JPH0667785A - Conductive tablet material - Google Patents

Abstract

(57) [Abstract] [Purpose] In a conductive tablet material used for an input device for detecting an arbitrary position on the vertical and horizontal axes, the resistance value of each conductive pattern is made the same to eliminate the inconvenience when amplified by a detector. [Structure] By making the line width of a conductive pattern having a long line length thicker than the line width of a conductive pattern having a short line length, the resistance values of the conductive patterns 2a to 2n are made the same. Part of each of the conductive patterns 2a to 2n may be thickened, or the line width may be gradually thickened.
Further, the resistance value of each conductive pattern may be the same by making the layer thickness of the conductive pattern having a long line length thicker than the layer thickness of the conductive pattern having a short line length.
By thus controlling the line width or the layer thickness in each conductive pattern to make the resistance value of each conductive pattern the same, a detection signal of a constant level can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive tablet material used as a touch panel.

[0002]

2. Description of the Related Art A touch panel is an input device capable of touching the screen with a pointing pen or the like while seeing pictures or characters on a panel attached to a display screen, detecting the positions of vertical and horizontal axes, and inputting the coordinate positions thereof. And this touch panel has an optical sensor method, a resistive film method, an electrostatic capacity method,
Although there are various types such as an electromagnetic induction type, the electromagnetic induction type is currently most commonly used.

As a conductive tablet material used in this electromagnetic induction method, conventionally, as shown in FIG. 3, a plurality of conductive patterns 12 are first formed on one surface of a plastic substrate 11 in parallel with the horizontal axis direction. Forming an insulating layer 14 on the
Further, it is known that a plurality of conductive patterns 13 are formed in parallel to the vertical axis direction so as to be orthogonal thereto, and finally an insulating layer 15 is formed. The conductive pattern 12 in the horizontal axis direction of this conductive tablet material is, for example, as shown in FIG. 4, and as shown in the figure, the conductive pattern 12 is formed with the same line width and the same thickness, and is not shown. Similarly, the conductive pattern 13 along the vertical axis is also formed with the same line width and thickness.

[0004]

In the above-mentioned conventional conductive tablet material, since the line width of the conductive pattern and the layer thickness are the same, the resistance value of each conductive pattern is different in proportion to the line length. Therefore, there is a problem that inconvenience occurs when the obtained signal is amplified by the detector.

The present invention has been made in view of the above problems, and an object of the present invention is to eliminate the inconvenience when the resistance values of the respective conductive patterns are made the same and amplified by the detector. Another object of the present invention is to provide a conductive tablet material.

[0006]

The resistance value at both ends of the conductive pattern is proportional to the line length and inversely proportional to the line width and the line thickness. Therefore, in order to make the resistance values of the conductive patterns of different line lengths the same, the line width of the long line length is made larger than the line width of the short line length, or the layer thickness of the long line length is set to the line length. There is a method of increasing the thickness of the layer though it is short. Therefore, in order to achieve the above object, the present invention, in a conductive tablet formed by forming a plurality of conductive patterns so as to be orthogonal to each other, by controlling the line width or layer thickness in each conductive pattern It is characterized in that the resistance values of arbitrary conductive patterns are the same.

[0007]

According to the above-mentioned conductive tablet material of the present invention, since the resistance values of the respective conductive patterns are the same,
A constant level of detection signal is obtained.

[0008]

EXAMPLE FIG. 1 shows a horizontal conductive pattern in the conductive tablet material of the first example. As shown in the figure, in the conductive tablet material 1 of the present embodiment, the line width of the conductive pattern having a long line length is made thicker than the line width of the conductive pattern having a short line length, whereby the conductive patterns 2a to
The resistance values of 2n are the same. That is, each of the conductive patterns 2a to 2n is arranged so that the line width thereof becomes gradually smaller from the longest conductive pattern 2a to the shortest conductive pattern 2n.
Is patterned so that a part thereof becomes thick.

The plastic substrate used in the present invention is made of a material such as polyester or polyimide and has a thickness of 25 to
It is preferably 300 μm. The conductive material forming the conductive pattern is selected from silver, copper and carbon.
One kind or a combination of two or more kinds and a mixture with a synthetic resin binder is used. When silver-based paint is used as the conductive material, migration of silver can be prevented by providing an insulating layer of synthetic resin on the surface of the conductive pattern or coating with carbon-based paint.

In the conductive tablet material 1 of the second embodiment shown in FIG. 2, as in the case of the first embodiment, the line width of the conductive pattern having a long line length is made thicker than that of the conductive pattern having a short line length. By doing so, the resistance values of the conductive patterns 2a to 2n are made the same, but the patterning is performed so that the line widths of the conductive patterns 2a are gradually reduced from the longest conductive pattern 2a to the shortest conductive pattern 2n. ~ 2
At n, the line width is gradually increased.

Although not shown, in the third embodiment, the resistance of each conductive pattern is increased by making the layer thickness of the conductive pattern having a long line length larger than that of the conductive pattern having a short line length. It is also possible to adopt a form in which the values are the same.

Although each conductive pattern is formed by a printing method, it is difficult to accurately change the thickness of the layer of each conductive pattern with one plate. Therefore, it is described in the first to third embodiments. Among these modes, the first and second embodiments in which the resistance value of each conductive pattern is made equal by controlling the line width is preferable.

[0013]

As described above, in the conductive tablet material of the present invention, the resistance value of any conductive pattern is made the same by controlling the line width or layer thickness in each conductive pattern. As a result, a detection signal of a constant level can be obtained, and it is possible to eliminate the inconvenience caused by amplification by the detector.

[Brief description of drawings]

FIG. 1 is a plan view showing a conductive pattern in a horizontal axis direction in a conductive tablet material according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a conductive pattern in a horizontal axis direction in a conductive tablet material according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of a conventional conductive tablet material.

FIG. 4 is a plan view showing a conductive pattern in a horizontal axis direction in a conventional conductive tablet material.

[Explanation of symbols]

 1 Conductive tablet material 2a to 2n Conductive pattern

Claims (1)

[Claims] 1. In a conductive tablet formed by forming a plurality of conductive patterns so as to be orthogonal to each other, the resistance value of an arbitrary conductive pattern is controlled by controlling the line width or the layer thickness in each conductive pattern. Conductive tablet characterized by being the same.