JPS63120326A - Coordinate input device - Google Patents

Abstract

PURPOSE:To detect an input coordinate point with high stability and high accuracy by using a finger, a pencil, etc., to give deformations to 1st and 2nd vibration transmitting plates and detecting the vibrations supplied to the 1st vibration transmitting plate from a vibrator of the 2nd vibration transmitting plate via a contact point by a vibration sensor of the 1st vibration transmitting plate to decide the coordinates of the vibration input point. CONSTITUTION:The 1st and 2nd vibration transmitting plates 8a and 8b are set to a coordinate input device with a prescribed space secured between both plates. These plates 8a and 8b contain a vibration sensor 6 and a vibrator 4 respectively. Then the deformations are given to both plates 8a and 8b by means of a finger, a pencil, etc., instead of a special pen. The vibrations are detected by the sensor 6 of the plate 8a via the vibrator 4 of the plate 8b. This detection signal is processed by a signal waveform detecting circuit 9 and supplied to an arithmetic/control circuit 1. Then the vibrator 4 is controlled by the outputs of the circuit 1 and a vibrator drive circuit 2.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coordinate input device, in particular, detects vibrations input to a vibration transmission plate using a plurality of sensors provided on the vibration transmission plate, and detects vibrations on the vibration transmission plate. The present invention relates to a coordinate input device that detects the coordinates of a vibration input point on a vibration transmission plate from a delay time.

[Prior Art] Coordinate input devices using various input devices, tablets, etc. have been known as devices for inputting handwritten characters, figures, etc. to processing devices such as computers. In this type of system, input image information consisting of characters, figures, etc. is output to a display device such as a CRT display or a recording device such as a printer.

The following various methods are known for detecting the coordinates of a tablet in this type of device.

1) A method that detects changes in the resistance value of a sheet material placed opposite the resistive film.

2) A method that detects anti-magnetic or electrostatic induction using conductive sheets placed opposite each other.

3) A method that detects ultrasonic vibrations transmitted from the input pen to the tablet.

In the methods 1) and 2) described in -1-, it is difficult to form a transparent tablet because a resistive film or a conductive film is used.

In method 3), the table left can be constructed from a transparent material such as an acrylic plate or a glass plate.
By placing an input tablet on a liquid crystal display or the like (12), it is possible to construct an information input/output device with a good operating feel that can be used as if it were writing an image on paper.

[Problems to be Solved by the Invention] However, the above-mentioned ultrasonic vibration method has a problem in that it requires a special input pen called a vibrating pen. In other words, it is quite cumbersome to perform input operations by dragging a vibrating pen that has signal lines for synchronizing with the vibration detection side, signal lines for supplying power supply voltage, etc. There is a problem in that this method is inferior in operability compared to other methods that can be performed manually using an ordinary pen.

[Means for Solving the Problems] In order to solve the above-mentioned problems, in the present invention, vibrations input to the vibration transmission plate are detected by a plurality of sensors provided on the vibration transmission plate, and the vibrations are transmitted. In a coordinate input device that detects the coordinates of a vibration human force point on a vibration transmission plate J- from the vibration 'N delay time on the plate, first and second vibration transmission plates arranged a predetermined distance apart, and a first vibration A first vibration transmission plate based on a vibration detection signal output by a vibration sensor of the first vibration transmission plate, and a vibrator that applies vibration to a second vibration transmission plate, such as a plurality of vibration sensors provided on the transmission plate. means for detecting the coordinates of a vibration input point on the vibration input point, the transmission point of the vibration applied to the first vibration transmission plate when the first vibration transmission plate and the second vibration transmission plate are brought into contact; We adopted a configuration that detects the coordinates of

[Sakukawa] According to Kita's configuration, the first and second vibration transmitting plates are deformed using fingers, old-fashioned pens, pencils, etc., without using any special components such as vibrating pens. contact, the second
The coordinates of the vibration input point can be determined by detecting the vibration input from the vibrator of the vibration transmission plate to the first vibration transmission plate via the contact point with the vibration sensor of the first vibration transmission plate. can.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIGS. 1A and 1B show the structure of a coordinate input device employing the present invention. The device shown in FIG. 1 is designed to allow coordinate input by directly operating a tablet with a finger, pencil, etc., without using a special member such as a vibrating pen. FIG. 1(B) shows the tablet in an exploded state, and FIG. 1(A) shows the assembled state.

In FIGS. 1(A) and 1(B), the one indicated by reference numeral 8a←The convex part is a vibration sensor 6 that detects the vibration transmitted by a vibration transmission plate made of acrylic, glass plate, etc.
to communicate. The vibration transmitting plate 8a is provided with an anti-reflection material 11-7 made of silicone rubber or the like at its peripheral portion in order to prevent vibrations transmitted from the vibrating pen 3 from being reflected at the peripheral portion and returning toward the center. Supported.

The vibration sensor 6 provided at the corner of the vibration transmission plate 8a is composed of a mechanical to electrical conversion element such as a piezoelectric element. Output signals from each of the three vibration sensors 6 are input to a waveform detection circuit 9, and converted into detection signals that can be processed by a subsequent arithmetic control circuit 1.

On the other hand, in this embodiment, in addition to the vibrating pen 3, a vibration transmitting plate 8b is provided as a member for inputting vibrations to the vibration transmitting plate 8a. The vibration transmitting plate 8b is made of the same material as the vibration transmitting plate 8a and supported by an anti-reflection material 7, and two vibrators 4 made of a pressure plate or the like are provided at the negative corners of the vibration transmitting plate 8b. ing. This vibrator 4° is driven by a vibrator drive circuit 2.

The vibration frequency of the vibrator 4 is selected to a value that can generate plate waves in the vibration transmission JJQ8a, 8b of acrylic, glass, etc. When a plate wave is used for vibration transmission, an advantage can be obtained that it is less affected by scratches, obstacles, etc. on the surface of the vibration transmission plate 8a, compared to surface waves.

The vibration transmission plate 8b provided with the vibrator 4 is connected to the vibration sensor 6.
As shown in FIG. 2(B), the vibration transmitting plate 8a is disposed opposite to the vibration transmitting plate 8a with a spacer 8c interposed therebetween in a predetermined pressure path.

The vibration of the vibrator 4 is generated when the operator presses down the vibration transmission plate 8b on the upper surface side with a finger F as shown in FIG. 2(A) to deform it.
By contacting the lower vibration transmission plate 8a, the vibration is transmitted to the lower vibration transmission plate 8a. The vibration of the upper vibration transmission plate 8b is transmitted to the vibration transmission plate 8a via the contact point P of the vibration transmission plates 8a, 8b. Therefore, the above vibration sensor 6
By detecting the vibration using the sensor and measuring the duration of the vibration d, the coordinates of the contact point P can be detected by finger operation.

The above-mentioned vibrators 4 are not driven simultaneously, but are driven in a time-division manner, and coordinate calculation is performed based on the vibration transmission time obtained using each vibrator. The vibration transmission time is measured from the output, and the coordinate position of the input point P on the vibration transmission plate 8aJ- is detected.

The configuration and coordinate calculation processing of the calculation control circuit 1 will be described in detail below.

FIG. 3 shows the structure of the arithmetic and control circuit l shown in FIG. 1, that is, the structure of the vibration detection system using the drive system of the vibrator 4 of the vibration transmission plate 8b and the vibration sensor 6 of the vibration transmission plate 8a.

The microcomputer 11 includes an internal counter, ROM, and RAM. The drive signal generation circuit 12
It outputs a drive pulse of a predetermined frequency to the vibrator drive circuit 2 shown in the figure, and is activated by the microcomputer 11 in synchronization with the coordinate calculation circuit.

The count value of the counter 13 is latched into the latch circuit 14 by the microcomputer 11.

On the other hand, the waveform detection circuit 9 in FIG. 1 outputs timing information of a detection signal for measuring vibration transmission time for coordinate detection based on analysis of the signal waveform from the output of the vibration sensor 6 (described later). . This timing information is input boat 1
5 respectively.

The timing signal inputted from the waveform detection amount 289 is inputted to the input port 15 and compared with the count value in the latch circuit 14 by the determination circuit 16, and the result is transmitted to the microcomputer 11. That is, the vibration transmission time is expressed as a latch value of the output data of the counter 13, and coordinate calculation is performed using this vibration transmission time value.

FIG. 4 explains the detected waveform input to the waveform detection circuit 9 of FIG. 1 and the vibration transmission time measurement process based on the detected waveform. What is indicated by the reference numeral 41 in FIG. 4 is a single motion signal pulse applied to the vibrator 4 of the vibration transmission plate 8b.

The vibration transmitted from the vibration transmission plate 8b to the vibration transmission plate 8a travels within the vibration transmission plate 8a for a time tg corresponding to the distance to the vibration sensor 6, and then reaches the vibration sensor 6. The reference numeral 42 in FIG. 4 indicates the signal waveform detected by the vibration sensor 6. The plate wave used in this embodiment is a dispersive wave, so it is detected with respect to the propagation distance within the vibration transmission plate Ba. Waveform envelope 421 and phase 4
22 changes depending on the transmission distance during vibration transmission.

Here, the speed at which the envelope advances is the group velocity vg.

Let the phase velocity be Vp. The distance between the vibration input point P and the vibration sensor 6 can be detected from the difference in group velocity and phase velocity.

First, if we focus only on the envelope 421, its velocity is Vg, and when a certain point of a certain waveform -L, for example a peak, is detected as indicated by the reference numeral 43 in FIG. The distance #d is d = Vg - t g where the vibration transmission time is tg
...(1).

Although this equation relates to one of the vibration sensors 6, the distances between the other two vibration sensors 6 and the vibration input point P can be expressed using the same equation.

Furthermore, in order to determine more accurate coordinate values, each part performs processing based on detection of two-phase signals, from a specific detection point of the phase waveform 422 in FIG. 4, for example, from the vibration application to the zero cross point after passing the peak If the time tp is the distance between the vibration sensor and the vibration input point, then the distance d between the vibration sensor and the vibration input point is d=n*λp+Vp 11t p - (2)
becomes. Here, λP is the wavelength of the elastic wave, and n is an integer.

From the above equations (1) and (2), the above integer n is n=
[(Vg-t g-Vp-t p)/input p+ l/Nl
=-(3). Here, N is a real number other than O, and an appropriate value is used. For example, if N=2, n can be determined within ±17/2 wavelengths. n obtained as described above can be determined.

By substituting n determined as above into equation (2), the distance between the vibration input point P and the vibration sensor 6 can be accurately measured.

In the configuration shown in FIG. 1, two vibrators 4 are provided, so
-1, To measure the distance described above, first drive one of the vibrators 4 and calculate the distance information obtained by that vibrator (12), then drive the other vibrator and calculate the distance obtained by that vibrator. Compute information.

The two vibration transmission times t, ff and t shown in FIG.
The measurement of p is performed by the waveform detection circuit 9 shown in FIG.

The waveform detection circuit 9 is constructed as shown in FIG.

In FIG. 5, the output signal of the vibration sensor 6 is amplified to a predetermined level by a preamplifier circuit 51. The amplified signal is input to the envelope detection circuit 52, and only the envelope of the detection signal is extracted. The peak timing of the extracted envelope is detected by the envelope 1 co-beak detection circuit 53. The peak detection signal is detected by a signal detection circuit 5 composed of a mono multivibrator etc.
4, the envelope delay time detection signal T of a predetermined waveform is detected.
g is formed and input to the arithmetic control circuit 1.

Further, from this Tg signal and the original signal delayed by the delay time rA adjustment circuit 57, a phase 2 delay detection signal Tp is formed by a combination/event detection circuit 58 and inputted to the arithmetic control circuit 1.

The circuit shown above is for one vibration sensor 6, and circuits are provided for each of the other sensors as well.

If the number of sensors is generalized to 11, then h detection signals of the envelope delay time Tgl to h and the phase delay plane interval Tpi to h are inputted to the arithmetic control 1 channel 1, respectively.

In the arithmetic control circuit of FIG. 3, the above Tgl~h, Tpl-
The h signal is input from the human power port 15, and the count value of the counter 13 is taken into the latch circuit 14 at different timings.As mentioned above, the counter 13 is started in synchronization with the driving of the vibrator. Latch circuit 1
4, data indicating the respective delay times of the envelope and the phase is taken in.

As shown in FIG. 6, the positions where the vibration sensor 6 and the vibrator 4 are arranged at the corner of the vibration transmission plate 8a are designated by symbols SL to 83, and the linear distance between each person 231 to S3 and the input point P is ctl to
Let it be d3. At this time, the coordinates (x, y) of the position P of the vibrating force point P on the straight line distances d and -d3 are expressed by the following equation from the 3-square theorem.

Here, = X, Yl;j:S2. This is the distance along the X and Y axes between the vibration sensor 6 at the $3 position and the sensor at the origin (S1).

Here, the sum and difference of distance m d t to d-1 are, respectively,
A=d, +d2. B=d, -d, ,C=d.

10d3. Let us define D=dl-d.

On the other hand, as shown in FIG. 1, the vibrator 4 of the vibration transmission plate 8b
It is assumed that the vibration sensors are installed at the origin position sl and the position s2 in FIG. 6, and the vibration sensors are installed at the positions 21s2 and s3, respectively.

In this case, as is clear from FIG. 6, Sl, S2, S
Since the vibrations are transmitted through both the vibration transmission plates 8a and 8b, the distance information obtained by the vibration sensor G at each position of 3 is as follows.

First, when the vibrator at position S1 is vibrated, S2:
dl +d2 = A Also, since the vibrations of the two oscillators at position S1.52 are input at position S3, position i? For the transducer at lS1, S3: d1+d3=C Position: fLS For the transducer at 2, S3: d2+da=I Therefore, from the two acquired information C1 at position S3, each value of B=dl-d2, D=d, -d3 By substituting these into equations (4) and (5), the coordinates (x, y) of the vibration input point P can be determined in real time.

” Part 2, 1. The values of A and C are as in (2) and (3) above, respectively.
Since it is calculated from the formula, the group velocity Vg and phase velocity VP of the vibration transmission plates 8a and 8b must be strong.
In other words, since the characteristics of the vibration transmission plates 8a and 8b as a medium must be equal, the vibration transmission plates 8a and 8
b must be formed from the same material and have the same thickness.

Since there are no other restrictions, it is the vibration transmission plate 8a.

8b is made of a transparent plate such as glass or acrylic, and CR
It is conceivable to use it by overlaying it on a display device such as a T-display. In this case, a dot is displayed on the display corresponding to the coordinates of the detected vibration input point, and an image composed of elements such as points and lines input with a finger or the like is displayed as if it were a piece of paper. You can make it appear as if you have written to it.

Further, according to such a configuration, it is also possible to use an input method such as displaying a menu on the display and having the user select the menu item with a finger, or displaying a screen and touching a finger at a predetermined position.

Alternatively, if the vibration transmission plate does not need to be transparent, metal or the like may be used as the material.

Vibration sensor 6 or vibration transmission plates 8a and 8b of vibrator 4
The mounting position is not limited to the above and can be selected from various positions. However, the method of coordinate calculation is different.

FIG. 7 shows different arrangements of the vibration sensor 6 and the vibrator 4. In this embodiment, the vibrator 4 is provided at each position 51 to 53 of the vibration transmission plate 8b in FIG. Sensors were placed at locations S2, S3, and S4 in FIG.

In such a configuration, the coordinate calculation formula based on the straight line distance determined from the vibration delay time is as follows.

(Equation (4) above) or (Equation (5) above) or the X coordinate from either Equation (4) or (6), (5),
The y coordinate can be determined from either equation (7).

Only one of formulas (4), (6) or 5), or (7) may be used, but here, the average value of ,(5),(
7) Let the average value of y obtained by each equation be the detected y coordinate.

The data necessary for the above coordinate calculation uses all equations (4) to (7), so in addition to A-D consisting of the sum and difference of the distances d1, d2 and cii, ci3, E=d3+d4. F=d3-d4
．． G=d2+d4. While H=d2 d4 is required, the distance information obtained by each vibration sensor is as follows.

First, using the transducer at position S1, the sensors at positions S2 and S3 produce S2: d1+a2 = A S3: dl+d, 3=C Using the transducer at position S2, the sensors at positions S3 and S4 produce S3: d2+d- 3=X S4 :, d2+a4=G Using the vibrator at position S3, S4:d, +d4=E by the sensor at position 7154. From each of these combinations, the remaining glue, B, F, and H can be calculated. Therefore, the obtained 6 values are
) to (7) to obtain two types of x and y, and by averaging them, f+the final coordinates (x, y) of the input point P can be obtained.

According to the average value method using such different vibration transmission paths, it is possible to greatly improve the coordinate detection coefficient (1). For example, even if the vibration transmission path toward one vibration sensor is obstructed by an obstacle or the like, as long as the path toward the force vibration sensor is normal, detection will not become impossible or accuracy will not deteriorate.

In the description of one door, a configuration in which vibration sensors and vibrators are provided at two locations or three locations each is illustrated, but the number of sensors and vibrators may be further reduced.

For example, as shown in FIGS. 9 and 10, a configuration can be considered in which one vibrator is provided at position S1, and one vibrator is provided at each of positions S1 and S2.

In this case, the coordinate calculation formula becomes ノ=JOtsu2 ++ x-7 (9). on the other hand,
For the sensors at positions S1 and S2, the information of Sl:2dl $2: , d1 + d2 can be obtained, so the distance d from the sensor at the 1st position 2151 is
, and dl from the combination of the acquired information of the two sensors.
-d2 is obtained and substituted into the above equations (8) and (9) to obtain the coordinates (x, y) of the input point P. In this embodiment, the sensor and the vibrator need to be placed at both ends of one side of the vibration transmission plate.

If they are arranged diagonally, coordinate detection is impossible because it is impossible to determine from which side of the diagonal line between the sensor and the vibrator the vibration is transmitted.

According to such a system, it is possible to reduce the number of parts, simplify calculations, and improve processing speed.

As described above, various numbers and arrangements of vibrators and vibration sensors can be considered. In the above embodiment, the vibrator is provided on the -L side vibration transmission plate 8b, but a similar configuration is possible even if the vibrator is provided on the lower side and the sensor is provided on the upper vibration transmission plate.

In addition to the configurations shown in FIGS. 9 and 10, the upper vibration transmission plate 8b may be covered with another vibration transmission plate 8d as shown in FIG.

Furthermore, even if the vibrator and the vibration sensor are arranged separately on three or more vibration transmission plates arranged opposite to each other as shown in FIG. 12, the same coordinate input can be performed. Here, the ninth
In the arrangement of the sensors and vibrators shown in FIGS. 1 and 11, one of the sensors is provided on the uppermost vibration transmission plate 8d.

Even with this method, similar coordinate calculations can be performed based on equations (8) and (9).

[Effects of the Invention] As is clear from the above, according to the present invention, the vibration input to the vibration transmission plate is detected by a plurality of sensors provided on the vibration transmission plate, and the vibration input is detected from the vibration delay time on the vibration transmission plate. A coordinate input device for detecting the coordinates of a point on a vibration transmission plate J- includes first and second vibration transmission plates arranged a predetermined distance apart, and a plurality of vibration sensors provided on the first vibration transmission plate. and: The coordinates of the vibration input point on the first vibration transmission plate are determined based on the vibration detection signal output by the vibration sensor of the first vibration transmission plate and the vibrator that applies vibration to the vibration transmission plate of fS2. A detecting means is provided, and a configuration is adopted for detecting the coordinates of a transmission point of vibration applied to the first vibration transmission plate when the first vibration transmission plate and the second vibration transmission plate are brought into contact. Therefore, it is possible to provide an excellent coordinate manual input device that can input coordinates with one hand or with a pencil or the like without requiring any means such as a vibration input point.

[Brief explanation of the drawing]

Figures 1 (A) and (B) are explanatory diagrams showing the configuration of a coordinate input device adopting the present invention, Figure 2 (A) is an explanatory diagram showing a coordinate input operation, and Figure 2 (CB) is an explanatory diagram showing the configuration of a coordinate input device adopting the present invention. Figure 1 shows the arrangement of the vibration transmission plate, Figure 3 is a block diagram showing the structure of the arithmetic control circuit in Figure 1, and Figure 4 explains how to measure the distance between the vibration input point and the vibration sensor. Figure 55 is a block diagram showing the configuration of the waveform detection circuit in Figure 1, Figure 6 is an explanatory diagram showing the arrangement of the vibration sensor, Figures 7 and 8 are FIGS. 9 and 10 are explanatory diagrams showing the arrangement of vibration sensors and vibrators in different embodiments, respectively. FIGS. 9 and 10 are explanatory diagrams showing further different arrangements of vibration sensors and vibrators, respectively. FIGS. FIG. 5 is an explanatory diagram showing five different arrangements of vibration sensors and vibrators. l... Arithmetic control circuit 4... Vibrator 6... Vibration sensors 8a, 8b... Vibration transmission plate 15... Human powered boat 51... Front width amplifier 52... Envelope detection circuit 54. 58...Signal detection circuit 59...A/D conversion circuit [Input 11! ! I 乍σ)s<erqraFigure 2 (A) Figure 2 (8) (0 routes remaining) Ba Kunihiro poly ME bow? Each figure [L7] Figure 3: 10,90 of Ukeigamu Doguchi Road Figure 5 Figure 6

Claims (1)

[Claims] 1) The vibration input to the vibration transmission plate is detected by a plurality of sensors provided on the vibration transmission plate, and the coordinates of the vibration input point on the vibration transmission plate are determined from the vibration delay time on the vibration transmission plate. A coordinate input device for detection includes first and second vibration transmission plates arranged a predetermined distance apart, a plurality of vibration sensors provided on the first vibration transmission plate, and a second vibration transmission plate.
means for detecting the coordinates of a vibration input point on the first vibration transmission plate based on a vibration detection signal output by a vibration sensor of the first vibration transmission plate and a vibrator that applies vibration to the vibration transmission plate; A coordinate input device that is provided and configured to detect the coordinates of a transmission point of vibration applied to the first vibration transmission plate when the first vibration transmission plate and the second vibration transmission plate are brought into contact with each other. . 2) The coordinate input device according to claim 1, wherein the first and second vibration transmission plates have equal vibration transmission characteristics.