile sense presenting touch panel according to claim 1, 2 or 7, characterized in that: The transmitting electrode is formed on a substrate. The substrate is arranged on a side of the transparent insulating substrate opposite to a surface on which the detection electrode is formed, via an insulating layer covering the transmission electrode and an adhesive material.

11. A display device, characterized in that: have: The tactile sense presenting touch panel according to any one of claims 1 to 10; and The display panel is arranged on the opposite side of the surface of the tactile sense presenting touch panel on which the tactile electrodes are formed, and displays at least one of an image and a video.

12. A tactile touch panel having an operation surface, characterized in that: The tactile presentation touch panel comprises: A transparent insulating substrate; A plurality of detection electrodes are formed on the surface of the transparent insulating substrate on the operation surface side, extend in a first direction, and are arranged in a second direction different from the first direction; a first dielectric layer covering the detection electrode and the surface of the transparent insulating substrate on the operation surface side; A plurality of tactile electrodes are formed on the surface of the transparent insulating substrate on the operation surface side, extend in the first direction, are arranged in the second direction so as not to overlap with the detection electrodes when viewed from above, and are applied with a voltage signal that produces a tactile sensation; a second dielectric layer having a relative dielectric constant greater than that of the first dielectric layer on at least a surface of the tactile electrode on the operation surface side; as well as The transmitting electrode is arranged on the side opposite to the operation surface side of the transparent insulating substrate and is used together with the detecting electrode to detect the touch position. The detection electrode overlaps the first dielectric layer and does not overlap the second dielectric layer in a plan view.

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