JP2013008231A - Touch panel with pressure detection function capable of corresponding to both electrostatic capacitance system and resistance film system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch panel comprising a pressure detection function which suppresses thickness and is capable of suppressing variation in sensitivity.SOLUTION: On a lower surface of an upper transparent substrate, a plurality of upper transparent electrodes are provided in a striped manner and on an upper surface of a lower transparent substrate, a plurality of lower transparent electrodes are provided in a striped manner across the upper transparent electrodes. A gap forming member is provided in an area where the upper transparent substrate and the lower transparent substrate are opposed, in such a manner as to form a gap between the upper transparent electrodes and the lower transparent electrodes. A transparent pressure-sensitive ink member is provided to cover at least either the upper transparent electrodes or the lower transparent electrodes. When external force is applied in a thickness direction of the upper transparent substrate, the transparent pressure-sensitive ink member is brought into contact with both the upper transparent electrodes and the lower transparent electrodes to conduct the both.

Description

  The present invention relates to a touch panel having a pressure detection function for measuring a pressure of a directional component perpendicular to a surface among external forces applied to the surface.

  In recent years, in an electronic device having a touch panel, particularly a portable electronic device such as a mobile phone or a portable game machine, it is required to add a press detection function to the touch panel, for example, instead of a determination button. Here, the pressure detection function refers to a function for measuring the pressure of external force applied to a certain surface (also referred to as pressure). An example of a touch panel having a press detection function is disclosed in Patent Document 1 (Japanese Patent No. 4642158). Hereinafter, a touch panel having a press detection function is referred to as a touch input device.

  FIG. 13 is a cross-sectional view showing a state where the touch input device of Patent Document 1 is attached to an electronic apparatus. As shown in FIG. 13, the touch input device of Patent Document 1 includes a touch panel body 101 and a pressure-sensitive sensor 102 attached to the lower surface of the touch panel body 101 with an adhesive 103. The pressure-sensitive sensor 102 is formed in a frame shape and is bonded to a frame portion 105a of the housing 105 that is positioned around the display unit 104 of the electronic device.

  FIG. 14 is an exploded perspective view of the pressure-sensitive sensor 102. As shown in FIGS. 13 and 14, the pressure-sensitive sensor 102 includes an upper film 121 and a lower film 122 disposed to face the lower surface of the upper film 121. An upper electrode 121 a is disposed on the lower surface of the upper film 121. A lower electrode 122 a is disposed on the upper surface of the lower film 122.

  In the corner portion of the upper film 121, a dot-shaped upper pressure-sensitive ink member 123a is disposed so as to cover the upper electrode 121a. In the corner portion of the lower film 122, a dot-shaped lower pressure-sensitive ink member 123b is disposed so as to cover the lower electrode 122a and face the upper pressure-sensitive ink member 123a. A gap holding member 124 is disposed in a region where the upper film 121 and the lower film 122 are opposed to each other. The gap holding member 124 has adhesiveness to bond the upper film 121 and the lower film 122, and holds the gap 131 between the opposing surfaces of the upper pressure-sensitive ink member 123a and the lower pressure-sensitive ink member 123b. This is an insulating member. A through hole 124 a is provided in a corner portion of the gap holding member 124. Upper and lower pressure-sensitive ink members 123a and 123b are disposed in the through hole 124a.

Japanese Patent No. 4642158

  In the touch input device of Patent Document 1 having the above configuration, since the touch panel body 101 and the pressure-sensitive sensor 102 are stacked in series in the thickness direction, there is a problem that the thickness of the touch input device is large. In addition, since the pressure-sensitive sensor 102 is formed in a frame shape, the sensitivity of the pressure-sensitive sensor 102 differs between when the center portion of the touch panel body 101 is pressed and when the peripheral edge portion of the touch panel body 101 is pressed. That is, there is a problem that the sensitivity of the pressure-sensitive sensor 102 varies depending on the pressed position.

  In recent years, it has been required to increase the area of the display unit 104 of the electronic device. In order to increase the area of the display unit 104, it is considered effective to reduce the width dimension of the frame portion 105a of the pressure sensor 102 and the housing 105. However, reducing the width dimension of the pressure sensor 102 leads to an increase in the sensitivity variation. For this reason, there is a limit to reducing the width dimension of the pressure-sensitive sensor 102.

  Further, in the conventional pressure-sensitive sensor 102, the upper film 121, the upper electrode 121a, the upper pressure-sensitive ink member 123a, and the lower film 122, the lower electrode 122b, and the lower pressure-sensitive ink member 123b are bonded via the gap holding member 124. It has a structure. A through hole 124 a is formed in the gap holding member 124 so that the upper pressure-sensitive ink member 123 a and the lower pressure-sensitive ink member 123 b come into contact with each other when the pressure sensor 102 is pressed. Of course, the upper film 122, the upper electrode 121a, and the upper pressure-sensitive ink member 123a are not bonded to the lower film 122, the lower electrode 122b, and the lower pressure-sensitive ink member 123b in the portion where the through hole 124a is formed. Therefore, there exists a problem that the upper film 121 and the lower film 122 are easy to peel off.

  Accordingly, an object of the present invention is to provide a touch panel having a press detection function capable of suppressing the thickness and suppressing the variation in sensitivity.

In order to achieve the above object, the present invention is configured as follows.
According to the first aspect of the present invention, an upper transparent substrate;
A plurality of upper transparent electrodes arranged in stripes on the lower surface of the upper transparent substrate;
A lower transparent substrate disposed opposite to the lower surface of the upper transparent substrate;
A plurality of lower transparent electrodes arranged in a stripe shape in a direction intersecting the plurality of upper transparent electrodes on the upper surface of the lower transparent electrode,
The upper transparent substrate and the lower transparent substrate are disposed in opposing regions, and have adhesiveness to bond the upper transparent substrate and the lower transparent substrate, and the plurality of upper transparent electrodes and the plurality of lower transparent substrates A gap forming member that forms a gap with the electrode;
A conductive transparent pressure-sensitive ink member that is provided so as to cover at least one of the plurality of upper transparent electrodes or the plurality of lower transparent electrodes, and whose electrical characteristics are changed by an applied pressing force;
With
When the upper transparent substrate is deformed by applying an external force in the thickness direction of the upper transparent substrate, the transparent pressure-sensitive ink member is in contact with both the upper transparent electrode and the lower transparent electrode to make them conductive. Provided is a touch panel having a detection function.

  According to the second aspect of the present invention, there is provided the touch panel having the pressure detection function according to the first aspect, wherein the transparent pressure-sensitive ink member is provided so as to cover only the plurality of lower transparent electrodes.

  According to a third aspect of the present invention, there is provided a touch panel having a pressure detection function according to the first or second aspect, wherein the gap is filled with an insulating transparent liquid.

  According to the 4th aspect of this invention, the refractive index of the said transparent liquid provides the touch panel which has a press detection function as described in a 3rd aspect higher than the refractive index of air.

  According to the 5th aspect of this invention, the kinematic viscosity in 25 degreeC of the said transparent liquid provides the touch panel which has a press detection function as described in the 3rd or 4th aspect lower than 500,000 mm2 / S.

  According to a sixth aspect of the present invention, there is provided the touch panel having a pressure detection function according to any one of the third to fifth aspects, wherein the heat resistance range of the transparent liquid is −45 ° C. to 125 ° C. To do.

  According to a seventh aspect of the present invention, there is provided a touch panel having a press detection function according to any one of the first to sixth aspects, wherein a transparent conductive film is formed on the upper surface of the upper transparent electrode. .

According to an eighth aspect of the present invention, a detection circuit connected to each of the plurality of upper transparent electrodes and the plurality of lower transparent electrodes for detecting a position where the upper transparent substrate is pressed;
A plurality of switches for connecting and separating each of the plurality of upper transparent electrodes and the plurality of lower transparent electrodes and the detection circuit;
A controller that controls on / off of the plurality of switches for each of a predetermined number of adjacent switches;
A touch panel having a pressure detection function according to any one of the first to seventh aspects is provided.

  A conventional touch panel having a pressure detection function is manufactured under the idea that a touch panel body and a pressure sensor are separately manufactured and then combined. For this reason, a plurality of substrates for supporting each electrode of the touch panel body and each electrode of the pressure-sensitive sensor and a plurality of adhesive layers for bonding these substrates are required, and the thickness increases.

  On the other hand, according to the touch panel having a pressure detection function according to the present invention, the upper transparent electrode and the lower transparent electrode necessary for exerting the function of the touch panel on the two substrates of the upper transparent substrate and the lower transparent substrate, A pressure-sensitive ink member necessary for exhibiting the function of the pressure-sensitive sensor is provided. Thereby, thickness can be suppressed significantly.

  Further, according to the touch panel having a pressure detection function according to the present invention, the transparent pressure-sensitive ink member is not provided in a frame shape, but is provided so as to cover at least one of the plurality of upper transparent electrodes or the plurality of lower transparent electrodes. ing. That is, the transparent pressure-sensitive ink member is provided on substantially the whole of the plurality of upper transparent substrates or the plurality of lower transparent substrates. Thereby, variation in sensitivity can be suppressed. In addition, since the transparent pressure-sensitive ink member is used as the pressure-sensitive ink member, it is possible to suppress a decrease in transmittance (visibility of the display unit) due to the pressure-sensitive ink member. Moreover, since it is not necessary to provide a through-hole in the gap forming member as in Patent Document 1, the adhesion between the upper transparent substrate and the lower transparent substrate can be improved.

1 is a perspective view of a mobile phone equipped with a touch input device according to a first embodiment of the present invention. It is a schematic cross section of the A1-A1 line | wire of FIG. In the touch input device of FIG. 1, it is a schematic cross section which shows a state when pressing force is applied to the input surface of the upper transparent substrate. It is a schematic cross section which shows the 1st modification of the touch input device concerning 1st Embodiment of this invention. It is a schematic cross section which shows the 2nd modification of the touch input device concerning 1st Embodiment of this invention. It is explanatory drawing which shows typically the state with which several upper transparent electrodes were each connected via the switch, and several lower transparent electrodes were each connected via the switch. It is a schematic cross section of the touch input device concerning a 2nd embodiment of the present invention. FIG. 8 is a schematic cross-sectional view showing a state when a pressing force is applied to the input surface of the upper transparent substrate in the touch input device of FIG. 7. It is a schematic cross section of the touch input device concerning a 3rd embodiment of the present invention. It is a top view which shows the 1st formation pattern of the transparent conductive film formed in the upper surface of an upper transparent electrode. It is a top view which shows the 2nd formation pattern of the transparent conductive film formed in the upper surface of an upper transparent electrode. It is a top view which shows the 3rd formation pattern of the transparent conductive film formed in the upper surface of an upper transparent electrode. It is sectional drawing which shows the state which attached the conventional touch input device to the electronic device. It is a disassembled perspective view of the pressure sensor with which the conventional touch input device is provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all of the following drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

<< First Embodiment >>
The touch input device according to the first embodiment of the present invention suitably functions as, for example, a touch input device for a display of an electronic device, particularly a portable electronic device such as a mobile phone or a game machine. In the first embodiment, an example in which a touch input device is mounted on a mobile phone will be described.

  FIG. 1 is a perspective view of a mobile phone equipped with a touch input device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line A1-A1 of FIG.

  As shown in FIGS. 1 and 2, the cellular phone 1 includes a synthetic resin-made substantially rectangular parallelepiped housing 2 having a rectangular display window 2A formed on the front surface, and a rectangular display unit 3A such as a liquid crystal or an organic EL. And a display device 3 built in the housing 2, a touch input device 4 fitted in the display window 2 </ b> A, and a plurality of input keys 5 arranged on the front surface of the housing 2.

  The display window 2 </ b> A of the housing 2 is formed to have a step to allow the touch input device 4 to be fitted. A rectangular opening 2a is formed on the bottom surface of the display window 2A so that the display 3A of the display device 3 can be seen. The touch input device 4 is stuck on the rectangular frame-shaped frame portion 2b around the opening 2a with an adhesive (not shown) to close the opening 2a.

  Note that the shape or size of the display window 2 </ b> A can be variously changed according to the shape or size of the touch input device 4. The level difference of the display window 2A can be variously changed according to the thickness of the touch input device 4 and the like. The shape or size of the opening 2a of the display window 2A can be variously changed according to the shape or size of the display 3A. In the first embodiment, as an example, the display window 2A, the opening 2a, the display unit 3A, and the touch input device 4 have a rectangular shape, and the surface of the housing 2 and the surface of the touch input device 4 have the same height. The step of the display window 2A is set so that

  The touch input device 4 detects a plane coordinate (XY coordinate) as an operation position based on a touch operation on the input surface of the touch input device 4 and is applied in a direction (Z direction) orthogonal to the input surface. It is configured to detect the strength of the pressing force.

  Specifically, the touch panel input device 4 includes an upper transparent substrate 11 serving as an input surface and a lower transparent substrate 12 serving as a portion bonded to the frame portion 2 b of the housing 2. On the lower surface of the upper transparent substrate 11, a plurality of upper transparent electrodes 11a are arranged in a stripe shape. On the upper surface of the lower transparent substrate 12, a plurality of lower transparent electrodes 12a are arranged in a stripe shape in a direction intersecting (preferably a direction orthogonal to) the plurality of upper transparent electrodes 11a. In the first embodiment, as an example, the plurality of upper transparent electrodes 11a are formed in a stripe shape in the X-axis direction, and the plurality of lower transparent electrodes 12a are formed in a stripe shape in the Y-axis direction. The upper transparent electrode 11a and the lower transparent electrode 12a are not limited to a linear shape, and may be, for example, a wave shape or a shape whose thickness changes midway. In addition, the plurality of upper transparent electrodes 11a and the plurality of lower transparent electrodes 12a are connected to a routing circuit having a predetermined pattern for energizing the outside such as a bus bar or a routing destination, although not shown.

  On the plurality of lower transparent electrodes 12a, a transparent pressure-sensitive ink member 13 having conductivity is disposed so as to cover the plurality of lower transparent electrodes 12a. That is, the transparent pressure-sensitive ink 13 is provided on substantially the entire plurality of lower transparent electrodes 12a. The transparent pressure-sensitive ink member 13 has a property that its electrical characteristics change depending on the applied pressing force. A gap forming member 14 is arranged in a facing region between the upper transparent substrate 11 and the lower transparent substrate 12. The gap forming member 14 has an adhesive property to bond the upper transparent substrate 11 and the lower transparent substrate 12 and to form gaps 21 between the plurality of upper transparent electrodes 12a and the pressure sensitive sensors 13. It is a sex member. The gap forming member 14 is formed in a frame shape so as to include the plurality of upper transparent electrodes 11a, the plurality of lower transparent electrodes 12a, and the pressure-sensitive ink member 13 when the touch input device 4 is viewed from the thickness direction. .

  When a conductor such as a user's finger is brought closer from above the upper transparent substrate 11 shown in FIG. 2, the distance between the upper transparent electrode 11a and the conductor changes, and this occurs between the upper transparent electrode 11a and the conductor. Capacitance to change. Further, the capacitance generated between the lower transparent electrode 12a and the conductor changes as the distance between the lower transparent electrode 12a and the conductor changes. By detecting these changes in capacitance, the position of the conductor (XY coordinates) in plan view can be detected.

  FIG. 3 shows a state of the touch input device 4 when the pressing force P is applied to the input surface of the upper transparent substrate 11. As shown in FIG. 3, when a pressing force P is applied to the input surface of the upper transparent substrate 11 by a conductor such as a finger, the upper transparent substrate 11 is deformed by bending or the like. As a result, at least the transparent pressure-sensitive ink member 13a closest to the portion to which the pressing force P is applied comes into contact with both the upper transparent electrode 11a and the lower transparent electrode 12a, and both are conducted. The transparent pressure-sensitive ink member 13 changes in electrical characteristics (resistance value) due to a change in clamping force received from the upper and lower transparent electrodes 11a and 12a. By measuring the voltage value between the electrode 11a and the lower transparent electrode 12a, the strength of the pressing force P applied in the direction orthogonal to the input surface (Z direction) can be detected.

  On the other hand, when a non-conductor such as a pen is approached from above the upper transparent substrate 11 shown in FIG. 2, the capacitance between the non-conductor and the upper transparent electrode 11a and the non-conductor and the lower transparent electrode 12a The capacitance between them does not change. Therefore, the position of the nonconductor and the pressing force P due to the nonconductor are detected as follows.

  That is, when the pressing force P is applied as shown in FIG. 3 by a non-conductor such as a pen, as described above, the transparent pressure-sensitive ink member 13a closest to the portion to which the pressing force P is applied is the upper transparent electrode. Both 11a and the lower transparent electrode 12a come into contact with each other to conduct. At this time, by detecting which of the plurality of upper transparent electrodes 11a and the plurality of lower transparent electrodes 12a the upper transparent electrode 11a and the lower transparent electrode 12a are conductive, the plane coordinates (XY coordinates) serving as the operation position are obtained. Can be detected. Further, as described above, by measuring the voltage value between the upper transparent electrode 11a and the lower transparent electrode 12a that are conducted through the transparent pressure-sensitive ink member 13, in the direction orthogonal to the input surface (Z direction). The strength of the applied pressing force P can be detected.

  In addition, when the upper transparent substrate 11 is bent downward with a conductor or a nonconductor, the distance between the upper transparent electrode 11a and the lower transparent electrode 12a changes, so that it occurs between the upper transparent electrode 11a and the lower transparent electrode 12a. Capacitance to change. Based on this change in capacitance, it is also possible to detect the plane coordinates (XY coordinates) serving as the operation position.

  The thickness dimension of the upper and lower transparent substrates 11 and 12 is set to 25 μm to 100 μm, for example. As the material of the upper and lower transparent substrates 11 and 12, it is preferable to use a material excellent in transparency, rigidity, and workability. For example, as the material of the upper transparent substrate 11, glass, polymethyl methacrylate (PMMA) resin, polycarbonate (PC) resin, or the like can be used. Further, as materials for the upper and lower transparent substrates 11 and 12, materials usable for flexible substrates, such as polyethylene terephthalate, polystyrene resin, polyolefin resin, ABS resin, AS resin, acrylic resin, AN resin, etc. General-purpose resin can be used. Furthermore, as materials for the upper and lower transparent substrates 11 and 12, general-purpose engineering resins such as polystyrene resin, polycarbonate resin, polyacetal resin, polycarbonate-modified polyphenylene ether resin, polybutylene terephthalate resin, or ultrahigh molecular weight polyethylene resin, Alternatively, a super engineering resin such as a polysulfone resin, a polyphenylene sulfide resin, a polyphenylene oxide resin, a polyarylate resin, a polyetherimide resin, a polyimide resin, a liquid crystal polyester resin, or a polyallyl heat-resistant resin can also be used.

  The thickness dimension of the upper and lower transparent electrodes 11a and 12a is set to 50 to 2000 mm, for example. The upper and lower transparent electrodes 11a and 12a are made of a transparent conductive film. Examples of the material for the transparent conductive film include metal oxides such as tin oxide, indium oxide, antimony oxide, zinc oxide, cadmium oxide, and ITO, or silver nanowires, carbon nanotubes, and conductive polymer thin films. . As a method for forming the upper and lower transparent electrodes 11a and 12a, for example, a conductive film is formed on the entire surface of each transparent substrate 11 and 12 by using, for example, vacuum deposition, sputtering, ion plating, CVD, or roll coater. There is a method in which unnecessary portions are removed by etching after forming the film. The etching can be performed by forming a resist on a portion to be left as an electrode by a photolithography method or a screen method, and then immersing in an etching solution such as hydrochloric acid. In addition, after the formation of the resist, the etching is performed by spraying an etchant to remove a portion of the conductive film where the resist is not formed, and then immersing in a solvent to swell or dissolve the resist and remove it. Can also be done. The upper and lower transparent electrodes 11a and 12a can also be formed by a laser.

  The thickness dimension of the transparent pressure-sensitive ink member 13 (height from the lower transparent substrate 12) is larger than the thickness dimension of the lower transparent electrode 12a, and is set to 1 μm to 10 μm, for example. The composition constituting the transparent pressure-sensitive ink member 13 is made of a conductive material whose electric characteristics such as an electric resistance value change according to an external force. More specifically, the transparent pressure-sensitive ink member 13 includes a plurality of adjacent pressure-sensitive particles, which are conductive particles contained in the composition in a large number as the pressure is applied. Regardless of the presence or absence of direct contact between pressure-sensitive particles, a tunnel current flows and changes from an insulating state to an energized state. As the composition, for example, Quantum Tunneling Composite available under the trade name “QTC Clear” from Peratec Ltd. of Darlington, England can be used. In addition, by using the quantum tunnel phenomenon composite material, the transparent pressure-sensitive ink member 13 can change the resistance value in accordance with the applied force. The transparent pressure-sensitive ink member 13 can be disposed on the lower transparent substrate 12 by application. As a method for applying the transparent pressure-sensitive ink member 13, a printing method such as screen printing, offset printing, gravure printing, or flexographic printing can be used.

  The thickness dimension of the gap holding member 14 is set to 2 to 300 μm, for example. Examples of the gap forming member 14 include a double-sided adhesive tape in which an adhesive such as an acrylic adhesive paste is formed on both surfaces of a core material such as a polyethylene terephthalate film, a UV curable adhesive, a thermosetting adhesive, and moisture. A curable adhesive or an anaerobic curable adhesive can be used.

  As described above, according to the touch input device according to the first embodiment, the upper transparent electrode 11a and the lower transparent electrode 12a, which are necessary for exhibiting the function of the touch panel, are provided on the upper transparent substrate 11 and the lower transparent substrate 12. And a transparent pressure-sensitive ink member 13 necessary for exhibiting the function of the pressure-sensitive sensor. Thereby, compared with the conventional touch input device, thickness can be suppressed significantly.

  Further, according to the touch input device according to the first embodiment, the transparent pressure-sensitive ink member 13 is not provided in a frame shape, but is provided so as to cover the plurality of lower transparent electrodes 12a. That is, the transparent pressure-sensitive ink member 13 is provided on substantially the entire lower transparent substrate 12a. Thereby, variation in sensitivity can be suppressed. Moreover, since the transparent pressure-sensitive ink member 13 is used as the pressure-sensitive ink member, it is possible to suppress a decrease in transmittance (visibility of the display unit 3A) due to the pressure-sensitive ink member. Moreover, since it is not necessary to provide a through hole in the gap forming member 14 as in Patent Document 1, the adhesion between the upper transparent substrate 11 and the lower transparent substrate 12 can be improved.

  Further, according to the touch input device according to the first embodiment, the width dimension of the frame portion 2b of the housing 2 can be reduced without depending on the width dimension of the transparent pressure-sensitive ink member 13, so that the display is performed. The area of the portion 3A can be increased.

  In addition, the touch input device according to the first embodiment can be used as a resistive touch panel, a capacitive touch panel, or a touch panel compatible with both systems.

  The present invention is not limited to the first embodiment, and can be implemented in various other modes. For example, in the first embodiment, as shown in FIG. 2, the transparent pressure-sensitive ink member 13 is formed on each of the plurality of lower transparent electrodes 12a, but the present invention is not limited to this. For example, as shown in FIG. 4, a plurality of lower transparent electrodes 12 a may be covered with one transparent pressure-sensitive ink member 13.

  In the first embodiment, the transparent pressure-sensitive ink member 13 is formed only on the plurality of lower transparent electrodes 12a. However, the present invention is not limited to this. For example, as shown in FIG. 5, both the plurality of upper transparent electrodes 11 a and the plurality of lower transparent electrodes 12 a may be covered with a transparent pressure-sensitive ink member 13. Alternatively, the transparent pressure-sensitive ink member 13 may be formed only on the plurality of upper transparent electrodes 11a. That is, at least one of the plurality of upper transparent electrodes 11a and the plurality of lower transparent electrodes 12a may be covered with the transparent pressure-sensitive ink member 13. When the pressing force P is applied to the upper transparent substrate 11, the upper transparent substrate 11 usually has a larger deformation amount (deflection amount) than the lower transparent substrate 12. Due to the difference in deformation, the transparent pressure-sensitive ink member 13 provided on the upper transparent electrode 11a is more likely to deteriorate than the transparent pressure-sensitive ink member 13 provided on the lower transparent electrode 12a. Therefore, when the transparent pressure-sensitive ink member 13 is provided on any one of the plurality of upper transparent electrodes 11a and the plurality of lower transparent electrodes 12a, it is preferable to provide the transparent pressure-sensitive ink member 13 on the plurality of lower transparent electrodes 12a. .

  In the first embodiment, the upper transparent substrate 11 is used as the input surface and the upper transparent substrate 11 is directly pressed. However, the present invention is not limited to this. For example, another transparent substrate such as a protective panel may be provided on the upper surface of the upper transparent substrate 11 so that the upper transparent substrate 11 is indirectly pressed. In this case, since the upper transparent substrate 11 is not exposed to the outside, it is possible to eliminate the necessity of using a material having excellent surface abrasion resistance as the material of the upper transparent substrate 11. The protective panel is a film or plate material for protecting the upper transparent substrate 11 and has scratch resistance and antifouling properties. The thickness dimension of the protection panel is, for example, 0.25 to 3.00 mm. For example, an organic-inorganic hybrid material can be used as the protective panel. Moreover, you may provide the decorating layer which decorates the touchscreen of this invention on the upper surface of the upper transparent substrate 11. FIG.

  In the first embodiment, the lower surface of the lower transparent substrate 12 is directly bonded to the frame portion 2b of the housing 2. However, the present invention is not limited to this. For example, another transparent substrate may be provided on the lower surface of the lower transparent substrate 12 so that the lower transparent substrate 12 is indirectly bonded to the frame portion 2 b of the housing 2. Moreover, it is preferable that a transparent electrode for electromagnetic shielding that serves as a so-called electromagnetic shield that shields interference electromagnetic waves (AC noise) generated from the display device 3 is provided on the lower surface of the lower transparent substrate 12. The transparent electrode for electromagnetic shielding may be provided on the other transparent substrate.

  Next, an example of a method for detecting the pressed position of the touch input device 4 according to the first embodiment will be described with reference to FIG. FIG. 6 is an explanatory diagram schematically showing a state in which a plurality of upper transparent electrodes are connected via switches and a plurality of lower transparent electrodes are connected via switches.

Here, for convenience of explanation, the plurality of upper transparent electrodes 11 a are configured by _eight upper transparent electrodes 11 a _{1 to} 11 a ₈ . The plurality of lower transparent electrode 12a is assumed to be composed of eight lower transparent electrode _12a 1 _{~12a 8.} The touch input device 4 is used as a capacitive touch panel.

As shown in FIG. 6, the upper transparent electrodes 11 a _{1 to} 11 a ₈ and the lower transparent electrodes 12 a _{1 to} 12 a ₈ are connected to a detection circuit 6 for detecting a position where the upper transparent substrate 11 is pressed. Each of the upper transparent electrodes 11a _{1 to} 11a ₈ and the detection circuit 6 are connected and separated by switches S1 to S8. Further, each of the lower transparent electrodes 12a _{1 to} 12a ₈ and the detection circuit 6 are contacted and separated by switches S11 to S18. The switches S <b> 1 to S <b> 8 and the switches S <b> 11 to S <b> 18 are controlled on and off by the control unit 7.

  For example, the control unit 7 controls on / off of the switches S1 to S8 and the switches S11 to S18 as follows.

First, the control unit 7 turns on only the switch S1 among the switches S1 to S8. Thus, detecting the electrostatic capacitance detection circuit 6 is generated between the upper transparent electrode 11a ₁ and the finger.
Next, the control unit 7 turns off the switch S1 and turns on the switch S2. Thus, detecting the electrostatic capacitance detection circuit 6 is generated between the upper transparent electrode 11a ₂ and the finger.
Next, the control unit 7 turns off the switch S2 and turns on the switch S3. Thus, detecting the electrostatic capacitance detection circuit 6 is generated between the upper transparent electrode 11a ₃ and the finger.
Similarly, the control unit 7 repeats the control of turning on one switch and turning off the other switches from the switches S1 to S8, and the detection circuit 6 is connected to the upper transparent electrode connected to the turned on switch and the finger. Capacitance generated between and is sequentially detected.

In synchronization with the on / off control of the switches S1 to S8 or after the on / off control, the control unit 7 turns on only the switch S11 among the switches S11 to S18. Thus, detecting the electrostatic capacitance detection circuit 6 is generated between the lower transparent electrode 12a ₁ and the finger.
Next, the control unit 7 turns off the switch S11 and turns on the switch S12. Thus, detecting the electrostatic capacitance detection circuit 6 is generated between the lower transparent electrode 12a ₂ and the finger.
Next, the control unit 7 turns off the switch S12 and turns on the switch S13. Thus, the detection circuit 6 detects the electrostatic capacitance generated between the lower transparent electrode 12a ₃ and the finger.
Similarly, the control unit 7 repeats the control of turning on one switch and turning off the other switches from the switches S11 to S18, and the detection circuit 6 is connected to the upper transparent electrode connected to the turned on switch and the finger. Capacitance generated between and is sequentially detected.

For example, when the approaching finger of a user at the intersection B1 between the upper transparent electrode 11a ₃ and the lower transparent electrode 12a _3, the detection value of each of the electrostatic capacitance generated between the upper transparent electrode 11a _{1 to 8} and the finger home,
Detection values of the electrostatic capacitance generated between the upper transparent electrode 11a ₃ and the finger is largest. In addition, among the detection values of the capacitances generated between the lower transparent electrodes 12a ₁ to ₈ and the finger, the detection values of the capacitance generated between the lower transparent electrode 12a ₃ and the finger are the largest. . Therefore, the position where the finger approaches can be specified based on these largest detection values.

  As described above, the touch input device 4 according to the first embodiment can be used as a resistive touch panel or a capacitive touch panel. For example, the touch input device 4 can be applied to a resistive digital touch panel, a mutual capacitive touch panel, a self capacitive touch panel, and the like. In general, a resistance film type digital touch panel has a narrower electrode width (wiring width) than a mutual type capacitive touch panel, and thus there is a concern about a decrease in sensitivity. In resistive digital touch panels, the electrode widths of the upper and lower electrodes are often the same. However, in the mutual capacitive touch panel, the electrode width may be different between the transmitting side and the receiving side. Many (to prevent sensitivity loss due to mutual interference). In addition, the self-type capacitive touch panel has a narrow electrode width and cannot secure sufficient sensitivity. Furthermore, when the upper electrode and the lower electrode are in contact with each other in the electrostatic detection state, there is a possibility that the capacitance cannot be detected.

  Therefore, it is preferable that the control unit 7 controls on / off of the switches S1 to S8 and the switches S11 to S18 as follows, for example.

First, the control unit 7 simultaneously turns on the switches S1 and S2 (two adjacent switches) among the switches S1 to S8. Thereby, the detection circuit 6 detects the electrostatic capacitance generated between the upper transparent electrodes 11a ₁ and 11a ₂ and the finger.
Next, the control unit 7 turns off the switches S1 and S2 and turns on the switches S3 and S4. Thereby, the detection circuit 6 detects the electrostatic capacitance generated between the upper transparent electrodes 11a ₃ and 11a ₄ and the finger.
Similarly, the control unit 7 repeats the control to turn on the two adjacent switches and turn off the other switches from the switches S1 to S8, and the detection circuit 6 has two switches connected to the turned on switches. The capacitance generated between the upper transparent electrode and the finger is sequentially detected.

In synchronization with the on / off control of the switches S1 to S8 or after the on / off control, the control unit 7 turns on the switches S11 and S12 (two switches adjacent to each other) among the switches S11 to S18. Thereby, the detection circuit 6 detects the electrostatic capacitance generated between the lower transparent electrodes 12a ₁ and 12a ₂ and the finger.
Next, the control unit 7 turns off the switches S11 and S12 and turns on the switches S13 and S14. Thus, detecting the electrostatic capacitance detection circuit 6 is generated between the lower transparent electrode 12a _3, 12a ₄ and the finger.
Similarly, the control unit 7 repeats the control of turning on the two adjacent switches and turning off the other switches from the switches S11 to S18, and the detection circuit 6 is connected to the two switches that are turned on. The electrostatic capacitance generated between the lower transparent electrode and the finger is sequentially detected.

For example, when the approaching finger of a user at the intersection B1 between the upper transparent electrode 11a ₃ and the lower transparent electrode 12a _3, the detection value of each of the electrostatic capacitance generated between the upper transparent electrode 11a _{1 to 8} and the finger home,
The detection value of the capacitance generated between the upper transparent electrodes 11a ₃ and 11a ₄ and the finger becomes the largest. Of the detected capacitance values generated between the lower transparent electrodes 12a ₁ to ₈ and the finger, the detected capacitance values generated between the lower transparent electrodes 12a ₃ and 12a ₄ and the finger are as follows. Become the largest. Therefore, the position where the finger approaches can be specified based on these largest detection values.

  By performing control to turn on two adjacent switches synchronously as described above, the electrode width can be doubled. Thereby, even when the electrode widths of the upper transparent electrode 11 and the lower transparent electrode 12 are narrow, the electrode width can be apparently increased to improve the sensitivity. In the above description, the control for turning on two adjacent switches in synchronization is performed. However, the control for turning on three or more switches adjacent to each other in synchronization may be performed. Thereby, the sensitivity can be arbitrarily changed.

  In the above description, all of the switches S1 to S8 and the switches S11 to S18 are turned on in order. However, for example, the switches S1, S3, S5, and S7 are turned on in this order to reduce the number of switches that are turned on. Also good. In other words, the switches to be turned on may be thinned out within a range where the detection resolution does not decrease. As a result, the electrode width can be apparently reduced, and a decrease in detection speed can be prevented.

  In the above description, the switches S1 to S8 are turned on in the order of the switches S1, S2 → switches S3, S4 → switches S5, S6..., But the switches S1, S2 → switches S2, S3 → switch S3. You may make it turn on in order of S4 .... When the switches S1, S2, S3, S4, S5, S6,... Are turned on in this order, the resolution is halved compared to when the switches S1 to S8 are turned on one by one. This reduction in resolution is particularly noticeable when control is performed to turn on three or more adjacent switches synchronously. The switches S1, S2, S2, S3, S3, S4, etc. are turned on in this order, that is, by partially overlapping the switches that are turned on, it is possible to improve the sensitivity and reduce the decrease in resolution. become. In the above description, the on / off control of the switches S1 to S8 has been described, but the same applies to the switches S11 to S18.

<< Second Embodiment >>
FIG. 7 is a schematic cross-sectional view of a touch input device according to a second embodiment of the present invention. The touch input device 4A according to the second embodiment is different from the touch input device 4 according to the first embodiment in that the gap 21 is filled with a transparent liquid 41 having an insulating property.

  In the touch input device 4 of the first embodiment, air exists in the gap 21. Since air is transparent, the overall transmittance of the touch input device 4 is high. However, depending on the angle at which the touch input device 4 is viewed, light may be reflected due to the air present in the gap 21 and the transmittance may be reduced.

  On the other hand, according to the touch input device 4A according to the second embodiment, by filling the gap 21 with the transparent liquid 41 having an insulating property, reflection of light can be suppressed and a decrease in transmittance can be suppressed. it can. In addition, since the liquid usually has a dielectric constant higher than that of air, the sensitivity can be improved by filling the gap 21 with the transparent liquid 41 having insulating properties.

  When the gap 21 is filled with the transparent liquid 41, it is necessary to increase the sealing degree of the gap 21 so that the transparent liquid 41 does not leak out. For this reason, as shown in FIG. 8, even when the pressing force P is applied to the touch input device 4A and the upper transparent substrate 11 or the like is deformed, the gap forming member 14 is not changed so that the volume of the gap 21 does not change. Is preferably configured to be elastically deformable.

  As the transparent liquid 41, it is preferable to use a silicone-based, fluorine-based, hydrocarbon-based or alcohol-based inert liquid. Examples of this type of transparent liquid include Florinate (registered trademark), Novec (registered trademark) manufactured by 3M, silicone oil manufactured by Shin-Etsu Chemical (trade names “KF” and “HIVAC”), and hydrocarbon-based optics. Examples thereof include oil and alcohol-based polyethylene glycol.

  The refractive index of the transparent liquid 41 is preferably higher than air, that is, higher than 1.0. Thereby, generation | occurrence | production of a Newton ring can be suppressed, an optical characteristic transmittance | permeability can be improved, and the visibility of 3 A of display parts can be improved. The refractive index of the transparent liquid 41 is more preferably in the range of ± 0.5 of the refractive index of the upper transparent substrate 11. Thereby, generation | occurrence | production of a Newton ring can be suppressed further, an optical characteristic transmittance | permeability can be improved further, and the visibility of 3 A of display parts can be improved further.

On the other hand, if the kinematic viscosity of the transparent liquid 41 is too high, the upper transparent electrode 11a and the transparent pressure-sensitive ink member 13 are difficult to contact when the touch input device 4A is pressed. For this reason, it is preferable that the kinematic viscosity at 25 ° C. of the transparent liquid 41 is lower than 500,000 mm ² / S. The kinematic viscosity at 25 ° C. of the transparent liquid 41 is more preferably lower than 50,000 mm ² / S. As a result, the upper transparent electrode 11a and the transparent pressure-sensitive ink member 13 can be more easily brought into contact with each other, and can be easily returned to the original state after the contact. Further, when the kinematic viscosity at 25 ° C. of the transparent liquid 41 is low, the touch input device 4A is moved in the vertical direction when the members (eg, the upper transparent substrate 11 and the lower transparent substrate 12) that seal the transparent liquid 41 have low rigidity. When placed, it may not be possible to maintain insulation. For this reason, the kinematic viscosity at 25 ° C. of the transparent liquid 41 is preferably 0.65 mm ² / S.

  Further, it is preferable to use a transparent liquid 41 having a heat resistance range of −45 ° C. to 125 ° C. As a result, the transparent liquid 41 does not harden or become loose due to a normal use environment, and a stable input value can be obtained when using the touch input device 4A (reproducibility (accuracy) can be increased).

<< Third Embodiment >>
FIG. 9 is a schematic cross-sectional view of a touch input device according to a third embodiment of the present invention. The touch input device 4B according to the third embodiment is different from the touch input device 4A according to the second embodiment in that a transparent conductive film 51 is formed on the upper surface of the upper transparent electrode 11.

  The transparent conductive film 51 is formed to function as an antenna of a mobile phone, for example. Thereby, when attaching the touch input device 4B to a mobile phone etc., the trouble of attaching an antenna separately can be saved.

  When the touch input device 4B is used as a capacitive touch panel, when the transparent conductive film 51 is formed in the region VA where the upper transparent electrode 11a and the lower transparent electrode 12a are formed, the transparent conductive film 51 Detection of the capacitance generated between the finger and the upper transparent electrode 11a or the lower transparent electrode 12a is hindered. For this reason, when the touch input device 4B is used as a capacitive touch panel, it is preferable to form a transparent conductive film 51A in a region outside the region VA as shown in FIG. On the other hand, when the touch input device 4B is used as a resistive film type touch panel, the above problem does not occur. That is, the position detection of the resistive film type is performed by detecting whether or not the upper transparent electrode 11a and the lower transparent electrode 12a are electrically connected, and thus occurs between the finger and the upper transparent electrode 11a or the lower transparent electrode 12a. There is no need to detect the electrostatic capacitance. For this reason, as shown in FIG. 11 or FIG. 12, the transparent conductive films 51B and 51C can be formed so as to cross the region VA.

  It is to be noted that, by appropriately combining any of the various embodiments, the effects possessed by them can be produced.

  Having the pressing function according to the present invention can suppress thickness and suppress variations in sensitivity. Therefore, PDAs, portable terminals such as handy terminals, OA devices such as copiers, facsimiles, smartphones, mobile phones, mobile phones It is useful for electronic devices such as game devices, electronic dictionaries, car navigation systems, small PCs, and various home appliances.

DESCRIPTION OF SYMBOLS 1 Cellular phone 2 Case 2A Display window 3 Display 3A Display unit 4 Touch input device 5 Input key 6 Detection circuit 7 Control unit 11 Upper transparent substrate 11a Upper transparent electrode 12 Lower transparent substrate 12a Lower transparent electrode 13 Transparent pressure sensitive ink member 14 Gap Forming Member 21 Gap 31 Switch 41 Transparent Liquid 51 Transparent Conductive Film

Claims (8)

An upper transparent substrate;
A plurality of upper transparent electrodes arranged in stripes on the lower surface of the upper transparent substrate;
A lower transparent substrate disposed opposite to the lower surface of the upper transparent substrate;
A plurality of lower transparent electrodes arranged in a stripe shape in a direction intersecting the plurality of upper transparent electrodes on the upper surface of the lower transparent electrode,
The upper transparent substrate and the lower transparent substrate are disposed in opposing regions, and have adhesiveness to bond the upper transparent substrate and the lower transparent substrate, and the plurality of upper transparent electrodes and the plurality of lower transparent substrates A gap forming member that forms a gap with the electrode;
A conductive transparent pressure-sensitive ink member that is provided so as to cover at least one of the plurality of upper transparent electrodes or the plurality of lower transparent electrodes, and whose electrical characteristics are changed by an applied pressing force;
With
When the upper transparent substrate is deformed by applying an external force in the thickness direction of the upper transparent substrate, the transparent pressure-sensitive ink member is in contact with both the upper transparent electrode and the lower transparent electrode to make them conductive. Touch panel with detection function.   The touch panel having a pressure detection function according to claim 1, wherein the transparent pressure-sensitive ink member is provided so as to cover only the plurality of lower transparent electrodes.   The touch panel having a press detection function according to claim 1, wherein the gap is filled with an insulating transparent liquid.   The touch panel having a press detection function according to claim 3, wherein a refractive index of the transparent liquid is higher than a refractive index of air.   The touch panel having a press detection function according to claim 3 or 4, wherein a kinematic viscosity at 25 ° C of the transparent liquid is lower than 500,000 mm2 / S.   The touch panel having a press detection function according to any one of claims 3 to 5, wherein the heat resistance range of the transparent liquid is -45 ° C to 125 ° C.   The touch panel which has a press detection function as described in any one of Claims 1-6 in which the transparent conductive film is formed in the upper surface of the said upper transparent electrode. A detection circuit connected to each of the plurality of upper transparent electrodes and the plurality of lower transparent electrodes for detecting a position where the upper transparent substrate is pressed;
A plurality of switches for connecting and separating each of the plurality of upper transparent electrodes and the plurality of lower transparent electrodes and the detection circuit;
A controller that controls on / off of the plurality of switches for each of a predetermined number of adjacent switches;
The touch panel which has a press detection function of any one of Claims 1-7 provided with.

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