JPH06337753A - Coordinate data input device - Google Patents

Abstract

PURPOSE:To provide the coordinate data input device which has a wireless type input pen and can input coordinate data. CONSTITUTION:This device includes a tablet 20 which has plural ultrasonic-wave transmitter receivers 26 at the periphery of a coordinate input surface and the wireless type input pen 10 equipped with an ultrasonic-wave transmitter receiver 12. The input pen 10 sends an initial ultrasonic pulse at the time of coordinate input operation, and sends a next ultrasonic wave pulse a specific time after the ultrasonic wave pulse is received. The tablet 20 sends an answering ultrasonic wave pulse a specific time after the ultrasonic wave pulse is received. Then the distance between the input pen 10 on the coordinate input surface and each ultrasonic wave receiver 26 is calculated from the time from the transmission of the answering ultrasonic wave pulse to the reception of the next ultrasonic wave pulse to calculate the coordinate input position (x, y) of the input pen 10 on the coordinate input surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate data input device, and more particularly to a coordinate data input device for inputting coordinate data of a designated position on a coordinate input surface.

[0002]

2. Description of the Related Art There are many demands for inputting figures and character information as coordinate data to a computer and outputting processing results as figures. As one of such coordinate data input devices, there is a flat-type tablet, and various types of principles are known.

FIG. 12 shows a conventional tablet type coordinate input device using ultrasonic waves. In this coordinate data input device, the pen tip coordinate data can be obtained according to the time required for the ultrasonic waves transmitted from the tip of the pen to reach the X and Y microphones provided on the coordinate input surface.

[0004]

However, in this conventional apparatus, since the wire for transmitting the ultrasonic waves is connected to the pen, the wire interferes with the operation of the pen, which is not convenient for the operator.

That is, in order to detect the time from the transmission of ultrasonic waves to the reception of ultrasonic waves, it is necessary to detect the ultrasonic transmission timing from the pen side. In order to detect this ultrasonic transmission timing on the measurement circuit side of the tablet,
There is a problem in that it is necessary to connect a wire to the pen, and this wire reduces the usability of the user.

The present invention has been made in view of the above conventional problems, and an object thereof is to have a wireless type coordinate input instruction means and to input coordinate data. To provide a device.

[0007]

In order to achieve the above object, the present invention comprises at least two first ultrasonic wave receivers on or around a coordinate input surface, wherein the first ultrasonic wave receivers are provided. Tablet means having at least one of the devices as a first ultrasonic transmitter / receiver, and a second ultrasonic transmitter / receiver, and wireless type coordinate input instruction means for performing coordinate input operation on a coordinate input surface of the tablet means. And the coordinate input instruction means transmits an ultrasonic pulse from the second ultrasonic transmitter / receiver during a coordinate input operation,
After a lapse of a predetermined time from the time when the second ultrasonic transmitter / receiver receives the ultrasonic pulse from the first ultrasonic transmitter / receiver,
A second drive controller for transmitting the next ultrasonic pulse from the second ultrasonic transmitter / receiver;
An ultrasonic pulse for response is transmitted from the first ultrasonic transmitter / receiver after a lapse of a predetermined time from a time point when one of the first ultrasonic receivers receives the ultrasonic pulse from the second ultrasonic transmitter / receiver. The first drive control unit for transmission and the first ultrasonic receiver have a reference time at any time from the time when the ultrasonic pulse is received to the time when the response ultrasonic pulse is transmitted. From the time from when each first ultrasonic receiver receives an ultrasonic pulse to calculate the distance between the coordinate input instruction means on the coordinate input surface and at least two first ultrasonic receivers. A distance calculation unit, and a position calculation unit that calculates a coordinate input position of the coordinate input instruction means on the coordinate input surface from the calculated distance and the distance between the at least two first ultrasonic receivers. And are included.

Here, it is preferable that at least three first ultrasonic receivers are provided at different positions on or around the coordinate input surface.

The tablet means can also be formed so that the coordinate input reference position on the coordinate input surface can be changed.

[0010]

[Function] Using a wireless type coordinate input instruction means,
When the coordinate input operation on the coordinate input surface of the tablet means is started, an initial ultrasonic pulse is first transmitted from the second ultrasonic transmitter / receiver provided in the coordinate input instruction means.

This initial ultrasonic wave pulse is received by each ultrasonic wave receiver provided on or around the coordinate input surface of the tablet means, and after a certain period of time, an ultrasonic wave pulse for response is transmitted from the ultrasonic wave transceiver. Sent to the coordinate input instruction means.

The coordinate input instruction means transmits the next ultrasonic pulse after a lapse of a certain time after receiving the ultrasonic pulse for response, and the ultrasonic pulse is received by each ultrasonic wave provided in the tablet means. Received by the vessel.

After a lapse of a fixed time after receiving the ultrasonic pulse, the tablet means similarly transmits the ultrasonic pulse for response to the coordinate input instructing means.

In this way, the ultrasonic pulse is repeatedly transmitted and received between the coordinate input instruction means and the tablet means.

At this time, the distance calculation unit provided in the tablet means sets a reference time to any time from the time when the ultrasonic pulse is received to the time when the response ultrasonic pulse is transmitted. The distance between the coordinate input instruction means and each ultrasonic receiver is calculated from the time until the ultrasonic receiver receives the ultrasonic pulse.

Then, the position calculator calculates the coordinate input position of the coordinate input instruction means on the coordinate input surface from the calculated distances and the distances between the ultrasonic receivers.

As described above, according to the coordinate data input device of the present invention, the input coordinates on the coordinate input surface designated by the coordinate input designating means are repeatedly measured in accordance with the ultrasonic pulse transmission / reception cycle. You can

In particular, according to the present invention, the tablet means sets the reference time for transmitting and receiving ultrasonic pulses, and calculates the distance between the coordinate input instruction means and the ultrasonic receiver on the tablet means side. With the configuration, it is not necessary to provide a connection line for setting the reference time on the coordinate input instruction means side, so that a wireless type coordinate data input device with good operability can be obtained.

Further, according to the present invention, by providing at least three of the first ultrasonic transmitters / receivers at different positions on the coordinate input surface or its periphery, the operator's hand holding the coordinate input instruction means can: Even when any one of the ultrasonic receivers cannot transmit and receive, the coordinate data can be continuously input using the remaining two ultrasonic receivers.

Further, in the present invention, the coordinate input instruction means is formed as a wireless type. Therefore,
By forming the tablet input device so that the coordinate input reference position on the coordinate input surface can be changed, good coordinate data can be input even when the tablet device is vertically or horizontally reversed, which is extremely convenient. .

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a preferred embodiment of a tablet-type coordinate data input device according to the present invention.

The coordinate data input device of the embodiment has an input pen 1 as a coordinate input instruction means to be gripped by an operator.
0 and a tablet 20 having a substantially rectangular coordinate input surface 24.

A case 2 is provided around the coordinate input surface 24.
2 are provided, and the four corners 21A, 21B of the coordinate input surface 24,
The first ultrasonic transceivers 26-1 and 26- are provided at 21C and 21D so as to transmit and receive ultrasonic waves toward the coordinate input surface 24.
Four of 2, 26-3 and 26-4 are provided.

FIG. 3 schematically shows a circuit diagram of the coordinate data input device of the embodiment.

The input pen 10 includes a second ultrasonic wave transmitter / receiver 12 and a second drive controller 10 for driving and controlling the same.
0 and are provided.

The second ultrasonic transmitter / receiver 12 is provided on the tip side of the input pen 10 and transmits / receives ultrasonic waves to / from each ultrasonic transmitter / receiver 26 provided at the corner of the coordinate input surface 24. Is configured to do.

The second drive controller 100 includes an input switch which is turned on at the time of coordinate input operation. When the input switch is turned on, the second ultrasonic transmitter / receiver 12 transmits an initial ultrasonic pulse. Let Further, while the input switch is turned on, each time an ultrasonic pulse is received, the next ultrasonic pulse is transmitted after a certain time has elapsed.

The input switch may be formed so as to be automatically turned on when the tip of the input pen 10 held by the operator comes into contact with the coordinate input surface 24 or when the tip is approached to some extent. It may be formed so as to be turned on / off by a person's operation. In a specific example described later, an input switch 102 of a type that is automatically turned on when the coordinate input surface 24 is touched is used.

Further, in the coordinate data input device of the embodiment,
A coordinate measuring circuit 200 is provided on the tablet 20 side.

The coordinate measuring circuit 200 transmits / receives ultrasonic waves to and from the first drive control section 40 for driving / controlling the ultrasonic wave transmission / reception of each ultrasonic wave transmitter / receiver 26-1, 26-2, ... 26-4. Based on the timing, the input pen 10 and each ultrasonic transmitter / receiver 26-1, 26-2, ... 2 on the coordinate input surface 24
6-4 includes a distance calculation unit 50 that calculates distances la, lb, ... Id, and a position calculation unit 60 that calculates the coordinate input position (x, y) of the input pen 10 from the calculated distance.

The first drive control section 40 is arranged so that after a predetermined time has elapsed from the time when any one of the ultrasonic transceivers 26-1, 26-2, ... The ultrasonic wave transmitter / receiver 26 is configured to transmit an ultrasonic pulse for response. The transmission of the ultrasonic pulse for response is performed by four ultrasonic transceivers 26-1, 26-2, ...
6-4 may be used, but in the embodiment,
In order to simplify the circuit configuration, any one of them, for example, only the ultrasonic transmitter / receiver 26-1 is used to transmit the ultrasonic pulse for response.

As described above, in this embodiment, the tablet 20 is used.
When the ultrasonic pulse is received on the side, the response ultrasonic pulse is transmitted to the input pen 10, and on the input pen 10 side, when the ultrasonic pulse is received, the next ultrasonic pulse is transmitted again. Has been done. Therefore, during the coordinate input operation, the ultrasonic pulse is repeatedly transmitted and received between the input pen 10 side and the tablet 20 side.

The distance calculation unit 50 includes the ultrasonic wave transmitter / receiver 2
Any one of 6-1, 26-2, ... 26-4 is the input pen 1
The reference time is any time from when the ultrasonic pulse is received from the 0 side to when the response ultrasonic pulse is transmitted. From this reference time, each ultrasonic transmitter / receiver 26-
26-4, from the time until the next ultrasonic pulse is received by each of the ultrasonic transducers 26-1, 26-2, ... 26-4 to the coordinate input position of the input pen 10. The distances la, lb, ... Id of are calculated.

In the embodiment, in order to simplify the calculation,
As shown in FIG. 2, two ultrasonic transceivers 2 capable of transmitting and receiving.
6-1 and 26-2 are selected, and the ultrasonic transceiver 26-
Distances la and lb between the coordinates 1 and 26-2 and the coordinate input position P of the input pen 10 are calculated and output to the position calculator 60.

The position calculation unit 60 detects the distances la and lb input in this way and the ultrasonic transmitter / receivers 26-1 and 26-2.
The coordinate (x, y) of the coordinate input position P on the coordinate input surface 24 is calculated from the distance L1 between 6-2 and output to a computer (not shown).

FIG. 4 shows a timing chart of the coordinate input operation of this embodiment. In addition, here, in order to simplify the description, the ultrasonic transceivers 26-1 and 26-2 are provided.
And the transmission / reception of ultrasonic waves between the ultrasonic transmitter / receiver 12 will be described, and the remaining ultrasonic transmitter / receivers 26-3, 26-
4 and the ultrasonic transmission / reception operation between the ultrasonic transmission / reception device 12 will be omitted.

First, when the operator grips the input pen 10 and starts the coordinate input operation on the coordinate input surface 24, the input switch 102 of the input pen 10 is turned on.

At the same time when the input switch 102 is turned on,
Initial pulse 51 from the ultrasonic transmitter / receiver 12 of the input pen 10
0-1 is transmitted, and this pulse 510-1 is transmitted to each ultrasonic transmitter / receiver 26-1 provided around the coordinate input surface 24,
26-2 detects the received pulses as 512A-1 and 512B-1.

In the apparatus of the embodiment, the ultrasonic transmitter / receiver 26-
When one receives ultrasonic pulses 512A-1, after a predetermined time t _d1 has elapsed, transmits an ultrasonic pulse 514-1 for response. The time of transmission of the ultrasonic pulse 514 becomes the reference time for distance measurement.

Then, the ultrasonic pulse 514-1 is
The ultrasonic transmitter / receiver 12 on the side of the input pen 10 outputs a pulse 516-
When it is received as 1, the next ultrasonic pulse 510-2 is transmitted from the ultrasonic transmitter / receiver 12 after a lapse of a fixed time t _d2 .

The ultrasonic pulse 510-2 is received as ultrasonic pulses 512A-2, 512B-2 by the ultrasonic transmitter / receivers 26-1, 26-2 on the tablet side.

Then, the measuring circuit 200 uses the transmission timing of the response ultrasonic pulse 514-1 as a reference time, and the next ultrasonic pulse 512A-2, 512B after the ultrasonic pulse 514-1 is transmitted. From the time t _A , t _B until the reception of -2, the ultrasonic input / output positions P of the input pen 10 and the ultrasonic transmitter / receivers 26-1, 26 provided at the corner portions 21A, 21B of the coordinate input surface 24. The distances la and lb from -2 are obtained as follows.

That is, the time from the transmission of the ultrasonic pulse 514 to the reception of the ultrasonic pulses 512A and 512B is t _A and t _B , and the ultrasonic pulse 514 is transmitted and then received by the input pen 10 side. the time until the t _a that, the time from the ultrasonic pulse 510 is transmitted until received by the ultrasonic transceiver 26-1, 26-2 of the tablet t _a, When t _b, these The relationship shown in the following equation is established between the two.

T _A = t _a + t _d2 + t _a = 2t _a + t _d2 t _B = t _a + t _d2 + t _b (1) Here, the t _d2 is a preset delay time on the input pen 10 side. Therefore, its value is already known. Therefore, from these equations, the distance la, ultrasonic propagation time t _a which corresponds to lb, t _b would be calculated using the following expression.

T _a = (t _A −t _d2 ) / 2 t _b = (t _B −t _d2 −t _a = t _B − (t _A + t _d2 ) / 2 (2) The position calculation unit 60 way to distance conversion time t _a, t _b determined distances la, seek lb. then, using techniques well known triangulation, these la, lb
And the value of the distance L ₁ between the ultrasonic transmitters / receivers 26-1 and 26-2, the coordinates (x, y) of the coordinate input position P are calculated and output to the computer.

According to the present embodiment, such a coordinate input operation is repeatedly performed for a second time, a third time, ... In a short time as shown in FIG. It can be performed almost continuously.

As described above, according to this embodiment, the two-dimensional coordinates of the designated position P can be continuously input using the wireless coordinate input pen 10, so that, for example, a graphic or various character data can be input. It can be done efficiently.

In particular, according to this embodiment, the input pen 10
Is formed as a wireless type, its operability is extremely good, and coordinate data can be input more efficiently.

In this embodiment, on the coordinate input surface 24,
Four ultrasonic transceivers 26-1, 26-2, ... 26-4
However, it is needless to say that at least two ultrasonic wave transmitters / receivers may be provided when the coordinate input position is calculated using the triangulation method. In this example,
Four ultrasonic transceivers are used because even if one or two of the four ultrasonic transceivers cannot transmit or receive ultrasonic waves for some reason during coordinate input operation, This is because the coordinate input operation can be continuously and stably performed using the remaining two ultrasonic transmitters / receivers.

Further, in the above embodiment, the four ultrasonic wave transmitters / receivers 26-1, 26-2, ...
Although four are provided, only one of these four may be formed as an ultrasonic transmitter / receiver and the rest may be formed only for ultrasonic reception, if necessary.

Further, in the above embodiment, the ultrasonic wave for response is transmitted from the ultrasonic wave transmitter / receiver 26-1 out of the four ultrasonic wave transmitters / receivers 26-1, 26-2, ... 26-4. However, if necessary, any one of the ultrasonic transmitters / receivers that have received the ultrasonic waves from the input pen 10 side is arbitrarily selected, and is formed so as to transmit an ultrasonic pulse for response. Good.

Further, as in the present embodiment, four ultrasonic transceivers 26-1, 26-2, ... 26 are arranged around the input surface 24.
In the tablet 20 provided with -4, any corner of the coordinate input surface 24 may be used as the reference surface. That is,
In the above-mentioned embodiment, as shown in FIG.
The case where the coordinate data is input with 1A as the reference position has been described as an example. However, as shown in FIG. 3, the reference position changeover switch 23 is provided and each corner portion 21A, 21B, 2
It may be formed so that any one of 1C and 21D is arbitrarily selected and set as a reference position. Thereby, even when the tablet 20 is used upside down and horizontally, it is possible to favorably input the coordinates, which is more convenient.

Further, in the present embodiment, as shown in FIG. 3, a temperature correction section 52 may be provided in the distance calculation section 50 to correct the error of the coordinate input position due to the temperature change. In this case, the time from when the response ultrasonic pulse 514 is transmitted from the ultrasonic transmitter / receiver 26-1 to when the ultrasonic pulse 514 is received by another ultrasonic transmitter / receiver 26-2 is set. The measurement may be performed, and this measurement time may be compared with the distance L ₁ between the ultrasonic wave transmitters / receivers 26-1 and 26-2 to correct the error in the ultrasonic wave propagation time. As a result, the distances la and lb between the coordinate input position P on the coordinate input surface 24 and the ultrasonic transmitter / receivers 26-1 and 26-2.
Of the coordinate input position data (x,
It is possible to accurately obtain y) without being affected by temperature changes.

Next, a specific example of the coordinate input device according to the present invention will be described in detail. In addition, in the embodiment, in order to simplify the description, the case where the ultrasonic transceivers 26-1 and 26-2 are provided at the corners of the coordinate input surface 24 will be described as an example.

First Specific Example FIGS. 5 and 6 show a circuit diagram of the coordinate data input device of this specific example together with a signal flow, and FIG. 7 shows a timing chart thereof. .

In the concrete example shown in FIGS. 5 and 6, FIG.
The first drive control unit 40 and the second drive control unit 100 shown in FIG.
2 and a part of the circuit configuration of the distance calculation unit 50 are illustrated, and the description of the specific circuit configuration of the position calculation unit 60 is omitted.

As shown in FIG. 5, when the switch 102 of the input pen 10 is turned on to start the coordinate input operation, the arrow 1
A signal flows along 000, and an ultrasonic pulse 510 is transmitted from the ultrasonic transceiver 12. Furthermore, the arrow 1010
A signal flows along the line, and after the ultrasonic transmission, the switch 114
Switches from the terminal a on the transmitting side to the terminal b on the receiving side.

That is, when the switch 102 is turned on,
The flip-flop 106 is set via the OR gate 104, and the oscillation pulse circuit 108 is driven. As a result, a pulse signal of 100 μsec is input from the transmission pulse circuit 108 to the ultrasonic transmitter / receiver 12 via the AND gate 110, the amplifier 112, and the switch 114, and the ultrasonic pulse 510 is transmitted. In addition, AND gate 1
The output of 10 flows along the arrow 1010, and the delay circuit 1
After being delayed by 100 μsec at 16 (after the end of transmission of the ultrasonic pulse), it is input to the changeover switch 114 via the OR gate 118, and the terminal is changed over from the a side to the b side.
Set to receive state. The delay circuit 116 is configured to function as a delay circuit by differentiating the trailing edge of the input pulse and inverting and outputting the differentiated signal. The same applies to the delay circuits 232 and 234 described later.

In this way, when the ultrasonic pulse 510-1 is transmitted from the input pen 10, the transmitted ultrasonic pulse 510-1 is transmitted to each ultrasonic transmitter / receiver 26 provided on the coordinate input surface 24. Pulse signal 512 at -1, 26-2
It is received as A-1, 512B-1.

When the ultrasonic transmitter / receiver 26-1 receives the ultrasonic pulse 512A-1, the ultrasonic pulse 5A is received.
The signal related to 12A-1 flows along the arrow 2000, and after a certain time t _d1 = 1.5 msec elapses, the ultrasonic transmitter / receiver 26-1 transmits the ultrasonic pulse 514 for response again.

That is, when the ultrasonic pulse 512A-1 is received, this signal flows along the arrow 2000 through the switch 201 and the amplifier 202-1 and resets the flip-flop 224-1 at the rising edge thereof, and The flip-flop 204 is set. At the same time, the output of the amplifier 202-1 is 100 μm along the arrow 2010 via the delay circuit 234 and the OR gate 236.
After being delayed by sec, the changeover switch 201 is input, and the switch 201 is switched from the input side terminal b side to the output side terminal a.
Switch to the side.

When the flip-flop 204 is set, its output signal is delayed by the delay circuit 2 as shown in FIG.
After a delay of t _d1 = 1.5 msec at 06, timer 2
08 is input. As a result, the timer 208 outputs a pulse, resets the counters 220-1 and 220-2, and drives the transmission pulse circuit 212.

As a result, the transmission pulse circuit 212 receives 10
A pulse signal of 0 μsec is transmitted via the AND gate 214, the amplifier 216, and the switch 201 to the ultrasonic transceiver 26-
1 and transmits the ultrasonic pulse 514-1 for response.

At this time, the output of the AND gate 214 is
According to the arrow 2030, the flip-flops 224-1 and 224-1
The outputs of the flip-flops 224-1 and 224-2, which are input to the set terminal of 24-2 and are set, are input to one terminals of AND gates 226-1 and 226-2. Thereby, AND gates 226-1 and 226-2
Becomes an ON state that accepts the output of the oscillator 222,
The clock pulse output from the oscillator 222 is input to the counters 220-1 and 220-2, and the counting operation is started.

That is, each of the counters 220-1 and 220
-2 is based on the time when the ultrasonic pulse 514 is transmitted,
The counting of the clock signal output from the oscillator 222 is started.

The output of the AND gate 214 is
It flows along the arrow 2060, is input to the changeover switch 201 via the delay circuit 232 of 100 μsec, and changes its terminal from the transmission side terminal a to the reception side terminal b.

In this way, when the ultrasonic pulse 514-1 is transmitted from the ultrasonic transmitter / receiver 26-1 on the tablet side, the ultrasonic pulse 514-1 is transmitted to the ultrasonic transmitter / receiver 12 on the input pen 10 side. Is received as a pulse signal 516-1.

The received pulse signal 516-1 and its related signals are shown in FIG.
3010, 3020, 3022, 3030, 3040, and the next ultrasonic pulse 510-2 is transmitted after a fixed time t _d2 = 1.0 msec.

That is, when the ultrasonic pulse 514-1 is received by the ultrasonic transmitter / receiver 12 as the pulse signal 516-1, this pulse signal is passed through the switch 114 and the amplifier 120 along the arrow 3000, and the flip-flop 13 is transmitted.
Input to 0 and set it. Flip flop 1
Since the set output of 30 is input to one terminal of the AND gate 132, the AND gate 132 is turned on.

Therefore, the clock signal output from the oscillator 138 is input to the counter 134 along the arrow 3010. Since the counter 134 has been reset at the time of the previous ultrasonic pulse transmission, the clock signal output from the oscillator 138 is counted from the beginning. 1
The msec decoder 136, based on this count value,
After the lapse of 1 msec corresponding to the delay time t _d2 , the pulse signal is output along the arrows 3022 and 3020.

That is, the output signal of the decoder 136 is input to the switch 114 along the arrow 3022, and the terminal is switched from the reception side terminal b to the transmission side terminal a. At the same time, the output signal of the decoder 136 flows along the arrow 3020, sets the flip-flop 106 via the AND gate 140 and the OR gate 104, and drives the oscillation pulse circuit 108. As a result, the transmission pulse circuit 108
Outputs a pulse signal of 100 μsec, and this output signal flows along the arrow 3030 and the ultrasonic transceiver 1
2, the next ultrasonic pulse 510-2 is transmitted from the ultrasonic transmitter / receiver 12.

At the same time, the output of the AND gate 110 flows along the arrow 3040, and the delay circuit 116 outputs 10
After a delay of 0 μsec, it is input to the changeover switch 114 via the OR gate 118, and its terminal is set to the transmitting side a.
To the receiving side b. In this way, the input pen 10 receives the ultrasonic pulse for a fixed time t _d2 =
After the lapse of 1.0 msec, the operation of transmitting the next ultrasonic pulse is performed.

In this way, when the next ultrasonic pulse 510-2 is transmitted from the input pen 10, this ultrasonic pulse 510-2 is transmitted by the ultrasonic transmitter / receiver 26 on the tablet side.
-1,26-2 with pulse signals 512A-2, 512B-
Received as 2.

These received pulse signals 512A-
2, 512B-2 flows along the arrow 2000 and resets the flip-flops 224-1 and 224-2.

Flip-flops 224-1 and 224-2
Is reset, the AND gates 226-1 and 226-2 of the output stage are turned off, and the counter 220
The counting operation of -1, 220-2 is stopped. Accordingly, the counters 220-1 and 220-2, as shown in FIG. 7, have a time t _A from the time of transmitting the ultrasonic pulse 514-1 to the time of receiving the ultrasonic pulse 512A-2, 512B-2.
The clock pulses corresponding to t _B will be counted. Then, each of these counters 220-1, 220-2
Count value of the decoder 230 along the arrow 2050.
-1, 230-2, and converted into time here, t
It is converted into a signal corresponding to _A and t _B and output.

In the embodiment, as shown in FIG. 7B, while the flip-flop 204 is set, the timer 208 outputs a pulse at a cycle of 2.5 msec. 220-2 is reset and outgoing pulse 212 is driven. Therefore, the measurement operation of t _A, t _B described above is performed for 2.5 msec.
Will be repeated in the cycle.

Then, the end of the coordinate data input operation is detected by the full count detector 240. That is,
A full count detector 240 is provided at the output stage of the decoder 230-1, and its detection output is the flip-flop 2
The signal is input to the reset terminal 04. This is because when the switch 102 of the input pen 10 is turned off and the coordinate input operation is stopped, the counter 220-1 continues counting operation and overflows. Therefore, this overflow is detected, and when the switch 102 is turned off, it is automatically detected. The flip-flop 204 is reset.

Second Specific Example FIGS. 8 and 9 show another specific example of the coordinate data input device of the present invention, and FIG. 10 shows its timing chart. The members corresponding to those in the first specific example are designated by the same reference numerals, and the description thereof will be omitted.

In the coordinate data input device of this specific example, the ultrasonic transmitters / receivers 26-1, 26 provided on the tablet side are arranged.
-2 is configured to alternately transmit and receive ultrasonic waves to and from the ultrasonic transmitter / receiver 12 of the input pen 10 and measure the distances la and lb.

First, as shown in FIG. 8, when the coordinate input operation on the coordinate input surface 24 is started using the input pen 10, the switch 102 is turned on and a signal flows as indicated by an arrow 1000. Then, the pulse signal output from the transmission pulse circuit 108 is input to the ultrasonic transmitter / receiver 12, and the ultrasonic pulse 510-1 is output.

The measuring circuit 200 on the tablet side includes the first drive control section 40-1 corresponding to the ultrasonic transmitter / receiver 26-1.
And a first drive controller 40-2 corresponding to the other ultrasonic transmitter / receiver 26-2, and both are formed to have substantially the same circuit configuration.

Then, for example, when the ultrasonic pulse 510-1 is transmitted from the input pen 10, the ultrasonic pulse is first received by one ultrasonic transmitter / receiver 26-1 and the received ultrasonic pulse 512A. -1 and its associated signal flow along arrow 2000 to reset flip-flop 224-1 and flip-flop 2
Set 04.

The set output of the flip-flop 204 is
As shown in FIG. 10B, 1.
It is delayed by 5 msec and input to the timer 208, which causes the timer 208 to output a pulse and the OR gate 21.
The transmission pulse circuit 212 is driven via 0. As a result, a pulse signal of 100 μsec is output from the transmission pulse circuit 212, and this signal is the AND gate 214-
1, the amplifier 216-1 and the switch 201-1 are input to the ultrasonic transmitter / receiver 26-1, and the ultrasonic pulse 514 for response is transmitted.

In the circuit of the embodiment, the timer 208
Outputs a pulse at a cycle of 1.5 msec, and the output thereof causes the first and second drive control circuits 40-1 and 40-2.
Is selectively driven and controlled. When the output Q _{1 of the} timer 208 is at the H level, the first drive control circuit 40-1 is drive-controlled as described above, and the other drive control circuit 40-
2 is in a masking state in which stop control is performed. On the contrary, when the output Q _{2 of the} timer 208 is H level,
The drive control circuit 40-2 operates and the other drive control circuit 4
0-1 is a masking state in which stop control is performed.

In order to perform such masking control, the transmission pulse circuit 212 and the amplifiers 216-1 and 216-2 are provided.
AND gates 214-1 and 214-2 are provided between and, and outputs Q ₁ and Q ₂ of the timer 208 are input to one of the input terminals of the AND gates 214-1 and 144-2, respectively. . Furthermore, the counters 220-1,
AND gates 228-1 and 228-2 are also provided between the 220-2 and the decoders 230-1 and 230-2, and the timer 208 is used as one of the input signals of these AND gates 228-1 and 228-2. The outputs Q ₁ and Q _{2 of} are respectively input.

Therefore, when the output Q _{1 of the} timer 208 is at H level, the AND gates 214-1, 228-1.
Is turned on, and the other AND gates 214-2, 228-
2 is off-controlled. On the contrary, when the output Q ₂ of the timer 208 is H level, the on / off state described above is reversed.

The basic structure of the measuring circuit of the embodiment other than this is the same as that of the first specific example, and the description thereof is omitted here.

In the measuring circuit 200 having the above-described structure,
On the tablet 20 side, the first ultrasonic transmitter / receiver 26
When -1 receives the ultrasonic pulse, ultrasonic wave 514 for response is transmitted from this ultrasonic transmitter / receiver 26-1 in the same manner as in the first specific example.

The ultrasonic pulse 5 thus transmitted
When the ultrasonic wave transmitter / receiver 12 of the input pen 10 receives 14, the received pulse signal 516-1 and its accompanying signal are indicated by arrows 3000 and 3022, 30 in FIG.
The ultrasonic wave flows along the arrow 40, and after the elapse of a certain time, the ultrasonic wave transmitter / receiver 12 transmits the next ultrasonic wave pulse 510.

That is, when the ultrasonic pulse 514-1 is received as the pulse signal 516-1 by using the ultrasonic transmitter / receiver 12, the received pulse signal 516-1 is transferred to the changeover switch 114, the amplifier 120, and the AND circuit. Gate 122, 1 msec delay circuit 124, OR gate 10
It is input to the flip-flop 106 via 4 and set. At the same time, the output of the amplifier 120 is input to the changeover switch 114 via the delay circuit 119 and the OR gate 118 along the arrow 322, and the contact is changed over from the input side terminal b to the output side terminal a.

The set output of the flip-flop 106 is input to the transmission pulse circuit 108 along the arrow 3000, and a pulse of 100 μsec from the transmission pulse 108 is transmitted / received through the AND gate 110, the amplifier 112, and the changeover switch 114. The pulse signal 510 is input to the device 12, and the next pulse signal 510 is transmitted. At this time, the output of the AND gate 110 flows to the changeover switch 114 along the arrow 340 via the delay circuit 116 and the OR gate 118, and the contact of the changeover switch 114 is changed over from the transmission side terminal a to the reception side terminal b.

In this way, when the next pulse signal 510 is transmitted from the ultrasonic transmitter / receiver 12 of the input pen 10,
This signal is received as a pulse signal 510-2 by the ultrasonic transmitter / receiver 216 on the tablet side, and this signal is indicated by the arrow 20.
00, the flip-flop 214-1 is reset, and the counting operation of the counter 220 is stopped.
At this time, since the output Q _{1 of the} timer 208 is at the H level, the AND gate 228-1 is in the ON state.
Therefore, the count output of the counter 220-1 is input to the decoder 230-1 via the AND gate 228-1,
The ultrasonic transceiver 26-1 outputs a signal corresponding to the ultrasonic transmission / reception time t _A from the time when the ultrasonic pulse 514-1 is transmitted to the time 512-2 when the next ultrasonic pulse 510-2 is received. It will be.

In this way, the first drive control circuit 40
When -1 is driven and the measurement of t _A is completed, the measurement circuit 200 of the embodiment then masks the drive control circuit 40-1 and drives the other drive control circuit 40-2. Similarly, ultrasonic waves are transmitted and received by the decoder 230.
Calculate and output t _B from -2.

That is, every time the timer 208 reverses its output at a cycle of 1.5 msec, the measurement operation of t _{A and} the measurement operation of t _B are repeated.

At this time, the ultrasonic transceivers 26-1 and 26-2
6-2 ultrasonic pulse transmission / reception times t _A and t _B, and ultrasonic pulse propagation times t between the ultrasonic transceivers 26-1 and 26-2 and the ultrasonic transceiver 12 on the input pen 10 side. _a ,
The relationship expressed by the following equation is established between t _b and t _b . However, t
_d2 is the delay time set by the delay circuit 124.

[0097] _{t A = 2t a + t d2} t B = 2r b + t d2 ... (3) Therefore, la shown in FIG. 2, the time t _a which corresponds to lb, t _b will be expressed by the following equation.

T _a = (t _A −t _d2 ) / 2 t _b = (t _B −t _d2 ) / 2 (4) Thus, according to the present specific example, the coordinates using the input pen 10 are used. The input operation can be performed in the same manner as the specific example.

Third Specific Example FIG. 11 shows a specific example of the temperature correction circuit section 52 shown in FIG.

In this temperature correction circuit section 52, when the temperature correction switch 260 is turned on, the AND gate 262 is turned on. When a temperature correction timing pulse is input in this state, the timing pulse 262 is input to the set terminal of the flip-flop 266, the flip-flop 266 is set in synchronization with the input of the pulse, and the set output is transmitted to the pulse circuit. It outputs to 212 and outputs to AND gate 250.

As a result, a pulse signal of 100 μsec is output from the transmission pulse circuit 212, which resets the flip-flop 266. At the same time, the transmitted pulse output is output to the ultrasonic transmitter / receiver 26-1 via the amplifier 216-1, and the ultrasonic pulse for temperature correction is output to the other ultrasonic transmitter / receiver 26-2.

At this time, the pulse signal output from the transmission pulse circuit 212 is input to the set terminal of the flip-flop 252 via the AND gate 250, and the set output of the flip-flop 252 causes the AND gate 254 to turn on. Become. Therefore, from the time when the ultrasonic pulse is transmitted, the counter 256 counts the clock pulse output from the oscillator 222.

When the ultrasonic pulse transmitted from the ultrasonic transmitter / receiver 26-1 is received by the other ultrasonic transmitter / receiver 26-2, the received pulse signal is amplified by the amplifier 202-.
It is input to the reset terminal of the flip-flop 252 via 2, and the AND gate 254 is turned off. This allows
The counter 256 stops the counting operation, but since the count value at this time is a value corresponding to the distance L1 between the ultrasonic transmitters / receivers 26-1 and 26-2, this is the decoder 2
58, the ultrasonic wave propagation time t corresponding to the count value
It is converted to 1 and output to the propagation time calculation unit 270. The propagation time calculation unit 270 includes both ultrasonic transceivers 26-
The distance L1 between 1 and 26-2 is divided by the propagation time t1 to calculate the propagation velocity of ultrasonic waves.

As a result, the distance calculator 50 shown in FIG.
Is measured ultrasound propagation time t _a, based on the t _b, x coordinate input position P, and y-coordinate temperature compensation, it can be obtained accurately.

Needless to say, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made within the scope of the gist of the present invention.

[0106]

As described above, according to the present invention,
Since the coordinate input instruction means for performing coordinate input on the coordinate input surface of the tablet means can be formed as a wireless type, there is an effect that a coordinate data input device which is convenient for the operator can be obtained.

Further, according to the invention of claim 2, even when one of the ultrasonic wave receivers on the tablet side becomes unable to transmit and receive due to the movement of the operator's hand during the coordinate input operation, the remaining The coordinate input position can be subsequently accurately determined by using the ultrasonic receiver.

Furthermore, according to the third aspect, the coordinate input reference position on the coordinate input surface can be changed, so that the coordinate input can be performed in any direction of the tablet means, and the coordinates are extremely convenient. A data input device can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a coordinate data input device according to an embodiment.

FIG. 2 is an explanatory diagram of a coordinate input operation performed using the device shown in FIG.

3 is a block diagram schematically showing a circuit configuration of the coordinate data input device shown in FIG.

FIG. 4 is a timing chart of the circuit shown in FIG.

FIG. 5 is a block diagram showing a specific circuit configuration of the coordinate data input device of the present invention together with a signal flow.

FIG. 6 is an explanatory diagram showing the block circuit diagram shown in FIG. 5 together with other signal flows.

FIG. 7 is a timing chart diagram of the block diagrams shown in FIGS. 5 and 6;

FIG. 8 is a block diagram explaining another specific example of the coordinate data input device of the present invention together with the flow of signals.

9 is an explanatory diagram showing the block diagram shown in FIG. 8 together with other signal flows.

10 is a timing chart diagram of the block diagrams shown in FIGS. 8 and 9. FIG.

FIG. 11 is a block diagram of a specific circuit configuration of a temperature correction unit used in the coordinate data input device of this embodiment.

FIG. 12 is an explanatory diagram of a conventional coordinate data input device.

[Explanation of symbols]

 10 Input Pen 20 Tablet 22 Case 24 Coordinate Input Surface 26 First Ultrasonic Transceiver 40 First Drive Control Section 50 Distance Calculation Section 52 Temperature Correction Circuit 60 Position Calculation Section 100 Second Drive Control Section

Claims (3)

[Claims] 1. A tablet comprising at least two first ultrasonic receivers on or around a coordinate input surface, wherein at least one of the first ultrasonic receivers serves as a first ultrasonic transceiver. Means and a second ultrasonic transmitter / receiver, and wireless type coordinate input instruction means for performing coordinate input operation with respect to the coordinate input surface of the tablet means, wherein the coordinate input instruction means, during the coordinate input operation, The ultrasonic pulse is transmitted from the second ultrasonic transmitter / receiver, and the second ultrasonic transmitter / receiver receives the ultrasonic pulse from the first ultrasonic transmitter / receiver, and after a predetermined time elapses, the first ultrasonic transmitter / receiver transmits the ultrasonic pulse. A second drive control unit for transmitting the next ultrasonic pulse from the second ultrasonic transmitter / receiver, wherein the tablet means includes one of the first ultrasonic receivers from the second ultrasonic transmitter / receiver. Super A first drive control unit for transmitting a response ultrasonic pulse from the first ultrasonic transmitter / receiver after a lapse of a predetermined time from the time of receiving the ultrasonic pulse; Is set as a reference time, and from the time from this reference time until each first ultrasonic receiver receives an ultrasonic pulse, At least two coordinate input instruction means on the coordinate input surface
A distance calculation unit that calculates a distance to each of the first ultrasonic receivers; and a distance on the coordinate input surface based on the calculated distance and a distance between the at least two first ultrasonic receivers. A coordinate data input device, comprising: a position calculation unit that calculates a coordinate input position of the coordinate input instruction means. 2. The first ultrasonic receiver according to claim 1, wherein at least three ultrasonic wave receivers are provided at different positions on or around the coordinate input surface.
A coordinate data input device characterized by being provided individually. 3. The coordinate data input device according to claim 1, wherein the tablet means is formed so that a coordinate input reference position on a coordinate input surface can be changed.