JPH07175578A - Coordinate input device - Google Patents

Abstract

PURPOSE:To provide the coordinate input device which employs vibration pens, with a synchronous system one and an asynchronous system one mixed together, and can calculate respective indication positions of the two. CONSTITUTION:On the basis of the arrival time required for an elastic vibration wave, inputted from a vibration pen 3 (3') to a vibration transmission plate 8, to reach vibration sensors 6a-6d, an arithmetic control circuit 1 calculates a position indicated on the vibration plate 8 with the vibration pen 3 (3'). The vibration pen 3' generates vibration by its internal vibrator driving circuit 2' asynchronously with the arithmetic control part 1. The arithmetic control part 1 drives the vibration pen 3 synchronously through the vibrator driving circuit 2 unless the signal of the vibration pen 3' is detected to generate the vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device, for example, a coordinate input device having a plurality of vibrating pens.

[0002]

2. Description of the Related Art In a conventional coordinate input device using ultrasonic waves, the vibration generated by a vibrating pen is input to a vibration transmission plate which is an input surface, and the vibration is detected by a sensor arranged on the vibration transmission plate. Then, the position of the vibrating pen is calculated by the arithmetic control circuit based on the arrival time of the wave from the vibrating pen to the sensor. The counter of the arithmetic control circuit is activated at the same time as the vibrator drive circuit of the vibration pen, and counts the time until the vibration reaches the sensor. That is, the operation of the arithmetic control circuit and the operation of the vibrator drive circuit are synchronized.

There is also a method of asynchronously configuring the operation of the arithmetic control circuit and the oscillator drive circuit, and this method is useful for a wireless pen. Further, there is also a coordinate input device provided with a plurality of vibrating pens. In this case, each vibrating pen is driven at a different frequency using either a synchronous system or an asynchronous system, and a detection circuit is provided for each frequency. .

[0004]

However, the above-mentioned conventional example has the following problems. That is, in the conventional coordinate input device, the above-described synchronous method and asynchronous method cannot be mixed, and the configuration of the vibrating pen is limited. Further, since the vibrations of different frequencies are detected, there is a problem that the circuit scale of the detection circuit increases and the cost increases.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and has the following structure as one means for solving the above problems. That is, the position on the vibration transmission plate designated by the coordinate designating means is calculated based on the arrival time required for the elastic vibration wave inputted from the coordinate designating means to reach the vibration detecting means. A coordinate input device comprising: a calculating means for generating the vibration, wherein the coordinate instructing means generates a vibration in synchronism with the calculating means; and a second coordinate generating means for generating a vibration asynchronously with the calculating means. And a coordinate instructing unit,
It is characterized in that the first coordinate designating section and the second coordinate designating section are discriminated and the respective designated positions are calculated.

[0006]

With the above arrangement, the first coordinate designating section and the second coordinate designating section are provided.
It is possible to provide a coordinate input device that discriminates the coordinate pointing unit from each of the coordinate pointing units and calculates each pointing position, and it is possible to calculate each pointing position by mixing the vibrating pens of the synchronous method and the asynchronous method in a mixed manner. When the vibrating pen is provided, it is not necessary to detect vibrations of different frequencies, and the cost increase can be suppressed without increasing the scale of the detection circuit.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coordinate input device according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0008]

First Embodiment [Device Configuration] FIG. 1 is a block diagram showing a configuration example of a coordinate input device according to an embodiment of the present invention. In the figure, reference numeral 1 denotes an arithmetic control circuit, which controls the overall operation of this embodiment and calculates the coordinate position.

Reference numerals 2 and 2 ′ are vibrator driving circuits, which supply drive pulse signals to the vibrating pens 3 and 3 ′, which are the coordinate designating means, and the vibrator 4 (incorporated in the vibrating pen 3 (3 ′). 4 ') is driven to generate vibration.
The vibrating pen 3 is of a type that is connected to the main body of the apparatus by a wire, and the vibrating pen 3'is a wireless type. The generated vibration is input to the vibration transmission plate 8 via the pen tip 5 (5 ′). The vibration transmitting plate 8 is made of, for example, a transparent member such as acrylic or glass, and the coordinate input by the vibrating pen 3 (3 ′) is performed by touching the coordinate input effective area (hereinafter referred to as “effective area”) A on the vibration transmitting plate 8. It is done by doing.

A vibration isolator 7 is installed on the outer peripheral portion of the vibration transmitting plate 8 to attenuate the reflected wave reflected by the end surface of the vibration transmitting plate 8 so that the reflected wave returns to the central portion of the vibration transmitting plate 8. Prevent. 6a to 6d are vibration sensors, and the vibration transmission plate 8
A piezoelectric element or the like disposed near the four corners of the device, which converts mechanical vibration into an electric signal. A signal waveform detection circuit 9 inputs signals output from the vibration sensors 6a to 6d and amplified by an amplification circuit (not shown), and outputs the result of signal processing to the arithmetic control circuit 1. The arithmetic control circuit 1 calculates the coordinate position based on the signal input from the signal waveform detection circuit 9. The details of the arithmetic control circuit 1 and the signal waveform detection circuit 9 will be described later.

Reference numeral 11 is a display such as a liquid crystal display capable of displaying in dot units, and is arranged behind the vibration transmission plate 8. Reference numeral 10 denotes a display drive circuit, which displays a dot at a position on the display 11 corresponding to the position touched by the vibrating pen 3. The dots displayed on the display 11 can be seen through the vibration transmission plate 8. FIG. 2 is a diagram showing a detailed configuration example of the vibrating pens 3 and 3 '.
The vibrator drive circuit 2 uses the electric power supplied from the main body to
The low-level drive pulse signal supplied from the arithmetic control circuit 1 is amplified with a predetermined gain and supplied to the vibrator 4. Also,
The vibrator drive circuit 2'includes, for example, a battery and supplies a drive pulse signal of a predetermined level to the vibrator 4 '.

Here, the vibration frequency of the vibrator 4 (4 ') is selected so that a plate wave can be generated in the vibration transmission plate 8 made of glass or the like. Further, the vibrator 4 (4 ′) is driven by selecting a mode in which the vibration transmitting plate 8 vibrates in its thickness direction. In addition, this vibration frequency
If the resonance frequency includes (5 '), efficient conversion from electrical vibration to mechanical vibration becomes possible. Further, the elastic wave transmitted to the vibration transmitting plate 8 is a plate wave, and has an advantage that it is less likely to be affected by scratches or obstacles on the surface of the vibration transmitting plate 8 as compared with surface waves.

[Arithmetic and Control Circuit] The arithmetic and control circuit 1 executes a processing step described later at a predetermined cycle (for example, 5 ms) every
A drive pulse signal is output to the oscillator drive circuit 2 and the internal timer starts counting time. Vibrating pen 3
The vibration input from (3 ′) to the vibration transmission plate 8 reaches each of the vibration sensors 6a to 6d with a delay according to the distance from the input position. The signal waveform detection circuit 9 generates a signal indicating the vibration arrival timing of each of the vibration sensors 6a to 6d by the waveform detection processing described later.

The arithmetic control circuit 1 detects the vibration arrival time of each of the vibration sensors 6a to 6d based on each timing signal output from the signal waveform detection circuit 9, and the vibration pen 3
The touch position of (3 ′) is calculated, and the display drive circuit 10 is driven based on the calculated position information,
Display dots on the display 11. The vibration generated by the vibrating pen 3'is asynchronous with the arithmetic control circuit 1,
The coordinates are calculated by the arithmetic processing described later. The calculated position information is also output to an external device (not shown) by serial communication or parallel communication.

FIG. 3 is a block diagram showing a configuration example of the arithmetic control circuit 1. In the figure, 31 is a CPU such as a one-chip microcomputer, which is provided with an internal counter, a ROM for storing control procedures, a RAM used for arithmetic operations, and a non-volatile memory for storing constants and the like, and controls the entire embodiment. Take charge. Counters 32a, 32b, 33a and 33b respectively count a reference clock (not shown). Each of the counters starts timing with a drive pulse signal supplied from the CPU 31 to the vibrator drive circuit 2. This synchronizes the start of timing and the vibration detection by the vibration sensors 6a to 6d, and the time (delay time) until the vibration is detected can be measured.

Reference numeral 35 is an input port for the signal waveform detection circuit 9
Each vibration arrival timing signal is input from and is output to each counter 32a-33b. The counter 32a, which receives the signal from the vibration sensor 6a, displays the group delay time Tga.
The counter 32b that receives the signals from the vibration sensors 6b to 6d indicates the group delay times Tgb to Tgd, and the counter 33a that receives the signals from the vibration sensors 6a indicates the phase delay time Tpa.
The counter 33b, which receives the signals from the vibration sensors 6b to 6d, outputs the phase delay times Tpa to Tpd, respectively.

A determination circuit 36 determines whether or not four vibration arrival timing signals have been input to the input port 35. The CPU 31, which has received the signals indicating that the four vibration arrival timing signals have been input from the determination circuit 36, executes a predetermined calculation based on the delay times output from the counters 32a to 33d, and the vibrations on the vibration transmission plate 8 are transmitted. The coordinate positions of the pens 3 and 3'are calculated. Then, the calculated coordinate position information is output to the display drive circuit 10 via the I / O port 37 and also to an interface (not shown), so that the vibrating pen 3 can be output to the outside.
The coordinate position of (3 ') is output.

[Detection of Vibration Arrival Time and Calculation of Distance Difference] Next, the principle of measuring the vibration arrival time to the vibration sensors 6a to 6d will be described. FIG. 4 is a diagram for explaining a waveform input to the vibration waveform detection circuit 9 and a measurement process of the vibration arrival time due to the waveform. Although an example in which the distance difference between the vibration sensors 6a and 6b is detected for the vibration pen 3'is described below, the same applies to the vibration sensors 6c and 6d.

In the figure, a signal 41 indicates a signal supplied from the vibrator drive circuit 2'to the vibrator 4 '. This signal 4
1 is asynchronous with the arithmetic and control circuit 1 and drives the vibrator 4'to generate vibration. The generated vibration is transmitted to the vibration transmission plate 8, travels for a time tga according to the distance to the vibration sensor 6a, and then is detected by the vibration sensor 6a.

The signal 42 is a detection signal waveform output from the vibration sensor 6a, and since the vibration of this embodiment is a plate wave, the relationship between the envelope 421 and the phase 422 thereof is that during propagation through the vibration transmission plate 8. It changes according to the transmission distance. Here, the traveling speed of the envelope 421, that is, the group velocity is Vg, and the traveling speed of the phase 422, that is, the phase velocity is Vp.
And

First, focusing on the envelope 421,
The speed is Vg, and when a specific point on the waveform, for example, the zero cross point of the second-order differential waveform 423 of the envelope 421, that is, the inflection point of the envelope 421 is detected, the distance da between the vibration pen 3 ′ and the vibration sensor 6a is It is given by the following formula. da = Vg · tga (1) Distance between other vibration sensors 6b to 6d and vibrating pen 3'db to d
Similarly, d can be obtained, and the difference Δdb between the distance da and the distance db
Is given by the following equation by the difference 431 (Δtgb) in vibration transmission time.

Δdb = Vg · tgb−Vg · tga = Vg · Δtgb (2) Further, processing based on phase detection is performed in order to determine coordinates with higher accuracy. The time from a specific detection point of the phase 422, for example, the rising edge of the signal 41 to the zero cross point immediately after the level of the signal 42 first exceeds the threshold value 44, is tpa.
Then, the distance da between the vibration pen 3 ′ and the vibration sensor 6a is given by the following equation.

Da = na · λp + Vp · tpa (3) where λp: wavelength of elastic wave na: integer Note that the zero-cross point is the first of the signals 47 indicating that the signal 42 exceeds the threshold value 44. It is obtained by forming the window signal 48 of a predetermined period synchronized with the rising edge and detecting the first zero-cross point of the signal 42 in the period of the window signal 48.

Here, the distances db to dd between the other vibration sensors 6b to 6d and the vibration pen 3'can also be obtained in the same manner.
The difference Δdb between the distance da and the distance db is the difference 491 in vibration transmission time.
(Δtpb) is given by the following equation. Δdb = nb ・ λp + Vp ・ tpb- (na ・ λp + Vp ・ tpa) = (nb-na) ・ λp + Vp ・ (tpb-tpa) = nb '・ λp + Vp ・ Δtpb (4) However, nb, nb ': From the integer expressions (2) and (4), the integer nb' is represented by the following expression.

Nb ′ = int [(Vg · Δtgb-Vp · Δtpb) / λp + 1 / N] (5) However, N: real number other than zero (5) If N = 2, ± λ It is possible to determine nb 'if the variation is within 2 such as tg. Calculated from equation (5)
By substituting nb ′ into the equation (4), the distance difference Δdb can be accurately measured.

[Signal Waveform Detection Circuit] The above-mentioned time difference Δtg
The signals 431 and 491 for measuring Δtp and Δtp are generated by the signal waveform detection circuit 9. FIG. 5 is a block diagram showing a configuration example of the vibration waveform detection circuit 9. The figure shows the time difference Δtg from the outputs of the vibration sensors 6a and 6b.
Although a configuration example for detecting b and Δtpb is shown, the vibration waveform detection circuit 9 includes a similar configuration for the sensors 6a and 6c or 6a and 6d.

In the figure, the outputs of the vibration sensors 6a and 6b are amplified to a predetermined level by the preamplifier circuit 51, and then a band pass filter 511 removes an excessive frequency component. The signal output from the bandpass filter 511 (the signal 42 shown in FIG. 4) is input to the envelope detection circuit 52. The envelope detection circuit 52 is
For example, it is composed of an absolute value circuit and a low-pass filter, and the envelope of the input signal (4 shown in FIG.
21) is output to the envelope inflection point detection circuit 53.
The envelope inflection point detection circuit 53 detects the inflection point of the envelope and outputs the timing signal to the Δtg signal detection circuit 54. The tg signal detection circuit 54 is composed of a monostable multivibrator or the like, and has two vibration sensors 6 a, 6 input from the envelope inflection point detection circuit 53.
A signal (the signal 431 shown in FIG. 4) representing the time difference Δtgb is output from the processing result of the output signal of b. The signal 431 is input to the arithmetic control circuit 1.

On the other hand, the signal detection circuit 55 outputs the pulse signal (the signal 47 shown in FIG. 4) of the portion where the level of the input signal 42 exceeds the threshold value (44 shown in FIG. 4).
Monostable multivibrator 5 with this pulse signal input
6 outputs a gate signal (48 shown in FIG. 4) for a predetermined period from the rise of the signal. The tp signal detection circuit 57
In the period in which the gate signal 48 is active, the first zero-cross point of the signal 42 corresponding to the signal 48 is detected, and between the two detected zero-cross points, that is, the signal representing the time difference Δtpb (the signal shown in FIG. 4). 491) is output. The signal 491 is input to the arithmetic control circuit 1.

Since the vibration input from the vibrating pen 3 is a synchronous system, the arithmetic control circuit 1 can know the starting point of the vibration, and the tg signal detection circuits 54 and tp
The signal detection circuit 57 does not need to output the difference, but may output signals representing the times tg and tp, respectively. [Operation Procedure] Next, the operation of the present embodiment when the synchronous vibrating pen 3 and the asynchronous vibrating pen 3'are used simultaneously will be described. FIG. 6 is a flowchart showing an example of the operation procedure of this embodiment, which is executed by the arithmetic control circuit 1.
FIG. 7 is a timing chart showing an operation timing example of this embodiment.

In step S61 of FIG. 6, it is determined whether the vibrating pen 3 is in the input state. A writing pressure detection circuit (not shown) is incorporated in the vibrating pen 3 and outputs a signal indicating an input state (a signal 72 shown in FIG. 7). That is, when a writing pressure of a predetermined value or more is detected, it is regarded as an input state. Note that in FIG. 7, periods 2, 5, and 6 are in the input state. When it is determined that the vibrating pen 3 is in the input state, it is determined whether or not the signal of the vibrating pen 3 ′ is detected in step S62 without outputting the drive pulse signal, and the signal of the vibrating pen 3 ′ is detected. Then, when three pieces of difference data, which will be described later, necessary for calculating the coordinates of the vibrating pen 3 ′ are prepared, a drive pulse signal is output to the vibrating pen 3 in step S63 to calculate the coordinates, and in step S64, the vibrating pen 3 ′ is operated. The coordinates are calculated and the process returns to step S61. In addition,
A signal 71 shown in FIG. 7 is a signal indicating that the above-described three difference data are complete, and a drive pulse signal (a signal 73 shown in FIG. 7) is output by the signal.

If the signal of the vibrating pen 3'is not detected in step S62, the signal 71 falls and a predetermined time (time T shown in FIG. 7) elapses, and then step S62.
At 66, the drive pulse signal 73 is output to the vibration pen 3,
The coordinates are calculated and stored in the RAM or the like in the CPU 31. time
T is a time sufficient to determine that the vibrating pen 3'is not in the input state, and thereby prevents the vibrations generated from the two vibrating pens from overlapping. However, in consideration of the case where the superposition of vibration cannot be prevented by the time T, it is determined in step S67 whether the coordinates stored in the RAM are correct. As this determination method, for example, there is a method in which it is correct if the coordinates stored in the RAM are included in a predetermined range centered on the coordinates of the vibrating pen 3 calculated immediately before executing step S66. Note that the coordinates of the vibrating pen 3 calculated immediately before executing step S66 are also stored in the RAM or the like in the CPU 31.

If it is determined that the coordinates stored in the RAM are correct, the coordinates are output in step S68 and the process returns to step S61. If it is determined that they are not correct, the process returns to step S61 without doing anything. On the other hand, if the vibrating pen 3 is not in the input state in step S61, step S65
Then, it is determined whether or not the signal of the vibrating pen 3'is detected, and if detected, the process proceeds to step S64, and if not detected, the process returns to step S61.

In the above description, the case where the vibrating pen 3 is provided with the writing pressure detection circuit has been described, but the above procedure is possible even if the writing pressure detection circuit is not provided. For example, steps S61, 63, If 65 is deleted and the signal of the vibrating pen 3'is detected in step S62, step S64
Is executed, and if not executed, steps S66 to S6
8 should be executed.

[Calculation of Coordinate Position] FIG.
It is a figure explaining the principle which calculates the coordinate on the vibration transmission plate 8 of (3 '). In the figure, the positions of the vibration sensors 6a to 6d arranged near the four corners of the vibration transmission plate 8 are respectively indicated by Sa.
Sd to Sd, the linear distances da to dd from the position P of the vibrating pen 3 to the positions Sa to Sd of the respective vibration sensors can be obtained based on the principle described above. Then, the arithmetic and control circuit 1 calculates the coordinates (x, y) of the position P with the origin at the position Sa based on the straight line distances da to dd.

X = X / 2 + (da + db) (da-db) / 2X (6) y = Y / 2 + (dc + dd) (dc-dd) / 2Y (7) where X : Sa-Sd distance Y: Sa-Sb distance Next, the principle of calculating the coordinates of the vibration pen 3'on the vibration transmission plate 8 will be described. By detecting the vibration from the vibrating pen 3 ′, the distance difference Δdb to Δdd between the positions Sb to Sd with respect to the position Sa.
Can be obtained, and the coordinates (x, y) of the position P are calculated from the obtained distance difference as follows.

Each distance between the position P and the positions Sb to Sd is db = Δdb + da (8) dc = Δdc + da (9) dd = Δdd + da (10), and Δdd + Δdb- When Δdc ≠ 0, the area 1 shown in FIG.
And the condition of the region 3: At Δdb> 0 and Δdc> 0 and Δdb> Δdd and Δdb <0 and Δdc <0 and Δdb <Δdd, the coordinate P (x, y) is calculated by the following equation.

X = X / 2-Δdd ² / 2X + {Δdd ・ (Δdb ² + Δdd ² -Δdc ² )} / {X ・ (Δ
dd + Δdb-Δdc)} (11) y = Y / 2-Δdb / 2√ {4 x ² / (Y ² -Δdb ² ) +1} (12) However, x included in equation (12) is Value obtained by equation (11) Conditions for region 2 and region 4: Coordinate P (x, y) at Δdd> 0 and Δdc> 0 and Δdb <Δdd and Δdd <0 and Δdc <0 and Δdb> Δdd Calculated by

Y = Y / 2-Δdb ² / 2Y + {Δdb ・ (Δdb ² + Δdd ² -Δdc ² )} / {Y ・ (Δ
dd + Δdb-Δdc)} (13) x = X / 2-Δdd / 2√ {4y ² / (X ² -Δdd ² ) +1} (14) However, y included in equation (14) is The value calculated by Equation (13) .In addition, when Δdd + Δdb-Δdc = 0, that is, x = X / 2 Δdd = 0 (da = dd, db = dc) or y = Y / 2 Δdb When = 0 (da = db, dc = dd), the coordinate P (x, y) is calculated by the following formula.

Y = [Y ± √ {Δdb ² · (1 + X ² / (Y ² −Δdb ² ))}] / 2 (15) x = [X ± √ {Δdd ² · (1 + Y ² / (X ² -Δdd ² ))}] / 2 (16) As described above, the position of the vibrating pen 3 (3 ′) can be calculated in real time. As explained above,
According to the present embodiment, it is possible to mix the vibrating pens of the synchronous type and the asynchronous type and to calculate the respective designated positions.

[0040]

[Second Embodiment] A coordinate input device according to a second embodiment of the present invention will be described below. In the second embodiment, the first
About the same configuration as the embodiment, the same reference numerals are given,
Detailed description thereof will be omitted. FIG. 10 shows the second embodiment of the present invention.
It is a block diagram which shows the structural example of the coordinate input device of an Example.

In the above-described embodiment, the vibration is input by the vibration pen 3 and the wireless vibration pen 3'connected to the main body of the apparatus, but in this embodiment, the asynchronous wireless vibration pen 3'is used. The vibration is input by the wireless vibration pen 3'-1 of the synchronous system. Therefore, the circuit configuration related to signal waveform detection and the principle of calculating coordinates are the same as those in the above-described embodiments.

In FIG. 10, the sync signal sending circuit 1-1 attached to the arithmetic control circuit 1 sends a sync signal to the sync signal receiving circuit 2'-2 of the vibrating pen 3'-1 by light or electromagnetic waves. The arithmetic control circuit 1 starts the counter and, at the same time, instructs the synchronizing signal sending circuit 1-1 to send a signal. Sync signal receiving circuit 2'-2 that has received the sync signal
Outputs a drive pulse signal to the oscillator drive circuit 2'-1,
The oscillator drive circuit 2'-1 amplifies the drive pulse signal with a predetermined gain and supplies it to the oscillator 4'-1.

FIG. 11 is a flow chart showing an example of the operation procedure of the second embodiment, which is executed by the arithmetic control circuit 1. In the figure, it is determined in step S111 whether or not the signal of the vibrating pen 3'is detected. If detected, the coordinate of the vibrating pen 3'is calculated in step S112, and the process returns to step S111.

If the signal from the vibrating pen 3'is not detected, the vibrating pen 3'-1 is driven in step S113 to store its coordinates in, for example, the RAM in the CPU 31, and in step S114 in the RAM. It is determined whether the stored coordinates are correct. This is in consideration of the case where the vibrations generated by the two vibrating pens are superposed, and as the determination method, as described above, for example, the vibrating pen 3′-1 calculated immediately before executing step S113. There is a method of assuming that the coordinates stored in the RAM are included in a predetermined range with the coordinates of the center as the center. Note that the coordinates of the vibrating pen 3'-1 calculated immediately before executing step S113 are also CP
Store it in RAM etc. in U31.

When it is determined that the coordinates stored in the RAM are correct, the coordinates stored in the RAM are output in step S115 and the process returns to step S111. As explained above,
According to the present embodiment, in addition to the same effect as the first embodiment, since the two vibrating pens can be wireless, the operability of the vibrating pen can be improved.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0047]

As described above, according to the present invention, it is possible to provide a coordinate input device which discriminates between the first coordinate designating section and the second coordinate designating section and calculates respective designated positions. Since it is possible to mix different vibration pens and calculate the respective pointing positions, it is not necessary to detect vibrations of different frequencies when multiple vibration pens are provided, and the cost is increased without increasing the scale of the detection circuit. It has the effect of suppressing the rise.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a coordinate input device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a detailed configuration example of vibrating pens 3 and 3 ′ of FIG.

FIG. 3 is a block diagram showing a configuration example of an arithmetic control circuit in FIG.

4 is a waveform input to the vibration waveform detection circuit of FIG.
It is a figure for demonstrating the measurement process of the vibration arrival time by it.

5 is a block diagram showing a configuration example of the vibration waveform detection circuit of FIG.

FIG. 6 is a flowchart showing an example of an operation procedure of this embodiment.

FIG. 7 is a timing chart showing an operation timing example of the present embodiment.

FIG. 8 is a diagram illustrating the principle of calculating coordinates on the vibration transmission plate of the vibrating pen of the present embodiment.

FIG. 9 is a diagram illustrating conditions for calculating coordinates on the vibration transmission plate of the vibrating pen of the present embodiment.

FIG. 10 is a block diagram showing a configuration example of a coordinate input device according to a second embodiment of the present invention.

FIG. 11 is a flowchart showing an example of an operation procedure of the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 arithmetic control circuit 2, 2'vibrator drive circuit 3, 3'vibration pen 6a-6d vibration sensor 8 vibration transmission plate 9 signal waveform detection circuit 10 display drive circuit 11 display

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Katsuyuki Kobayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Masaki Tokioka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Yuichiro Yoshimura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (5)

[Claims] 1. Based on the arrival time required for the elastic vibration wave input from the coordinate designating means to the vibration transmitting plate to reach the vibration detecting means, the position on the vibration transmitting plate is designated by the coordinate designating means. A coordinate input device comprising a calculating means for calculating a position, wherein the coordinate instructing means generates a vibration in synchronization with the calculating means, and a first coordinate instructing section for generating vibration in asynchronism with the calculating means. And a second coordinate designating section, wherein the calculating means discriminates between the first coordinate designating section and the second coordinate designating section and calculates respective designated positions. apparatus. 2. The coordinate input device according to claim 1, wherein the calculation unit includes a drive unit that drives the first coordinate instruction unit. 3. The calculating means drives the first coordinate designating section via the driving section in accordance with information indicating the input state output from the first coordinate designating section. The coordinate input device according to claim 2. 4. The coordinate input device according to claim 3, wherein the information indicating the input state is generated according to the writing pressure applied to the first coordinate instruction unit. 5. The calculation unit drives the first coordinate designating unit via the driving unit when vibration from the second coordinate designating unit is not detected. The coordinate input device described.