JP2007179561A - Input device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an input device whose thickness dimension can be made much thinner and whose costs can be reduced, and its manufacturing method. <P>SOLUTION: An X electrode layer 20X and a Y electrode layer 20Y are formed like a matrix through an insulating film 12 at one face side of a film substrate 10, and the end part of the X electrode layer 20X is guided to the end part of the film substrate 10. The Y electrode layer 20Y is guided through a through-hole formed in the insulating film 12 to the end part of the same face side of the X electrode layer 20X. The electrodes of the electrode layers 20X and 20Y guided to the end parts are connected to a conductive part 5 formed in a control circuit board 4. In this case, the electrodes and the conductive part 5 are heated and pressurized so as to be bonded to each other by insulating adhesive which does not include any conductive particle. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a capacitance type input device used as a pointing device of a personal computer, for example.

  FIG. 11 is a cross-sectional view schematically showing a conventional input device. The input device 100 is a pad type which is a kind of pointing device mounted on a notebook type personal computer.

  In the input device 100 shown in FIG. 11, an X electrode layer 103 composed of a plurality of X electrodes 102 is laminated on the upper surface of a synthetic resin film substrate 101 (detection substrate), and a plurality of Y electrodes are arranged on the lower surface of the film substrate 101. A Y electrode layer 105 composed of electrodes 104 is laminated, and the X electrode 102 and the Y electrode 104 are arranged in a matrix. The surfaces of the X electrode layer 103 and the Y electrode layer 105 are covered with insulating films 106 and 107, respectively. And the surface sheet 108 is provided in the X electrode layer 103 side used as the operation surface side. The electrode layers 103 and 105, the insulating films 106 and 107, and the surface sheet 108 have the same rectangular shape.

  In the input device 100, a control circuit board 110 is further provided in the lowermost layer opposite to the top sheet 108, and the control circuit board 110 is also formed with the same external dimensions as the film substrate 101. The control circuit board 110 is provided with a control circuit 111 on the surface opposite to the film board 101.

In the input device 100, through holes (not shown) are formed in the film substrate 101, the insulating film 107, and the control circuit substrate 110, respectively, and the X electrode layer 103 and the Y electrode layer 105 are electrically connected. A signal based on the capacitance detected by the X electrode layer 103 and the Y electrode layer 105 is sent to the control circuit 111.
Japanese Translation of National Publication No. 09-51086 Japanese Patent Laid-Open No. 11-135925 JP-A-10-242210 Japanese Patent Laid-Open No. 04-323714 JP 2000-151114 A

  However, since the conventional input device 100 has a configuration in which all of the electrode layers 103 and 105 including the film substrate 101 are provided on the control circuit substrate 110, the thickness of the entire input device is increased, and the notebook is increased. When mounted on a personal computer (PC), the thickness dimension of the PC cannot be further reduced. Further, since the control circuit board 110 has the same size (area) as the film board 101, the cost increases.

  The present invention solves the above-described conventional problems, and an object of the present invention is to provide an input device that can be further reduced in thickness and can reduce costs.

The present invention provides an input device in which an X electrode layer and a Y electrode layer for detecting capacitance are provided on a detection substrate.
The X electrode layer and the Y electrode layer are laminated on one surface of the detection substrate via an insulating film.

  In this case, a through hole is formed in the insulating film, and an end portion of one electrode layer is led to the same surface as an end portion of the other electrode layer through the through hole. The part and the conductive part of the control circuit board may be connected to face each other.

  In the present invention, since it is not necessary to provide a control circuit board directly under the detection board, the apparatus can be thinned and the control circuit board can be made small, so that the cost can be reduced.

  Further, it is preferable that the through hole is formed in a part of the X electrode layer or the Y electrode layer. Thereby, when one electrode layer is led to the same surface of the other electrode layer, the protruding shape of the detection substrate to the side can be kept small.

  In addition, a dummy electrode may be provided in parallel with the electrode layer between the adjacent X electrode layers and between the adjacent Y electrode layers.

  Further, if the detection substrate is a film substrate, the thickness dimension of the apparatus can be reduced.

  In addition, the detection substrate and the control circuit board are thermocompression bonded via a thermosetting adhesive in a state where the conductive portion of the control circuit board and the end portion of the electrode layer of the detection board are in contact with each other. Are preferably connected.

  In this case, the conductive portion of the control circuit board is formed with a through hole that penetrates and is electrically connected from one side of the control circuit board to the other side, and the adhesive is placed in the through hole portion. You may make it the structure which is located. By adopting such a configuration of bonding, the bonding strength can be improved.

  In the present invention, since the thickness dimension of the apparatus can be made thinner than before, it can be made thinner when mounted on a notebook computer. In addition, the control circuit board can be formed smaller than the conventional control circuit board, and it is not necessary to use a multi-layer board such as four layers, so that the cost can be reduced.

  1 is an exploded perspective view showing an input device according to the present invention, FIG. 2 is a circuit wiring diagram showing electrodes of an X electrode layer, FIG. 3 is a plan view showing through holes formed in an insulating film, and FIG. 4 is a Y electrode layer. 5 is a cross-sectional view showing a part when cut in the X direction, FIG. 6 is a cross-sectional view showing a part when cut in the Y direction, and FIG. 7 is a cross-sectional view of the X electrode layer and the Y electrode layer. It is sectional drawing which shows a part when cut | disconnecting in a connection part.

  The input device 1 shown in FIG. 1 is provided with a film substrate 10 as a detection substrate of the present invention. The film substrate 10 is formed of an insulating synthetic resin sheet such as PET (polyethylene terephthalate). As shown in FIG. 1, the film substrate 10 is formed with an extension 11 in which one side in the longitudinal direction protrudes laterally.

  An X electrode layer 20 </ b> X is provided on the lower surface of the film substrate 10. In the X electrode layer 20X, as shown in FIG. 2, a plurality of (16) X electrodes x1, x2,..., X15, x16 are formed in parallel to each other at a predetermined interval in the X direction. A drive electrode 20Xd is formed. One end of each of these X electrodes x1, x2,..., X15, x16 extends to the extension portion 11.

  In the X electrode layer 20X formed on the film substrate 10, dummy electrodes xd (15 in total) are alternately formed between the X electrodes x1, x2,..., X15, x16. By providing the dummy electrode xd, it is possible to disperse the influence when water droplets adhere to the surface of the input device 1, for example.

  In addition, a ground electrode 21 is formed on the film substrate 10 on the same surface as the X-direction drive electrode 20Xd, extending to the extension 11 along the peripheral edge of the film substrate 10. In the space formed between the X-direction drive electrode 20Xd and the ground electrode 21 of the film substrate 10, X switching electrodes 22, 23, 24 composed of a plurality of electrodes are formed. These X direction drive electrode 20Xd, ground electrode 21, and X switching electrodes 22, 23, 24 are all formed by screen printing using silver paste or silver paste.

  An insulating film 12 formed by applying or printing an insulating resin (resist) is provided on the surface of each electrode 20X, 21, 22, 23, 24. This resist can be selected from, for example, polyamide, epoxy resin, polyurethane and polyester. At this time, a plurality of through holes h1, h2,..., H12, k2, k4,..., K10, m2, m4,. Yes. These through holes are formed at positions that coincide with one end of the X switching electrodes 22, 23, 24. In addition, the electrode shown in FIG. 2 in which the through hole corresponding to FIG. 3 is not formed is an inspection electrode.

  As shown in FIG. 4, a Y electrode layer 20 </ b> Y is provided on the surface (lower surface) of the insulating film 12. In the Y electrode layer 20Y, a Y direction drive electrode 20Yd composed of a plurality (12) of Y electrodes y1, y2,..., Y11, y12 is formed in a direction orthogonal to the X direction drive electrode 20Xd. Further, one end of the electrodes y1, y3, y5, y7, y9, y11 of the Y electrodes y1, y2,..., Y11, y12 has predetermined through holes shown in FIG. It extends to the position of.

  On the surface (lower surface) of the insulating film 12, a detection electrode S is provided in the same layer as the Y-direction drive electrode 20Yd. The detection electrode S is composed of comb-like electrodes sa and sb, and the electrodes ys of the comb-like electrodes sa and sb are alternately formed with the Y electrodes y1, y2,. Further, in the comb-shaped electrodes sa and sb, the tips of the comb teeth are formed in opposite directions, and the comb-shaped electrodes sa and sb are combined into one electrode at the center in the Y direction. It extends to the position of a predetermined through hole shown in FIG.

  In FIG. 3, the X electrode layer 20 </ b> X is indicated by a thick white line, and in FIG. 4, the Y electrode layer 20 </ b> Y is indicated by a thin solid line, but both electrodes are formed by electrodes having substantially the same width.

  As shown in FIG. 1, an insulating film 13 made of an insulating resin similar to the insulating film 12 is formed on the entire surface including the Y-direction drive electrode 20Yd by printing. On the upper surface of the film substrate 10, a surface sheet 14 is fixed with an adhesive or the like, which is a portion that a finger or pen touches when operated by an operator.

  Thus, when the X electrode layer 20X and the Y electrode layer 20Y are formed on one surface of the film substrate 10, it is necessary to guide each electrode of the Y electrode layer 20Y to the surface on which the X electrode layer 20X is formed. Therefore, the electrode forming means in this embodiment will be described below with reference to FIGS.

  In the Y electrode layer 20Y, one end of each of the Y electrodes y1, y3, y5, y7, y9, y11 is formed to extend, and the end of each electrode extends to the contacts b1, b3, b5, b7, b9, b11. Yes. The Y electrodes y1, y3, y5, y7, y9, y11 are connected to the contacts a1, a3 of the X switching electrode 24 through through holes h1, h3, h5, h7, h9, h11 formed in the insulating film 12, respectively. , A5, a7, a9, a11.

  The end portions b2, b4, b6, b8, b10, b12 of the Y electrodes y2, y4, y6, y8, y10, y12 are through holes h2, h4, h6, h8, h10 formed in the insulating film 12. , H12 are connected to contacts a2, a4, a6, a8, a10, a12 at the ends of the X switching electrodes 22, 23, respectively. Here, only the contact a <b> 12 is formed so as to extend to the end of the extension portion 11 as it is. Further, contacts c2, c4, c6, c8, c10 formed on the opposite side of the contacts a2, a4, a6, a8, a10 of the X switching electrodes 22, 23 are through holes k2, formed in the insulating film 12. It is connected to the contacts d2, d4, d6, d8, d10 of the Y switching electrode 26 through k4, k6, k8, k10. The contacts e2, e4, e6, e8, e10 formed at the end opposite to the contacts d2, d4, d6, d8, d10 are through holes m2, m4, m6, m8, m10 of the insulating film 12. Are connected to contacts f2, f4, f6, f8, f10 formed on the X switching electrode 24. In this way, the Y electrodes y2, y4, y6, y8, y10, y12 are guided from the Y electrode layer 20Y to the same surface as the X electrode layer 20X.

  Further, a contact s1 formed extending from the detection electrode S formed on the Y electrode layer 20Y is connected to a contact s3 of the X switching electrode 24 through a through hole s2 of the insulating film 12.

  By forming the circuit as described above, all the electrodes of the X electrode layer 20 </ b> X and the Y electrode layer 20 </ b> Y can be collected at the end portion Ds of the extension portion 11 of the film substrate 10.

  As shown in FIG. 5, in the input device 1, the film substrate 10 is overlapped with the surface sheet 14 slightly protruding from both left and right sides in the X direction, and further, as shown in FIG. 6, the longitudinal direction of the surface sheet 14. Are overlapped so that one edge of the film coincides with the edge of the film substrate 10. Therefore, when the input device 1 is viewed from the upper side of the top sheet 14, the film substrate 10 is overlapped with the left and right sides of the top sheet 14 protruding in the extension portion 11.

  In the portion where the X electrode layer 20X and the Y electrode layer 20Y are connected via a through hole, as shown in FIG. 7, when the Y electrodes y2, y4,. The formed through holes h2, h4,... Are filled with silver or a silver-based paste to form an electrical connection state with the contacts a2, a4,. On the other hand, the Y electrodes y1, y3,... Are connected to the X switching electrode 24 on the X electrode layer 20X side through a through hole at another position through the surface of the insulating film 12.

  As described above, the circuit pattern of the Y electrodes y1, y2,..., Y11, y12 is divided into the upper surface and the lower surface of the insulating film 12, whereby the pitch between the electrodes can be narrowed. Therefore, even if the electrode on the upper surface side and the electrode on the lower surface side of the insulating film 12 are overlapped with each other, they do not conduct each other. As a result, the external dimensions of the input device 1 can be reduced.

  As shown in FIG. 2, in the input device 1 according to the present embodiment, all the electrodes of the X electrode layer 20X and the ends Ds of all the electrodes of the Y electrode layer 20Y Guided to the end. In addition, since the protrusion dimension (L2) which overlaps with the extension part 11 of the insulating films 12 and 13 is formed shorter than the protrusion dimension (L1 + L2) of the extension part 11 on the surface (lower surface) side of the film substrate 10, When the insulating films 12 and 13 are laminated on the film substrate 10, the end Ds of the electrode layer formed on the surface of the film substrate 10 is exposed on the surface (see FIG. 1).

  The end portions Ds of the X electrode layer 20X and the Y electrode layer 20Y are connected to the conductive portion 5 formed on the control circuit board 4. The control circuit board 4 is formed with an outer dimension that is sufficiently smaller than the film board 10. A portion of the dimension L exposed at this time is a region connected to the conductive portion 5.

  The control circuit board 4 is formed of a board 4a made of paper phenol, paper epoxy, glass epoxy, or the like, and a conductive part 5 connected to the end Ds of the electrode layer is formed on one side of the board 4a. . The conductive portion 5 has a plurality of lands 5a formed at predetermined intervals in the X direction. The conductive portion 5 can be formed of a copper foil or a metal surface such as copper plated with gold or carbon, but it is preferable to use a gold plated one in consideration of resistance and bonding strength.

  Each land 5a of the control circuit board 4 is divided into land portions 5a1 and 5a2 by a gap 5b with a minute interval. Also, land portions 7a1 and 7a2 having the same pattern as the conductive portion 5 are formed on the back surface side of the control circuit board 4 (see FIG. 10). The land portions 5a1 and 5a2 are formed with through holes 6a and 6b penetrating the land portions 7a1 and 7a2, and the through holes 6a and 6b are covered with a conductive material of the same material as the copper foil or the like. Thus, the land portions 5a1 and 5a2 and the land portions 7a1 and 7a2 are electrically connected. The land portion 7a1 is formed by extending a circuit pattern around the control circuit board 4, and is connected to the control circuit 8 mounted on the board 4a. The land portions 5a2 and 7a2 are inspection circuits.

  As shown in FIG. 8, in the input device 1 according to the present embodiment, each gap formed in the conductive portion 5 when the end portions Ds of the electrode layers 20X and 20Y and the control circuit board 4 are connected. A thermosetting adhesive 30 (shaded portion in FIG. 8) is applied to 5b in a single character form. The adhesive 30 is fluid having insulating properties that do not contain conductive particles. For example, an epoxy resin can be used.

  After the adhesive 30 is applied to the region including the gap 5b in a single character, the end portion Ds is positioned with respect to the conductive portion 5 and bonded by heating and pressing. FIG. 9 shows a state after joining, and FIG. 10 shows a cross-sectional view taken along line 10-10 in FIG. By heating and pressing the adhesive 30, the adhesive 30 passes through the gap 5 c from the gap 5 b through the gap 5 c between the land portions 5 a 1 and 5 a 1 and the gap 5 d between the land portions 5 a 2 and 5 a 2. Spreads to. As the adhesive 30 flows in this manner, the film substrate 10 and the control circuit substrate 4 are bonded to each other at the upper and lower sides where the gaps 5c and 5d are formed. Further, by applying pressure, the adhesive 30 can be removed from the joint surface T between each electrode of the end portion Ds and each of the land portions 5a1 and 5a2 of the conductive portion 5, so that the end portion Ds and the conductive portion 5 are electrically connected. Can be joined.

  Further, the adhesive 30 applied to the surfaces of the land portions 5a1 and 5a2 is transferred from the surfaces of the land portions 5a1 and 5a2 into the through holes 6a and 6b and escapes, so that the adhesive 30 enters the through holes 6a and 6b. By curing in a state where the control circuit board 4 is positioned, the bonding strength between the control circuit board 4 and the end Ds can be improved. Further, by providing a dummy conductive part in the vicinity of the conductive part 5 of the control circuit board 4 and providing a dummy electrode at a position overlapping the dummy conductive part of the film substrate 10, the bonding strength can be further improved.

  In the input device 1 of the present embodiment, detection is performed by the X-direction drive electrode 20Xd, the Y-direction drive electrode 20Yd, and the detection electrode S.

  That is, a finger or the like is applied to the top sheet 14 with an electric field having a predetermined potential between all the X direction drive electrodes 20Xd (X electrodes x1... X16) and the Y direction drive electrodes 20Yd (Y electrodes y1... Y12). When the conductor is touched, the capacitance between the X-direction drive electrode 20Xd and the Y-direction drive electrode 20Yd changes at the touched position.

  When obtaining the X coordinate data, two X direction drive electrodes 20Xd are selected as one bundle, and a detection output corresponding to a change in capacitance between the X direction drive electrode 20Xd and the detection electrode S is obtained. Further, when obtaining the Y coordinate data, two Y direction drive electrodes 20Yd are selected as one bundle, and a detection output corresponding to a change in electrostatic capacitance between the Y direction drive electrode 20Yd and the detection electrode So is obtained. Then, detection outputs from all electrodes of the X direction detection electrode 20Xd and detection outputs from all electrodes of the Y direction detection electrode 20Yd are alternately performed in a time division manner.

  The detection output obtained in this way is amplified by an amplifier, converted to a digital signal by an A / D converter, and subjected to a predetermined calculation by a control unit and sent to the PC main unit. Control based on the calculation result is performed.

An exploded perspective view showing the input device of the present invention, Circuit wiring diagram showing the X electrode layer, A plan view showing a through hole formed in the insulating film, Circuit wiring diagram showing the Y electrode layer, Sectional drawing which shows a part when cut | disconnecting by a X direction, Sectional drawing which shows a part when cut | disconnecting in a Y direction, Partial cross-sectional view when cut at the connection portion of the X electrode layer and the Y electrode layer, A plan view showing a conductive portion of the control circuit board, The top view which shows the state with which the control circuit board and the electrode layer were joined, FIG. 10 is a cross-sectional view taken along line 10-10 in FIG. Sectional drawing which shows the simplified state of the conventional input device,

Explanation of symbols

Ds End of electrode layer S Detection electrode sa, sb Comb electrode x1 ... x16 X electrode y1 ... y12 Y electrode 1 Input device 4 Control circuit board 5 Conductive part 5a Land 5a1, 5a2, 7a1, 7a2 Land part 5b Gap 5c, 5d Clearance 6a, 6b Through hole 8 Control circuit 10 Film substrate (detection substrate)
11 Extension parts 12, 13 Insulating film 14 Top sheet 20X X electrode layer 20Y Y electrode layer 20Xd X direction drive electrode 20Yd Y direction drive electrode 21 Ground electrodes 22, 23, 24 X switching electrode 26 Y switching electrode 30 Thermosetting adhesion Agent

Claims (7)

In an input device in which an X electrode layer and a Y electrode layer for detecting capacitance are provided on a detection substrate,
The input device, wherein the X electrode layer and the Y electrode layer are laminated on one surface of the detection substrate via an insulating film.   Through holes are formed in the insulating film, and the end portions of one electrode layer are led to the same surface as the end portions of the other electrode layer through the through holes, the end portions of the two electrode layers, The input device according to claim 1, wherein the conductive portion of the control circuit board is connected to face to face.   The input device according to claim 2, wherein the through hole is formed in a part of the X electrode layer or the Y electrode layer.   The input device according to claim 1, wherein dummy electrodes are provided in parallel with the electrode layers between the adjacent X electrode layers and between the adjacent Y electrode layers.   The input device according to claim 1, wherein the detection substrate is a film substrate.   With the conductive portion of the control circuit board and the end of the electrode layer of the detection board in contact, the detection board and the control circuit board are connected by thermocompression bonding via a thermosetting adhesive. The input device according to claim 2 or 3.   The conductive portion of the control circuit board is formed with a through hole that penetrates and is electrically connected from one side of the control circuit board to the other side, and the adhesive is located in the through hole portion. The input device according to claim 6.

Images