JP4616324B2 - Touch sensor - Google Patents

Description

  The present invention relates to a capacitive touch sensor, and more particularly to a touch sensor incorporated as an input device in an electronic apparatus such as a lighting device or a display device.

  In recent years, electronic devices that can perform various input operations by combining a lighting device or a display medium with a touch sensor and detecting a position where a user touches with a finger or a pen have been used in various fields. Yes. In such an electronic device, a capacitive touch sensor is often used because it has few components and is advantageous for thinning.

Conventionally, regarding this type of touch sensor, a combination of two transparent substrates on which an ITO (indium tin oxide) film that becomes a conductive (electrode) pattern is formed is known (see Patent Documents 1 to 5). Moreover, what formed the ITO film | membrane on both surfaces of one film or plastics is known (refer patent document 6, 7).
JP 2003-271111 A JP 2003-173238 A JP 2003-114762 A Japanese Patent Laid-Open No. 10-214150 JP-A-9-120334 JP 2005-527048 A Special table 2003-511799 gazette

  By the way, a combination of two transparent substrates on which an ITO film is formed has a problem that the number of constituent members increases and it is difficult to reduce the weight and thickness. Further, in the case where an ITO film is formed on both surfaces of a single film, plastic, or film, there is a problem that it is technically difficult to form an ITO film on both surfaces of a film or plastic that is a base. In addition, since both surfaces of the substrate are wet-etched, the number of manufacturing steps is increased and the cost is increased. Furthermore, in wet etching, the ITO film formed on the surface is easily scratched, so that the yield may be reduced. In addition, ITO ink is known as a transparent conductive ink that can be printed. However, in order to obtain sufficient conductivity, it is necessary to bake at a high temperature, and it is technically difficult to apply to films and plastics. Yes.

  An object of the present invention is to provide a touch sensor that can be reduced in weight, thickness, and cost and can be easily manufactured.

  In order to achieve the above object, an invention according to claim 1 is a touch sensor in which a plurality of first and second electrode patterns are formed in a matrix with a transparent member interposed therebetween, wherein the first and first electrodes The two-electrode pattern is made of a transparent conductive material mainly composed of an organic conductive polymer. Each of the two-electrode patterns includes a region serving as a capacitance detection unit and a region serving as a non-capacitance detection unit. The gist is that they are configured so as not to overlap in a plane.

  In the invention according to claim 1, the regions that serve as the capacitance detection portions of the first and second electrode patterns do not overlap in a planar manner, but the regions that serve as the non-capacitance detection portions partially or entirely overlap. In addition, the non-capacitance detection unit means a region having a function of electrically connecting adjacent capacitance detection units, and even if the shape of the non-capacitance detection unit is not clear, a partial region of the capacitance detection unit is adjacent. When it is electrically connected to the capacitance detection unit, the partial region should be interpreted as corresponding to the non-capacitance detection unit.

  According to a second aspect of the present invention, in the first aspect, the plurality of first electrode patterns are on the first surface side of the transparent member, and the plurality of second electrode patterns are on the second surface side of the transparent member. And the transparent member includes a conductive portion that electrically conducts between the first surface and the second surface, and one electrode pattern of the first or second electrode pattern is the conductive portion. It is drawn out to the other electrode pattern side through the gist, and the gist is that the end portions of the first and second electrode patterns are electrically connected to the wiring pattern formed on the same surface.

  In the invention according to claim 2, it means that the first surface and the second surface of the transparent member are opposite to each other. That is, if the first surface is the surface of the transparent member, the second surface is the back surface of the transparent member, and if the first surface is the back surface of the transparent member, the second surface is the surface of the transparent member.

  In order to achieve the above object, the invention according to claim 3 is a touch sensor in which a plurality of first and second electrode patterns are formed in a matrix on one side of a transparent member. The second electrode pattern is made of a transparent conductive material having an organic conductive polymer as a main component, and a region serving as a capacitance detection unit and a region serving as a non-capacitance detection unit are formed. Each of the first and second electrode patterns at a portion where at least the non-capacitance detection portions of the first and second electrode patterns overlap in a plane. A transparent insulating film that electrically insulates between the non-capacitance detectors is formed.

  In the invention according to claim 1, since the first electrode pattern and the second electrode pattern are formed with one transparent member sandwiched therebetween, compared with a combination of two transparent substrates on which an ITO film is formed. Thus, the number of constituent members is reduced, and the weight, thickness, and cost can be reduced.

  In addition, the first electrode pattern and the second electrode pattern formed with a transparent member in between are transparent conductive materials mainly composed of organic conductive polymers, and therefore, on both surfaces of films and plastics compared to ITO films. It can be formed easily. In addition, since there is no need to wet-etch the electrode pattern, the number of manufacturing steps is not increased, and an increase in cost can be suppressed.

  Furthermore, since an electrode pattern formed of a transparent conductive material containing an organic conductive polymer as a main ingredient is not easily damaged like an ITO film, it is possible to suppress a decrease in yield. Moreover, since sufficient electroconductivity can be obtained without baking at a high temperature like ITO ink, it can be easily applied to films and plastics.

  In the invention according to claim 2, one electrode pattern is drawn out to the same surface side as the other electrode pattern by the conductive portion formed in the transparent member, and the end portions of the first electrode pattern and the second electrode pattern are respectively Since the structure is connected to the wiring pattern formed on the same surface, the wiring pattern can be formed by printing only on one side of the transparent member. According to this, since a manufacturing process can be simplified compared with manufacturing a wiring pattern in the front and back of a transparent member, cost reduction can be aimed at.

  Further, in the invention according to claim 3, in addition to the same effects as the invention according to claim 1, the electrode pattern is formed on one side of the transparent member. There is no need to reverse the transparent member as in the case of forming electrode patterns on the front and back surfaces, and the work can be simplified. In addition, the transparent member on which each electrode pattern is formed can be easily handled.

  Hereinafter, embodiments of a touch sensor according to the present invention will be described with reference to the drawings. Each figure schematically shows the structure of the touch sensor, and the ratio of each dimension is different from the actual one. Further, in order to facilitate understanding of the structure of the characteristic part of the invention, the shapes, lengths, thicknesses, etc., do not necessarily match each other in the drawings, and parts having different dimensional relationships and ratios are included. Specify clearly.

[Embodiment 1]
FIG. 1A is a plan view of the touch sensor according to the first embodiment, and FIG. 1B is a cross-sectional view taken along line AA in FIG. Note that FIG. 1B is schematically shown for easy understanding of the cross-sectional shape of the touch sensor, and some components such as a non-capacitance detection unit and a wiring pattern to be described later are omitted.

  The touch sensor 1 according to the present embodiment is based on a single transparent film 10 which is a transparent member, and a first electrode pattern 11 is formed on the front surface side, and a second electrode pattern 12 is formed on the back surface side. Among these, the first electrode pattern 11 on the front side has a plurality of rows arranged in the X direction in the drawing. The first electrode pattern 11 includes a capacitance detection unit 13a for detecting a capacitance change due to contact, and a non-capacitance detection unit 13b that electrically connects adjacent capacitance detection units 13a. Among these, the capacitance detection unit 13a is formed in a triangular shape, and the non-capacitance detection unit 13b is formed in a short strip shape. Similarly, the second electrode pattern 12 on the back side is arranged in a plurality of rows along the Y direction in the drawing. The second electrode pattern 12 includes a capacitance detection unit 14a for detecting a capacitance change due to contact, and a non-capacitance detection unit 14b that electrically connects adjacent capacitance detection units 14a. Among these, the capacitance detection unit 14a is formed in a triangular shape, and the non-capacitance detection unit 14b is formed in a short strip shape.

  And the 1st electrode pattern 11 and the 2nd electrode pattern 12 are arrange | positioned so that it may become a matrix (matrix) shape in planar view, as shown to Fig.1 (a). And the capacity | capacitance detection parts 13a and 14a in each electrode pattern are comprised so that it may not overlap planarly in the range shown by the capacity | capacitance detection area | region 100, and the non-capacitance detection parts 13b and 14b are comprised so that it may overlap.

  As the transparent film 10, for example, a film material made of a transparent synthetic resin such as PET (polyethylene terephthalate) can be used. As the 1st electrode pattern 11 and the 2nd electrode pattern 12, the transparent conductive material which has an organic conductive polymer as a main ingredient can be used. For example, a composition containing at least a polythiophene derivative polymer, a water-soluble organic compound, and dopand can be mentioned. By using a paste made of such an organic conductive polymer as a printing ink and patterning directly by, for example, screen printing, an electrode pattern having a predetermined shape can be formed on the surface of the transparent film 10. Alternatively, after the organic conductive polymer is coated on both surfaces of the transparent film 10, the electrode pattern can also be formed by partially degrading the organic conductive polymer layer with a transparent printing ink containing an acid or basic reagent. Can be formed. In addition, various methods such as gravure printing and inkjet printing can be used for patterning the electrode pattern. In addition, photolithography or the like that forms a predetermined pattern by exposing the surface of a substrate coated with a photosensitive substance in a pattern can also be used. That is, as long as a transparent conductive material mainly composed of an organic conductive polymer can be formed as the first electrode pattern 11 and the second electrode pattern 12, a method other than the above method can be used.

  Further, connection terminals 11a and 12a are formed at the end portions of the first electrode pattern 11 and the second electrode pattern 12, respectively. Among these, the connection terminal 11 a is electrically connected to the wiring pattern 16 formed on the surface side of the transparent film 10. On the other hand, a through hole 15 penetrating the front and back surfaces is formed in the transparent film 10 where the connection terminal 12a is formed. Then, the connection terminal 12a formed on the back surface side is drawn out to the surface side where the first electrode pattern 11 is formed through a conductive material (not shown) filled in the through hole 15, and formed on this surface side. It is electrically connected to the wiring pattern 17. In addition, although the terminal of each electrode pattern is not grounded and is in an electrically floating state, it may be in a grounded state. In the present embodiment, the through hole 15 and a conductive material (not shown) constitute a conductive portion that electrically connects the front and back surfaces.

  Each of the wiring patterns 16 and 17 described above is formed on the surface side of the transparent film 10, and each end is routed around one side of the transparent film 10. The connector 19 is electrically connected via the connecting member 18. The connector 19 is connected to a controller (not shown) that is an arithmetic device for position detection.

  The wiring patterns 16 and 17 can be formed by using silver paste and directly patterning, for example, by screen printing. In addition, as the connection member 18, for example, ACP (anisotropic conductive paste), ACF (anisotropic conductive film), or the like, a material that can be electrically conductively connected can be used.

  In the touch sensor 1 configured as described above, glass or a film (not shown) is further provided as a protective layer on the surface side of the transparent film 10.

  In the touch sensor 1 configured as described above, when a finger or a pen touches the range indicated by the capacitance detection region 100, the capacitance existing between the electrode pattern at the contact position and the contact object changes. Arise. That is, in the 1st electrode pattern 11 and the 2nd electrode pattern 12, the capacity | capacitance between the electrode pattern and the conductor which exists around each, and the capacity | capacitance between an electrode pattern and earth | ground exist, a finger | toe or a pen etc. When they come into contact with each other, the total capacitance including them increases, and decreases with distance. Such a change in capacitance is input from the connector 19 to a controller (not shown) through a wiring pattern connected to the corresponding electrode pattern. Changes in capacitance in the first electrode patterns 11 in a plurality of rows and the second electrode patterns 12 in a plurality of columns are sequentially read by a controller (not shown), and the electrode patterns in the X and Y directions in which the capacitance changes have occurred. By detecting this, the contact position of the finger or pen is specified. That is, the position of the intersection of the electrode patterns in the X and Y directions where the change in capacitance occurs is specified as the contact position of the finger or pen.

  Next, operations and effects of the touch sensor 1 configured as described above will be described. In the touch sensor 1 according to the present embodiment, the first electrode pattern 11 and the second electrode pattern 12 are formed with one transparent film 10 sandwiched therebetween, so two transparent substrates on which an ITO film is formed are combined. Compared to the conventional structure, the number of constituent members is reduced, and the weight, thickness, and cost can be reduced.

  Here, the difference between the structure of this embodiment and the structure of the conventional example will be described with reference to the drawings. FIG. 2 is a schematic cross-sectional view of a display device combined with a touch sensor, (a) is a schematic cross-sectional view of a display device combined with a touch sensor of the present embodiment, and (b) is a conventional structure (an ITO film is formed). It is a schematic sectional drawing of the display apparatus which combined the touch sensor of the structure which combined two films. Here, a display device having a structure in which a touch film is provided with a transparent film and a support will be described. The transparent film has a pattern or pattern drawn on the surface by printing. The support indicates a display medium itself such as glass, plastic, or a liquid crystal display device that constitutes a part of the display medium. In the following description, the electrode pattern formed on the film surface is not calculated as one layer.

  In the display device 20 combined with the touch sensor 1 of the present embodiment, as shown in FIG. 2A, a transparent film 22 is provided on the front side of the touch sensor 1 via optical glue 21, and the optical device is also provided on the back side. The support 23 is provided via the glue 21. On the other hand, in the display device 30 in which the touch sensor 31 having the conventional structure is combined, as shown in FIG. 2B, the touch sensor 31 includes two films 32 and 33 on which an ITO film is formed, and these two films. And a transparent adhesive layer (or dielectric layer) 34 sandwiched therebetween. Then, the transparent film 36 is provided on the front surface side of the touch sensor 31 via the optical glue 35, and the support 37 is provided on the rear surface side via the optical glue 35.

  As shown in FIG. 2A, in the display device 20 combined with the touch sensor 1 of the present embodiment, the transparent film 22 provided on the front surface side of the touch sensor 1 and the support body 23 provided on the back surface side are excluded. In contrast, the display device 30 combined with the touch sensor 31 having the conventional structure has a transparent film 36 provided on the front side of the touch sensor 31 and the three layers (touch sensor 1 layer + optical glue 2 layer). The portion excluding the support 37 provided on the back side is 5 layers (3 layers of touch sensor + 2 layers of optical paste).

  As described above, in the display device 20 combined with the touch sensor 1 of the present embodiment, the configuration of the touch sensor is one layer. Therefore, the number of constituent members is less than that of the display device 30 combined with the touch sensor 31 having the conventional structure. It is possible to reduce the weight, the thickness, and the cost.

  Moreover, in this embodiment, since the 1st electrode pattern 11 and the 2nd electrode pattern 12 are formed with the transparent electrically-conductive material which has organic electroconductive polymer as a main ingredient, compared with an ITO film | membrane, on both surfaces of a film or a plastic It can be formed easily. In addition, since there is no need to wet-etch the electrode pattern, the number of manufacturing steps is not increased, and an increase in cost can be suppressed. Furthermore, an electrode pattern formed of a transparent conductive material containing an organic conductive polymer as a main ingredient is unlikely to be scratched like an ITO film and can suppress a decrease in yield. Moreover, since sufficient electroconductivity can be obtained without baking at a high temperature like ITO ink, it can be easily applied to films and plastics.

  Further, in the present embodiment, the second electrode pattern 12 is drawn out to the same surface side as the first electrode pattern 11 by the through hole 15 formed in the transparent film 10 and the conductive portion made of a conductive material (not shown). Since the end portions of the first electrode pattern 11 and the second electrode pattern 12 are respectively connected to the wiring patterns 16 and 17 formed on the same surface, the wiring patterns 16 and 17 are formed by printing only on one side of the transparent film 10. can do. According to this, since the manufacturing process can be simplified as compared with manufacturing the wiring pattern on the front and back surfaces, the cost can be reduced.

  As described above, according to the touch sensor 1 according to the present embodiment, since the number of constituent members is reduced, the weight can be reduced, the thickness can be reduced, and the cost can be reduced, and the ITO film can be used as an electrode pattern. Therefore, manufacturing can be made easier.

[Embodiment 2]
Next, as Embodiment 2, a configuration in which the first and second electrode patterns are formed on one side of the transparent film will be described.

  3A and 3B are explanatory views showing the structure of the touch sensor according to the second embodiment. FIG. 3A is a plan view of the touch sensor, FIG. 3B is an enlarged view of a region where the non-capacitance detection units overlap, and FIG. It is BB sectional drawing of a). In addition, in each figure, the same code | symbol is attached | subjected to the part equivalent to Fig.1 (a).

  In the touch sensor 1A according to the present embodiment, the first electrode pattern 11 and the second electrode pattern 12 are formed in a matrix on one side of one transparent film 10 that is a transparent member. In each electrode pattern, the capacitance detection units 13 and 14 are configured not to overlap in a planar manner, and the non-capacitance detection units 13b and 14b are configured to overlap. In the present embodiment, as shown in FIG. 3B, an area where the non-capacitance detectors 13b, 14b overlap so that both detectors are not electrically connected in an area where the non-capacitance detectors 13b, 14b overlap. The transparent insulating film 2 is formed by a printing process, for example, between the printing processes of the non-capacitance detectors 13b and 14b. That is, as shown in FIG. 3C, the transparent insulating film 2 was formed on the surface layer of the second electrode pattern 12 formed on one side of the transparent film 10, and the first electrode pattern 11 was further formed thereon. It has a structure. However, the arrangement of the first electrode pattern 11 and the second electrode pattern 12 may be reversed. Further, in the configuration of the present embodiment, each electrode pattern exists on the same surface of the transparent film 10, so that no through hole is formed in the transparent film 10, and the connection terminals 11a and 12a of each electrode pattern are Each is connected to wiring patterns 16 and 17 formed on the same surface.

  Also in the configuration of the second embodiment described above, the same effects as those of the first embodiment can be obtained. In particular, in this embodiment, since the electrode pattern is formed on the same surface of the transparent film 10, there is no need to invert the transparent film 10 as in the case of forming the electrode pattern on the front and back surfaces of the transparent film 10, The work can be simplified. In addition, the transparent film 10 on which each electrode pattern is formed can be easily handled.

  Although the outline of the present invention has been described by the above embodiments, the description and drawings constituting a part of this disclosure do not limit the present invention. Various alternative embodiments are conceivable from this disclosure.

  For example, in the first and second embodiments, the example in which the shape of the capacitance detection units 13 and 14 is a triangle has been described. However, if the region serving as the capacitance detection unit can be configured so as not to overlap in a plane, a round shape, It may be a quadrilateral, hexagonal, or irregular shape.

  Moreover, in Embodiment 1 (FIG. 1), the 2nd electrode pattern 12 formed in the back surface side of the transparent film 10 formed the 1st electrode pattern 11 through the through hole 15 and the electroconductive material which is not shown in figure. Although an example of drawing to the front surface side has been described, the first electrode pattern 11 formed on the front surface side is drawn to the back surface side on which the second electrode pattern 12 is formed via the through hole 15 and a conductive material (not shown). You may comprise.

  In the second embodiment (FIG. 3), the transparent insulating film 2 is formed only in the region where the non-capacitance detectors 13b and 14b overlap, but the transparent insulating film 2 is formed over the entire surface layer of the second electrode pattern 12. However, the first electrode pattern 11 may be formed thereon. Similar effects can be obtained even with such a configuration.

  In the first and second embodiments, the transparent conductive material mainly composed of an organic conductive polymer is exemplified by a composition including at least a polythiophene derivative polymer, a water-soluble organic compound, and dopandoid. An electrode material not described here can be used as long as it is a substance that is mainly composed of a conductive polymer and is transparent and can be formed on a film or plastic as an electrode material.

  Further, the non-capacitance detection units 13b and 14b are regions having a function of electrically connecting adjacent capacitance detection units, and the shape thereof is not limited to the example of each embodiment. That is, even if the shape of the non-capacitance detectors 13b and 14b is not clear, when a partial region of the capacitance detectors 13a and 14a is electrically connected to an adjacent capacitance detector, this partial region is not It should be interpreted as corresponding to the capacity detectors 13b and 14b.

  Thus, it goes without saying that the present invention includes various embodiments and the like not described herein. Accordingly, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

FIG. 3 is an explanatory diagram illustrating a structure of a touch sensor according to the first embodiment. (A) is a top view of a touch sensor. (B) is the sectional view on the AA line of (a). The schematic sectional drawing of the display apparatus which combined the touch sensor. (A) is a schematic sectional drawing of the display apparatus which combined the touch sensor of embodiment. (B) is a schematic sectional drawing of the display apparatus which combined the touch sensor of the conventional structure. FIG. 6 is an explanatory diagram illustrating a structure of a touch sensor according to the second embodiment. (A) is a top view of a touch sensor. (B) is an enlarged view of a region where the electrode patterns of (a) overlap. (C) is the BB sectional drawing of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A ... Touch sensor 2 ... Transparent insulating film 10 ... Transparent film (transparent member)
DESCRIPTION OF SYMBOLS 11 ... 1st electrode pattern 11a, 12a ... Connection terminal 12 ... 2nd electrode pattern 13a, 14a ... Capacity | capacitance detection part 13b, 14b ... Non-capacitance detection part 15 ... Through-hole 16, 17 ... Wiring pattern 18 ... Connection member 19 ... Connector

Claims (2)

On a plane pattern with a transparent member in between ,
A plurality of first capacitance detection units, each of which is a right-angled isosceles triangle which is located on a straight line extending in the first direction and one of two sides having the same length, is a translational symmetry. A plurality of first electrode patterns each having a plurality of first non-capacitance detectors respectively connecting
A plurality of second capacitance detectors which are located on a straight line extending in a second direction perpendicular to the first direction and one of the two sides having the same length is a right-angled isosceles triangle which is translationally symmetric to each other; A plurality of second electrode patterns each having a plurality of second non-capacitance detectors respectively connecting a plurality of second capacitance detectors;
Is a touch sensor formed in a matrix,
It said first and second electrode patterns is made of a transparent conductive material to the base resin and the organic conductive polymer, region serving as each of the first and second capacitance detection portion is configured so as not to overlap in plan view The touch sensor characterized by being.   The plurality of first electrode patterns are formed on the first surface side of the transparent member, the plurality of second electrode patterns are formed on the second surface side of the transparent member, and the transparent member is formed on the first surface. A conductive portion that electrically conducts between the first surface and the second surface, wherein one electrode pattern of the first or second electrode pattern is drawn out to the other electrode pattern side through the conductive portion, The touch sensor according to claim 1, wherein end portions of the second electrode pattern are electrically connected to a wiring pattern formed on the same surface.

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