JP2014160316A - Capacitance input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitance input device capable of suppressing variations in sensitivity even if using a material with low conductivity as a material for a ground pattern.SOLUTION: A capacitance input device 1 includes: a substrate 10; an electrode pattern 2 laid on one surface of the substrate 10; and a ground pattern 3 laid on the other surface of the substrate 10. The ground pattern 3 has a first ground pattern 31 made of a first material 61, and a second ground pattern 32 made of a second material 62 with conductivity higher than that of the first material 61. The first ground pattern 31 is formed at least over an area 2B superimposed on the electrode pattern 2 in a plane view. The second ground pattern 32 is formed so as to surround the area 2B superimposed on the electrode pattern 2 in the plane view while contacting with the first ground pattern.

Description

  The present invention relates to a capacitance type input device, and more particularly to a capacitance type input device that detects an approach position of a finger or the like by a change in capacitance.

  The electrostatic capacitance type input device detects an electrostatic capacitance of a sensor unit and serves as an input device. The capacitance type input device includes, for example, a sensor unit in which a drive electrode and a detection electrode are formed on a substrate, a drive circuit that applies a drive signal to the drive electrode, and a detection circuit that processes a detection signal from the detection electrode. Including a circuit portion. Thereby, for example, the approach of a finger or the like can be detected by a change in capacitance between the drive electrode and the detection electrode. Further, if the drive electrode and the detection electrode are arranged at a plurality of positions, the approach position of a finger or the like can be detected.

  Capacitance type input devices are required to be resistant to noise generated from other electronic devices and static electricity caused by contact with charged fingers. In order to prevent noise and take measures against static electricity, a capacitance input device generally has a ground pattern in addition to the electrode pattern of the drive electrode and the detection electrode. Further, a ground pattern is provided on the lower side of the substrate on which the electrode pattern of the drive electrode and the detection electrode is formed (for example, the back surface side of the substrate) over a region overlapping the electrode pattern in plan view, thereby mixing in the detection signal. It is known that noise is reduced and the detection signal is stabilized.

  A flexible film base material can be used for the substrate of the capacitive input device. When the substrate is a film base, it is generally performed to provide a ground pattern by printing. By forming a ground pattern with a conductive material obtained by printing and heat-curing a conductive ink in which conductive powder (for example, metal powder) is mixed with a paste-like resin material, it is a relatively simple process. Can be manufactured.

  Patent Document 1 discloses an electrostatic capacitance type input device in which an electrode pattern is formed by printing, and a silver ink having a lower conductivity than that of a conductive ink (silver ink) for electrode pattern is printed on a ground pattern. ing.

  FIG. 8 is a plan view of the capacitive input device 100 disclosed in Patent Document 1. As shown in FIG. 9 is a partially enlarged longitudinal sectional view of a conventional capacitance type input device, and FIG. 9A is a partially enlarged longitudinal sectional view in which a part of the longitudinal sectional view cut along the line AA in FIG. 8 is enlarged. FIG. 9B is a partially enlarged longitudinal sectional view in which a part of the longitudinal sectional view cut along the line BB in FIG. 8 is enlarged. As shown in FIGS. 8 and 9, the front side 102 of the flexible film base 110 constitutes a sensor unit 120, and a plurality of Y are provided on the surface 110 a of the film base 110 directly or through an insulating layer. A drive electrode 111 and a plurality of detection electrodes 112 are formed. A sensor-side insulating layer 114 is provided on the surfaces of the Y drive electrode 111 and the detection electrode 112, and the X drive electrode 113 is formed on the sensor-side insulating layer 114.

  The back side 103 of the film base 110 constitutes a circuit portion, and a ground layer (shield layer) 117 made of a conductive material is formed on the back 110b of the film base 110. The ground layer 117 is formed so as to cover almost the entire operation surface from the back side. As shown in FIG. 9, the back surface of the ground layer 117 is covered with a circuit side insulating layer 118. A circuit wiring layer is formed on the back surface of the circuit side insulating layer 118.

JP 2012-190218 A

  However, since the ground pattern is necessary in a wide region having the same area or more as the electrode laying region, it is preferable to use a low-cost material instead of silver ink. On the other hand, since the low-cost material has low conductivity, the resistance value of the ground pattern using the material having low conductivity is increased. For this reason, when the resistance value of the ground pattern varies, there is a problem that the variation range of the resistance value is large and the detection sensitivity of the capacitance type input device varies. Therefore, a low-cost material with low conductivity could not be used.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object of the present invention is to provide a capacitive sensor that can suppress variations in sensitivity even when a material having a low conductivity is used as a material for a ground pattern.

  A capacitance-type input device according to the present invention comprises a substrate, an electrode pattern laid on one surface of the substrate, and a ground pattern laid on the other surface of the substrate. An apparatus, wherein the ground pattern includes a first ground pattern made of a first material and a second ground pattern made of a second material having a higher conductivity than the first material, and the first ground pattern Is formed over a region overlapping the electrode pattern in plan view, and the second ground pattern surrounds the region overlapping the electrode pattern in plan view in contact with the first ground pattern. It is formed.

  According to this configuration, the ground pattern laid on the other surface of the substrate is formed over a region where the first ground pattern overlaps the electrode pattern laid on one surface of the substrate in plan view, and the second ground The pattern is formed in a frame shape surrounding a region overlapping the electrode pattern in plan view. Since the second ground pattern is in contact with the first ground pattern, the resistance value of the ground pattern can be lowered by the second ground pattern. In this case, a material with low conductivity can be used as the first material. For this reason, even if a material with low electrical conductivity is used as the first material, the resistance value of the ground pattern can be lowered, so that variations in sensitivity can be suppressed. Furthermore, even if the second material having a high conductivity is expensive, the amount of the ground pattern used is small, so that the cost of the entire ground pattern can be reduced.

  In the capacitive input device according to the aspect of the invention, the other surface of the substrate may include an insulating layer stacked on at least a part of the first ground pattern, and the electrode laid on the other side of the insulating layer. A wiring pattern electrically connected to the pattern, wherein the wiring pattern is collectively formed by the second material for forming the second ground pattern.

  According to this configuration, the wiring pattern formed of the second material and the second ground pattern can be in the same process. In this way, the number of processes can be reduced compared to the case where the wiring pattern and the second ground pattern are formed separately.

  In the capacitance-type input device of the present invention, the first material is a conductive material containing carbon.

  According to this configuration, since the first material is a conductive material containing carbon, the cost is low. For this reason, even if the area of the first ground pattern is large, the cost of the ground pattern can be reduced.

  In the capacitance-type input device of the present invention, the second material is a conductive material containing silver.

  According to this configuration, since the second material is a conductive material containing silver, the conductivity is high. Thereby, even if the frame-shaped second ground pattern is formed thin, the resistance value of the ground pattern can be lowered.

  In the capacitance-type input device of the present invention, the first ground pattern is formed by printing.

  According to this configuration, since the first ground pattern made of the first material is formed by printing and curing the conductive ink material, it is less expensive than a method such as vapor deposition. In addition, it is easier to manufacture than methods such as vapor deposition.

  In the capacitance-type input device of the present invention, the second ground pattern is formed by printing.

  According to this configuration, since the second ground pattern made of the second material is formed by printing and curing the conductive ink material, a film forming method such as vapor deposition or a pattern forming method using photolithography Compared with, it is easy to manufacture. In addition, since the use efficiency of the material can be improved as compared with a method such as vapor deposition, the cost can be further reduced.

  According to the present invention, since the second ground pattern is formed in a frame shape surrounding the region overlapping the electrode pattern in plan view, even if the resistance value of the first ground pattern is high, the second ground pattern The resistance value can be lowered. In this case, a material with low conductivity can be used as the first material. For this reason, even if a material with low electrical conductivity is used as the first material, the resistance value of the ground pattern can be lowered, so that variations in sensitivity can be suppressed. Therefore, it is possible to provide a capacitance type input device that can suppress variations in sensitivity even when a material having low conductivity is used as the material of the ground pattern.

It is a schematic diagram which shows the electrostatic capacitance type input device of embodiment of this invention, (a) is a top view, (b) is a bottom view, (c) is a right view. It is the partial expanded sectional view which expanded a part of schematic sectional drawing cut | disconnected by the II-II line | wire of Fig.1 (a). It is the partial expanded sectional view which expanded a part of schematic sectional drawing cut | disconnected by the III-III line | wire of Fig.1 (a). It is a model bottom view explaining the board | substrate before forming a ground pattern. It is a model bottom view explaining a 1st ground pattern. It is a schematic diagram explaining a 2nd ground pattern and a wiring pattern. It is a schematic diagram explaining a 2nd ground pattern. It is a top view of the conventional electrostatic capacitance type input device. FIG. 9 is a partially enlarged longitudinal sectional view of a conventional capacitance type input device, and FIG. 9A is a partially enlarged longitudinal sectional view in which a part of the longitudinal sectional view taken along line AA in FIG. 8 is enlarged; ) Is a partially enlarged longitudinal sectional view in which a part of the longitudinal sectional view taken along line BB in FIG. 8 is enlarged.

[First Embodiment]
Hereinafter, a capacitive input device 1 according to an embodiment of the present invention will be described with reference to the accompanying drawings. Note that the dimensions of the drawings are changed as appropriate for easy understanding.

  FIG. 1 is a schematic diagram showing a capacitive input device 1 according to an embodiment of the present invention. FIG. 1 (a) is a plan view, FIG. 1 (b) is a bottom view, and FIG. ) Is a right side view. FIG. 2 is a schematic cross-sectional view taken along the line II-II in FIG. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG.

  As shown in FIGS. 1 to 3, the capacitive input device 1 according to the present embodiment includes a substrate 10, an electrode pattern 2 laid on one surface of the substrate 10 as an operation surface, and the other of the substrate 10. The ground pattern 3 laid on the surface and the circuit portion 7 are provided.

  The substrate 10 is a flexible film base having a thickness of about 0.2 mm, for example. The material of the substrate 10 is, for example, PET (polyethylene terephthalate). Note that through holes 15, 16, and 17 are formed in the substrate 10.

  As shown in FIG. 1A, the electrode pattern 2 laid on one surface of the substrate 10 includes a plurality of first electrodes 21 and a plurality of second electrodes 22. A range in which the electrode pattern 2 is disposed is defined as an electrode pattern region 2A.

  The plurality of first electrodes 21 are adjacent to each other with an interval in the X1-X2 direction, and each extend in the Y1-Y2 direction. The plurality of second electrodes 22 are adjacent to each other with an interval in the Y1-Y2 direction, and each extend in the X1-X2 direction. As shown in FIG. 2, the plurality of first electrodes 21 are disposed under the interlayer insulating layer 25 and the second electrode 22, and the second electrode 22 is in contact with the through-hole filler 66 at the position of the through-hole 16. . As shown in FIG. 3, the first electrode 21 is in contact with the through-hole filler 65 at the position of the through-hole 15. The first electrode 21 intersects under the interlayer insulating layer 25 and the second electrode 22 at the position of the intersection with the second electrode 22, and is not covered with the interlayer insulating layer 25 and the second electrode 22 in FIG. As shown in a), it is exposed in a substantially diamond shape. The second electrode 22 is formed to have a narrow width at the intersection with the first electrode 21, and is formed in a substantially rhombic shape that is wide in the Y1-Y2 direction at a position where the first electrode 21 is not exposed.

  As shown in FIG. 1B, the ground pattern 3 and the circuit portion 7 are formed on the other surface of the substrate 10. As shown in FIGS. 2 and 3, an insulating layer 4 and a protective layer 8 are also laminated on the other surface of the substrate 10, but in FIG. 1 (b), the ground pattern 3 is easy to understand. The insulating layer 4 and the protective layer 8 are omitted.

  The ground pattern 3 includes a first ground pattern 31 made of the first material 61 and a second ground pattern 32 made of the second material 62. Then, the first ground pattern 31 is formed over the entire other surface of the substrate 10, and the region 2 </ b> B that overlaps the electrode pattern 2 in plan view with the second ground pattern 32 in contact with the first ground pattern 31. It is formed in a frame shape surrounding. Note that openings are provided in the first ground pattern 31 and the insulating layer 4 at the positions of the through holes 15, 16, and 17. In FIG. 1B, the first ground pattern 31 and the second ground pattern 32 are hatched to show the ground pattern 3 in an easy-to-understand manner.

  The first material 61 is, for example, a conductive material containing carbon. The second material 62 is, for example, a conductive material containing silver.

  The circuit unit 7 includes a circuit board 71 on which an IC package 72 and a connector 73 are mounted. The circuit unit 7 electrically connects the plurality of first electrodes 21 and the plurality of second electrodes 22 via the wiring pattern 6 and through-hole fillers 65 and 66 formed in the through-holes 15 and 16 of the substrate 10. Connected. The IC package 72 is provided with a drive circuit and a detection circuit, and can process electrical signals using the plurality of first electrodes 21 and the plurality of second electrodes 22 as drive electrodes and detection electrodes. The connector 73 is a terminal for connecting an external wiring (not shown), supplying power to the drive circuit and the detection circuit, and outputting an output signal. In FIG. 1B, the wiring pattern 6 is also hatched for easy understanding.

  The capacitance type input device 1 is a device that detects the approach of a finger or the like based on changes in capacitance between the plurality of first electrodes 21 and the plurality of second electrodes 22. Since a plurality of first electrodes 21 provided in the X1-X2 direction and a plurality of second electrodes 22 provided in the Y1-Y2 direction of the electrode pattern region 2A that is the operation surface are arranged, for example, the following In this way, the planar position of a finger or the like on the operation surface can be detected.

  By a drive circuit provided in the IC package 72, a pulsed voltage is applied to the plurality of first electrodes 21 in order from the X1 side, for example, at regular time intervals.

If the first electrode 21 is X ₁ , X ₂ ,..., X _{m in} order from the X ₁ side, when a pulsed voltage is applied to X ₁ as a drive electrode, X ₂ is a detection electrode. It flows instantaneous current to X _2. This current depends on the magnitude of the capacitance formed between the X ₁ and X _2, when a finger or the like is approaching is formed between the X ₁ and X ₂ The amount of current changes because the size of the capacitance that changes. On the other hand, the next time, a pulse-like voltage as a drive electrode is applied to the X _2, as the detection electrode X _3, the amount of current is detected. In this way, until the order of the detection electrodes X _m, it is sequentially scanned in the X2 direction. In the amount of current using X ₁ , X ₂ ,..., X _m as detection electrodes, the amount of current of the detection electrode at the approach position of the finger or the like is different, so the X coordinate where the finger or the like is close can be estimated. In addition, when a pulsed voltage is applied to the drive electrode of the first electrodes 21, the other two first electrodes 21 at different positions are used as detection electrodes to simultaneously detect the respective current amounts. If so, the detection resolution for the X coordinate can be improved, and the X coordinate can be estimated more accurately.

Similarly, the same scanning can be sequentially performed on the second electrode 22 from the Y1 side. By a drive circuit provided in the IC package 72, a pulsed voltage is applied to the plurality of second electrodes 22 at regular time intervals, for example, in order from the Y1 side, and Y ₁ , Y ₂ ,. from the current amount of the respective detection electrodes Y _n, to estimate the Y-coordinate of a finger or the like approaches.

  By performing the scanning in the X direction and the scanning in the Y direction in order, the X coordinate and the Y coordinate that the finger or the like approaches are estimated. Such electrical scanning is completed in a short time and can be repeated, so that it is possible to estimate a moving operation when a finger or the like is tracing the operation surface.

  The capacitance detection method in the capacitance input device 1 is not limited to the above example. For example, the first electrode 21 is used as a drive electrode, and all the second electrodes 22 are used as detection electrodes. Other methods such as detecting each current amount in the direction may be used.

  As described above, the capacitance-type input device 1 uses the capacitance of the electrode pattern 2 (the plurality of first electrodes 21 and the plurality of second electrodes 22) laid on one surface of the substrate 10 as an operation surface. I try to detect it. At this time, the ground pattern 3 is laid around the electrode pattern 2 in order to suppress disturbance from other than the object such as a finger.

  In the present embodiment, the ground pattern 3 is laid on the other surface of the substrate 10 so that no disturbance is propagated from the opposite side of the operation surface to the electrode pattern 2. Further, the ground pattern 3 is grounded so that the detection of the capacitance is not unstable due to static electricity from a charged human body or the like. Therefore, the ground pattern 3 of the present embodiment is formed over the region 2B where the first ground pattern 31 made of the first material 61 overlaps the electrode pattern 2 in plan view, and disturbance from the opposite side of the operation surface does not propagate. To be done. Further, the second ground pattern 32 made of the second material 62 having higher conductivity than the first material 61 is formed in a frame shape surrounding the region 2B that overlaps the electrode pattern 2 in a plan view in contact with the first ground pattern 31. Thus, the ground resistance of the ground pattern 3 is reduced.

  As shown in FIGS. 1 to 3, a guard ring pattern 26 is formed on one surface of the substrate 10 as an operation surface in a region overlapping the second ground pattern 32 in plan view. The guard ring pattern 26 is grounded by being connected to the second ground pattern 32 through the through hole 17. The guard ring pattern 26 suppresses disturbance noise on the operation surface side and charging due to static electricity.

  In the capacitive input device 1 of the present embodiment, the first electrode 21, the second electrode 22, the first ground pattern 31, the second ground pattern 32, the wiring pattern 6, and the through-hole fillers 65 and 66 are respectively It is formed by printing. The first ground pattern 31 and the second ground pattern 32 in the print formation will be described with reference to FIGS.

  FIG. 4 is a schematic bottom view illustrating the substrate 10 before the ground pattern 3 is formed. FIG. 5 is a schematic bottom view illustrating the first ground pattern 31. FIG. 6 is a schematic diagram for explaining the second ground pattern 32 and the wiring pattern 6. FIG. 7 is a schematic diagram illustrating the second ground pattern 32.

  As shown in FIG. 4, through-holes 15, 16, and 17 are formed in the substrate 10 in advance. Then, through-hole fillers 65 and 66 are printed so as to fill the through-holes 15 and 16 (see FIGS. 2 and 3). Subsequently, the first electrode 21 is printed on one surface of the substrate 10 not shown in FIG. An interlayer insulating layer 25 is formed between the printing of the first electrode 21 and the printing of the second electrode 22, so that the intersection of the first electrode 21 and the second electrode 22 is not short-circuited as shown in FIG. Insulated. Subsequently, the second electrode 22 is printed. Note that the first electrode 21 may be configured in a two-layer structure with a wiring portion extending in the Y1-Y2 direction and a plurality of substantially rhombic electrode portions shown in FIG. For example, after forming a wiring portion with a narrow line width, it is possible to stack an approximately rhombus-shaped electrode layer shown in FIG. Further, this electrode layer may be formed when the second electrode 22 is printed. Also, the second electrode 22 may have a similar two-layer structure of a wiring portion and an electrode portion, and a substantially rhombic electrode layer may be laminated on each of the first electrode 21 and the second electrode 22. . FIG. 4 shows a region 2B that overlaps the electrode pattern 2 on which the first electrode 21 and the second electrode 22 shown in FIG.

  Next, the first ground pattern 31 is printed on the other surface of the substrate 10. By this printing, the first ground pattern 31 made of the first material 61 is formed as shown in FIG. At this time, openings 31 a are formed in the first ground pattern 31 in accordance with the positions of the through holes 15, 16, and 17 of the substrate 10.

  Subsequently, as shown in FIG. 6, an insulating layer 4 is formed in a region 2 </ b> B that overlaps the electrode pattern 2 in plan view in order to insulate the wiring pattern 6. An opening 4 a is also formed in the insulating layer 4 in accordance with the positions of the through holes 15 and 16 of the substrate 10. Subsequently, the second ground pattern 32 and the wiring pattern 6 are collectively formed by printing. By this printing, the second ground pattern 32 and the wiring pattern 6 made of the second material 62 are formed.

  At this time, the second ground pattern 32 is printed in a frame shape surrounding the insulating layer 4 as shown in FIG. As a result, the second ground pattern 32 comes into contact with the first ground pattern 31 shown in FIG. 5, and as shown in FIG. 7, it is formed in a frame shape surrounding the region 2B overlapping the electrode pattern 2 in plan view. The On the other hand, the wiring pattern 6 shown in FIG. 6 is not in contact with the first ground pattern 31 through the insulating layer 4. The wiring pattern 6 is laid on the other side of the insulating layer 4 and is electrically connected to the electrode pattern 2 in contact with the substrate 10 and the through-hole fillers 65 and 66 at the positions of the opening 4a and the opening 31a. The The second ground pattern 32 has a ground wiring 32 a connected to the circuit unit 7. Further, the second ground pattern 32 is formed with a pad portion 32b that can be connected to a ground terminal or the like of an electronic device on which the capacitive input device 1 is mounted (FIG. 7). The ground terminal of the electronic device and the ground pattern 3 are kept at the same potential (ground potential) via the pad portion 32b, and charging due to disturbance noise or static electricity can be more reliably suppressed. In the present embodiment, the second ground pattern 32 is formed in a continuous frame shape with no breaks, but there may be some breaks.

  Subsequently, a protective layer 8 covering the wiring pattern 6 is formed along the wiring pattern 6 except for a mounting land portion (not shown) that connects the circuit portion 7. A circuit board 71 on which the IC package 72 and the connector 73 are mounted is mounted on the mounting land part, and is connected to a connection part provided on the circuit board 71.

  For the interlayer insulating layer 25, the insulating layer 4, and the protective layer 8, it is preferable to use a resist material having excellent adhesion and insulating properties. For these, the same resist material may be used. Alternatively, a resist material having excellent adhesion and a resist material having excellent insulating properties may be stacked to have a structure of two or more layers. Each layer has a thickness of about several μm to several tens of μm. For example, as the interlayer insulating layer 25, three layers of resist materials can be laminated to a thickness of about 50 μm.

  The thicknesses of the first electrode 21, the second electrode 22, the first ground pattern 31, the second ground pattern 32, and the wiring pattern 6 are, for example, about several μm to several tens of μm. The line width of the wiring pattern 6 is, for example, about 0.1 mm.

  In the present embodiment, the first ground pattern 31 made of the first material 61 is formed by printing carbon paste as a conductive ink material. Carbon paste is a relatively inexpensive conductive material and is suitable for application over a large area. Moreover, there is little deterioration and it is excellent in long-term reliability. In the carbon paste, fine carbon fillers such as carbon black, carbon fibers, and carbon nanotubes are mixed in a molten binder resin. The carbon filler can be used alone or in combination of two or more as required, such as conductivity and printability, and those having different particle diameters can be used together. A carbon paste as a conductive ink material is screen-printed according to the shape of the electrode, dried and cured, or heat-cured.

  Since the first ground pattern 31 made of the first material 61 is formed by printing and curing a conductive ink material, it is less expensive than a method such as vapor deposition. In addition, it is easier to manufacture than methods such as vapor deposition. When the thickness of the first material 61 is about 10 μm, a resistance value of about 1 kΩ is obtained.

  In the present embodiment, the first electrode 21, the second electrode 22, the second ground pattern 32, and the wiring pattern 6 are formed of a second material 62 containing silver. The second material 62 uses a silver paste in which a powdery silver filler is contained in a molten binder resin as a conductive ink material, forms a pattern of an electrode layer by screen printing, and is cured by drying or heating. . Silver paste is a relatively expensive conductive material, but has high conductivity and excellent long-term reliability. When the thickness of the second material 62 is about 10 μm, a resistance value of about 0.1Ω is obtained. The same conductive material is also used for the through-hole fillers 65 and 66.

  Since the second ground pattern 32 made of the second material 62 is formed by printing and curing a conductive ink material, compared with a film formation method such as vapor deposition or a pattern formation method using photolithography, Easy to manufacture. In addition, since the use efficiency of the material can be improved as compared with a method such as vapor deposition, the cost can be further reduced.

  The first electrode 21 and the second electrode 22 may be formed by combining a wiring material having a thin line width but a low resistance and a laminated material formed in a predetermined area. For example, the same silver paste as the wiring pattern 6 can be used as the conductive ink material for the wiring material having a small line width but low resistance. The same carbon paste as the first ground pattern 31 can be used as the conductive ink material for the laminated material formed in a predetermined area.

  Hereinafter, the effect by having set it as this embodiment is demonstrated.

  In the capacitive input device 1 of this embodiment, the ground pattern 3 laid on the other surface of the substrate overlaps the electrode pattern 2 with the first ground pattern 31 laid on one surface of the substrate in plan view. The second ground pattern 32 is formed in a frame shape surrounding the region 2B that overlaps the electrode pattern 2 in plan view. Since the second ground pattern 32 is in contact with the first ground pattern 31, the resistance value of the ground pattern 3 can be lowered by the second ground pattern 32. In this way, a material with low conductivity can be used for the first material 61. For this reason, even if a material with low electrical conductivity is used for the first material 61, the resistance value of the ground pattern 3 can be lowered, so that variations in sensitivity can be suppressed. Furthermore, even if the second material 62 having a high conductivity is expensive, the amount of the ground pattern 3 as a whole can be reduced because the amount used to form the frame-shaped second ground pattern 32 is small.

  In the capacitive input device 1 of the present embodiment, the wiring pattern 6 formed of the second material 62 and the second ground pattern 32 can be made in the same process. In this way, the number of steps can be reduced compared to the case where the wiring pattern 6 and the second ground pattern 32 are formed separately.

  In the capacitance-type input device 1 according to the present embodiment, the first material 61 is a conductive material containing carbon, so that the cost is low. For this reason, even if the area of the first ground pattern 31 is large, the cost of the ground pattern 3 can be reduced.

  In the capacitance-type input device 1 of the present embodiment, the second material 62 is a conductive material containing silver, and therefore has high conductivity. Thereby, even if the frame-shaped second ground pattern 32 is formed thin, the resistance value of the ground pattern 3 can be lowered. For example, if the second ground pattern 32 is made of a material having the same conductivity as that of the wiring pattern 6, the line width of the second ground pattern 32 can be reduced, and the wiring pattern 6 and the second ground pattern 32 can be combined. Can be formed.

  In the capacitive input device 1 of the present embodiment, the first ground pattern 31 made of the first material 61 is formed by printing and curing a conductive ink material, so that it is compared with a method such as vapor deposition. And low cost. In addition, it is easier to manufacture than methods such as vapor deposition.

  In the capacitive input device 1 of the present embodiment, the second ground pattern 32 made of the second material 62 is formed by printing and curing a conductive ink material. Manufacture is easy compared with the pattern formation method using photolithography. In addition, since the use efficiency of the material can be improved as compared with a method such as vapor deposition, the cost can be further reduced.

  As described above, the capacitance-type input device 1 according to the embodiment of the present invention has been specifically described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. Can be implemented. For example, the present invention can be modified as follows, and these embodiments also belong to the technical scope of the present invention.

  (1) In the present embodiment, the first ground pattern 31 is formed on the entire other surface of the substrate 10. However, the first ground pattern 31 may not extend further from the position overlapping the second ground pattern 32. As long as the second ground pattern 32 is on the outer peripheral side of the region 2B that overlaps the electrode pattern 2 in plan view, the second ground pattern 32 may be located at a distance. In addition, in order to reduce the usage-amount of the 2nd material 62 as much as possible, it is preferable that it is a position near the area | region 2B which overlaps with the electrode pattern 2 by planar view.

  (2) In the present embodiment, the second material 62 forming the second ground pattern 32 has a higher conductivity than the first material 61 and a lower conductivity than the conductive material used for the wiring pattern 6. Also good. Although it cannot be formed together with the wiring pattern 6, the conductivity may be lower than that of the conductive material used for the wiring pattern 6 as long as it has a necessary conductivity as the ground pattern 3.

  (3) In the present embodiment, the operation surface is illustrated as a plane, but may be an operation surface having a curved surface.

DESCRIPTION OF SYMBOLS 1 Capacitance type input device 2 Electrode pattern 3 Ground pattern 4 Insulating layer 4a Opening part 6 Wiring pattern 7 Circuit part 8 Protective layer 10 Substrate 15, 16, 17 Through-hole 21 1st electrode 22 2nd electrode 25 Interlayer insulating layer 26 Guard ring pattern 31 First ground pattern 31a Opening 32 Second ground pattern 32a Ground wiring 32b Pad 61 First material 62 Second material 65, 66 Through-hole filler 71 Circuit board 72 IC package 73 Connector

Claims (6)

A substrate,
An electrode pattern laid on one side of the substrate;
A capacitance pattern input device comprising a ground pattern laid on the other surface of the substrate,
The ground pattern includes a first ground pattern made of a first material and a second ground pattern made of a second material having a higher conductivity than the first material,
The first ground pattern is formed over a region overlapping the electrode pattern in plan view,
The capacitance-type input device, wherein the second ground pattern is formed so as to surround a region overlapping the electrode pattern in a plan view in a state where the second ground pattern is in contact with the first ground pattern. On the other surface of the substrate, an insulating layer stacked on at least a part of the first ground pattern, a wiring pattern laid on the other side of the insulating layer and electrically connected to the electrode pattern, Have
The capacitance type input device according to claim 1, wherein the wiring pattern is collectively formed of the second material for forming the second ground pattern.   The capacitance-type input device according to claim 1, wherein the first material is a conductive material containing carbon.   4. The capacitive input device according to claim 1, wherein the second material is a conductive material containing silver. 5.   The capacitance type input device according to claim 1, wherein the first ground pattern is formed by printing. 6. The capacitive input device according to claim 1, wherein the second ground pattern is formed by printing.

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