JPH02125318A - Coordinate input device - Google Patents

Abstract

PURPOSE:To obviate replacement of a battery by supplying power through a charging terminal by a power supply means to charge a charging battery at the time of holding an input pen by a holding means. CONSTITUTION:The bottom of a pen stand 30 is provided with charging supply terminals 31 and 32 to be engaged with charging terminals 27 and 28 in the tail plug of the input pen, and charging terminals 27 and 28 and charging supply terminals 31 and 32 are electrically connected respectively when the tail plug part of the input pen 1 is inserted to the pen stand 30 in the direction of an arrow. At this time, a charging voltage is applied to charging supply terminals 31 and 32 from a device main body. Consequently, the input pen 1 is only inserted to the pen stand 30 to charge the input pen. Thus, replacewent of the charging battery of the input pen 1 is practically obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coordinate input device, and more particularly to a coordinate input device comprising a cordless coordinate input pen with a built-in rechargeable battery and a coordinate input panel.

[Prior Art] Conventionally, there is a method of inputting coordinates using ultrasonic vibration as a medium.

In a device employing this coordinate input method, the tablet (here, the vibration transmitting material) is made of glass, metal, etc., and a plurality of vibration sensors are arranged at predetermined positions on the corners of the tablet.

Then, by indicating a desired position on the tablet with an input pen having a vibrator, vibrations generated from the pen tip are propagated on the tablet. Each vibration sensor will detect this vibration, but the time until detection differs depending on the distance between the input vent and each vibration sensor. In other words, by measuring the vibration transmission time until it is detected by each vibration sensor, the distance from each vibration sensor to the point indicated by the input pen can be determined.
As a result, it becomes possible to determine the coordinate position of the point indicated by the input pen.

[Problems to be Solved by the Invention] Incidentally, in the case of a device that electrically operates an input pen and detects the touch position thereof, it is necessary to supply power to the input pen by some means.

Normally, the main body of the device and the input pen are connected by a dedicated cable, and the necessary power supply and various signals are sent and received via this cable.

However, with this, there is a problem in that it is impossible to avoid obstacles to improving operability, such as the cable getting wrapped around the hand.

Therefore, it is conceivable to input coordinates using a cordless input pen with a built-in battery, but if the battery is exhausted, for example, remove the cap and take out the internal battery.
You will have to go through the trouble of closing the cap again.

The present invention has been made in view of this problem, and an object thereof is to provide a coordinate input device that substantially eliminates the need to replace a rechargeable battery.

[Means for Solving the Problem] A coordinate input device of the present invention that solves this problem has the configuration shown below.

That is, it is a coordinate input device consisting of a cordless coordinate input pen with a built-in rechargeable battery and a coordinate input board, and a pair of cordless coordinate input pens for supplying charging power to the rechargeable batteries provided outside the coordinate input pen. a charging terminal; a holding means provided at a predetermined position outside the coordinate input area on the coordinate input panel and holding the input pen; and when the holding means holds the input pen, charging power is supplied to the charging terminal. and a power supply means for supplying.

[Function] In the configuration of the present invention, while the input pen is held by the holding means, the power supply means supplies power through the charging terminal to charge the rechargeable battery.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1. Explanation of the outline of the configuration (FIG. 1)> FIG. 1 shows a block configuration diagram of the coordinate input device in the embodiment.

In the figure, reference numeral 1 is a cordless input pen that indicates the coordinate position, and the details will be described later.
A start signal (light) related to the start of coordinate input is emitted via the window section 24 every period), and the pen tip is made to vibrate (includes a vibrator) in synchronization with the irradiation of the signal. Reference numeral 2 denotes a vibration transmission plate made of transparent glass (plastic may also be used), which propagates vibrations generated by the input pen 1, and forms a so-called coordinate input area. Vibration sensors made of piezo elements or the like shown as 3a to 3C are fixed to the three corners of the vibration transmission plate 2, and the vibrations generated from the input pen 1 are detected by these vibration sensors 3a to 3C. Reference numeral 4 denotes an anti-reflection material made of silicone rubber or the like for preventing vibrations transmitted from the human-powered bench 1 from being reflected at the periphery of the vibration transmission plate 2 and returning toward the center thereof. 5 is a display made of a CRT, LCD panel, etc., and is located behind the vibration transmission plate 2. In other words, since the vibration transmission plate 2 is located in front of the display 5, the displayed content can be read through the vibration transmission plate 8. A display drive circuit 6 controls the display drive of the display 5, and displays a predetermined image such as a dot or line based on instructions from an arithmetic control circuit 1o, which will be described later. Therefore, for example, by displaying images, characters, etc. input with the input pen 3 on the display 5 in their original size and in real time, it is possible to display the handwriting as if it were written on paper. It becomes possible. In addition, various other uses are possible, such as displaying a keyboard layout on the display 5 and giving instructions using the input pen 3.

7 is a signal waveform detection circuit, which detects signals corresponding to vibrations detected by the vibration sensors 3a to 3C, and outputs signals to the arithmetic control circuit 1.
A pulse signal corresponding to 1 is output.

Further, 8 is a start signal detection circuit, which converts an electric signal corresponding to the light emitted from the input pen 1 outputted from the light receiving section 9 into a predetermined pulse signal, and converts it into a predetermined pulse signal.
This is what is output to.

Explanation of the input pen (Figs. 2 and 3)> An example of the structure (cross-sectional view) of the input pen in the embodiment is shown in Fig. 2, and each component will be explained below.Basically, This input pen 1
contains all the components necessary for vibration generation.

The input pen 1 includes a vibrator 21 and a horn 20 (without a pen tip) that performs coordinate input and transmits vibrations to its tip, as well as the following configuration.

22 is a start signal generation circuit, and in the embodiment, the start signal generation circuit is
Several pulse signals are generated every cycle to light up the LED 23. The light from the LED 23 is emitted to the outside through the window 24 made of a transparent member, and is received by the light receiving section 9 on the device main body side. 25 is the oscillator 2 in synchronization with the signal generated from the start signal generation circuit 22.
This is a drive circuit that drives 1. This makes it possible to synchronize the emission of light and the vibration of the vibrator 21, that is, to detect the timing of the start of vibration by the input pen 1 on the device main body side.

26 is a rechargeable battery, the output terminal of which is supplied to the aforementioned start signal generation circuit 22, etc., and the charging terminal 27
．． 28 is provided at the tail plug of the input pen l. That is, instead of extracting the charging value built into the input pen 1 and loading another charged battery, the charging terminal 2 of the tail plug is used.
By applying a charging voltage to 7.28, the rechargeable battery 26 is attempted to be charged.

Specifically, a pen stand 30 as shown in FIG. 3 is provided on the main body of the device (anywhere other than the vibration transmission plate 2 is acceptable). Note that the illustrated case also shows a cross-sectional view.

At the bottom of the pen stand 30, charging supply terminals 31 and 32 are provided that engage with the charging terminals 27 and 28 of the tail plug of the input pen 1, and when the tail plug of the input pen 1 is inserted from the direction of the arrow shown in the figure. By inserting it into the pen stand 30, the charging terminal 27
．． 28 and charging supply terminals 31 and 32 are electrically connected, respectively. Here, it goes without saying that a charging voltage is applied to the charging supply terminals 31 and 32 from the main body of the device.

In this way, just by inserting the input vent 1 into the vent stand 30, charging will be done, and the input vent will actually be charged.
There is no need to replace the rechargeable battery.

Further, although the explanation is complicated, the vibration frequency of the vibrator 21 is selected to a value that can generate plate waves in the vibration transmission plate 2. Plate waves have the advantage that they are less affected by scratches on the surface of the vibration transmission plate 2, obstacles, etc. than plane waves or the like.

Further, when driving the vibrator, a vibration mode is selected in which the vibration ratio 21 mainly vibrates in the vertical direction in FIG. 2 with respect to the vibration transmission plate 2. Further, by setting the vibration frequency of the vibrator 21 to the resonance frequency of the vibrator 21, efficient vibration conversion is possible.

Description of Arithmetic Control Circuit (FIG. 4)> FIG. 4 shows the internal configuration of the arithmetic control circuit 11 in the embodiment, and each component and its operation outline will be described below.

In the figure, 41 is a microcomputer that controls the arithmetic control circuit 11 and the entire coordinate input device. 43 is a timer that measures a reference clock (not shown), and starts timing by receiving a signal from the start signal detection circuit 8 (a signal indicating that the light indicating the start of vibration of the input ben has been received). do.

In other words, this synchronizes the start of time measurement and the timing of vibration generation.

The circuits that constitute the lot number components will be explained in order.

Each vibration sensor 3a obtained via the signal waveform detection circuit 7
The detection signal of ~3C is sent via the detection signal input port 45,
It is input to latch circuits 44a to 44c. Latch circuit 4
4a to 44c correspond to vibration sensors 3a to 3c,
When each receives a detection signal from the corresponding vibration sensor via the input port 45, it latches the time value of the timer 43 at that time. When the determination circuit 46 determines that all detection signals have been received, it outputs a signal to that effect to the microcomputer 41.

When the microcomputer 41 receives this signal from the determination circuit 46, it reads the vibration arrival time from the latch circuits 44a to 44c to each vibration sensor, performs a predetermined calculation, and determines the coordinates on the vibration transmission plate 2 by the input bench 1. Calculate the position. Then, by outputting the calculated coordinate position information to the display drive circuit 6 via the I10 boat 47, a dot or the like is displayed at the corresponding position on the display, for example.

Explanation of vibration propagation time detection (Figures 5 and 6)
The principle of measuring the vibration arrival time to the vibration sensor will be explained.

FIG. 5 shows the detected waveform input to the signal waveform detection circuit 7,
FIG. 3 is a diagram for explaining a vibration transmission time measurement process based on this. Note that although the vibration sensor 3a will be explained below, the same applies to the other vibration sensors 3b and 3c.

The measurement of the vibration transmission time to the vibration sensor 3a is performed using the input bench 1.
It has already been explained that the process starts by receiving an optical signal from.

At this time, the illustrated vibration drive signal 51 is applied to the vibrator 21 from the drive circuit 25 in the input vent 1.

Vibration transmitting plate 2 from vibration ben 1 driven by this signal
The ultrasonic vibration transmitted to the vibration sensor 3a travels for a time t according to the distance to the vibration sensor 3a, and then reaches the vibration sensor 3a.
Detected in

A signal indicated by 52 in the figure indicates a signal waveform detected by the vibration sensor 3a.

By the way, the plate wave used in the embodiment is a dispersive wave, and therefore, the relationship between the envelope 521 and the phase 522 of the detected waveform with respect to the propagation distance within the vibration transmission plate 8 is Changes depending on distance.

Here, let Vg be the advancing speed of the envelope 521, that is, the group velocity, and Vp be the phase velocity of the phase 522. The distance between the input pen 3 and the vibration sensor 3a can be detected from the difference in group velocity Vg and phase velocity Vp.

First, focusing only on the envelope 521, its velocity is Vg, and when a point on a particular waveform, for example a peak, is detected as shown in the signal 53 in the figure, the distance between the input pen l and the vibration sensor 3a is d is the vibration transmission time tg, and d = V g - t g
-... ■This equation relates to one of the vibration sensors 3a, but the same equation applies to the other two vibration sensors 3b and 3.
The distance between c and the vibrating pen 3 is also expressed by the same principle.

Furthermore, in order to determine coordinate values with higher precision, processing based on phase signal detection is performed.

If the time from a specific detection point of the phase waveform signal 422, for example, vibration application to the zero crossing point after passing the peak, is tp, then the distance between the vibration sensor and the vibration pen is d=n ・λp''vp'tp...■ becomes.

Here, λp is the wavelength of the elastic wave, and n is an integer.

From the above equations ■ and 0, the above integer n is n = [(Vg-tg-Vp-tp)/λp+1/N]
It is expressed as −・・■.

Here, N is a real number other than O, and an appropriate value is used.

For example, if N=2, if it is within ±1/2 wavelength,
n can be determined. n calculated as above
By substituting 0 into equation 0, the distance between the input pen 1 and the vibration sensor 3a, and therefore the distance between the input pen 1 and the vibration sensor 3b,
3c can be accurately measured.

The signals 53 and 55 for measuring the two vibration transmission times tg and tp mentioned above are generated by the waveform detection circuit 9, which is configured as shown in FIG.

In FIG. 6, the output signal of the vibration sensor 3a is amplified to a predetermined level by a preamplifier circuit 61. In FIG. The amplified signal is input to the envelope detection circuit 62, and only the envelope of the detection signal is extracted. The timing of the peak of the extracted envelope is detected by the envelope peak detection circuit 63. The peak detection signal is formed into a signal Tg (signal 53), which is an envelope delay time detection signal of a predetermined waveform, by a Tg signal detection circuit 64 composed of a mono multivibrator or the like, and is input to the arithmetic control circuit 11.

Further, this signal Tg is applied to the monostable multivibrator 65.
The signal is supplied to a comparator Tp detection circuit 68 through a comparison level supply section 66 for comparison with the original signal delayed by the delay time adjustment circuit 57. The comparator Tp detection circuit 68 supplies the phase delay time signal Tp to the arithmetic control circuit 11.

Note that the circuit described above is for the vibration sensor 3a, and the same circuit is provided for the other vibration sensors 3b and 3c.

Therefore, if the number of sensors is generalized to h, then h detection signals of each of the envelope delay time Tgl-h and the phase delay time Tpl-h are input to the arithmetic control circuit 11.

Then, in the arithmetic control circuit 11, the above Tgl~h, 'r
The ptNh signal is input from the input port 45, and the time value (count value) of the timer 43 is taken into the latch circuits 44a to 44C as respective timing triggers. timer 43
is started in synchronization with the input pen drive, so
The latch circuits 44 to 44c include each vibration sensor 3a to 3C.
Data indicating the respective delay times of the envelope and phase of the signal will be latched.

Explanation of Coordinate Position Calculation (FIG. 7)> Next, the principle of actually detecting the coordinate position on the vibration transmission plate 2 using the input pen 1 will be explained.

Now, the coordinates of the vibration sensor 3a on the vibration transmission plate 2 are S, (0
, 0), that is, the origin, and the coordinate positions of the vibration sensors 3b and 3c are 5b (X, 0) and 5c (0, Y).

Then, let the coordinates of the input pen be P(x, y).

Then, based on the principle explained earlier, if the distances between the input pen 1 and each vibration sensor 3a to 3C are d and ~d, respectively, then P(x, y) to be obtained is calculated from the following formula from the Pythagorean theorem. It will be like this.

Here, "X" and "Y" are the horizontal and vertical distances of the vibration sensors 3b and 3c from the vibration sensor 3a.

As described above, the position coordinates of the vibrating pen 3 can be detected in real time.

Description of another embodiment (Fig. 8)> Input pen 1 and pen stand 30 in the above embodiment
It is not limited to.

For example, as shown in FIG. 8(a), charging terminals 81 and 82 are provided circumferentially on the side surface of the pen 81.

Charging supply terminals 84 and 85 are provided at predetermined positions within the pen stand 83 to apply charging voltages of respective polarities to the charging terminals 81 and 82 when the tail plug of the input pen 81 is inserted all the way.

In the above example, when charging the rechargeable battery of the input pen, it is necessary to first turn the pen tip and the plug part upside down. Therefore, we decided to change the structure of the input pen and pen stand into the 8th part.
It is also possible to do as shown in Figure (b).

Incidentally, 86 is an input pen, 87 and 88 are charging terminals of the input pen 86, 89 is a pen stand, and 90 and 91 are charging supply terminals.

As described above, according to the embodiment, the rechargeable battery inside the input pen is charged simply by inserting the input pen into the pen stand of the main body of the device. Therefore, there is no need to replace the rechargeable battery inside the pen.

In the embodiment, the coordinate input method is described in which the position of the input pen is detected by measuring the transmission time of vibration generated from the input pen, but other coordinate input methods may be used. No, the point is that the cordless input pen for inputting coordinates may be of any type as long as it requires an operating power source.

[Effects of the Invention] As explained above, according to the present invention, the input pen is charged simply by holding the input pen in the holding means of the main body of the device, thereby eliminating the need for troublesome battery replacement work. Naruyu

[Brief explanation of drawings]

Fig. 1 is a block diagram of the coordinate input device in the embodiment, Fig. 2 is a diagram showing the structure of the input pen in the embodiment, Fig. 3 is a cross-sectional diagram of the pen stand in the embodiment, and Fig. 4 is the embodiment. 5 is a timing chart for explaining the distance detection from the input pen to the vibration sensor, and FIG. 6 is a diagram showing a part of the configuration of the signal waveform detection circuit in the embodiment. Figure 7 is a diagram for explaining coordinate position calculation, Figure 8 (a
) and (b) are diagrams showing the structure of a pen stand and an input pen in another embodiment. In the figure, l...input pen, 1a...power supply section of the input pen, 2...vibration transmission plate, 3a-3c...vibration sensor,
4...Anti-reflective material, 5...Display, 6...
Display drive circuit, 7... Signal waveform detection circuit, 8
...Start signal detection circuit, 9...Light receiving section, 11.
...Arithmetic control circuit, 19...Charging socket, 20...
・Horn part, 21... Vibrator, 22... Start signal generation circuit, 23... -LED, 25... Drive circuit, 2
6... Rechargeable battery, 27 and 28... Charging terminal, 30.
...Pen stand, 31 and 32...° charging supply terminal, 41...Microcomputer, 43...Timer, 44a to 44c...Latch circuit, 45...Detection signal input board, 46...・Judgment circuit, 47...-I10
It's a boat. Patent Applicant: Canon Co., Ltd. (Tabi tβ Road) Figure 4 Figure 2 Figure 3 Figure 6 / Yo Figure ε 3 (b)

Claims (1)

[Scope of Claims] A coordinate input device consisting of a cordless coordinate input pen with a built-in rechargeable battery and a coordinate input board, wherein charging power is supplied to the rechargeable battery provided outside the coordinate input pen. a pair of charging terminals for charging the input pen; a holding means provided at a predetermined position outside the coordinate input area on the coordinate input panel for holding the input pen; and a pair of charging terminals for holding the input pen with the holding means; A coordinate input device comprising: power supply means for supplying charging power to a terminal.