JP4435622B2 - Capacitance type detection device - Google Patents

Description

  The present invention relates to a capacitance-type detection device used for a touch panel or a glide point, and more particularly to a capacitance-type detection device that is less susceptible to influences from outside the sensing region and increases detection accuracy.

As a prior art related to a capacitance type detection apparatus, for example, there is a pad type pointing device as shown in Patent Document 1 below.

  In Patent Document 1, an X electrode layer 20X comprising a plurality of X electrodes x1, x2,..., X15, x16 extending in the X direction and arranged at predetermined intervals in the Y direction is provided on the lower surface of the film substrate 10, An insulating film 12 is formed on the surface (lower surface) of the X electrode layer 20X, and a plurality of Y electrodes y1, extending in the Y direction on the surface (lower surface) of the insulating film 12 and arranged at predetermined intervals in the X direction. A Y electrode layer 20Y made of y2,..., y15, y16 is formed. In other words, the X electrode layer 20X and the Y electrode layer 20Y are provided on the lower surface of the film substrate 10 so as to face each other in a matrix form orthogonal to each other with the insulating film 12 interposed therebetween.

The Y electrodes y 1, y 2,..., Y 15, y 16 and the X electrodes x 1, x 2,. Finally, they are collected at the end portion Ds of the extension portion 11 of the film substrate 10 and connected to the conductive portion 5 of the control substrate circuit 4 therefrom.
JP 2003-99185 A

  The capacitance type detection device is configured such that when a detected object such as a finger is brought close to the X electrode layer and the Y electrode layer, the detected object and each X electrode, and the detected object and each By detecting a change in capacitance formed between the Y electrode and the Y electrode, the position of the detected object in the X and Y directions is detected.

  Therefore, in order to increase the detection accuracy in the X and Y directions, when the detected object approaches the electrodes other than the X and Y electrodes, no capacitance is formed between the electrodes and the detected object. Or, even if the capacitance is formed, it is necessary that the amount of change is small.

  However, in the above-described conventional electrostatic capacitance type detection device, the drawer is extended from the ends of the Y electrodes y1, y2,..., Y15, y16 and the X electrodes x1, x2,. Since the wire is arranged adjacent to the Y electrode or the X electrode, a capacitance is easily formed between the lead wire and the detection object, and the amount of change cannot be reduced. Therefore, there is a problem that it is difficult to increase the accuracy of detecting the position of the detection target in the X and Y directions.

  The present invention is for solving the above-described conventional problems, and even when a lead-out extension line or the like is provided in the vicinity of the sensing region, by making it less susceptible to influences other than the sensing region, Provided is a capacitance type detection device with improved accuracy of coordinate detection of an object to be detected.

The present invention relates to a sensing region for detecting that a detected object is in contact with or approaching, a plurality of sensor electrodes wired to the sensing region, individual sensor electrodes, and an external device provided outside the sensing region. In a capacitance type detection device comprising: an extension line for routing between the circuit; and a routing area provided in the vicinity of the sensing area and the extension lines densely arranged,
The sensing region and said circumventive and area is covered with a cover sheet, the cover sheet is large towards the thickness of the portion covering the circumventive and area than the thickness of the portion covering the sensing area , the surface of the cover sheet covering the circumventive to region, said raised away from the extension line from the surface of the cover sheet covering the sensing area, the detection object is covering the circumventive by region When contacting or approaching the surface of the cover sheet, it is possible to suppress a change in capacitance formed between the detected object and the extension line,
The cover sheet, wherein the total thickness thin dimension portion covering the sensing area, said circumventive a thickness of thick dimension portion to cover the entire region, are integrally formed of a resin material It is what.

Further , a step is formed on the surface of the cover sheet between the sensing area and the routing area .

  The sensor electrodes include a plurality of X electrodes extending in the X direction and arranged at a predetermined interval in the Y direction, and a plurality of Y electrodes extending in the Y direction and arranged at a predetermined interval in the X direction. They are opposed to each other in a matrix while orthogonal to each other.

In capacitive sensing device of the present invention, since it has to form a thick plate thickness dimension of the lead-out area portion of the cover sheet, the extension line to be wired to the detected body and the lead region The electrostatic coupling between the two can be cut off, and the capacitance can be made difficult to be formed between them.

Alternatively, even if the capacitance is formed, the amount of change with respect to the movement of the detection target can be suppressed small, so that the influence on the detection accuracy can be reduced.
That is, the position detection accuracy as a capacitance type detection device can be increased.

FIG. 1 is a schematic configuration diagram showing a capacitance type detection device, FIG. 2 shows a reference example, a sectional view taken along line II-II in FIG. 1, and FIG. 3 shows an embodiment of the present invention. and is a cross-sectional view similar to FIG. 2.

As shown in FIG. 1, this capacitance type detection device 10 includes a plurality of X electrodes (sensor electrodes) x1, x2,..., Xn extending in the Y direction and arranged at predetermined intervals in the X direction. has also a plurality of Y electrodes arranged at predetermined intervals in the Y-direction extends in the X direction (sensor electrode) y1, y 2, · · ·, and yn.

As shown in FIG. 2, the plurality of X electrodes x1, x2, · · ·, xn is provided on one surface of the dielectric sheet 11 (the surface), the plurality of Y electrodes y1, y 2, · · , Yn are provided on the other surface (back surface) of the dielectric sheet 11. That is, the plurality of X electrodes x1, x2, · · ·, the and xn plurality of Y electrodes y1, y 2, · · ·, via said dielectric sheet 11 is facing opposed to the matrix which are orthogonal to each other and yn ing. Therefore, the X electrodes x1, x2, · · ·, the and xn plurality of Y electrodes y1, y 2, · · ·, the capacitance C is formed between the yn.

An insulating film 12 covering the plurality of X electrodes x1, x2,..., Xn is formed on one surface of the dielectric sheet 11, and similarly below the other surface of the dielectric sheet 11. the plurality of Y electrodes y1, y 2, · · ·, insulating film 13 covering the yn is formed. A cover sheet 15 is fixed to the upper layer of the insulating film 12, and a substrate 14 is fixed to the lower layer of the insulating film 13. The insulating film 12 and the cover sheet 15 are fixed and the insulating film 13 and the substrate 14 are fixed using an adhesive or the like. The insulating films 12 and 13 themselves are adhesives. Also good.

The cover sheet 15 is formed of, for example, a polyester resin, and the surface (the surface on the Z1 side) is an operation surface 15a on which a detection object such as a finger contacts and slides. Wherein the plurality of X electrodes x1, x2, ···, said the xn plurality of Y electrodes y1, y 2, ···, are arranged in a matrix on the position of the lower surface side of the operation surface 15a and yn, As shown in FIG. 1, a portion where the cover sheet 15 is provided is a sensing area A of the capacitance type detection device.

  As shown in FIG. 1, the end portions of the plurality of X electrodes x1, x2,..., Xn are led out from the sensing region A as extensions Xa to the outside on the Y2 side in the drawing. The extension line Xa is densely arranged in a routing area Bx provided adjacent to the sensing area A, and is connected to switching means 21X configured by a multiplexer or the like via the routing area Bx. Yes.

Similarly, end portions of the plurality of Y electrodes y1, y 2 ,..., Yn are led out from the sensing area A to the outside on the X2 side in the drawing as extension lines Ya, respectively, through the routing area By. It is connected to the switching means 21Y.

Said one of the switching means 21Y is connected to the oscillating means 23, said from the oscillating means 23 Y electrodes y1, y 2, · · ·, to yn, it can be selectively apply a predetermined voltage It is like that. An amplifier 24 is connected to the other switching means 21X, and its output is connected to the controller 26 via an A / D converter 25.

  The control means 26 is composed mainly of a CPU, and can not only acquire data from the A / D conversion means 25 but also set the switching timing of the switching means 21X, 21Y, for example. ing.

  The amplification means 24 has a function of amplifying the voltage appearing at the switching means 21X with a predetermined gain, and the A / D conversion means 25 converts the amplified voltage (analog value) into a digital value at a predetermined sampling period. It has a function. In addition, a configuration in which filter means for removing unnecessary noise is provided between the amplifying means 24 and the A / D converting means 25 may be adopted.

The operation of the capacitance type detection device will be described.
The control unit 26 operates the switching unit 21Y and the switching unit 21X, turns on the switch SW1 of the switching unit 21Y, and then sequentially turns on the switches SW1 to SWn on the switching unit 21X side.

Wherein the oscillating means 23 Y electrodes y1, y 2, ···, when a predetermined voltage is inputted to yn, each Y electrodes y1, y 2, ···, arranged in a matrix so as to face the to yn A dielectric flux is generated between each of the X electrodes x1, x2,..., Xn and electrostatic capacitances C are formed, so that the X electrodes x1, x2 are passed through the individual electrostatic capacitances C. ,..., Xn are applied with voltages.

  Here, when a detected object such as a finger is brought into contact with or approached to an arbitrary position on the operation surface 15a of the cover sheet 15, a part of the dielectric bundle is pulled out by the detected object, and in the vicinity of the detected object. The located capacitance is reduced. For this reason, since a part of the capacitance C changes, a voltage corresponding to the change amount is detected from the X electrodes x1, x2,. As for the voltage value detected at this time, a higher voltage value is detected as the distance from the detected object is shorter, and an electrode having a longer distance is detected as a lower voltage value.

  The voltages outputted from the X electrodes x1, x2,..., Xn are inputted to the A / D conversion means 25 through the amplification means 24 and converted into digital data D by the A / D conversion means 25. , The data is sent to the control means 26. Then, the control means 26 determines the position in the X direction on the Y electrode y1 of the detected object from the data D.

Then, the control means 26 sequentially turns on the switches SW2 to SWn of the switching means 21Y, and sequentially turns on the switches SW1 to SWn on the switching means 21X side for each switch SW of the switching means 21Y. wherein Y electrodes y1, y 2, ···, the a yn X electrodes x1, x2, ···, obtains data D at each intersection of xn. The control means 26 determines the coordinate position (coordinate data) of the detected object from these data D.

Here, in the detection apparatus of the reference example shown in FIG. 2 , a shield member 31 as an electrostatic protection means is provided in the routing area By adjacent to the sensing area A. The shield member 31 is formed of a metal plate made of a magnetic material, and is fixed to the surface of the routing area By so as to cover the extension line Ya.

The shield member 31 is at least the preferably configured to cover the vicinity of the object to be detected is close easily the sensing region A, more preferably the Y electrodes y1, y 2, · · ·, the ends of yn extension The line Ya covers the entire length from the position deviating from the sensing area A until it is connected to the switching means 21Y. Note that the shield member 31 is preferably grounded in that a further excellent effect can be expected.

  In this way, by covering the extension portion Ya with the shield member 31, when the detected object approaches the routing area, the area between the detected object and the extension line Ya wired in the routing area By. Thus, no dielectric flux is generated, and it is possible to prevent a capacitance from being formed between the two. Further, even if a capacitance may be formed between the detected object and each extension line Ya, at least the amount of change in the capacitance with respect to the movement of the detected object can be suppressed low.

Therefore, the coordinate data detected by the sensing region A, i.e. X electrodes x1, x2, · · ·, xn and the Y electrodes y1, y 2, · · ·, the coordinate data detected by the yn, lead region The voltages generated by By are not mixed, and even if they are mixed, the value can be made minute, so that the detection accuracy of coordinate data can be improved.

Next, an embodiment of the present invention will be described with reference to FIG.
The configuration of the capacitance type detection means 10 shown in FIG. 3 is substantially the same as the configuration of the reference example . However, the electrostatic protection means provided in the routing area By is different from the shield member 31.

In the embodiment of FIG. 3, of the cover sheet 15, the thickness dimension H2 of the portion corresponding to the lead-out area By, by forming thicker than plate thickness H1 of the operation surface 15a, both during Is provided with a step 15b.

  In this way, by forming the plate thickness dimension H2 of the routing area By thicker than the other part (operation surface 15a), the detected object approaches or contacts the routing area By. In the same manner as described above, it is possible to prevent a capacitance from being formed between the object to be detected and the extension line Ya positioned below the routing area By. Alternatively, even if a capacitance may be formed between the detected object and each extension line Ya, at least the amount of change in the capacitance with respect to the movement of the detected object can be kept low. .

Further, it is only necessary to change the thickness of the cover sheet 15 between the portion of the operation surface 15a corresponding to the sensing area A and the portion corresponding to the routing area By, and the cover sheet 15 is integrally formed of the same member. Therefore, the number of parts is not increased, and the manufacturing cost can be reduced.

Furthermore, since the operator can clearly distinguish the sensing area A and the routing area By, the operability of the capacitive detection device 10 can be improved.

In addition, although the said embodiment demonstrated one routing area | region By, it is the same also about the other routing area | region Bx.

Schematic configuration diagram illustrating a detection apparatus of the electrostatic capacity type, As a reference example of the present invention, a sectional view taken along line II-II in FIG. Sectional view similar to FIG. 2 as an embodiment of the present invention,

10 Capacitance type detection device 11 Dielectric sheet 12, 13 Insulating film 14 Substrate 15 Cover sheet 15a Operation surface 15b Step 21X, 21Y Switching means 23 Oscillating means 24 Amplifying means 25 A / D conversion means 26 Control means 31 Shield member A Sensing area Bx, By Route area Xa, Ya Extension line x1, x2, ..., xn X electrode (sensor electrode)
y1, y2, ..., yn Y electrode (sensor electrode)

Claims (3)

Between a sensing region for detecting that the detected object is in contact with or approaching, a plurality of sensor electrodes wired to the sensing region, individual sensor electrodes, and an external circuit provided outside the sensing region In an electrostatic capacitance type detection device comprising: an extension line for routing that connects the extension line; and a routing area that is provided in the vicinity of the sensing area and in which the extension lines are densely arranged,
The sensing region and said circumventive and area is covered with a cover sheet, the cover sheet is large towards the thickness of the portion covering the circumventive and area than the thickness of the portion covering the sensing area , the surface of the cover sheet covering the circumventive to region, said raised away from the extension line from the surface of the cover sheet covering the sensing area, the detection object is covering the circumventive by region When contacting or approaching the surface of the cover sheet, it is possible to suppress a change in capacitance formed between the detected object and the extension line,
The cover sheet, wherein the total thickness thin dimension portion covering the sensing area, said circumventive a thickness of thick dimension portion to cover the entire region, are integrally formed of a resin material Capacitance type detection device.   The capacitance type detection device according to claim 1, wherein a step is formed on a surface of the cover sheet between the sensing area and the routing area.   A plurality of X electrodes extending in the X direction and arranged at a predetermined interval in the Y direction and a plurality of Y electrodes extending in the Y direction and arranged at a predetermined interval in the X direction are orthogonal to each other. 3. The capacitance type detection device according to claim 1, wherein the capacitance type detection device is opposed to each other in a matrix.

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