JPH0553714A - Digitizer - Google Patents

Abstract

PURPOSE:To prevent the unevenness of a belt-shaped resistor and also to prevent a positional deviation to a leader line and the disconnection of a leader line for a digitizer provided with a belt-shaped resistor and a stripe electrode. CONSTITUTION:The stripe electrode 18 is printed on a belt-shaped resistor 17 so that the uneven printing state of the resistor 17 printed precedently is eliminated. At the same time, the electrodes 16 are formed at both ends of the resistor 17 for the application of voltage. These electrodes 16 are formed with the same printing plate and in the same process as the electrode 18. Furthermore a leader line is formed with the same printing plate as and in the same process the electrode 18 to secure the electrical connection to another circuit. Meanwhile the resistor 17 is printed at a position under the joint part between the leader line and the electrode 18. So that the joint part is reinforced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called digitizer used as an input device for handwritten characters and figures, and particularly when a figure is input to a computer or only a partial area of a printed matter by a copy machine. The present invention relates to a digitizer provided with a coordinate input sheet used when specifying each coordinate input data to specify and copy.

[0002]

2. Description of the Related Art As a conventional digitizer, for example, there is a digitizer disclosed in Japanese Patent Laid-Open No. 61-104513. In this case, it is necessary to form a uniform strip-shaped resistor by applying a resistance film on an insulating substrate, applying coating using a mask, printing, vapor deposition, sputtering, and the like.

Another conventional example is Japanese Patent Laid-Open No.
In the digitizer using the coordinate input sheet disclosed in Japanese Patent No. 2-184512, two coordinate input sheets 1A and 1B are provided as shown in the principle diagram of FIG.
Each of the coordinate input sheets 1A and 1B has electrodes 2 and 3 facing each other at both ends of an insulating sheet, and a surface resistance 4 is formed between the electrodes. These two coordinate input sheets 1A and 1B are vertically arranged, respectively. The electrode directions are overlapped with each other by 90 degrees, and they are used, for example, for detecting the X-coordinate position of the contact point for pressing the lower coordinate input sheet 1B and for detecting the upper coordinate input sheet 1A.

That is, when the coordinate input sheet 1A is brought into contact with an arbitrary point P in FIG. 4, a voltage 5A is applied to the upper coordinate input sheet 1A, so that sheet 1A
The partial pressure at the finger contact input point P at is extracted from the partial pressure output end 6 of the lower coordinate input sheet B as X-axis coordinate position data. Next, the voltage 5B for the lower coordinate input sheet 1B
Of the fingertip input point P on the sheet 1B
From the partial pressure output end 7 of the upper coordinate input sheet 1A to Y
It is taken out as axial coordinate position data, and the position on the XY coordinate of the finger input point P is obtained by such time division.

[0005]

However, such a conventional digitizer has a problem that coordinates cannot be accurately input due to printing unevenness of the band-shaped resistor.

That is, considering the finger contact input point partial pressure of the upper coordinate input sheet 1A, if the linearity of the surface resistance 4 between the electrodes 2 and 3 is ensured, the potential difference between the electrodes (for example, 5).
In contrast to V), the finger contact input point partial pressure shows a value inversely proportional to the separation from the + electrode 2. That is, assuming that the finger input point P is at the intermediate position between the electrodes 2 and 3, it should show 2.5V.

However, in actuality, the surface resistance 4 is affected by printing unevenness and the like and does not exhibit accurate resistance linearity. Therefore, the 2.5V line is a curved line with respect to the original position of the chain line in FIG. As a result, even though the input person correctly points to the intermediate point, there are many cases in which coordinate data deviating from that point is input. This is the lower coordinate input sheet 1
The same applies to B.

Further, not only the uneven printing, but also the positional deviation between the sheet resistance 4 and the lead line causes an error in the detected coordinate data.

Further, since the lead wire is attached later in a separate process from the input sheet, the work process is complicated, and the lead wire is easily broken.

The present invention has been made in order to overcome the drawbacks of the prior art, and an object thereof is to provide a digitizer having high coordinate input accuracy.

[0011]

According to a first aspect of the present invention, there is provided a digitizer in which two sheets of strip-shaped resistors and striped electrodes are arranged in a direction in which the strip-shaped resistors of the respective sheets are alternately perpendicular to each other. A digitizer laminated in layers, characterized in that a printed layer of stripe-shaped electrodes is provided on a printed layer on which a strip-shaped resistor is printed.

A digitizer according to a second aspect of the present invention is characterized in that the strip-shaped resistor has electrodes for applying a voltage at both ends, and the electrode and the stripe-shaped electrode are formed by the same printing plate.

A digitizer according to a third aspect of the present invention is characterized in that the lead-out line for electrically connecting with an external circuit and the striped electrode are formed on the same printing plate.

A digitizer according to a fourth aspect is characterized in that a strip-shaped resistor is formed by printing on a lower portion of the lead-out portion of the striped electrode to which the lead-out line is connected.

[0015]

In the digitizer having the structure according to the first aspect of the present invention, the striped electrodes are formed by printing on the strip-shaped resistor to prevent uneven printing of the strip-shaped resistor to be printed first.

In the digitizer having the structure of claim 2,
Electrodes for voltage application are formed at both ends of the strip resistor,
The electrodes are formed in the same step by the same printing plate as the striped electrodes.

In the digitizer having the structure of claim 3,
Lead lines for making electrical connection with other circuits are formed in the same step by the same printing plate as the striped electrodes.

In the digitizer having the structure of claim 4,
A strip-shaped resistor is printed on the lower portion of the connection portion between the lead line and the stripe voltage to strengthen the connection portion.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the digitizer according to the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit block diagram showing the configuration of an embodiment of the digitizer according to the present invention. As shown in FIG. 1, the digitizer of the present invention is arranged 90 ° orthogonally.
Coordinate input sheets 10A, 10B for X and Y coordinates,
Switching circuits 11, 12, and 13 connected to the coordinate input sheets 10A and 10B, and A for converting analog signals of X and Y coordinates input from the switching circuit 12 into digital signals.
The A / D converter 14 and a CPU 15 connected to the A / D converter 14 are roughly configured. The uniform resistors 17, 17 which are strip-shaped resistors of the coordinate sheets 10A, 10B are each divided into four by five drive electrodes 16, and switching is performed so that the voltage Vcc is separately applied between the drive electrodes. The contacts a to d of the circuits 11 and 13 are provided.

The voltage application contacts A and D of the switching circuits 11 and 13 are connected so as to be supplied with a voltage Vcc (5 [V] in this embodiment), and a ground contact B for grounding,
E is provided. The switching circuits 11 and 13 have a switch 1 which is opened and closed under the control of the CPU 15.
1a, 11b and 13a, 13b are provided.

In the switching circuit 12, the input points of the coordinate input sheets 10A and 10B for detecting the positions of the X and Y coordinates by the pen or the pressed finger are individually obtained.
A switch 12a for selecting the contacts a, b, c, d for the coordinate input information from the coordinate input sheets 10A, 10B and the voltage information applied to each block under the control of the CPU 15 is provided. This is a contact for analog signal input.

Further, the coordinate input sheet 10A detects a pressing input point having a Ly width on the Y-axis, and the coordinate input sheet 1
0B is configured to detect a pressing input point of LX width on the X axis.

Further, in the drawing, 18, ... Are silver stripe electrodes.

FIG. 2 shows the coordinate input sheets 10A and 1 of FIG.
0B is an enlarged view of a main part of FIG.
a, and the lead portion 18a serves as a connection point for connecting to the lead wire 20 for supplying a voltage. A protruding portion 17a, which is a partial protrusion of the strip-shaped resistor 17, is formed below the lead-out portion 18a. Then, the striped electrodes 18 are provided on the printed strip resistors 17.

FIG. 3 shows coordinate input sheets 10A, 1 of FIG.
2B is an enlarged view of another main part of FIG. 0B, in which drive electrodes 16 formed by the same printing plate as the striped electrodes 18 are provided at both ends of the strip-shaped resistor 17.
A lead line 20 formed from the same printing plate is also drawn out from 6.

That is, since the striped electrodes 18, the lead-out portions 18a, and the drive electrodes 16 are formed on the same printing plate after the strip-shaped resistors 17 are printed, the strip-shaped resistors 17 to be printed first have unevenness. Is almost eliminated, and a uniform resistor can be formed.

The drive electrodes 16 on both ends of the strip-shaped resistor 17 serve as the reference for the input coordinates, but the drive electrodes 16 and the stripe-shaped electrodes 1 connected to the lead lines 20 are connected.
Since the eight drawn-out portions are formed by the same printing plate, the positional deviation between the two is unlikely to occur, and the coordinate detection error due to the positional deviation between the both can be prevented.

Furthermore, since the lead lines 20 and the striped electrodes 18 are formed in the same printing plate and in the same process, the number of manufacturing processes can be reduced.

Further, since the protruding portion 17a protruding from the strip-shaped resistor 17 is formed below the lead-out portion 18a of the striped electrode 18, the connection portion which is easily broken is reinforced.

[0031]

As described above, according to the digitizer of the first aspect, since the printed layer of the striped electrodes is formed on the strip-shaped resistor, the strip-shaped resistor can be formed uniformly. You can expect correct coordinate detection output.

Further, according to the digitizer of the second aspect, since the drive electrode and the striped electrode of the strip-shaped resistor are formed by the same printing plate, the work process is completed in one step, and the positional deviation between them is caused. Can be prevented, and the error in the coordinate detection output due to the displacement can be reduced.

Further, according to the digitizer of the third aspect, since the lead line and the striped electrode are formed by the same printing plate, one working step is required and the manufacturing cost can be suppressed.

Further, according to the digitizer of the fourth aspect, the strip-shaped resistor is formed below the connecting portion between the lead wire and the stripe electrode, so that the lead wire is prevented from being broken at the lead portion. You can

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing an embodiment of a basic circuit configuration relating to a digitizer of the present invention.

FIG. 2 is an enlarged view of a main part showing the configuration of an embodiment of the coordinate input sheet of the digitizer of the present invention.

FIG. 3 is another enlarged view of the essential parts showing the configuration of an embodiment of the coordinate input sheet of the digitizer of the present invention.

FIG. 4 is a principle diagram of a digitizer using a conventional coordinate input sheet.

FIG. 5 is a plan view of a conventional coordinate input sheet.

[Explanation of sign]

 10A, 10B Coordinate Input Sheet 16 Drive Electrode 17 Strip Resistor 17a Projection 18 Stripe Electrode 18a Leader 20 Leader

Claims (4)

[Claims] 1. A digitizer in which two sheets each composed of a strip-shaped resistor and a striped electrode are laminated in layers in a direction in which the strip-shaped resistors of the respective sheets are alternately orthogonal to each other, wherein the strip-shaped resistor is printed. A digitizer, wherein the printed layer of the striped electrode is provided on the printed layer. 2. The digitizer according to claim 1, wherein the strip-shaped resistor has electrodes for applying a voltage at both ends, and the electrode and the striped electrode are formed by the same printing plate. 3. The digitizer according to claim 1, wherein the lead-out line for electrically connecting to an external circuit and the striped electrode are formed by the same printing plate. 4. The strip-shaped resistor is printed on the lower portion of the lead-out portion of the striped electrode to which the lead-out line is connected.
Digitizer described.