JP2012048472A - Touch sensor and touch pad for electronic apparatus having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch sensor that can be operated with any input medium, can detect plural operation points and can easily detect strength in a pressing direction, and to provide a touch pad for an electronic apparatus having the touch sensor.SOLUTION: The present invention relates to a touch sensor 1 that includes an insulative substrate 20 and a sheet sensor 10 placed facing the substrate 20. Plural electrode groups 21 each having plural electrodes adjacent to each other are placed on a surface facing the sheet sensor 10 of the substrate 20. The sheet sensor 10 receives a press on a side opposite to a side with the substrate 20 to come into contact with the one or plural electrode groups 21, and then makes the space between the electrodes composing the electrode groups 21 conductive.

Description

  The present invention relates to a resistive film type touch sensor and an electronic device touch pad including the touch sensor.

  2. Description of the Related Art Conventionally, touch sensors that perform input by a touch operation on a display are known. Unlike a mouse-shaped pointing device, which is a relative coordinate input method, the touch sensor can input absolute coordinates on the display, so that it is easy to operate and can be input in accordance with the operator's senses. For this reason, the touch sensor is mounted on many ticket machines such as stations, portable game devices and portable communication devices having a liquid crystal display. There are many types of touch sensors depending on the detection method, such as resistive film type, capacitance type, optical type, ultrasonic surface acoustic wave type, electromagnetic induction type, etc. Examples include a method and a capacitance method.

  An example of a resistive film type touch sensor is that a transparent conductive film made of ITO or the like is formed on each facing surface of two insulating substrates, and one transparent conductive film in which a potential gradient is formed and the other transparent conductive film are It is in a non-contact state. When pressed from one side, the one transparent conductive film and the other transparent conductive film come into contact with each other, and the absolute coordinates on the pressed surface are specified based on the voltage value detected on the other surface side. Such a resistive film type touch sensor is disclosed in Patent Document 1, for example.

  On the other hand, the capacitive touch sensor is divided into several methods such as a surface capacitive method, an inner capacitive method, and a projected capacitive method. Based on the change in capacitance between the operator's finger (corresponding to the other electrode), the absolute coordinates of the operation position are specified. Among these, the projected capacitive touch sensor has recently attracted attention, and when the operator presses two points on the operation surface with two fingers, both coordinates can be specified. A device has been devised, and an image that can be enlarged or reduced using two fingers is known. Such a capacitive touch sensor that enables multi-touch is disclosed in Patent Document 2, for example.

JP 2006-039667 A JP 2002-501271 A

  In general, the resistive touch sensor can detect an operation using any input medium such as a stylus pen and a finger without selecting an operation medium. In terms of price, the resistive touch sensor is less expensive than the capacitive touch sensor. However, on the other hand, the resistive touch sensor cannot detect even if two different operations (so-called multi-touch) are performed, or it is difficult to detect unless a very special configuration is adopted. For this reason, it is difficult to detect an operation using two fingers, for example, separating the fingers in opposite directions or bringing them closer to each other.

  On the other hand, capacitive touch sensors have been developed that can handle multi-touch, making it possible to bring the operator's sense of operation closer to the output result after detection. . However, on the other hand, it is necessary for the operator to operate using a finger or a special pen having high conductivity. For this reason, for example, when an operator operates with gloves (insulating material), detection is likely to be difficult.

  Also, regarding the point of detecting the strength in the pressing direction, the resistance touch sensor cannot detect the strength in the pressing direction. In the capacitive touch sensor, the distance between the finger, which is one of the electrodes, and the electrode inside the sensor changes according to the strength of the pressure. Theoretically, the strength of the pressure is detected based on the change. Although possible, the change in capacitance based on the strength of the press is extremely weak, so that detection is difficult.

  An object of the present invention is to provide a touch sensor that can detect a plurality of operating points without selecting an input medium and can easily detect the strength in a pressing direction, and a touch pad including the touch sensor.

  In order to solve the above-described object, one embodiment of the present invention includes an insulating substrate and a sheet sensor disposed to face the substrate, and a plurality of electrodes are provided close to the surface facing the sheet sensor. A plurality of electrode groups are arranged, and the sheet sensor receives pressure from the side opposite to the substrate and comes into contact with one or more electrode groups so that the electrodes constituting the electrode groups can be electrically connected. It is the touch sensor which comprises.

  According to another aspect of the present invention, the electrode group on the substrate and the sheet sensor are prevented from contacting each other when at least one of the substrate and the sheet sensor is not pressed from the sheet sensor. It is a touch sensor provided with the insulation protrusion part which performs.

  Another aspect of the present invention is a touch sensor in which a surface or the entire surface of the sheet sensor facing the substrate is made of a resistive material that conducts between electrodes.

  Another embodiment of the present invention is a touch sensor having a configuration in which an electrode group is configured such that electrodes having a plurality of teeth are meshed so as not to contact each other.

  One embodiment of the present invention is an electronic device touchpad for operating an electronic device, which functions as a half mirror and can be operated on the surface from the front side, and is disposed on the back side of the operation plate, and an external light source A light guide plate capable of guiding light from the light guide and illuminating it toward the operation plate, and a touch sensor disposed on the back side of the light guide plate and capable of specifying the operation position by surface operation on the operation plate. The touch sensor includes an insulating substrate and a sheet sensor disposed to face the substrate, and the substrate includes an electrode configured by bringing a plurality of electrodes close to a surface facing the sheet sensor. An electronic device touch in which a plurality of groups are arranged, the sheet sensor receives pressure from the side opposite to the substrate, contacts one or more electrode groups, and allows conduction between the electrodes constituting the electrode groups It is a pad.

  According to another aspect of the present invention, the electrode group on the substrate and the sheet sensor are prevented from contacting each other when at least one of the substrate and the sheet sensor is not pressed from the sheet sensor. It is a touchpad for electronic devices provided with the insulation protrusion part to perform.

  Another embodiment of the present invention is a touch pad for an electronic device in which a surface or the entire surface of the sheet sensor facing the substrate is made of a resistive material that conducts between electrodes.

  Another embodiment of the present invention is a touch pad for an electronic device in which an uneven region that is easy to guide light in the direction of the operation plate is formed on a part of the light guide plate.

  Another embodiment of the present invention is a touch pad for an electronic device in which an uneven region is further formed on the surface of the light guide plate on the touch sensor side.

  According to the present invention, a touch sensor and an electronic device touch pad including the touch sensor can detect a plurality of operation points without selecting an input medium, and can easily detect the strength in the pressing direction.

FIG. 1 is a perspective view of a touch sensor according to an embodiment of the present invention. FIG. 2 is a perspective view showing a state in which the sheet sensor arranged opposite to the substrate is separated from the substrate constituting the touch sensor shown in FIG. 1 and the sheet sensor is turned upside down. FIG. 3 is an enlarged view showing an A portion of the sheet sensor shown in FIG. FIG. 4 is an enlarged view showing a B portion of the substrate shown in FIG. FIG. 5 is a cross-sectional view showing a partial cross section of the touch sensor shown in FIG. FIG. 6 is a view transparently showing the situation when pressing from above the sheet sensor shown in FIG. 1 toward the substrate. FIG. 7 is a diagram schematically illustrating a basic configuration of a control unit that detects a pressed position based on signals from each electrode group on the substrate illustrated in FIG. 2. FIG. 8 is a diagram for explaining another detection method different from the detection method of the pressed position described based on FIG. FIG. 9 is a diagram transparently showing the state of operation from above the sheet sensor that constitutes the touch sensor shown in FIG. FIG. 10 is a schematic diagram illustrating an electronic device touchpad according to an embodiment of the present invention and an electronic device that receives an operation from the touchpad and changes an image display. FIG. 11 is a perspective view of the touch pad shown in FIG. FIG. 12 is a plan view of the touch pad shown in FIG. 13 is an exploded perspective view of the touch pad shown in FIG. 14 is a cross-sectional view of the touch pad shown in FIG. 12 taken along line FF. 15 is a cross-sectional view showing a detailed configuration of the operation plate shown in FIG. FIG. 16 is a diagram transparently showing the state of operation from the operation plate constituting the touch pad shown in FIG.

  Next, an embodiment of a touch sensor according to the present invention and a touch pad for electronic equipment including the same will be described.

1. Touch Sensor FIG. 1 is a perspective view of a touch sensor according to an embodiment of the present invention. FIG. 2 is a perspective view showing a state in which the sheet sensor arranged opposite to the substrate is separated from the substrate constituting the touch sensor shown in FIG. FIG. 3 is an enlarged view showing an A portion of the sheet sensor shown in FIG. FIG. 4 is an enlarged view showing a B portion of the substrate shown in FIG.

  As shown in FIG. 1, a touch sensor 1 according to an embodiment of the present invention is a thin plate-like sensor having a rectangular plane, and a thin sheet-like sheet sensor 10 and an insulating property disposed so as to be opposed thereto. The substrate 20 is mainly configured.

  The sheet sensor 10 is made of a flexible material as a base material, preferably a thermoplastic elastomer or a thermosetting elastomer, more preferably silicone rubber. In addition, in the base material of the sheet sensor 10, a conductive material is dispersed in order to impart conductivity to the silicone rubber to obtain a desired resistance material. Examples of the conductive material include carbon black, metal, and the like, but carbon black that can easily manufacture particles with a small diameter (nano-level particles) and is easy to handle is more preferable. The mixing amount of the conductive material is preferably 5 to 50% by weight based on the total weight of the base material and the conductive material, from the viewpoint of enhancing the conductivity and maintaining the elasticity of the sheet sensor 10. 15 to 35% by weight is more preferable. The sheet sensor 10 preferably has an electric resistance in the range of 100 to 1700 ohms, more preferably 170 to 1000 ohms, as the contact resistance with the substrate 20 facing the sheet sensor 10. Note that the sheet sensor 10 is a base material composed of a plurality of layers, the layer facing the substrate 20 is formed of a resistive material imparted with conductivity, and a layer composed of an insulating material is pasted thereon. May be.

Further, the sheet sensor 10 includes a large number of insulating protrusions 11 dispersed on the surface facing the substrate 20. The protrusion 11 is preferably composed of a thermosetting resin, a thermoplastic resin, an ultraviolet curable resin, an electron beam curable resin, an elastomer, or the like excellent in insulating properties. For example, a polycarbonate (PC) resin, polyethylene terephthalate It is more preferably composed of (PET) resin and silicone rubber. The protruding portion 11 can be suitably formed by, for example, drying and curing an ink made of an insulating resin paint in a dot shape and then drying and curing. In addition, as long as the protrusion part 11 can ensure adhesiveness with the sheet | seat sensor 10, you may comprise from glass, ceramics etc. as materials other than the above, for example. When the protrusion 11 is not pressed from the sheet sensor 10, an electrode group 21 (described later) on the substrate 20 and the sheet sensor 10 come into contact with each other, and the electrodes 21 and 21 b constituting the electrode group 21 are electrically connected. It is a spacer for preventing the above. The protruding portion 11 has a substantially hemispherical shape with the protruding surface facing the substrate 20 side. In this embodiment, the protruding portion 11 is a thin hemisphere having a diameter of 0.1 mm and a height of 0.03 mm. However, the shape and size of the protruding portion 11 can be changed as appropriate, and may be connected in a route shape or a mesh shape without being dispersed. Note that the protruding portion 11 may be formed not on the sheet sensor 10 side but on the substrate 20 side.

  The substrate 20 is made of a material having higher rigidity than the sheet sensor 10 and is preferably a glass epoxy substrate in which a cloth knitted with glass fiber is impregnated with an epoxy resin. However, the substrate 20 may be a glass composite substrate, a ceramic substrate made of alumina or the like. The substrate 20 includes a large number of electrode groups 21 each having a plurality of electrodes arranged close to each other on the surface facing the sheet sensor 10. In this embodiment, as shown in FIG. 4, the electrode group 21 includes two substantially comb-shaped electrodes 21a and 21b having a plurality of teeth, and these electrodes 21a and 21b are meshed so as not to contact each other. It has a form. The electrodes 21a and 21b are thin films made of a material having excellent conductivity such as copper and silver, and can be suitably formed by means such as vapor deposition and printing. The electrode group 21 is positioned at the corners of the lattice on the substrate 20 so that the protrusions 11 formed on the sheet sensor 10 exist around the electrode group 21 when the sheet sensor 10 is disposed opposite to the substrate 20. Is formed. In this embodiment, the diameter of the virtual circumscribed circle of the electrode group 21 is about 3 mm, and the distance from the electrode group 21 adjacent in the vertical or horizontal direction is about 0.1 mm. It is not limited. In addition, the electrode group 21 does not necessarily have to be arranged at the corners of the lattice.

  FIG. 5 is a cross-sectional view showing a partial cross section of the touch sensor shown in FIG.

  When the sheet sensor 10 is pressed in the direction of the arrow from above, the surface of the sheet sensor 10 facing the substrate 20 comes into contact with the electrode group 21, and the electrode 21a and the electrode 21b constituting the electrode group 21 are brought into contact with each other. And are electrically connected. As a result, the pressed position can be specified.

  FIG. 6 is a view transparently showing the situation when pressing from above the sheet sensor shown in FIG. 1 toward the substrate.

  When the pressing area from the sheet sensor 10 is extremely large with respect to the area of the electrode group 21, the sheet sensor 10 can contact the plurality of electrode groups 21. The example shown in FIG. 6 is an example in which the sheet sensor 10 is in contact with the four electrode groups 21 in the contact regions 12, 13, 14, and 15, respectively. In this embodiment, an example in which the area of the contact area 12 is the largest of the four contact areas, and the area decreases in the order of the contact area 13, the contact area 14, and the contact area 15 will be described. The simplest position detection method is to determine that the electrode group 21 is pressed at the position of the contact area 12 having the largest area. When this detection method is employed, for example, when the sheet sensor 10 is pressed with a finger, even if there are a plurality of contact regions, the area of the electrode group 21 having the largest area and, as a result, the smallest detection voltage is obtained. The position is determined as the pressed position. Therefore, even if the sheet sensor 10 is in contact with the other electrode group 21, the position is ignored.

  FIG. 7 is a diagram schematically illustrating a basic configuration of a control unit that detects a pressed position based on signals from each electrode group on the substrate illustrated in FIG. 2.

  The control unit 30 shown in FIG. 7 includes a central processing unit (CPU) 31, a readable / writable memory (RAM) 32, and an analog / digital converter (A / D converter) 33. The control unit 30 may be provided either on the substrate 20 or other than the substrate 20. The CPU 31 has an electrical resistance value between the electrodes 21a and 21b that changes due to contact between the sheet sensor 10 and the electrode group 21, or a voltage value that changes according to the electrical resistance value (in this embodiment, representatively, “voltage value ”), The pressing position on the sheet sensor 10 is specified. More specifically, if the voltage value exceeds a predetermined threshold value, it is determined that the pressure has been applied, and if not, it is determined that the voltage value has not been pressed. As a result, not only one point but also multiple points can be detected. The RAM 32 is a storage unit that stores positional information (for example, XY coordinates) in association with a plurality of electrode groups 21 on the substrate 20. When the CPU 31 selects a specific electrode group 21 based on the voltage value, the CPU 31 can determine the coordinates of the electrode group 21 by referring to the information stored in the RAM 32. The A / D converter 33 is a part that converts an analog signal into a digital signal. The control unit 30 includes a circuit that connects the resistor R1 and the resistor R2 in series. The resistor R1 is a variable resistor 34, and actually corresponds to the electrode group 21. The resistor R2 is a resistor 35 having a fixed resistance value. Taking an electrode group 21 as an example, the voltage (VOut) between the electrodes 21a and 21b constituting the electrode group 21 is converted into a digital value by the A / D converter 33. The CPU 31 refers to the information in the RAM 32 and specifies the pressed position.

  FIG. 8 is a diagram for explaining another detection method different from the detection method of the pressed position described based on FIG.

In FIG. 8, the coordinates of (X1, Y1), (X2, Y1), (X1, Y2), (X2, Y2) correspond to the four electrode groups 21, and correspond to the coordinates (X1, Y2). The contact area 12 in contact with the sheet sensor 10 in the electrode group 21 that has the largest area corresponds to the contact area 13 and the coordinates (X1, Y1) in the electrode group 21 corresponding to the coordinates (X2, Y2). An example in which the area decreases in the order of the contact region 14 in the electrode group 21 and the contact region 15 in the coordinates (X2, Y1) will be described. The area of the contact region 12, the area of the contact region 13, the area of the contact region 14, and the area of the contact region 15 are S ₁₂ , S ₁₃ , S ₁₄ , and S _15, and S ₁₂ : S ₁₃ : S ₁₄ : S. ₁₅ = 0.5: 0.2: 0.16: 0.14. At this time, the coordinates (X, Y) of the pressing position determined by the CPU 31 are calculated by multiplying the four coordinates by the ratio of the respective contact areas and weighting the four coordinates. That is, X = X1 * 0.5 + X2 * 0.2 + X1 * 0.16 + X2 * 0.14, and Y = Y2 * 0.5 + Y2 * 0.2 + Y1 * 0.16 + Y1 * 0.14. As a result, when the sheet sensor 10 is pressed with a finger and there are a plurality of contact areas, it is possible to determine the coordinates close to the position where the contact area is large as the pressing position in consideration of the size of each contact area. it can. That is, unlike the case where the position having the largest contact area as described above is determined as the pressing position, analogly, coordinates other than the coordinates assigned to each electrode group 21 are determined as the pressing position. Is possible.

  FIG. 9 is a diagram transparently showing the state of operation from above the sheet sensor that constitutes the touch sensor shown in FIG.

  When two fingers are brought into contact with the sheet sensor 10 (contact areas C1 and C2) and the two fingers are moved closer to each other from the position, the contact points to the electrode group 21 move in a direction closer to each other. . As a result, the CPU 31 can detect the movement of the two fingers. Similarly, when two fingers are brought into contact with the sheet sensor 10 (contact areas D1 and D2) and the two fingers are moved away from the position, the contact points with the electrode group 21 move away from each other. Move to. As a result, the CPU 31 can detect the movement of the two fingers. When programming to change the image display method according to the movement of the coordinates of two points, for example, when two fingers are brought closer, the image is reduced, and when two fingers are moved away, the image is enlarged. It is also possible to do so. Since many electrode groups 21 are distributed on the substrate 20, even if there are two or more pressed portions from the sheet sensor 10, those pressed positions can be accurately detected.

2. Touchpad Next, an electronic device touchpad according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 10 is a schematic diagram illustrating an electronic device touchpad according to an embodiment of the present invention and an electronic device that receives an operation from the touchpad and changes an image display.

  An electronic device touchpad (hereinafter simply referred to as “touchpad”) 100 is an operation device capable of transmitting an operation signal to the electronic device 200 by wire or wirelessly, and is separate from the electronic device 200. It is configured. For example, when the operation surface of the touch pad 100 is operated diagonally right upward (direction indicated by E), the object 211 displayed on the display 210 of the electronic device 200 is in the state of the display 211a (displayed with a dotted line in FIG. 10). To the display 211b diagonally right upward (direction indicated by E). As described above, the image displayed on the electronic device 200 can be moved, rotated, enlarged / reduced, selected, and the like by receiving an operation from the touch pad 100.

  FIG. 11 is a perspective view of the touch pad shown in FIG. FIG. 12 is a plan view of the touch pad shown in FIG. 13 is an exploded perspective view of the touch pad shown in FIG.

  The touch pad 100 includes, in order from the upper housing 110 side, an operation plate 120, a light guide plate 130, a touch sensor 1 ′ (sheet sensor) in a space formed by aligning the upper housing 110 and the lower housing 160 with each other. 10 ′ and the substrate 20 ′) are stacked.

  The upper housing 110 is a thin and rectangular case preferably made of a hard resin such as polypropylene, and has a rectangular through-hole 111 at substantially the center in the surface thereof. Around the through hole 111, an inclined portion 112 is formed that gently inclines downward from the upper surface of the upper housing 110 toward the through hole 111. In addition, one side surface of the upper housing 110 has a small through hole 113 so that light can enter the inside through the through hole 113.

  The lower housing 160 has a substantially the same opening area as that of the upper housing 110, and is preferably a thin and rectangular case made of a hard resin such as polypropylene. Have The through hole 161 is a hole for electrically connecting the touch sensor 1 ′ to an external circuit board, a power source, or the like.

  The operation plate 120 functions as a half mirror and can be operated from the front side of the touch pad 100. As will be described later, the operation plate 120 is a multilayer plate in which a film is formed on a transparent plate made of resin or glass. The operation plate 120 is thinly formed to a level at which the operation can be transmitted to the inside when a touch operation is performed with a finger or the like from the front side. For example, a suitable thickness of the operation plate 120 is 80 to 150 μm.

  The light guide plate 130 is a member that is disposed on the back side of the operation plate 120 and that can guide light from an external light source and illuminate the operation plate 120. The light guide plate 130 is preferably made of a highly transparent resin such as an acrylic resin. However, the light guide plate 130 may be made of glass. The light guide plate 130 is thinly formed to a level at which an operation from the direction of the operation plate 120 can be transmitted to the back side. For example, a suitable thickness of the light guide plate 130 is 100 to 150 μm. The light guide plate 130 includes, in part, an uneven region 131 that is easily formed in the direction of the operation plate 120. In this embodiment, the uneven region 131 is formed on the back surface of the light guide plate 130 in the shape of the letter “P” in plan view. However, the uneven region 131 may be formed on the front surface or inside of the light guide plate 130. The roughness of the concavo-convex surface of the concavo-convex region 131 can be changed as appropriate depending on the amount of light from the light source, the transparency of the light guide plate 130, the distance from the operation plate 120, and the like. A range of about is preferred. The uneven area 131 can be suitably formed by mold transfer, laser etching, or the like. On the outer periphery of the front surface of the light guide plate 130, a protruding adhesive region 132 is formed. The adhesion region 132 can be suitably formed with, for example, a double-sided tape. By forming the adhesive region 132, an air layer can be formed between the operation plate 120 and the light guide plate 130. As a result, the light reflected by the uneven region 131 can be easily seen from the operation plate 120. it can.

  The sheet sensor 10 ′ constituting the touch sensor 1 ′ has substantially the same configuration as the sheet sensor 10 described above. Unlike the substrate 20 described above, the substrate 20 ′ constituting the touch sensor 1 ′ has a configuration in which a total of 49 electrode groups of 7 columns and 7 rows are concentrated in the central portion on the substrate 20 ′. . Other configurations of the substrate 20 ′ are the same as those of the substrate 20. The reason why the number of the electrode groups 21 is smaller than that of the electrode groups 21 on the substrate 20 and the electrodes 20 are gathered and arranged in the center of the substrate 20 ′ is that if the electrode groups exist in the region of the through hole 11 of the upper housing 110, This is because the useless electrode group does not need to be formed.

  14 is a cross-sectional view of the touch pad shown in FIG. 12 taken along line FF.

  As shown in FIG. 14, the through hole 113 formed in one side surface of the upper housing 110 is formed at the height of the side end surface of the light guide plate 130. An external light source (LED in this embodiment) 171 fixed on a circuit board 170 disposed outside is inserted into the through hole 113. As a result, the light from the LED 171 enters from the side end face of the light guide plate 130, is reflected by the uneven region 131, and can go to the operation plate 120 side. The through hole 113 may be formed on the lower housing 160 side.

  In FIG. 14, the protrusion formed on the surface facing the substrate 20 ′ of the sheet sensor 10 ′ is omitted for ease of viewing, but in a state where there is no pressure from above the sheet sensor 10 ′, The facing surface of the sheet sensor 10 ′ is held in a non-contact state with any electrode group 21 ′ using a number of protrusions as spacers.

  15 is a cross-sectional view showing a detailed configuration of the operation plate shown in FIG.

  The operation plate 120 is configured by laminating a hard coat layer 121, a transparent substrate 122, a reflective layer 123, and a concealing layer 124 in this order from the front side. The hard coat layer 121 is a layer formed to protect the transparent substrate 122 from scratches during operation. For example, UV curing acrylic resin, or thermosetting of melamine resin, epoxy resin, phenol resin, silicone resin or the like. It is preferably formed from a functional resin. A suitable thickness of the hard coat layer 121 is 1 to 20 μm.

  The transparent substrate 122 is preferably a PET resin, an acrylic resin, a polycarbonate resin, a polymer alloy composed of a polycarbonate resin and a polyester resin, an ABS resin, an AS resin, a polystyrene resin, a polyolefin resin, Alternatively, it is made of a vinyl chloride resin, and is particularly preferably constituted by a PET resin. A suitable thickness of the transparent substrate 122 is 80 to 100 μm.

  The reflective layer 123 has a function of reflecting light from the front side when the LED 171 is turned off and preventing the outline of the light-transmitting region from appearing thin. Further, the provision of the reflective layer 123 is more preferable because the surface to be used can be made smooth and glossy. For the reflective layer 123, a resin binder in which inorganic pigment particles or metal particles are dispersed can be used. As a material to be dispersed, for example, a pigment (pearl pigment) obtained by coating natural or synthetic mica with a metal oxide such as titanium oxide or iron oxide in addition to indium can be suitably used. A suitable thickness of the reflective layer 123 is 0.1 to 10 μm. The inorganic pigment particles or metal particles constituting the reflective layer 123 may exist in close contact or may be dispersed in an island shape.

  The concealing layer 124 is a layer for concealing the presence of the uneven region 131 from the operation surface side when the LED 171 is turned off. Since the concealing layer 124 can absorb a predetermined amount of light, it does not transmit light when the amount of light is small. On the other hand, when the amount of light is large, the concealing layer 124 transmits light that exceeds the amount of light that can be absorbed. That is, the concealing layer 124 is a layer having a light semi-transmissive function. The concealing layer 124 is preferably composed of, for example, black or a gray ink in which white is mixed with black, adjusted to have a total light transmittance of about 20%. It is desirable to adjust the total light transmittance by adjusting the black density in accordance with the light intensity of the internal light source. In addition, as the black pigment, for example, a particulate carbon material such as carbon black can be used, and the desired transmittance can be adjusted by controlling the content and dispersion state thereof. A suitable thickness of the masking layer 124 is 0.1 to 10 μm. Similar to the reflective layer 123, the concealing layer 124 may have its constituent particles in close contact or may be dispersed in an island shape.

  FIG. 16 is a diagram transparently showing the state of operation from the operation plate constituting the touch pad shown in FIG.

  The detection method of the pressed position by the touch sensor 1 ′ is common to that of the touch sensor 1 described above. For this reason, the touch pad 100 includes a control unit similar to the control unit 30 illustrated in FIG. When two fingers are brought into contact with the operation plate 120 of the touch pad 100 (contact areas G1, G2) and moved in the direction in which the two fingers are brought closer to each other, the contact points with the electrode group 21 ′ are mutually changed. Move in the direction of approach. As a result, the CPU 31 can detect the movement of the two fingers. Similarly, when two fingers are brought into contact with the operation plate 120 (contact areas H1 and H2), and the two fingers are moved away from the position, the contact points to the electrode group 21 ′ move away from each other. Move in the direction. As a result, the CPU 31 can detect the movement of the two fingers. When programming to change the image display method according to the movement of the coordinates of two points, for example, when two fingers are brought closer, the image is reduced, and when two fingers are moved away, the image is enlarged. It is also possible to do so. Since many electrode groups 21 ′ are distributed on the substrate 20 ′, even if there are two or more pressed locations from the operation plate 120, those pressed positions can be detected accurately.

3. Other Embodiments The touch sensor and the touch pad of the present invention are not limited to the above-described embodiments, and for example, the following modified implementation is possible.

  The sheet sensors 10 and 10 ′ constituting the touch sensors 1 and 1 ′ have a flat plate shape except for the protruding portion 11 in the above-described embodiment, but the substrates 20 and 20 are disposed on the surfaces facing the substrates 20 and 20 ′. A conductive protrusion that protrudes toward each electrode group 21, 21 ′ corresponding to the position of the “upper electrode group 21, 21 ′” may be provided. In that case, when the sheet sensor 10, 10 'is not pressed from above, the conductive protrusions are not in contact with the electrode groups 21, 21' so that the sheet sensor 10, 10 'is connected to the substrates 20, 20'. It is preferable to provide an insulating protrusion 11 on the opposite surface. In such a case, the protrusion 11 may be formed only around the surface of the sheet sensor 10, 10 'facing the substrate 20, 20'. In addition, an insulating region in which the electrodes 21a and 21b are not formed is formed in a substantially central portion of the electrode groups 21 and 21 ′, and the conductive protrusions are not pressed from above the sheet sensors 10 and 10 ′. Even if the tip contacts the substrates 20 and 20 ′, the electrodes 21a and 21b constituting the electrode groups 21 and 21 ′ may not be electrically connected.

  When the surface opposite to the surface facing the substrates 20 and 20 ′ in the sheet sensors 10 and 10 ′ is not black, the light from the LED 171 is transmitted between the light guide plate 130 and the sheet sensors 10 and 10 ′. It is preferable to dispose a concealing layer 124 that does not transmit light on the 10 ′ side. On the other hand, when the opposite surface of the sheet sensor 10 or 10 ′ is black, it is not always necessary to dispose the concealing layer 124. For example, in the case where the sheet sensors 10 and 10 ′ themselves are made of a resistive material in which carbon black is dispersed, the light from the LED 171 is transmitted to the sheet sensor 10 without separately providing the concealing layer 124. This is because it can be prevented from transmitting to the 10 ′ side. The hard coat layer 121 is not necessarily required when the transparent substrate 122 is made of glass.

  The present invention can be used as an operating device for operating an electronic device or a main part thereof.

1, 1 'touch sensor 10, 10' sheet sensor 11 protrusion 20, 20 'substrate 21a, 21b electrode 21, 21' electrode group 100 touch pad (touch pad for electronic equipment)
120 Operation plate 130 Light guide plate 131 Concavity and convexity region 171 LED (external light source)
200 Electronic equipment

Claims (9)

An insulating substrate;
A sheet sensor disposed opposite to the substrate,
The substrate has a plurality of electrode groups configured by bringing a plurality of electrodes in proximity to a surface facing the sheet sensor,
The sheet sensor is configured to receive pressure from the side opposite to the substrate and to contact one or two or more electrode groups, and to be able to conduct between the electrodes constituting the electrode groups. Touch sensor.   Insulation that prevents the electrode group on the substrate and the sheet sensor from coming into contact with each other when the electrode is not pressed from the sheet sensor to at least one of the substrate and the sheet sensor. The touch sensor according to claim 1, further comprising: a protruding portion.   3. The touch sensor according to claim 1, wherein the sheet sensor is configured by a resistive material that conducts between the electrodes, or the entire surface facing the substrate. 4.   The touch sensor according to any one of claims 1 to 3, wherein the electrode group has a form in which the electrodes having a plurality of teeth are meshed so as not to contact each other. An electronic device touchpad for operating an electronic device,
An operation plate that functions as a half mirror and can be operated from the front side.
A light guide plate that is disposed on the back side of the operation plate, guides light from an external light source, and illuminates the operation plate;
A touch sensor disposed on the back side of the light guide plate and capable of specifying an operation position by a surface operation on the operation plate;
With a stack,
The touch sensor includes an insulating substrate and a sheet sensor disposed to face the substrate.
The substrate has a plurality of electrode groups configured by bringing a plurality of electrodes in proximity to a surface facing the sheet sensor,
The sheet sensor is configured to receive pressure from the side opposite to the substrate and to contact one or two or more electrode groups, and to be able to conduct between the electrodes constituting the electrode groups. Touchpad for electronic equipment.   The electrode group on the substrate and the sheet sensor are prevented from contacting each other when the electrode sensor is not pressed from the sheet sensor to at least one of the substrate and the sheet sensor. The touch pad for electronic devices according to claim 5, further comprising an insulating protrusion.   The touch pad for an electronic device according to claim 5, wherein the sheet sensor is configured by a resistive material that conducts between the electrodes, or the entire surface facing the substrate.   The touch pad for electronic devices according to claim 5, wherein an uneven region that is easy to guide light in a direction of the operation plate is formed in a part of the light guide plate.   The touch pad for electronic devices according to claim 8, wherein the uneven area is formed on a surface of the light guide plate on the touch sensor side.

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