JP2579961Y2 - Position indicator - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointing device used for input to a computer, and more particularly to a writing device such as a stylus pen.

[0002]

2. Description of the Related Art Conventionally, various stylus pens have been devised according to differences in the principle of coordinate detection. For example, one using light called a light pen, one configured to pick up the indicated position by ultrasonic waves, one using magnetic coupling, one using magnetostriction, one using electrical resistance, one using electrostatic coupling The stylus pen required to indicate a point on the coordinate detection surface called a tablet according to various coordinate detection principles, such as those using a tablet, those using electromagnetic coupling, those using electromagnetic resonance, etc. Is done.

The above-mentioned stylus pen is generally connected to another device such as a tablet by a cable, and a switch signal (for a mouse, which corresponds to a click signal in the case of a mouse) for up / down or selection of the pen is transmitted to the stylus pen. It is configured to be transferred to the tablet side or the host computer side via a cable.

Some so-called cordless digitizers which do not connect a stylus pen and a coordinate detecting device with a cable, so-called cordless digitizers, are one of them. One of them is the same applicant as the present invention. Has proposed a "position detecting device" (Japanese Patent Publication No. 2-53805). The configuration will be briefly described.
A plurality of loop coils are juxtaposed in both Y directions, and a selection circuit, a switching circuit, and the like are provided. The loop coil functions as a radio wave transmitting unit or a radio wave receiving unit. A tuning circuit having a resonance frequency capable of resonating with the frequency of the radio wave emitted from the radio wave transmitting means is provided on the position indicator side, and the position indicator reflected and reflected the radio wave emitted from the coordinate detector. The radio wave is received by the coordinate detecting device. By processing the level of the voltage detected in each loop coil, the XY coordinate value of the position indicated by the position indicator is calculated.

[0005] The applicant of the present invention has filed an earlier application entitled "Position Pointer State Detection System" (Japanese Patent Publication No. 3-653).
No. 0), a method for detecting which one of a plurality of switches in a position indicator of a coordinate input device is being operated, wherein a radio wave is transmitted from a radio wave generator and provided on the position indicator by the radio wave. In response to the plurality of switches, the tuning circuits configured by the operation of the switches are excited, radio waves are received by radio wave receiving means, and the received radio waves are transmitted from the tuning circuit formed by any of the switches. A "method of detecting a switch operation state of a position indicator" in a coordinate input device for detecting whether a switch is operated based on the result of the detection is proposed. In "Position Indicator State Detection Method" (Japanese Patent Application Laid-Open No. 63-56716), a position indicator has been proposed in which the tuning frequency of the tuning circuit changes continuously around a predetermined frequency. Furthermore, "Position indicator status identification method" (Japanese Unexamined Patent Publication No.
No. 3,257,823), the loss inside the tuning circuit can be changed by making the Q value of the tuning circuit variable,
A position indicator was proposed to identify the switch state by detecting the attenuation of the reflected signal.

[0006]

The problem to be solved by the present invention is not limited to the cordless digitizer previously proposed by the applicant of the present invention. Eliminating the code for connecting between the position indicator and the coordinate detecting device is achieved by man-machine interface or Although desirable from an ergonomic standpoint, from that point of view, an important issue is how operable the switches used in the switch are.

Considering only a writing instrument-like housing, that is, a switch of a position indicator having a pen shaft, a portion of the pen core, that is, a portion directly in contact with the coordinate detection surface at the tip of the position indicator is in the longitudinal direction of the pen shaft. Is slightly slidable along
Some are configured to detect pen up-down information or continuous pen pressure information. On the other hand, there is a so-called side switch, that is, a switch provided at a position where a finger abuts when the operator holds the position indicator with the finger.

It is desirable that the switch piece of the side switch has an operating pressure as small as possible. This is because if the operation pressure is large, the tip of the stylus pen shifts when the side switch is operated, and there is a possibility that the coordinate values detected by the coordinate detection device may be out of order.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a stylus pen having a side switch which has a small operation pressure and does not have a possibility that coordinate values may be deviated during operation.

[0010]

In order to achieve the above object, a position indicator according to the present invention is a position indicator having a tuning circuit including a coil and a capacitor, and has a writing instrument-like housing, that is, a pen shaft. A touch sensor serving as a variable resistor as one of circuit elements forming the tuning circuit, provided with a coil forming the tuning circuit near the tip of the pen shaft; It is.

Further, two touch sensors may be provided.

[0012]

The position indicator constructed as described above is used as a position indicator of a coordinate input device called a digitizer or a tablet. Since the touch sensor serving as a variable resistance element as one of the circuit elements constituting the tuning circuit is provided at a position where the held finger abuts, when the radio wave generating means and the radio wave receiving means are provided on the tablet side, A radio wave is transmitted from the radio wave generating means, the tuning circuit provided in the position indicator is excited by the radio wave, and the reflected radio wave is received by the radio wave receiving means, and the received radio wave is transmitted to the switch of the tuning circuit. The tablet detects which operation state the radio wave originated from, and operates as a position indicator to detect the switch operation state based on the detection result. .

By providing two touch sensors, it is possible to detect both the leading and lagging information of the phase of the reflected radio wave.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the appearance of the position indicator according to the present invention. The pen shaft 11 is a writing instrument-like housing formed of, for example, a synthetic resin or the like. The most important members constituting the appearance of the position indicator according to the present invention include the touch sensor electrodes 24, 25, 28 and 29, which are different from the other parts of the pen shaft 11,
It has conductivity. The pen shaft 11 and the touch sensor electrode 24 and the like can be connected by a method such as adhesion or fitting. However, due to recent advances in plastic molding technology, they can be integrally formed as a molded product with a circuit. It is possible. For example, assuming that the pen shaft 11 is composed of three members, only one of them can be formed as a molded product with a circuit by so-called two-shot injection molding.

FIG. 1A shows the touch sensor electrodes 24 and 2
5 shows a case in which only one touch sensor switch is provided. As will be described later, other shapes of the touch sensor electrode 24 and the like are conceivable. FIG. 1 (b)
Means that, in addition to the touch sensor switch constituted by the touch sensor electrodes 24 and 25, a touch sensor switch constituted by the touch sensor electrodes 28 and 29 is also provided, and a total of two touch sensor switches are provided. Is shown. Although two switches are arranged vertically, other embodiments such as a case where they are arranged side by side and a case where they are arranged diagonally upward are also possible. For reasons described below,
Since it is desirable to prohibit the operator from using two switches at the same time, when operating one switch, it is preferable that the other switch be provided at a position where its finger does not touch.

The position pointing device according to the present invention is a "position detecting device" (Japanese Patent Publication No. 2-5380) described in the section of the prior art.
Although it is suitable for use in 5), even when using a position detecting device based on another coordinate detection principle, it can be used by providing a radio wave transmitting means, a radio wave receiving means, etc. on the position detecting device side. It is. In this case, the core 14 not only has a coefficient of friction but also a necessary member according to the principle of position detection, for example, a light emitting element or the like is used if it uses light.

The position indicator according to the present invention has a tuning circuit.
And a capacitor. The coil 12 is a main element constituting the tuning circuit, and has a function of receiving a radio wave emitted from a coordinate detecting device called a digitizer or a tablet and reflecting it. Although not shown in FIG. 1, the coil 12 is disposed inside the pen shaft 11 at a position close to the core 14.

The touch sensor electrode 24 and the like constituting the touch sensor switch are provided at the finger contact position of the pointing rod 11. By operating the switch, characteristics such as reactance, impedance or so-called Q value of the tuning circuit can be changed. Therefore, on the coordinate detection device side, the operation state of the switch is known by measuring the phase shift of the radio wave reflected from the coil 12 or the attenuation rate of the received waveform when transmission and reception are performed in a time division manner,
Switch information can be obtained.

As described above, the coil 12 plays a role of transmitting switch information to the coordinate detecting device side, and a "position detecting device" proposed by the same applicant as the present invention (Japanese Patent Publication No. 2-53805). )), A plurality of loop coils are juxtaposed in both the X and Y directions, and a selection circuit, a switching circuit, and the like are provided. Therefore, the role of the coil 12 is not only to transmit the switch information but also to transmit the position information. Become. In that case, it is desirable that an appropriate material such as ferrite is used as the magnetic core of the coil 12 to strengthen the magnetic flux penetrating the coil and to help identify the direction of the magnetic flux.

The core 14 is connected to the indicator rod 11 further ahead of the coil 12. When the position detecting device proposed by the applicant of the present invention is used, the core body 14 is made of a member which has appropriate rigidity, has an appropriate coefficient of friction with the detecting surface of the coordinate detecting device, and is somewhat sharp. If there is enough. This is because it has a function of preventing damage to the coil 12 and the ferrite core, and also has a function of visually confirming the position indicated by the position indicator. However, if the detection principle of the coordinate detection device is different, other members or components are required, as described in the section of "Prior Art". For example, in the case of a coordinate detecting device using light, an appropriate light emitting element or a reflecting member is provided.

FIG. 2 is a circuit diagram showing an embodiment in which the tuning frequency of the tuning circuit is made variable using a variable resistor. FIG.
2A and FIG. 2B show a case where the tuning frequency of the tuning circuit is made variable by adjusting the degree of the contribution of the variable resistor 21 to the total combined capacitance of the fixed capacitors 19 and 20. 2 (c) and 2 (d) show a case where the tuning frequency of the tuning circuit is made variable by adjusting the degree of contribution of the variable resistor 21 to the overall reactance of the coil 22. While the coil 12 is provided at the tip of the pointing rod and serves to send switch information to the coordinate detecting device, the coil 22 is usually formed of a so-called chip component and is provided near the rear end of the pointing rod. However, it does not generate magnetic flux for transmitting switch information, but only contributes to the adjustment of reactance.

FIG. 3 is a circuit diagram showing an embodiment in which the Q value of the tuning circuit is made variable using a variable resistor. Here, the Q value is a numerical value representing the sharpness of resonance, and as is well known, FIG.
(A) or the RLC parallel resonance circuit shown in FIG.
In the RLC series resonance circuit shown in (c), the Q value is also variable by making the resistance variable. When radio wave transmission and reception from the coordinate detection device side is performed in a time-division manner, the radio wave reflected from the position indicator side attenuates with the passage of time,
The degree of the attenuation changes according to the change in the Q value. Therefore, if the attenuation rate is measured on the coordinate detection device side, the switch information can be detected. The measurement of the attenuation rate is performed, for example, in such a manner that the level ratio between the first half and the second half of the received waveform is obtained.

FIG. 4 is a perspective view showing an electrode shape of the touch sensor. 2 and 3, a circuit using the variable resistor 21 has been proposed. In that case, a slidable piece is provided at the position of the switch 13 shown in FIG. 1 so that the resistance value of the variable resistor 21 continuously changes according to the pressing force or displacement applied to one end of the slidable piece. Is desirable. The inventor of the present invention proposes another useful embodiment. In the circuit using the variable resistor, a touch sensor is provided as one of circuit elements constituting the tuning circuit instead of the variable resistor 21. Here, the touch sensor is shown in FIG.
As shown in (b) or (c), two electrodes are provided close to each other, and are configured so that conduction between the two electrodes is achieved by touching a part of the human body, for example, the tip of a finger or the tip of a tongue. It is. Although it does not constitute a variable resistor by itself, it works as a variable resistor element including a part of the human body, but in the present invention, for convenience, the touch sensor also constitutes a tuning circuit as a variable resistor element. Let's consider it as one of the circuit elements. It is empirically known that the resistance between the touch sensor electrode 24 and the touch sensor electrode 25 can be made variable by the difference in the pressing force and pressing area, or the contact pressure and the contact area for pressing the tip of the finger or tongue. In particular, the electrode shape shown in FIG. 4A is convenient for operating with a fingertip. FIG. 4B shows an electrode shape that is convenient for adjusting the resistance value based on the contact area of the tongue. FIG. 4C shows an electrode shape which is convenient for adjusting the contact area by sliding the fingertip or tongue tip. The fact that the resistance value is adjusted with a very simple structure as compared with the above-described variable resistor largely depends on the learning ability or feedback control ability of the operator. Therefore, it can be said that the switch is useful at least for the operator having the fingertip exercise ability.

FIG. 5 is a circuit diagram showing an embodiment in which two touch sensors are provided. Coil 12, fixed capacitor 1
8, 19 and the coil 22 are the same as those depicted in FIG. 2 (a) or FIG. 2 (c). The variable resistor 21 shown in FIG.
This corresponds to the variable resistor 21 illustrated in FIG. The variable resistor 26 in FIG. 5 corresponds to the variable resistor 21 illustrated in FIG. Each of the variable resistors 21 and 26 here is constituted by the touch sensor. That is, the variable resistor 21
And 26 are touch sensors having an electrode shape as shown in FIG. 4, and therefore have infinite (several megaohms) resistance when not operated. Therefore, when the variable resistor 21 is not operated, the circuit shown in FIG. 5 functions similarly to the circuit shown in FIG. When the variable resistor 26 is not operated, the circuit shown in FIG.
Has the same function as the circuit shown in FIG. In this circuit, simultaneous operation of both the variable resistors 21 and 26 is prohibited.

FIG. 6 is a diagram showing the operation of a circuit provided with two touch sensors. In FIG. 6, an arrow A indicates a phase in a state where neither of the two variable resistors 21 and 26 each configured by a touch sensor is operated, that is, a phase in an initial state. In the initial state, the circuit shown in FIG. 6 is equivalent to a tuning circuit composed of the coil 12 and the fixed capacitor 18 for the above-described reason.

Now, let f be the resonance frequency of the tuning circuit constituted by the coil 12 and the fixed capacitor 18. For example, coil 12 is 30 microhenry, fixed capacitor 1
By making 8 about 3300 picofarads, f becomes 50
It can be set to 0 kilohertz. When the frequency of the radio wave transmitted from the radio wave transmitting means on the coordinate detection device side is fixed at f, the tuning circuit receives the radio wave of the frequency f and resonates,
Reflects radio waves of the same frequency. At this time, the waveform received by the receiving means of the coordinate detecting device is in a state where the phase shift is zero, that is, in a state shown by an arrow A in FIG.

When the variable resistor 21 is operated, the resistance value varies continuously from an infinite state (several mega ohms) to about several kilo ohms, depending on the electrode shape of the touch sensor. As the resistance value decreases, the fixed capacitor 19 decreases.
Increases the degree of contribution to the reactance of the tuning circuit, and changes in the direction of increasing the combined capacitance. Therefore, the resonance frequency decreases, and the frequency f is fixed, so that the phase of the reflected radio wave continuously changes in the direction of delay, that is, in the minus direction indicated by the arrow B in FIG.

Similarly, when the variable resistor 26 is operated, the resistance value can be continuously changed from infinite (several mega ohms) to several kilo ohms. For example, the inductance of the coil 22 is set to 2 millihenries,
When the inductance of the tuning circuit shown in FIG. 5 is set to 30.mu.
It can be changed up to about 6 microhenries. When the variable resistor 26 is operated in this manner, the combined inductance changes in a direction in which the combined inductance decreases. Therefore, the resonance frequency is continuously increased in the direction in which the resonance frequency is increased, that is, in the direction in which the phase of the reflected radio wave advances, that is, in the plus direction indicated by the arrow C in FIG. Change.

The capacitance value of the fixed capacitor 19, the coil 22
By adjusting the inductance value and the electrode shape of the touch sensor constituting the variable resistors 21 and 26, the phase information from minus 90 degrees to plus 90 degrees can be used as the switch information of the position indicator. How much the continuous phase information is finely divided and extracted as switch information is left to the way of processing on the coordinate detection device side.
It can be said that the present embodiment, in which two switches share the minus side and the plus side, improves the usability more than handling phase information up to 0 degrees. The two touch sensors are provided far enough apart so that the fingertips do not touch both, and are arranged, for example, vertically and horizontally and at positions where the fingertips abut.

[0030]

[Effects of the Invention] Since the present invention has the above-described structure, the overall weight is light and the operation pressure of the side switch is light, so that a convenient position indicator can be realized.

Further, a position indicator capable of sending a plurality of switch operating states to the coordinate detecting device by operating one switch has been realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a position indicator according to the present invention.

FIG. 2 is a circuit diagram showing an embodiment in which a tuning frequency of a tuning circuit is made variable using a variable resistor.

FIG. 3 is a circuit diagram showing an embodiment in which the Q value of a tuning circuit is made variable using a variable resistor.

FIG. 4 is a perspective view showing an electrode shape of the touch sensor.

FIG. 5 is a circuit diagram showing an embodiment in which two touch sensors are provided.

FIG. 6 illustrates an operation of a circuit provided with two touch sensors.

[Explanation of symbols]

 11 Pen shaft 12, 22 Coil 14 Core body 18, 19, 20 Fixed capacitor 21, 26 Variable resistor 23 Fixed resistor 24, 25, 28, 29 Touch sensor electrode A Initial phase B Phase when the first touch sensor is operated Of the phase C when the second touch sensor is operated

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G06F 3/03 310 G06F 3/03 325

Claims (2)

(57) [Scope of request for utility model registration] 1. A position pointing device having a tuning circuit including a coil and a capacitor, comprising: a writing instrument-like housing, that is, a pen shaft; and a coil forming the tuning circuit near a tip of the pen shaft. A position indicator comprising: a touch sensor serving as a variable resistor as one of circuit elements constituting the tuning circuit at a fingertip contact position of a pen shaft. 2. The position pointing device according to claim 1, wherein two touch sensors are provided.