JPH0218726B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to the position of a writing instrument when writing information such as characters and figures on an input panel, or the position of an erasing instrument when erasing information written on an input panel. The present invention relates to an improvement of a drawing image input device called a so-called electronic blackboard, which can detect a position and input the position information.

[Technical background of the invention]

FIG. 4 shows the external appearance of the drawn image input device. This type of device has an appearance similar to a normal blackboard, and information such as letters and figures is written on the input panel 1 using a writing instrument 2 such as a commercially available water-based pen, just like a normal blackboard. The information written on the input panel 1 can be erased using the eraser 3. Then, the coordinate detection section detects the writing pressure of the writing instrument 2 when writing information on the input panel surface 1 or the pressing force of the erasing instrument 3 when erasing information, and detects the pressure of the writing instrument 2 or the erasing instrument 3 on the input panel surface 1. The configuration is such that coordinate value data can be input.

FIGS. 5 and 6 show a coordinate detection section and an equivalent circuit for explaining the principle of the coordinate detection section.

The main part of the coordinate detection section 4 is composed of two parallel substrates 5 and 6 arranged so that their respective electrode surfaces (resistance layer and conductive layer 16 to be described later) face each other.

The substrate 5 is made of a flexible substrate, and the input panel surface 1 described above is formed on the surface thereof. This input panel surface 1 is surface-treated so that information can be written with a writing instrument 2 and written information can be erased with an erasing instrument 3. Although not shown in the drawings, a resistance layer having a uniform sheet resistance is formed on almost the entire surface of the back surface of the substrate 5 by, for example, printing carbon ink so that the sheet resistance is uniform. ing. Also, around this resistance layer,
electrodes 7, 8, which are electrically connected to the resistance layer;
9 and 10 are provided. In these electrodes 7 to 10, current detection circuits 12 and 13 are provided for each of the two opposing pairs of electrodes 7 and 8 and 9 and 10, respectively.
is connected to the constant current source 15 by connecting the switching circuit 14 to the connection terminal a or b.

On the other hand, the substrate 6 is fixed to the device housing, and a conductive layer 16 is formed over the entire surface of the substrate 5 facing the resistance layer. Insulating projections 17 are uniformly distributed on the surface of this conductive layer 16. The protrusions 17 are formed, for example, by printing silicone ink on the surface of the conductive layer 16 at regular intervals and in the same shape.
Note that the constant current source 15 is connected to this conductive layer 16.

Next, regarding the principle of detection of the coordinate value data of the writing instrument 2 or erasing instrument 3 by the coordinate detection section 4, the sixth
This will be explained with reference to the figures.

When information is not written (or not erased) on the input panel surface 1, the resistance layer of the flexible substrate 5 and the conductive layer 16 of the substrate 6 are separated by the insulating protrusion 17, and both is in an insulated state. However, when information is written on the input panel surface 1, for example, the flexible substrate 5 is bent by the writing pressure of the writing instrument 2, and the resistive layer and the conductive layer 16 come into contact at the pressing point P (x, y) of the writing instrument 2. Both become electrically conductive. Therefore, the substrates 5 and 6
A constant current source 15 connected to the substrate 6 supplies a constant current I ₀ from the substrate 6 to the substrate 5 via the pressing point P (x, y).
flows, and the switching circuit 14 connects the connection terminal a.
, the current I ₀ is shunted through the resistive layer towards the opposing electrodes 7 , 8 . In this case, each electrode 7, 8 from the pressing point P (x, y)
Since the distance ratio up to and the resistance ratio of the resistive layer match, the current I ₀ is divided in accordance with this distance ratio. Therefore, if one of the shunted current values ix ₁ and ix ₂ , for example ix ₂ , is detected, data on the x-coordinate of point P can be obtained. Then, by switching the switching circuit 14 and detecting the current values ix ₂ and iy ₂ by the current detection circuits 12 and 13, coordinate value data corresponding to the two-dimensional coordinate values x and y of the pressing point P are obtained. can be detected.

The principle of detecting the coordinate value data of the writing instrument 2 when writing information (writing mode) has been explained above, but the detection of the coordinate value data of the erasing instrument 3 when erasing information (erasing mode) is performed in the same way. It will be done. However, in the erase mode, as in the writing mode, only coordinate value data representing two-dimensional coordinate values can be obtained, so it is impossible to determine whether the coordinate value data indicates the writing mode or the erasing mode. In addition, commonly used eraser 3
has a predetermined size so that the information can be easily erased, and even though the information written on the input panel 1 is erased in a predetermined area, the information obtained from the coordinate detection section 4 From the coordinate value data, the movement of the eraser 3 can only be understood as a simple movement of a point. Therefore, in order to transmit the information by displaying the information written or erased on the input panel 1 on an external display monitor, etc., it is necessary to obtain data that takes the above-mentioned problems into consideration. Therefore, in the conventional drawing image input device, a switch is provided around the input panel surface 1, and switching between writing mode and erasing mode is performed by turning the switch ON and OFF.
A sensor is provided in the storage section of the erasing tool 3, and this sensor detects whether or not the writing instrument 2 and the erasing tool 3 are stored in the storage section, thereby determining their usage status, that is, whether they are in writing mode or erasing mode. A method was used to determine whether the Also, if the erase mode is set by the above method,
The coordinate values (points) specified by the coordinate value data are converted into a predetermined erasing area that approximates the actual erasing area by the erasing tool 3 on the input panel surface 1 by the following method. In other words, by setting a predetermined erasure area based on coordinate values using a separately provided input control circuit, the image (information) on the monitor screen included in that area is erased. Ta.

[Problems with background technology]

However, the conventional drawn image input device described above has the following problems.

The method of switching between writing mode and erasing mode with a switch makes it easy to forget to operate it.
In addition, a method of automatically determining each mode by installing a sensor in the storage section of the writing instrument and erasing instrument is a method that automatically determines each mode. There is a possibility that the items will not be stored in the storage area. Therefore, in any case, the above methods are complicated to operate, and situations may occur where accurate information cannot be input, such as when the user intends to write but is in erase mode, or vice versa. The problem was that it was easy to use.

In addition, the method of setting the erasing area is to uniformly set a predetermined erasing area based on specified coordinate values in the input control circuit in advance, so depending on the size of the erasing tool, In some cases, the erase area on the monitor screen is smaller than the area of information actually erased on the input panel, or vice versa, and unless an eraser of a specified size is used, accurate erase area information cannot be obtained. I couldn't get it. Another possibility is to make the erasing area adjustable in stages and setting the erasing area according to the size of the erasing tool, but this operation would be very complicated, and the erasing tool is generally rectangular. Therefore, it is necessary to set an accurate erasing area, as is obvious when, for example, setting the erasing area according to the long side, but actually erasing mainly on the short side, or vice versa. That was difficult.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional drawbacks, and can automatically distinguish between writing mode and erasing mode without any operation by the operator, and can also correspond to the actual erasing area. An object of the present invention is to provide a drawn image input device that can automatically set an erasure area to be erased, and can therefore input and transmit much more accurate drawn image information than conventional devices. shall be.

[Summary of the invention]

Therefore, in the drawn image input device of the present invention,
In addition to the coordinate detection section that detects coordinate value data of the writing instrument or erasing instrument on the input panel surface, an area detection section is provided that detects area value data corresponding to the width of the pressing surface of the writing instrument or erasing instrument that presses the input panel surface. , an identification circuit determines whether the coordinate value data is in writing mode or erasing mode based on the area value data, and further, when the coordinate value data is in erasing mode, the area value data The above object is achieved by configuring the erase area setting circuit to set the size of the erase area based on the coordinate values specified by the coordinate value data.

[Embodiments of the invention]

Next, embodiments of the present invention will be described in detail using FIGS. 1 to 3. Note that the same components as those of the conventional example are given the same reference numerals, and the explanation thereof will be omitted.

Figure 1 shows how to determine whether the coordinate value data is in writing mode or erasing mode based on the given area value data, and when the coordinate value data is in erasing mode, it is determined based on the area value data. FIG. 2 is a block diagram illustrating a circuit configured to set an erasing area based on the data, FIG. 2 is an explanatory diagram of an area detection unit that detects area value data, and FIG. It is.

In these figures, 21 is an area detection section. The area detection unit 21 includes the coordinate detection unit 4 described above.
This is to detect the area of the input panel 1 that is pressed by the writing instrument 2 or the erasing instrument 3 when writing or erasing information on the input panel 1 . Therefore, it is disposed behind the input panel surface 1 at a position where it directly receives the pressing force on the input panel surface 1 from the writing instrument 2 or the like. Since it is basically disposed behind the coordinate detection section 4, a flexible substrate is used as the substrate 6 of the coordinate detection section 4 described above.

The area detection section 21, like the coordinate detection section 4, consists of two parallel substrates 23 and 24 arranged so that their respective electrode surfaces (conductive layers and conductive patterns 27 to be described later) face each other. It is configured.

The substrate 23 is made of a flexible substrate, the front surface 25 of which receives the pressing force of the writing instrument 2, etc., and the back surface (not shown) has a conductive layer formed over the entire surface. . still,
Since this substrate 23 is positioned so that its front surface 25 is in contact with the back surface of the substrate 6 (which is assumed to be a flexible substrate), the substrate 6 is also used instead of the substrate 23, and a conductive layer is formed on the back surface of the substrate 6. It is also possible to have a configuration in which If you configure it like this,
Not only can the number of parts be reduced, but the sensitivity of the area detection section 21 to pressing force can be improved.

On the other hand, the board 24 is fixed to the device housing,
A conductive pattern 27 and an insulating protrusion 28 are formed on the surface of the substrate 23 facing the conductive layer. As shown in FIG. 2, the conductive patterns 27 are arranged linearly over almost the entire surface of the substrate 24 at regular intervals. Further, the insulating projections 28 have a height exceeding the thickness of the conductive pattern 27, and are uniformly distributed on the surface of the substrate 24 on which the conductive pattern 27 is not formed. Incidentally, the protrusions 28 can be formed by printing silicone ink, similar to the protrusions 17 arranged on the substrate 6 described above.

The conductive patterns 27 are each independently connected to one end of an external resistor 30 having the same resistance value R, and the other end of the external resistor 30 is connected to a current detection circuit 31 as shown in FIG. Through the current power supply 3
Connected to 2. The current power source 32 is also connected to the conductive layer of the flexible substrate 23, and a closed circuit is formed by the contact between the conductive layer and the conductive pattern 27.

Next, the principle of detecting area value data in the area detecting section will be explained.

When information is not written (or not erased) on the input panel 1, the flexible board 2
Since the surface 25 of the substrate 3 is not subjected to pressing force, the surface 25 of the substrate 2
The conductive layer 3 and the conductive pattern 27 of the substrate 24 are as follows:
It is in an insulated state due to the insulating protrusion 28. However, when writing information on input panel 1 or erasing written information,
Since the input panel surface 1 (therefore, the surface 25 of the substrate 23) receives the pressing force of the writing instrument 2 or the erasing instrument 3, the flexible substrate 23 is bent, and the conductive layer and the conductive pattern 27 come into contact with each other, and the two become electrically conductive. What should be noted here is the pitch of the conductive pattern 27 provided on the substrate 24. In other words, since the pressing area of the writing instrument 2 such as a water-based pen and the erasing instrument 3 is very different, there is a difference in conductivity when pressing the input panel surface 1 with the writing instrument 2 and when pressing with the erasing instrument 3. The number of conductive patterns 27 that are in conduction with the layer will vary greatly. In principle, the smaller the pitch of the conductive patterns 27, the more faithfully the number of conductive patterns 27 that are in a conductive state changes in response to changes in the actual width of the pressing surface. Another thing to note is that when the conductive pattern 27 is arranged as shown in FIG. Even so, the number of conductive patterns 27 that become conductive changes accordingly. That is, the long side of the eraser 3 is the conductive pattern 2.
7 (the state shown in FIG. 2), the number of conductive patterns 27 that become conductive due to the pressure of the eraser 3 is greater than when the short side crosses the short side. .

In the case of the above-mentioned area detection unit 21, the conductive pattern 27 becomes conductive depending on the width of the pressing surface of the writing instrument 2 or erasing instrument 3 that actually presses the input panel surface 1, or the direction of the erasing instrument 3. This is a configuration in which the number of lines changes. As described above, if an external resistor 30 with the same resistance value R is added to each conductive pattern 27 and a constant voltage V ₀ is supplied to these, the current value detected by the current detection circuit 31 will be in the conductive state. It changes in proportion to the number of conductive patterns 27 (see FIG. 3). Therefore, by using the current value obtained by this current detection circuit 31 as area value data, information corresponding to the width of the pressing surface that presses the input panel surface 1 can be obtained.

In addition, when using the area detection section 21,
The board 24 is used as a fixed board, and the other boards 5, 6, 23
(or 5, 6) as a flexible substrate to have flexibility, and when writing (erasing) on the input panel surface 1 using the writing instrument 2 or erasing instrument 3, the pressing force is sufficiently transmitted to the substrate 24. There is a need. It has been confirmed that this can be achieved sufficiently by mainly selecting the material and thickness of each flexible substrate 5, 6, 23, and selecting the shape, size, pitch, and relative position of the insulating protrusions 17, 28. There is.

Next, the determination of the mode of the coordinate value data using the area value data and the setting of the erase area in the erase mode will be explained with reference to FIG.

As mentioned above, when writing (or erasing) information on the input panel 1, the writing instrument 2 or the erasing instrument 3
coordinate value data is detected by the coordinate detection section 4, and this coordinate value data is output to the input control circuit 34.
On the other hand, the area value data of the writing instrument 2 or erasing instrument 3 that presses the input panel surface 1 is output to the identification circuit 35 and the erasing area setting circuit 36. The identification circuit 35 is
The area value data is determined based on a preset boundary value, and a signal indicating whether the coordinate value data is in writing mode or erasing mode is output to the input control circuit 34. This determines the mode of the coordinate value data. Note that, as described above, since the writing instrument 2 such as a water-based pen and the erasing instrument 3 have clearly different pressing areas, the boundary value for determining the area value data can be easily set. On the other hand, when the identification circuit 35 determines that the area value data is an erase mode signal, it outputs the signal to the erase area setting circuit 36. The erase area setting circuit 36 receives this signal, sets an erase area based on the area value data, and outputs the erase area data to the input control circuit 34. As a result, when the coordinate value data is in the erase mode, the size of the erase area based on the coordinate values is determined by the area and direction of the eraser 3 that presses the input board surface 1. The erasing area can be set by, for example, erasing in several stages corresponding to the current value input to the erasing area setting circuit 36 (which changes in stages according to the number of conductive patterns 27 that are in a conductive state). Area data is set in advance, and these erase area data are output according to area value data (current value).

In this example, as shown in FIG.
By arranging the conductive patterns 27 at equal intervals in the horizontal direction (X direction), a current value corresponding to the length of the area pressing the input panel surface 1 in the X direction is obtained, and this is used as area value data. . However, the present invention is not limited to this. For example, the board 24 of the area detection unit 21 may be a flexible board, and a second area detection unit having the same configuration as the area detection unit 21 may be provided behind the board 24. It is also possible to obtain a current value corresponding to the length in the Y direction of the area that presses the input panel surface 1. If the current values in the X and Y directions are used as area value data, input panel surface 1
Since it is possible to obtain more accurate data corresponding to the area of the erasing tool 3 that is pressed, it is possible to set a more accurate erasing area corresponding to the actual erasing area.

〔Effect of the invention〕

As explained above, in the drawing image input device of the present invention, area value data corresponding to the width of the pressing surface of the writing instrument or erasing instrument that presses the input panel surface is detected, and based on this area value data, It is configured to automatically determine whether the coordinate value data representing the position of the writing instrument or erasing instrument on the input panel surface is in writing mode or erasing mode, and furthermore, in the case of erasing mode, the input panel surface is pressed. The configuration is such that an erasing area can be set corresponding to the actual pressing area of the erasing tool. There is no need to distinguish between writing instruments and erasing instruments, or to store writing instruments in designated storage areas. Information can be written (erase). Furthermore, it is possible to reliably distinguish between writing mode and erasing mode, and it is also possible to set an erasing area that corresponds to the actual erasing area, making it possible to input much more accurate image information than with conventional devices. , and can also be output to an external device.

[Brief explanation of drawings]

1 to 3 are diagrams for explaining an embodiment of the present invention, and FIG. 1 is a diagram for determining the type of mode of coordinate value data based on area value data, and in the case of erasing mode. FIG. 2 is a block diagram of a circuit configured to set an erasure area, FIG. 2 is an explanatory diagram of an area detection section for detecting area value data, and FIG. 3 is a diagram illustrating an equivalent circuit of the area detection section. FIG. 4 is an external view of a conventional drawn image input device, FIG. 5 is a diagram of a coordinate detection section that detects coordinate value data, and FIG. 6 is a diagram of an equivalent circuit of the coordinate detection section. It is. 1... Input board surface, 2... Writing instrument, 3... Erasing instrument, 4...
Coordinate detection section, 21... Area detection section, 35... Identification circuit, 36... Erase area setting circuit.

Claims (1)

[Claims] 1. The writing instrument or erasing instrument on the input panel surface due to the pressing force of the writing instrument when writing information such as characters and figures on the input panel surface, or the pressing force of the erasing instrument when erasing information written on the input panel surface. a coordinate detection section that detects coordinate value data; an area detection section that detects area value data corresponding to the width of the pressing surface of the writing instrument or erasing instrument that presses the input board surface; and an area detection section that detects the coordinate value data based on the area value data. an identification circuit that determines whether the value data is in writing mode or erasing mode; and when the coordinate value data is in erasing mode, the coordinate value specified by the coordinate value data is determined based on the area value data. What is claimed is: 1. A drawn image input device comprising: an erasing area setting circuit for setting a reference erasing area size.