JPH06110598A - Coordinate detector - Google Patents

Abstract

PURPOSE:To provide the coordinate detector which can report the remaining capacity of a battery built in a stylus pen to a user without consuming the battery. CONSTITUTION:A proportional voltage generating circuit for generating a voltage in proportion to the remaining capacity of a built-in battery 201 and an electric field generating circuit for generating an electric field in proportion to the generated voltage from the tip of a pen are built in a stylus pen 20, The side of a tablet is provided with a comparator circuit 13 for comparing the peak value of a signal voltage after signal processing as induced by a scanning line 101 with a certain reference voltage and control circuit 14 for judging whether the generation of an alarm concerning the remaining capacity of the battery built in the stylus pen 20 is required or not based on the compared result and outputting this result.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate detecting device used in an information processing device or the like capable of handwriting input.

[0002]

2. Description of the Related Art Conventionally, an information processing apparatus such as a workstation or a personal computer has traditionally been provided with a display and a keyboard. As described above, in an information processing device having a keyboard as an input device, there is no particular problem when inputting code data such as characters and numbers, but when operating an application program or the information processing device itself, the operation contents are You have to enter the command name from the keyboard. Such a command input operation is an operation that is not necessary for a person who uses an information processing apparatus on a daily basis. However, it is difficult for general people who are not accustomed to using the information processing device to operate it, which is one of the reasons why the information processing device is shunned.

Under these circumstances, the use of input devices called pointing devices such as mice and trackballs has increased in recent years. In the information processing apparatus using this pointing device, an object representing the content or target of the process is displayed on the screen, and the cursor is moved to the object display position to perform the target process by instructing or selecting. be able to. Therefore, compared to an information processing device having only a keyboard, the operation is simpler and relatively easy for general people to accept.

However, in the case of a mouse or a trackball, a cursor moving operation is always required on the screen, and the operation also requires some kind of familiarity.

Therefore, recently, the development of an integrated handwriting input / display device in which a transparent tablet for coordinate detection is superposed on a display device such as a liquid crystal display has been actively developed. This integrated handwriting input / display device is excellent in operability because it can directly point an object displayed on the display device through a tablet with a dedicated input pen (hereinafter referred to as a stylus pen), and has excellent operability. When inputting, characters and figures are displayed as they are at the indicated position, so that you can input as if you were running a pen on the paper.

Tablets that constitute such an integrated handwriting input / display device are roughly classified into three types, that is, a resistance film type, an electromagnetic induction type, and an electrostatic induction type, depending on the coordinate detection method. In most tablets other than the resistive film type, the stylus pen is connected to the tablet controller by a cord.

However, when the stylus pen is connected by a cord, there is a problem that the cord interferes with the operation and makes it difficult to operate. For these reasons, a cordless coordinate detection device has been introduced to the world by incorporating a battery in the stylus pen. In this type of coordinate detection device, coordinate detection cannot be performed when the battery capacity is exhausted. Therefore, when an LED (light emitting diode) is attached to the stylus pen and the battery level becomes low, this L
The remaining amount warning is issued to the user by turning on the ED. However, this method has a problem that the life of the battery is further shortened because the battery with a low remaining amount is further consumed by driving the LED.

[0008]

SUMMARY OF THE INVENTION The present invention is intended to solve such a problem, and notifies the user of a warning regarding the remaining battery level without draining the battery built in the stylus pen. The object of the present invention is to provide a coordinate detection device capable of doing the above.

[0009]

In order to achieve the above-mentioned object, a coordinate detecting apparatus according to a first aspect of the present invention has a tablet having a plurality of scanning lines arranged in a grid and an arbitrary position on the tablet. In the coordinate detection device having a stylus pen for instructing, the stylus pen is a battery for supplying electric power to a circuit inside the stylus pen, and a switch for detecting whether or not the pen tip is pressed. Means, a proportional voltage generating means for generating a voltage proportional to the remaining amount of the battery when the pen tip is pressed, and an electric field having a magnitude proportional to the voltage generated by the proportional voltage generating means. A signal processing means for processing a signal induced in the scanning line by the approach of the stylus pen. A scanning line switching means for connecting one of the plurality of scanning lines to the signal processing means in order from the end, and a peak value of the signal voltage obtained by the signal processing means and a certain reference voltage. It is provided with a comparison means for making a comparison and a control means for judging whether or not a warning should be issued regarding the remaining amount of the battery built in the stylus pen based on the comparison result and outputting the fact.

In order to achieve the above-mentioned object, the coordinate detecting device of the second invention is provided with a tablet having a plurality of scanning lines arranged in a grid pattern, and for indicating an arbitrary position on the tablet. In a coordinate detection device having a stylus pen, the stylus pen is a battery for supplying electric power to a circuit inside the stylus pen,
Switch means for detecting whether or not the pen tip is pressed, proportional voltage generation means for generating a voltage proportional to the remaining amount of the battery when the pen tip is pressed, and proportional voltage generation means A built-in electric field generating means for generating an electric field of a magnitude proportional to the applied voltage from the pen tip, and the tablet is a signal for processing a signal induced on the scanning line when the stylus pen approaches. A processing means, a scanning line switching means for connecting one of the plurality of scanning lines to the signal processing means in order from the end, and a signal voltage obtained by the signal processing means is higher than a certain reference voltage. And a control means for determining whether or not a warning should be issued regarding the remaining amount of the battery built in the stylus pen based on the measurement result and outputting the information. To have.

[0011]

In the first aspect of the invention, when the stylus pen tip is pressed, a voltage proportional to the battery voltage is generated by the proportional voltage generating means. Then, the electric field generating means causes the pen tip to generate an electric field having a magnitude proportional to the generated voltage. As a result, a signal voltage corresponding to the remaining battery level is induced in the scanning line of the tablet. The induced signal is input to the comparison means through the signal processing means. The comparison means compares the peak value of the input signal voltage with a certain reference voltage and sends the result to the control means. The control means, from the comparison result,
For example, when it is known that the peak value of the signal voltage is equal to or lower than the reference voltage, it is determined that the battery remaining in the stylus pen has a small remaining amount, and this is output.

In the second aspect of the invention, when the stylus pen tip is pressed, a voltage proportional to the battery voltage is generated by the proportional voltage generating means. Then, the electric field generating means causes the pen tip to generate an electric field having a magnitude proportional to the generated voltage. As a result, a signal voltage corresponding to the remaining battery level is induced in the scanning line of the tablet. The induced signal is input to the measuring means through the signal processing means. The measuring means measures the time when the input signal voltage exceeds a certain reference voltage and sends the measurement result to the control means. Based on the measurement result, the control means determines whether or not a warning should be issued regarding the remaining amount of the battery built in the stylus pen, and outputs this.

Therefore, according to the above invention, the battery built in the stylus pen is not consumed,
A warning about the remaining battery level can be notified to the user.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining the configuration of a coordinate detecting device according to an embodiment of the present invention.

In the figure, reference numeral 10 is an input display screen, and specifically, it is constructed by stacking a transparent tablet on a display screen such as a liquid crystal display. This input display screen 1
In the tablet forming 0, a plurality of scanning lines 101 are arranged in a lattice pattern, that is, at equal intervals in the X / Y directions. Reference numeral 11 denotes a scanning line switching circuit composed of analog switches and the like, and one of the scanning lines in the X / Y direction is sequentially provided with a signal processing circuit 12 from the end.
Process to connect to. The signal processing circuit 12 amplifies the signal induced in the scanning line by the approach of the stylus pen 20 and performs a process of removing a high frequency component by filtering, that is, a low pass filter.
The ON / OFF state of the pen tip switch of 0 is determined, and further coordinate detection (or coordinate calculation) is performed. Reference numeral 13 compares the peak value of the signal voltage obtained by the signal processing circuit 12 with a certain reference voltage, and outputs the magnitude relation to the control circuit 14. The control circuit 14 controls the scanning line switching circuit 11, controls signals exchanged with the host, and the like, and needs to issue a warning regarding the remaining amount of the battery 201 built in the stylus pen 20 based on the comparison result of the comparison circuit 13. Determine the presence or absence.

FIG. 2 is a block diagram for explaining the structure of the stylus pen 20 described above. In the figure,
Reference numeral 21 denotes a pen tip portion of the stylus pen 20. The pen tip portion 21 has a structure in which it is slightly pressed in the pen body by being directly pressed against the display input screen 10 so that the pen tip switch 22 is turned on. . The pen tip switch 22 transmits the on / off state to the proportional voltage generating circuit 23 and the constant voltage generating circuit 24. The proportional voltage generation circuit 23 generates a voltage proportional to the remaining amount of the battery 201 (shown in FIG. 1) built in the stylus pen 20 when the pen tip switch 22 is in the ON state. Further, the constant voltage generation circuit 24 generates a constant voltage lower than the voltage generated by the proportional voltage generation circuit 23 when the pen tip switch 22 is off. Reference numeral 25 is an electric field generating circuit. The electric field generating circuit 25 causes the pen tip portion 21 to generate an electric field having a magnitude proportional to the voltage generated by the proportional voltage generating circuit 23 or the constant voltage generating circuit 24.

Next, the operation of the coordinate detecting device of this embodiment will be described. First, the control circuit 14 issues a coordinate measurement start command from the host.
To receive. Then, the control circuit 14 outputs a signal to the scanning line switching circuit 11 so that one of the scanning lines in the X / Y direction is sequentially connected to the signal processing circuit 12 from the end.

A signal voltage is induced on the scanning line as the stylus pen 20 approaches. At this time, the shorter the distance between the scanning line and the stylus pen 20, the larger the voltage induced. The signal processing circuit 12 amplifies the signal voltage induced on the scanning line to obtain a signal waveform as shown in FIG. 3, and then performs filtering to obtain a signal waveform as shown in FIG. Then, the signal processing circuit 12 measures the time from the start of scanning until the signal voltage reaches the peak (maximum value), and the coordinates are measured by converting this time into coordinate values.

Further, as shown in FIG. 5, the signal processing circuit 12 has a reference voltage (reference voltage 1) for switch ON / OFF determination, and the peak value of the signal voltage is 51 as shown by the signal waveform 51. If the reference voltage is exceeded, it is determined that the pen tip switch 22 of the stylus pen 20 is in the on state, and the above coordinate value is measured (or the coordinate value measurement result is validated). If the peak value is equal to or lower than the reference voltage as in the signal waveform 52, the pen tip switch 22 is determined to be in the off state and the coordinate value is not measured (or the coordinate value measurement result is invalid).

That is, when the pen tip switch 22 of the stylus pen 20 is on, the comparison voltage generating circuit 23
Is operated, and a voltage proportional to the remaining battery level is generated from the comparison voltage generation circuit 23. Then, the electric field generation circuit 25 generates an electric field having a magnitude proportional to the generated voltage from the pen tip portion 21, whereby a signal voltage whose peak value exceeds the reference voltage is induced in the scanning line, and the tablet side. The ON state of the pen tip switch 22 is determined.

When the pen tip switch 22 of the stylus pen 20 is in the off state, a voltage lower than the voltage generated by the comparison voltage generating circuit 23 is generated by the constant voltage generating circuit 24, so that the scanning line has the above-mentioned voltage. A signal voltage having a peach value equal to or lower than the reference voltage is induced, and the tablet side determines the off state of the pen tip switch 22.

Now, the stylus pen 20 on the tablet side
When it is determined that the pen tip switch 22 is on, the comparison circuit 13 is activated. Comparison circuit 1
As shown in FIG. 6, reference numeral 3 has a reference voltage (reference voltage 2) for battery residual quantity determination that is higher than the reference voltage (reference voltage 1) for switch on / off determination. The voltage is compared with the peak value of the signal voltage obtained by the signal processing circuit 12, and the comparison result is sent to the control circuit 14.

The proportional voltage generating circuit 23 is a stylus pen 2
Since a voltage proportional to the remaining battery level within 0 is generated, the remaining battery level is directly reflected in the peak value of the signal voltage induced in the scanning line. Therefore, based on the comparison result, the control circuit 14 determines that the remaining battery level is sufficient when the peak value is higher than the reference voltage, as in the signal waveform of 61, and does nothing. If the peak value is less than or equal to the reference voltage as in the signal waveform, it is determined that the remaining battery level is low, and a warning is sent to the host.

Thus, according to the coordinate detecting apparatus of the present embodiment, it is possible to notify the user of the warning regarding the remaining amount of the battery 201 without exhausting the battery 201 built in the stylus pen 20.

Next, another embodiment of the present invention will be described. Figure 7
FIG. 3 is a block diagram showing a configuration of a coordinate detection device of this embodiment. In the figure, the same parts as those in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted.

The coordinate detecting apparatus of this embodiment includes a measuring circuit 33 instead of the comparing circuit 13 of the above embodiment. Other configurations are the same as those in FIG. As shown in FIG. 8, the measuring circuit 13 includes a signal processing circuit 12
Of the input signal waveforms 81 and 82, the lengths of k and m in the figure,
That is, the time from when the signal voltage becomes equal to the reference voltage for switching on / off determination (reference voltage 1) to when it reaches the peak value is measured. If this time exceeds a certain value, it is determined that the remaining battery level is sufficient, and in other cases, it is determined that the remaining battery level is low, and a warning is notified to the host to that effect.

In this case, for example, as shown in FIG.
The lengths of x and y in the figure of the input signal waveforms 91 and 92, that is, the time when the signal voltage is equal to or higher than the reference voltage for switch on / off determination, is measured, and the battery remaining amount is measured for this time. You may make a decision.

[0028]

As described above, according to the coordinate detecting apparatus of the present invention, it is possible to notify the user of a warning regarding the remaining battery level without draining the battery built in the stylus pen. The battery life can be extended.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining a configuration of a coordinate detection device according to an embodiment of the present invention.

FIG. 2 is a block diagram for explaining the configuration of the stylus pen in FIG.

FIG. 3 is a diagram showing a waveform of a signal voltage induced in a scanning line after amplification.

FIG. 4 is a diagram showing a signal waveform after the filtering shown in FIG.

FIG. 5 is a diagram for explaining an on / off determination operation of a pen tip switch in the coordinate detection device of FIG.

FIG. 6 is a diagram for explaining the operation of the comparison circuit in FIG.

FIG. 7 is a block diagram for explaining the configuration of a coordinate detecting device according to another embodiment of the present invention.

FIG. 8 is a diagram for explaining the operation of the measuring circuit in FIG.

FIG. 9 is a diagram for explaining still another embodiment of the present invention.

[Explanation of symbols]

10 ... Input display screen, 101 ... Scan line, 11 ... Scan line switching circuit, 12 ... Signal processing circuit, 13 ... Comparison circuit, 1
4 ... Control circuit, 20 ... Stylus pen, 201 ... Battery, 21 ... Pen tip part, 22 ... Pen tip switch, 23 ... Proportional voltage generating circuit, 24 ... Constant voltage generating circuit, 25 ... Electric field generating circuit, 33 ... Measuring circuit .

Claims (2)

[Claims] 1. A coordinate detection device comprising a tablet having a plurality of scanning lines arranged in a grid pattern and a stylus pen for designating an arbitrary position on the tablet, wherein the stylus pen is the stylus. A battery for supplying electric power to a circuit inside the pen, a switch means for detecting whether or not the pen tip is pressed, and a voltage proportional to the remaining amount of the battery when the pen tip is pressed. The stylus pen is provided with built-in proportional voltage generating means for generating and electric field generating means for generating from the pen tip an electric field having a magnitude proportional to the voltage generated by the proportional voltage generating means. Signal processing means for processing a signal induced in the scanning line due to the approach of the scanning line, and one of the plurality of scanning lines in order from the end to the signal processing means. Continuing scanning line switching means, comparison means for comparing the peak value of the signal voltage obtained by the signal processing means with a certain reference voltage, and a warning about the remaining amount of the battery built in the stylus pen based on the comparison result. A coordinate detection device, comprising: a control unit that determines whether or not the occurrence is necessary and outputs the result. 2. A coordinate detection device comprising a tablet having a plurality of scanning lines arranged in a grid pattern and a stylus pen for indicating an arbitrary position on the tablet, wherein the stylus pen is the stylus. A battery for supplying electric power to a circuit inside the pen, a switch means for detecting whether or not the pen tip is pressed, and a voltage proportional to the remaining amount of the battery when the pen tip is pressed. The stylus pen is provided with built-in proportional voltage generating means for generating and electric field generating means for generating from the pen tip an electric field having a magnitude proportional to the voltage generated by the proportional voltage generating means. Signal processing means for processing a signal induced in the scanning line due to the approach of the scanning line, and one of the plurality of scanning lines in order from the end to the signal processing means. Continuing scan line switching means, measuring means for measuring the time when the signal voltage obtained by the signal processing means is above a certain reference voltage, and the remaining amount of the battery built in the stylus pen based on the measurement result. A coordinate detection device, comprising: a control unit that determines whether or not a warning is required and outputs the result.