JP2002007050A - Device for inputting coordinates - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinates input device which reduces cost in the process of forming insulation spacers for erroneous input prevention and also improves resolution. SOLUTION: This coordinates input device is provided with a configuration where a resistor 4, an upper electrode plate 3 having a pair of electrodes 20 being in contact with the resistor 4 and a lower electrode plate 7 having a resistor layer 6 and an insulation print layer 5 pasted together with the surface of the respective resistors arranged on an inner side. The lower electrode plate 3 has the insulation spacers 8A formed on the resistor layer and the spacers 8A are composed of water and oil repellent insulation resin powders.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device used as a pointing device of a computer, and more particularly to a structure provided with an insulating spacer for preventing erroneous input of the coordinate input device.

[0002]

2. Description of the Related Art When a surface of a flat plate is designated by a coordinate indicator such as a pen or a finger, or a designated point is moved to draw a trajectory, a corresponding coordinate position on a computer display is displayed by a cursor or the cursor is moved. A coordinate input device in which a locus is drawn is generally used as a tablet.

FIG. 4 shows a partial sectional structure of a conventional coordinate input device.
Shown in However, the actual shape of the coordinate input device is a rectangular flat plate. As shown in FIG.
Are, in order from the operation surface 102, an upper electrode plate 103, a carbon resistor 104, an insulating printed layer 105, an insulating spacer 108,
It comprises a carbon resistor 109 and a lower electrode 107. The upper electrode 103 and the lower electrode 107 are connected to a flexible printed board (Flexible) via a transfer section.
Print Circuit). still,
Reference numeral 111 indicates a tip portion of a pen-shaped coordinate indicator.

The coordinate input device 101 of the present embodiment is
A method of detecting the position when the button 11 is pressed and operated will be briefly described below with reference to FIGS. 5 and 6, the same components as those shown in FIG. 4 are denoted by the same reference numerals as those in FIG. 4, and the description thereof will be omitted or will be briefly described.

FIG. 5 is a diagram simply illustrating the principle of position detection in the X and Y directions of the coordinate input device 101 of the present embodiment by superimposing two electrode plates and a resistance circuit.
1 is disassembled into an upper electrode plate 116 and a lower electrode plate 117, and shows a state in which an X-direction resistance circuit 119 is overlaid on the lower electrode plate 117 and a Y-direction resistance circuit 118 is overlaid on the upper electrode plate 116. 5A shows a state in which a voltage is applied to the upper electrode plate 116 when the coordinate input device is pressed by the coordinate indicator 111, and FIG. 5B shows a state in which the lower electrode plate 1
17 shows a state where a voltage is applied. FIG. 6 is a simple equivalent circuit of the coordinate input device 101 of the present example. The resistance circuit 119 in the X direction, the resistance circuit 118 in the Y direction, the XY switch 122, and the A / D converter 120 in the coordinate input device 101 are provided. Etc.

In a state where the center point A of the operation surface of the coordinate input device 101 shown in FIG.
When a voltage in the Y direction is applied to the upper electrode plate 116 of the two electrode plates constituting the coordinate input device 101 shown in FIG.
An output corresponding to the position of the center point A in the X direction from the lower electrode plate 117 is obtained. By switching the voltage application surface and applying a voltage in the X direction to the lower electrode plate 117 as shown in FIG.
An output corresponding to the position of the point A in the Y direction is obtained from the upper electrode plate 116. On the other hand, in the equivalent circuit shown in FIG. 6, when the position in the X direction is detected, the switch 1
23, 124, 127 are ON, switches 125, 126
Is OFF, and conversely, when detecting the position in the Y direction, the switches 125, 126, 128 are ON and the switches 123, 124 are OFF.

Each output is recognized as positional information by a CPU (Central Processing Unit) (not shown) via an A / D converter 120. The resolution of the coordinate input device of this example depends on the resolution of the A / D converter 120. For example, the resolution of the A / D converter 120 shown in FIG.
If 0 bits (210 = 1024), the position information when the center point A on the coordinate input device 101 is pressed is the middle point of the area divided into 1024 in the XY directions. 512 is output from the A / D converter 120.

By the way, in the coordinate input device 101 of the present embodiment which operates on the above principle, it is necessary to keep a constant interval between the upper and lower electrode plates when not operating, and to prevent erroneous input due to unnecessary contact. Therefore, the insulating spacer 10 shown in FIG.
After the carbon resistor 109 is printed on the lower electrode plate 107, an insulating paste is applied on the carbon resistor 109 to a diameter of 50 to 100 μm (10 ⁻⁶ m) and a height of 10 to 100 μm (10 ^In addition to the method of printing in the form of a dot of ⁻⁶ m), a method of forming a pressure-sensitive conductive resin in the form of a dot or a plate on the carbon resistor to form an insulating spacer is known.

[0009]

However, the above-described insulating spacer forming method has the following problems.
In the method of printing an insulating paste on the resistor after printing the carbon resistor, a printing process for forming the insulating spacer is required, which increases the man-hours and increases the printing process. Since the preferable diameter of the insulating spacer is as large as 50 to 200 μm (10 ⁻⁶ m), there is a problem that the number of non-conductive portions on the electrode plate is increased and the resolution of the coordinate input device is reduced. In the method of forming the pressure-sensitive conductive resin as the insulating spacer, there is a problem that the process for forming the insulating spacer is necessary, and that it is difficult to adjust the pressure of the coordinate input device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a coordinate input device in which the cost in the step of forming an insulating spacer is reduced and the resolution is improved.

[0011]

In order to achieve the above object, the present invention employs the following constitution. The coordinate input device of the present invention includes a first electrode plate including a resistor, a pair of electrodes connected to the resistor, and a circuit derived from the electrode, a resistor, a pair of electrodes, and a circuit. A second electrode plate attached to the first and second substrates with the surfaces of the resistors facing each other, and at least one of the first and second substrates is an insulating spacer formed on the resistor; Has,
The insulating spacer is made of a water- and oil-repellent insulating resin.

In the coordinate input device according to the present invention, the resistor and the insulating spacer can be formed simultaneously by using a water- and oil-repellent insulating resin powder as the insulating spacer. This is because, in the coordinate input device according to the present invention, since the formation of the resistor is performed using a printing paste obtained by mixing a water- and oil-repellent insulating resin powder with conductive ink, the printing paste is printed on a substrate. This is because the insulating resin powder and the conductive ink are repelled by the water and oil repellency of the insulating resin powder, and the insulating resin powder is exposed on the resistor to form an insulating spacer.

That is, in the coordinate input device according to the present invention, since the insulating spacer is formed simultaneously with the printing of the resistor, the step of forming the insulating spacer can be omitted. Can be.

In the present invention, a water-repellent and oil-repellent insulating resin powder having an arbitrary particle diameter can be used as the insulating spacer, so that a spacer having a diameter of, for example, 10 μm (10 ⁻⁶ m) can be formed. . That is, the number of non-conductive portions on the electrode surface is reduced, and the resolution of the coordinate input device can be improved.

As the water- and oil-repellent insulating resin powder, it is preferable to use a silicon resin or a silicon fluoride resin in addition to a fluorine resin such as ethylene tetrafluoride and ethylene trifluoride.

The average particle size of the water- and oil-repellent insulating resin powder is preferably at least twice as large as the thickness of the resistor formed simultaneously. This is because if the particle size is smaller than twice the thickness of the resistor, the difference in height from the surface of the resistor is too small to function as an insulating spacer.
However, when the particle size is more than three times larger, the coordinate input device operation surface is pressed by a coordinate indicator such as a pen or a finger because a distance between two electrode plates constituting the coordinate input device is increased. In this case, the deformation amount of the electrode plate becomes unnecessarily large, and the operational feeling of the coordinate input device is impaired. Therefore, the particle size of the insulating resin powder is preferably set to be two to three times the film thickness of the resistor. preferable.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to the embodiment described below. FIG. 1 is a cross-sectional view of the coordinate input device 1 of the present embodiment, and FIG. 2 is a perspective view showing a state where the coordinate input device 1 of the present embodiment is disassembled. 2 that are the same as those in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and the description thereof will be omitted or briefly described.

As shown in FIG. 1, a coordinate input device 1 of the present embodiment has an upper electrode plate (first electrode plate) 3 having a resistor 4 made of carbon and an electrode 20 formed on a film substrate.
And a lower electrode plate (second electrode plate) 7 in which a resistor layer 6 and an insulating printed layer 5 are formed on a glass substrate, with the surface of the resistor 4 and the surface of the resistor layer 6 facing each other. This is a configuration in which they are bonded together. Reference numeral 11 denotes a tip portion of a pen-shaped coordinate indicator.

FIG. 2 is a perspective view showing a state in which the tablet 1 of the present embodiment is disassembled into an upper electrode plate 3, an insulating printed layer 5, and a lower electrode plate 7. As shown in FIG. 2, the upper electrode plate 3 includes
An electrode 20a is arranged along two sides parallel to each other of the upper electrode plate, and a circuit 21 derived from the metal electrode 20a
a is connected to a transfer section 22a provided near the notch for inserting the FPC 10. The electrodes 20b of the lower electrode plate 7 are arranged along two sides of the lower electrode plate 7 orthogonal to the sides of the upper electrode plate 3 where the electrodes 20a of the upper electrode plate 3 are arranged. Derived circuit 2
1b is connected to a connection terminal to the FPC 10.
The arrangement structure of the electrodes 20a and 20b shown in FIG. 2 is an example, and the arrangement structure or shape of the electrodes 20a and 20b is not limited to that shown in FIG.

The resistor layer 6 shown in FIG. 1 comprises a water / oil repellent insulating resin powder 8 and a layered resistor 9 made of carbon. The insulating resin powder 8 is contained in the resistor 9. Although it is in a buried state, as shown in FIG. 1, the upper portion 8a of the insulating resin powder 8 is exposed on the resistor 9, and the exposed upper portion 8a connects the resistor 4 and the resistor 9 to each other. It insulates and functions as an insulating spacer 8A.

Next, a manufacturing process of the resistor layer 6 including the insulating resin powder 8 and the resistor 9 of the coordinate input device 1 of the present embodiment shown in FIG. 1 will be described with reference to FIG. 3A shows a state immediately after the resistor is printed, and FIG. 3B shows a state after the resistor is printed.
FIG. 3 is a partial cross-sectional view in which a state where an upper portion of an insulating resin powder 13 is exposed is partially enlarged. First, a water- and oil-repellent insulating resin powder 13 such as tetrafluoroethylene is mixed and stirred with the conductive ink 14 to produce a printing paste 16 for printing the resistor layer 6 on the substrate 15. Insulating resin powder 1
It is preferable that the particle size of 3 is about 2 to 3 times the desired film thickness of the resistor 9. That is, since the thickness of the resistor 9 is preferably 5 to 15 μm (10 ⁻⁶ m), the diameter of the insulating resin powder 13 is 10 to 40 μm (1
0 ^-6 m).

Using the printing paste 16, the substrate 15
When the resistor printing is performed thereon, the printing paste 16 on the substrate immediately after printing is in a state shown in FIG. 3A. At this time, the printing paste 16 is in a liquid state, and the insulating resin powder 13 is in a state of being taken in the conductive ink 14. However, the insulating resin powder 13 is water-repellent and oil-repellent, and the particle size of the insulating resin powder 13 is larger than the film thickness of the resistor 9 formed by drying the conductive ink 14. The resin powder 13 repels the conductive ink 14 to form the insulating resin powder 1.
3 is exposed on the conductive ink 14 to obtain the state shown in FIG. 3B. In some cases, the conductive ink 14
The insulating resin powder 13 rises above, and the insulating resin powder 13
Is exposed. Thereafter, the conductive ink 14 is dried and solidified to form the resistor layer 6 shown in FIG. 1, and the insulating resin powder 8 fixed in the resistor 9 is formed as an insulating spacer 8A.

The water-repellent and oil-repellent insulating resin powder 13 used for the printing paste 16 is, for example, a fluorine-based resin powder such as ethylene tetrafluoride or ethylene trifluoride, or a silicon-based or silicon fluoride-based resin powder. be able to. The water- and oil-repellent insulating powder 13 has a particle size of 1
The thickness is preferably 0 to 40 μm (10 ⁻⁶ m), but is not limited to the above range, and can be appropriately changed depending on the desired film thickness of the resistor 9.

Further, in this embodiment, an example using a carbon resistor is shown, but ITO (Indium Tin) is used.
Oxide) can be used. In the present embodiment, the substrates used for the upper electrode plate 3 and the lower electrode plate 7 are a film substrate and a glass substrate, respectively. However, other combinations are also applicable. For example, a film substrate and a film substrate, a glass substrate And a glass substrate.

Further, in the present embodiment, an example is shown in which the resistor layer 6 including the insulating spacer 8A is provided only on the lower electrode plate 7, but the resistor layer including the insulating spacer is provided only on the upper electrode plate 3. It is also possible to adopt a configuration provided, or a configuration provided on both the upper electrode plate 3 and the lower electrode plate 7.

In the present invention, since the resistor layer 6 composed of the resistor 9 and the insulating spacer 8A is formed using the printing paste 16 in which the insulating resin powder 13 is mixed in the conductive ink 14, the desired height can be easily obtained. An insulating spacer 8A having a high density can be obtained. This is because the height of the insulating spacer 8A can be adjusted by the particle size of the insulating resin powder 13 and the density of the insulating spacer 8A can be adjusted by the amount of the insulating resin powder 13 contained in the printing paste 16. is there. Further, since the insulating resin powder 13 is mixed with the liquid conductive ink 16, the insulating resin powder 13 at the time of application is applied.
And the insulating spacers 8A uniformly distributed on the resistor 9 can be easily obtained.

[0027]

As described above in detail, according to the present invention, a resistor and an insulating spacer are simultaneously formed on a substrate by using a water- and oil-repellent insulating resin powder for the insulating spacer of the coordinate input device. Therefore, the cost can be reduced by omitting the insulating spacer printing step.

In addition, since the insulating resin powder is used as the insulating spacer, the diameter of the spacer can be reduced, and the non-conductive portion on the electrode surface of the coordinate input device is reduced, so that the resolution of the coordinate input device is improved. Can be.

Further, since the insulating spacer is formed by using a printing paste obtained by mixing a water- and oil-repellent insulating resin powder with a conductive ink, the height and density of the insulating spacer are determined by the particle size and the amount of the insulating resin powder mixed. Can be adjusted, and since the dispersion of the insulating resin powder is good, an insulating spacer having a uniform distribution on the resistor can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a partial cross-sectional structure of a coordinate input device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an exploded state of a coordinate input device according to an embodiment of the present invention.

FIG. 3A is a partial cross-sectional view showing a state immediately after printing a print paste on a substrate, and FIG. 3B is a partial cross-sectional view showing a state where the print paste is dried and solidified. .

FIG. 4 is a partial cross-sectional structure diagram showing an example of a conventional coordinate input device.

FIG. 5 is a circuit diagram schematically showing the state of input to the coordinate input device and detection of position information, and FIG.
FIG. 5B shows a state where the position in the Y-axis direction is detected.

FIG. 6 is a diagram showing a simple equivalent circuit of the coordinate input device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 coordinate input device 2 operation surface 3 upper electrode plate (first electrode plate) 4 resistor 5 insulating printed layer 6 resistor layer 7 lower electrode plate (second electrode plate) 8, 13 insulating resin powder 8A insulating spacer 10 FPC 11 Coordinate indicator 12 Housing frame 14 Conductive ink 15 Substrate 16 Print paste 20a, 20b Electrode 21a, 21b Circuit 22a, 22b Transfer unit

Claims (5)

[Claims] 1. A first electrode plate having a resistor, a pair of electrodes connected to the resistor, and a circuit derived from the electrode, and a second electrode having a resistor, a pair of electrodes, and a circuit. An electrode plate has a configuration in which the surfaces of resistors are bonded together with the surfaces of the resistors inside, and at least one of the first and second electrode plates has an insulating spacer provided on the resistor. ,
A coordinate input device, wherein the insulating spacer is made of a water- and oil-repellent insulating resin powder. 2. The coordinate input according to claim 1, wherein the insulating spacer is made of the water- and oil-repellent insulating resin powder at least partially exposed on a resistor of an electrode plate having the insulating spacer. apparatus. 3. A method according to claim 1, wherein the resistor of the electrode plate having the insulating spacer is formed using a conductive ink mixed with a water- and oil-repellent insulating resin powder.
Or the coordinate input device according to 2. 4. The coordinate input device according to claim 1, wherein the water- and oil-repellent insulator powder is any one of a fluororesin, a silicon resin, and a silicon fluoride resin. . 5. The method according to claim 1, wherein the average particle diameter of the water- and oil-repellent insulator powder is at least twice as large as the thickness of the resistor of the electrode plate having the insulating spacer.
The coordinate input device according to any one of claims 1 to 4.