JPH1124827A - Coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinate input device which can minimize an input unable area where a pushed position cannot be detected and also can stably operate despite its miniaturization by forming a fine dot space at the center part of an insulating film and reducing gradually the fineness of the dot space toward the fringe part of the insulating film. SOLUTION: An insulating film 4 is positioned at a lower side with its rear face side stuck to a reinforcing plate, etc., and has plural dot spacers 12 formed on a resistance film 41. The spacers 12 made of an insulating material such as the photo-curing resin, etc., have different spaces according to their positions. That is, the spacers 12 are finely placed at the center part of the film 4 and this fineness is gradually reduced toward the fringe part of the film 4. For instance, the spacers 12 are arranged on the concentric circles set based on the center of the film 41 with fine spaces set near the film 41 and the rough spaces set gradually toward the fringe part of the film 41 respectively.

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 which is incorporated in an information processing device or the like and generates coordinate information of a position pressed by a pen tip or a fingertip. The present invention relates to a coordinate input device that operates stably even when the area is minimized and miniaturized.

2. Description of the Related Art In recent years, as a means for inputting character information or coordinate information in a portable information processing device or the like in which it is difficult to employ a keyboard, a mouse, or the like, for example, an operator touches a pen tip or a fingertip to input character information or coordinate information. A coordinate input device capable of inputting is employed.

[0003] The principle of such a coordinate input device is, for example, that a plurality of dot spacers made of an insulator are opposed to each other.
When the touch panel is touched with a pen tip or a fingertip, the pressed resistive film comes into contact with the other resistive film, and a voltage corresponding to the coordinate value of the pressed point is output.

However, there is an input-disabled area around the dot spacer made of an insulator where the resistance film is not electrically connected when pressed, and, for example, the coordinates of the pressed point when the touched pen tip is slid as it is. The output voltage corresponding to the value becomes discontinuous.

In a coordinate input device having a large area, the ratio of the non-input area to the entire area is small and the existence of the non-input area is not a problem. However, as the coordinate input apparatus is downsized, the arrangement pitch of the dot spacers is reduced. The presence of the non-input area greatly affects the characteristics.

[0006] Therefore, a non-input area in which the pressed position cannot be detected is minimized, and there has been a demand for the development of a coordinate input apparatus that operates stably even when the apparatus is downsized.

[0007]

2. Description of the Related Art FIG. 9 is a perspective view showing a conventional coordinate input device. In the figure, a coordinate input device has insulating films 1 and 2 each having a resistive film 11 or 21 made of carbon or the like adhered to one side, and two insulating films 1 and 2
They face each other via a spacer 3 surrounding the work area so that the insides 1 and 21 are inside.

The insulating film 1, which is located on the lower side and whose back surface is adhered to the reinforcing plate 6 or the like, has a plurality of dot spacers 12 formed on a resistive film 11, and a conventional coordinate input device uses a photocurable resin. A plurality of dot spacers 12 are arranged at equal intervals regardless of the position.

Although not shown, electrodes are formed so that currents are orthogonal to each other along two opposing sides of the resistance films 11 and 21, and the upper insulating film 1 is formed by a pen or a fingertip.
Is pressed, the resistance films 11 and 21 are short-circuited, and a voltage corresponding to the coordinates of the pressed point is output.

[0010]

However, in the coordinate input device having the above structure, a plurality of dot spacers made of an insulator are interposed between two opposed resistive films. There is an input-disabled area where the resistance films are not electrically connected even when pressed.

In the non-input area, even when pressed with a pen tip or the like, a voltage corresponding to the coordinates of the pressed point is not output because the resistance films are not electrically connected. For example, when the touched pen tip is slid as it is. The output voltage corresponding to the coordinate value of the pressed point becomes discontinuous.

In a coordinate input device having a large area, the ratio of the non-input area to the entire area is small, and the existence of the non-input area does not matter. However, as the arrangement pitch of the dot spacers is reduced, the existence of the non-input area is reduced. However, there is a problem that characteristics greatly affect the characteristics.

It is an object of the present invention to provide a coordinate input device in which a non-input area where a pressed position cannot be detected is minimized, and which operates stably even when the apparatus is downsized.

[0014]

FIG. 1 is a perspective view showing a coordinate input device according to the present invention. The same object is denoted by the same symbol throughout the drawings.

The above-mentioned problem is solved by two insulating films 4 and 5 having resistive films 41 and 51 respectively attached to one side and facing each other with the resistive films 41 and 51 inside, and one insulating film 4
And a plurality of dot spacers 12 formed on the resistive film 41 to form a gap between the resistive films 41 and 51.
Is achieved by the coordinate input device of the present invention, which is arranged densely at the center of the insulating film 4 so as to be gradually sparser from the center to the periphery.

In the coordinate input device, the ratio of the non-input area to the entire area depends on the interval between the dot spacers and the pressure at the time of pressing, and the entire area is increased with the increase of the interval between the dot spacers or the pressure at the time of pressing. The proportion of the non-inputable area occupied decreases.

On the other hand, according to experiments, the mechanical input resistance when inputting coordinate information by pressing down the insulating film on which the spacer is adhered is the smallest near the center of the insulating film and is small from the vicinity of the center to the periphery. There is a tendency to gradually increase as the part approaches.

In the coordinate input device of the present invention, the dot spacers are densely arranged in the center of the insulating film which has a small input resistance and can be easily pressed, and is directed to the peripheral portion where the input resistance increases and the pressure at the time of pressing becomes difficult to increase. The dot spacers are arranged so as to be sequentially sparse.

As described above, by disposing the dot spacers densely at the center of the insulating film and by arranging the dot spacers so as to be gradually sparse from the center to the periphery, the input impossible area occupying the whole area is obtained. Can be minimized.

That is, the non-input area where the pressed position cannot be detected is minimized, and a coordinate input device that operates stably even when the size is reduced can be realized.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. 2 is a view showing experimental data by the inventors, FIG. 3 is a view for explaining the principle of arrangement of dot spacers, FIG. 4 is a view showing a second embodiment of the present invention, and FIG. FIG. 6 is a diagram showing a fourth embodiment of the present invention, FIG. 7 is a diagram showing a first means for eliminating an input impossible area, and FIG. 8 is a second means for eliminating an input impossible area. It is a figure showing a means.

As shown in FIG. 2 (a), two insulating films opposing each other such that the resistive film is on the inner side are attached to both sides of a spacer having an inner diameter of 32 mm, and a dot spacer arranged at the center is provided. When an area delimited by 12 is depressed, an input impossible area s is generated as shown in FIG.

In the coordinate input device, the ratio of the non-input area s to the entire area S differs depending on the interval between the dot spacers and the pressure at the time of pressing, and is based on experiments conducted by the inventors while changing the interval of the dot spacers and the pressing force. Fig. 2 (c)
The ratio changes as shown in FIG.

For example, if the interval between the dot spacers is about 6 mm, as shown by the broken line, the ratio of the non-inputable area is about 10% with a pressing force of about 15 g, and if the interval between the dot spacers is about 8 mm, as shown by the one-dot chain line. With a pressing force of about 10 g, the ratio of the non-inputtable area becomes about 10%.

On the other hand, the mechanical input resistance at the time of inputting coordinate information by pressing down the insulating film with the spacer attached on the periphery is the smallest near the center of the insulating film as shown in FIG. It increases rapidly as it approaches the periphery from near the center.

Therefore, even if the interval between the dot spacers arranged as shown in FIG. 3B is small in the vicinity of the center where the input resistance is small, a large force can be applied at the time of pressing, and the input occupying the whole area can be applied. 10% of unusable area
It can be suppressed to the following.

Further, by expanding the interval between the dot spacers as shown in FIG. 3 (b) at the peripheral portion where the input resistance sharply increases, even if the force that overcomes the input resistance and contributes to pressing is reduced, the entire area is reduced. The percentage of non-enterable areas
It can be suppressed to 10% or less.

As shown in FIG. 1, the coordinate input device according to the present invention has insulating films 4, 5 on which resistance films 41, 51 made of carbon or the like are adhered, and the two insulating films 4, 5 are resistance films. They face each other via a spacer 3 surrounding the work area so that 41 and 51 are inside.

The insulating film 4, which is located on the lower side and whose back surface is adhered to a reinforcing plate or the like, has a plurality of dot spacers 12 formed on the resistive film 41 and is made of an insulator such as a photo-curable resin. The distance between the dot spacers 12 differs depending on the position based on the concept shown in FIG.

That is, in the coordinate input device according to the present invention, the plurality of dot spacers 12 are arranged so as to be dense at the center of the insulating film 4 and, at the same time, become sparser from the center of the insulating film 4 to the periphery. Dot spacers 12 are arranged as described above.

As described above, the dot spacers are densely arranged at the center of the insulating film, and the dot spacers are arranged so as to be gradually sparser from the center to the periphery, so that the input impossible area occupying the whole area is reduced. Can be minimized.

In the first embodiment of the present invention, as shown in FIG. 1, a plurality of dot spacers 12 are arranged on a concentric circle centered on the center of the resistive film 41, and the concentric circles are spaced near the center of the resistive film 41. Are formed so that the distance from the center to the peripheral portion becomes smaller gradually.

In the second embodiment of the present invention, as shown in FIG. 4, the dot spacers 12 are arranged on a concentric regular polygon (square in the figure) with the center of the resistance film 41 as an axis. The intervals are formed so as to be dense near the center and become gradually sparser from the center to the periphery.

By arranging the dot spacers only in the central portion of the insulating film where the input resistance is small, a gap can be formed between the resistive films. The resulting discontinuity of the output voltage and the like are reduced.

According to the third embodiment of the present invention based on the above concept, as shown in FIG. 5, the dot spacers 12 are arranged near the center of the resistive film 41, and a plurality of dot spacers 12 are arranged at equal intervals. Thus, a plurality of equilateral triangular input areas are formed only near the center.

In the fourth embodiment of the present invention based on the same concept, the dot spacers 12 are arranged near the center of the resistive film 41 as shown in FIG. Thus, a plurality of square input areas are formed only near the center.

In each of the above embodiments, there is a dot spacer made of an insulator between the resistive films, and it is not possible to eliminate the non-input area. However, the dot spacer is formed of a conductive material which does not impair the function of the resistive film. As a result, it is possible to eliminate the non-inputtable area.

In the fifth embodiment of the present invention, the dot spacer is made of a pressure-sensitive resin having, for example, flexibility and a pressure-sensitive characteristic shown in FIG. 7 (a). When the value is extremely high, the resistance value is greatly reduced, and the resistance films are electrically connected.

By forming the dot spacers from such a flexible pressure-sensitive resin, even when the interval between the dot spacers is small, the compressed dot spacers themselves act as conductors, causing discontinuities in the output voltage. It is possible to eliminate a non-input area.

In the above embodiment, as shown in FIG. 7 (b), holes 52 are formed at positions where the resistive film 51 faces the dot spacers 12, respectively, and pressed and crushed as shown in FIG. 7 (c). By bringing the dot spacer 12 into contact with the resistance film 51, a clear position can be detected.

The sixth embodiment of the present invention has dot spacers 12 made of a conductive material and each having a resistance value greater than the surface resistance of the resistive film 41. The resistive film 51 and each dot spacer 12 are shown in FIG. The connection is made via a very large contact resistance as shown by the broken line in a).

When the area partitioned by the dot spacers 12 is pressed as shown in FIG.
Are in direct contact with the resistive film 51 and are directly connected, and a plurality of dot spacers 12 are connected in parallel, so that a clear position can be detected as distinguished from other regions.

That is, a non-input area where the pressed position cannot be detected is minimized, and a coordinate input apparatus that operates stably even when the apparatus is downsized can be realized.

[0044]

As described above, according to the present invention, a non-input area where the pressed position cannot be detected is minimized, and a coordinate input device that operates stably even when the apparatus is downsized can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a coordinate input device according to the present invention.

FIG. 2 is a diagram showing experimental data by the inventors.

FIG. 3 is a diagram illustrating the principle of arrangement of dot spacers.

FIG. 4 is a diagram showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a third embodiment of the present invention.

FIG. 6 is a diagram showing a fourth embodiment of the present invention.

FIG. 7 is a diagram showing a first means for eliminating an input impossible area.

FIG. 8 is a diagram showing a second means for eliminating an input impossible area.

FIG. 9 is a perspective view showing a conventional coordinate input device.

[Explanation of symbols]

 3 Spacer 4, 5 Insulating film 12 Dot spacer 41, 51 Resistive film 52 hole

Claims (9)

[Claims] 1. An insulating film comprising a resistive film attached to one side thereof, each of which is opposed to the resistive film with the resistive film inside, and a resistive film formed on the resistive film of one of the insulating films. A plurality of dot spacers forming a gap in the insulating film, wherein the dot spacers are arranged densely at a central portion of the insulating film so as to be gradually sparser from the central portion toward the peripheral portion. Coordinate input device. 2. The coordinate input device according to claim 1, wherein the dot spacers are arranged on concentric circles around the center of the resistive film. 3. The coordinate input device according to claim 1, wherein the dot spacers are arranged on a concentric regular polygon having the center of the resistive film as an axis. 4. Two insulating films each having a resistive film adhered on one surface thereof and facing each other with the resistive film inside, and between the resistive films formed on the resistive film of one of the insulating films. A plurality of dot spacers that form a gap in the insulating film, the dot spacers are provided only at the center of the insulating film, and the intervals between the provided dot spacers are equal. Coordinate input device. 5. The coordinate input device according to claim 4, wherein a plurality of equilateral triangular input areas are formed at the center of the resistive film by the dot spacer. 6. The coordinate input device according to claim 4, wherein the dot spacer forms a plurality of square input areas in the center of the resistive film. 7. The method according to claim 1, wherein the dot spacer is formed of a pressure-sensitive conductive material.
The coordinate input device according to 3, 4, 5, or 6. 8. One of the resistive films has the dot spacer formed of a conductive material having flexibility, and the other of the resistive film has a hole formed at a position facing the dot spacer. Claims 1, 2, 3,
The coordinate input device according to 4, 5, or 6. 9. The dot spacer according to claim 1, wherein the dot spacer is formed of a conductive material, and a resistance value of the dot spacer is larger than a sheet resistance of a resistive film. Coordinate input device.