JPH02252016A - coordinate input device - Google Patents

Abstract

PURPOSE:To make input work efficient by providing the coordinate input device with a means for deciding which range out of two ranges corresponding to two coordinate input modes previously set up within a range to be changed in accordance with the pen pressure of an input indicator includes a detecting phase angle outputted from a phase detecting means. CONSTITUTION:A radio wave with a prescribed frequency band is generated from a position detecting part 5 to an input pen 2 having a tuning circuit 32 consisting of a coil 28 and a capacitor, and changing its tuning frequency or phase angle around a prescribed frequency value by pen pressure, its reflected wave is detected to find out the specified position of the pen, a change in the tuning frequency or the phase angle is found out as a change from the prescribed frequency and which phase angle range corresponding to the previously determined coordinate input mode includes the phase angle is decided to switch said mode. Thereby, a cord and a battery are not required for the pen 2, the operability can be improved, the coordinate input mode can be switched only by the change of pen pressure, the specified position can be written, an erasing input mode also can be selected to erase an area, and a cursor display input mode also can be selected.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a coordinate input device that can switch and set a plurality of coordinate input modes.

(Prior Art) Conventionally, coordinate input devices that input arbitrary characters or figures by operating an input indicator on a tablet have a write input mode in which writing is performed corresponding to a specified position, and It was equipped with multiple coordinate input modes, such as an erase input mode for erasing a predetermined area corresponding to the area.

When switching between the multiple coordinate input modes mentioned above, conventional devices require only a tablet!・A menu area for mode selection is set in advance at a predetermined location within the coordinate input range of or enter a command to specify the mode from another input device such as a keyboard, or enter a command to specify the mode from another input device such as a
This was done by operating a mode selection switch or the like.

(Problem to be solved by the invention (7)) However, in the above-mentioned menu area designation, the input indicator had to be moved significantly each time the mode was switched. In modern devices, a keyboard, etc. must always be placed next to the tablet, which increases the space occupied by the device on the desk, and usually requires the keyboard, etc. to be operated with the hand on the other side of the unaccustomed arm. Furthermore, in cases where the input indicator switches, etc. are operated, information based on the operation of the switches, etc. is sent to the tablet side, so the input indicator is connected to the tablet via a cord, or the input indicator is connected to the tablet via a cord. In addition, a generator for generating an information signal using infrared rays or the like and a battery as a power source must be provided, which poses a problem in that the operability of the input indicator is significantly impaired.

The present invention solves the above problems (12) by using an input indicator that does not require a cord between it and the tablet and does not require heavy parts such as batteries, and allows the input indicator to be moved over a large distance. It is an object of the present invention to provide a coordinate input device that can switch and set modes without operating other input devices.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an input indicator having a tuning circuit whose tuning frequency or phase angle changes around a predetermined frequency in accordance with pen pressure; radio wave generating means for generating radio waves with a frequency of , radio wave detecting means for detecting radio waves reflected from the tuned circuit, and coordinates of a position designated by the input indicator based on the radio waves detected by the radio wave detecting means. A tablet comprising a coordinate detection means for determining a value and a phase angle detection means for detecting a change in the tuned frequency or phase angle in the tuning circuit as a change in the phase angle with respect to the predetermined frequency based on a radio wave detected by the radio wave detection means. a coordinate input device comprising: at least two coordinate inputs in which the phase angle detected by the phase angle detection means is set in advance within a phase angle range in which the phase angle detected by the phase angle detection means can change according to the pen pressure applied to the input indicator; A coordinate input device including a phase angle determination means for determining which phase angle range corresponds to a mode, and a mode setting means for switching and setting a coordinate input mode according to the determination result; and the coordinate input device. In coordinate input mode and 1. A coordinate input device with a write input mode in which a predetermined figure is written at a position corresponding to the coordinate values of a specified position using a coordinate input device equipped with an erasure input mode for erasing a predetermined region that has been created; and a coordinate input device in which the size of a predetermined figure or region in the two coordinate input devices is changed in accordance with a phase angle. , a coordinate input device equipped with a cursor display input mode that displays a cursor at a point corresponding to the coordinate value of a specified position as a coordinate input mode in these coordinate input devices, and a phase that changes according to pen pressure in the coordinate input device. A coordinate input device is proposed in which a range from a phase angle when no pen pressure is applied to a predetermined phase angle is assigned to a cursor display input mode.

(Function) According to the present invention, when a radio wave is generated by the radio wave generating means of the tablet, the radio wave is tuned to, that is, received by the tuning circuit of the input indicator that specifies the position on the tablet. The receiving tuned circuit emits or reflects similar radio waves. The reflected radio waves are detected by the radio wave detection means of the tablet, and the detected radio waves are further sent to the coordinate detection means of the tablet, where the coordinate values of the position designated by the input indicator are detected.

In addition, at this time, the radio waves detected by the radio wave detection means of the tablet are accompanied by deviations in frequency and phase angle depending on the pen pressure applied to the input indicator, but this is caused by the phase angle detection means of the tablet. Detected as a change. The phase angle determining means determines which coordinate input mode this phase angle corresponds to, and the mode setting means switches to a coordinate input mode according to the determination result.

Further, according to the present invention, when the pen pressure applied to the input indicator is operated such that the phase angle is within a range corresponding to the writing input mode, the writing input mode is switched and set, and the input indicator A predetermined figure is written at the specified position.

Further, according to the present invention, when the pen pressure applied to the input indicator is operated such that the phase angle is within a range corresponding to the erasure input mode, the erasure input mode is switched and set, and the input indicator A predetermined area centered around the specified position is erased.

Further, according to the present invention, when the pen pressure applied to the input indicator is changed within the phase angle range of the write input mode or the erase input mode, the size of the figure to be written or the area to be erased is changed accordingly. The height changes.

Further, according to the present invention, when the pen pressure applied to the input indicator is operated such that the phase angle is within a range corresponding to the cursor display input mode, the cursor display input mode is switched and set, and the input indicator A cursor is displayed at the position specified by the device.

Further, according to the present invention, when the input indicator is brought close to the tablet, the input mode is switched to the cursor display input mode.

(Embodiment) FIG. 1 shows an outline of an embodiment of the coordinate input device of the present invention, in which 1 is a tablet, 2 is an input indicator such as an input pen, 3 is a host computer, and 4 is a tablet. It is a display device.

FIG. 2 shows details of the tablet 1 together with a tuning circuit of the input pen 2, which will be described later. In the figure, 5 is a position detection section, 6 is a control circuit, 7 is a signal generation circuit, 8 and 9
10.11 is a transmission/reception switching circuit, 12 is an XY switching circuit, 13 is a reception timing switching circuit, 14 is a band pass filter (BPF), 15 is a wave detector, 16° and 17 are phase detection circuits. Equipment (PSD), 18.1'9
．． 20 is a low pass filter (LPF), 21.22 is a drive circuit, and 23.24 is an amplifier. Note that all of these are housed in a case 1a made of a non-metallic material.

FIG. 3 shows details of the loop coil group 5x in the X direction and the loop coil n5y in the Y direction, which constitute the position detection section 5. The loop coil group 5x in the X direction includes a large number, for example, 48 loop coils 5K -1,' 5x arranged parallel to each other and overlapping each other along the X direction.
-2,...51K -48, and Y
The loop coil group 5y in the direction includes a large number of 48 loop coils 5y-1, 5y-2, . . . 5y- arranged parallel to each other and overlapping each other along the Y direction.
48, and the loop coil group 5x in the X direction and the loop coil group 5y in the Y direction are closely overlapped with each other (however, in the drawing, they are drawn apart for easy understanding). Although each loop coil is configured with one turn here, it may be configured with multiple turns as necessary.

FIG. 4 shows the specific structure of the input pen 2, which includes a ben 111125 made of a non-metallic material such as synthetic resin, a core body 27 equipped with a ferrite chip 26, and a core body 27 that slides inside. Freely accommodated 1. The coil 28 to be obtained and the core body 27
A lead boulder 29 that holds the rear end and a lead holder 29 are attached to the pen shaft 25 in pairs. The spring 30 supports the spring 30 so as to be slightly displaceable.
and a capacitor 31.

As shown in FIG. 2, the coil 28 and capacitor 31 are connected in series to form a well-known tuning circuit 32, and the inductance of the coil 28 and the capacitance of the capacitor 31 are determined by the tuning ( (resonance) frequency is set to a value that is approximately a predetermined frequency fO. Here, when the core body 27 is held in the core holder 29, the ferrite chip 26 is located at the end of the coil 28, and when the input ben 2 is operated on the input surface etc., the current pen pressure is Accordingly, the core body 27, that is, the ferrite chip 26 moves 17, thereby causing the inductance of the coil 28 to change continuously, and the tuning frequency in the above-mentioned tuning circuit 32 to change slightly and continuously. .

The post-combi coater 3 receives (17) information on the coordinate values and phase angle of the specified position sent from the tablet 1, performs predetermined data processing, and sends the obtained information to the display device 4 for display.

Next, the operation of the device will be explained along with its configuration.
First, we will explain how radio waves are transmitted and received between the tablet 1 and the input device 2, and the signals obtained at this time.
This will be explained according to the diagram.

The control circuit 6 is composed of a well-known microprocessor or the like, and controls the signal generation circuit 7 and also controls the switching of each loop coil of the position detection section 5 via the selection circuits 8 and 9 according to the flowchart shown in FIG. Also, X
The Y switching circuit 12 and the reception timing switching circuit 13 control the switching of the coordinate detection direction, and furthermore, the output values from the low-pass filters 1g and 19.20 are converted into analog/digital (A/D), which will be described later. The arithmetic processing is executed to obtain the coordinate values of the position designated by the input ben 2, and the phase angle of the received fN signal, which will be described later, is detected and sent to the host combination coater 3.

The selection circuit 8 is for sequentially selecting one loop coil from the loop coil group 5x in the X direction, and the selection circuit 9 is for sequentially selecting a negative loop coil from the loop coil group 5y in the Y direction. Yes, each control circuit 6
Operate according to information from.

The transmission/reception switching circuit 10 alternately connects the selected negative loop coil in the X direction to the drive circuit 21 and the amplifier 23, and the transmission/reception switching circuit 11 connects the selected negative loop coil in the Y direction to the drive circuit 21 and the amplifier 23. are alternately connected to the drive circuit 22 and the amplifier 24, and these operate according to a transmission/reception switching signal, which will be described later.

The signal generation circuit 7 has a predetermined frequency fO, for example, 500kHz.
a sine wave signal A of z, a signal B whose phase is delayed by 90'' of the sine wave signal, a predetermined frequency fk, for example 15.625k
Generates a Hz transmission/reception switching signal C and reception timing No. 11. The sine wave signal A is sent directly to the phase detector 16.
The sine wave signal B is sent to either the drive circuit 21 or 22 via the XY switching circuit 12, the sine wave signal B is sent to the phase detector 17, and the transmission/reception switching signal C is sent to the transmission/reception switching circuit. Further, the reception timing signal is sent to the reception timing switching circuit 13.

Now, assuming that information for selecting the X direction is input from the control circuit 6 to the XY switching circuit 12 and the reception timing switching circuit 13, the sine wave signal A is sent to the drive circuit 21, converted to a balanced signal, and further The transmission/reception switching circuit 10 connects either the drive circuit 21 or the amplifier 23 based on the transmission/reception switching signal C1, so the signal is output from the transmission/reception switching circuit 10 to the selection circuit 8. The signal E is a signal E which outputs and does not output a signal of 5 ookuz every 32 μsec for a time T (-1/2 fk ).

The signal E is passed through the selection circuit 8 to the negative loop coil 5X-i (i-1°2, . . .
-46), the loop coil 5X-i generates a radio wave based on the signal E.

At this time, the input ben 2 is in a substantially upright state on the tablet 1,
In other words, if the radio wave is kept in use, the radio wave will be transmitted to the input vent 2.
The coil 28 is excited, and the signal E is applied to the tuned circuit 32.
An induced voltage F synchronized with is generated.

Thereafter, when the loop coil 5X-i is switched to the amplifier 23 side as the signal E enters a no-signal period, that is, the reception period, the radio wave from the loop coil 5X-i immediately disappears, but the induced voltage F is It gradually attenuates depending on the loss within the tuning circuit 32.

On the other hand, the current flowing through the tuned circuit 32 based on the induced voltage F causes the coil 28 to emit radio waves.

The radio waves are transmitted to the loop coil 5x-i connected to the amplifier 23.
In order to excite the loop coil 5 in the opposite direction, an induced voltage is generated at -i in the loop coil 5 due to the radio waves from the coil 28. The induced voltage is transferred from the transmission/reception switching circuit 10 to the amplifier 23 only during the reception period.
The received signal G is sent out to the reception timing switching circuit 13, is amplified, becomes a reception signal G, and is further sent out to the reception timing switching circuit 13.

The reception timing switching circuit 13 receives either the X direction or the selection information in the X direction, in this case, the selection information in the X direction;
A reception timing signal R which is essentially an inverted signal of the transmission/reception switching signal C is input, and the reception signal G is output during the period when the signal is high (H) level, and the reception signal G is output during the period when the signal is at the low (L) level. Since nothing is output, the signal H (substantially the same as the received signal G) is obtained as its output.

The signal H is sent to the bandpass filter 14, but since the bandpass filter 14 is a ceramic filter with a predetermined passband with the center frequency fO, several signals H are input and converge, and one of them is A signal I having an amplitude corresponding to the frequency fO of the acid component energy is sent to the detector 15 and phase detectors 16 and 17.

The signal I input to the detector 15 is detected and the signal J
After that, it is converted into a DC signal K having a voltage value, for example, Vx, by a low-pass filter 18 whose cut-off frequency is sufficiently lower than the frequency fO, and sent to the control circuit 6.

The voltage value Vx of the signal is input to the input ben 2 and the loop coil 5.
It is a value that depends on the distance between By converting the voltage value VX into digital values and performing the arithmetic processing described below on these values,
The coordinate value in the X direction of the position specified by the input ben 2 is determined.

Incidentally, the coordinate value in the X direction of the position specified by the input bench 2 is also obtained in the same manner.

On the other hand, the sine wave signals A and B are input to the phase detectors 16 and 17 as detection signals, and at this time, the signal l
Assuming that the phase of the sine wave signal A almost matches that of the sine wave signal A, the phase detector 16 outputs a signal Ll (substantially the same as the signal J) which is the positive inversion of the signal I, and the phase The detector 17 outputs a signal L2 having a symmetrical waveform on the positive and negative sides.

The signal Ll is converted by the same low-pass filter 19 into a DC signal Ml (substantially the same as the signal) having a voltage value, that is, VX, and sent to the control circuit 6.1. Further, the signal L2 is converted into a DC signal M2 by a similar low-pass filter 20 and sent to the control circuit 6, but here, since the positive side and negative side components of the signal L2 of the phase detector 17 are the same, , the voltage value of the output of the low-pass filter 20 is 0 [v].

The control circuit 6 converts the output values of the low-pass filters 19 and 20, here the signals Ml and M2, into digital values, and further uses these digital values to perform the arithmetic processing of the following equation (1). The phase angle θ between the signal added to signal 17, here I, and the sine wave signal A is determined.

θ--Tan-1(VQ/VP)...
(l) However, vP indicates a digital value corresponding to the output of the low-pass filter 19, and vQ indicates a digital value corresponding to the output of the low-pass filter 20. For example, in the case of the signal 1 described above, the voltage value of the signal M1 is Vx, but the voltage value of the signal M2 is O[V], that is, VQ-Q, so the phase angle is θ-0°.

By the way, the phase of the signal 1 is determined by the tuning circuit 3 of the input vent 2.
1. Corresponds to the tuning frequency in 2. and change. That is, when the tuning frequency in the tuning circuit 32 matches the predetermined frequency fO, an induced voltage of the frequency fO is generated in the tuning circuit 32 during both the signal transmission period and the signal reception period, and
Since an induced current synchronized with this flows, the received signal G
(or II) will match the sine wave signal A, and the phase of the signal I will also match the sine wave signal A.

On the other hand, if the tuned frequency in the tuned circuit 32 does not match the predetermined frequency fO, for example, if the frequency fl is slightly lower than the frequency fO, an induced voltage at the frequency fO is generated in the tuned circuit 32 during the signal transmission period. However, at that time, an induced current with a phase lag flows in the tuned circuit 32, and an induced voltage of approximately frequency fl and an induced current synchronized with this flow during the signal reception period, so that the received signal G (or The frequency of signal H) is slightly lower than the frequency of the sine wave signal A, and its phase is also slightly delayed.

Conversely, if the tuned frequency in the tuning circuit 32 is a frequency f2 slightly higher than the predetermined frequency fO, an induced voltage with a frequency fO (,!, is generated in the tuning circuit 32 during the signal transmission period, but at that time , an induced current with a phase lead flows through the tuned circuit 32, and an induced voltage of approximately frequency f2 and an induced current synchronized therewith flow during the signal reception period, so that the received signal G (or H) The frequency is slightly higher than the frequency of the sine wave No. 4M, and its phase is also slightly advanced.

As mentioned in 1- above, since the tuning frequency of the tuning circuit 32 changes continuously according to the writing pressure applied to the input bend 2d, the phase angle θ obtained by the above equation (1) changes continuously according to the writing pressure. It's going to change. In this embodiment, the phase angle θ is set to 309 when no pen pressure is applied to the input bend 2.
It is set in advance to be about 30'' when the maximum pen pressure is applied.

The obtained phase angle θ is sent to the host computer 3 together with the coordinate values of the specified position in the X and Y directions.

Next, details of the coordinate detection operation and phase angle detection operation at the tab 1 knot 1 and the input ben 2 will be explained according to FIGS. 6 to 10.

First, when the entire device is powered on and enters the measurement start state, the control circuit 6 sends information for selecting the X direction to the XY switching circuit 12 and the reception timing switching circuit 13, Loop coil 5x-1~5
Out of x-48, information for selecting -1 for the first loop coil 5 is sent to the selection circuit 8, and the loop coil 5x-1 is connected to the transmission/reception switching circuit 10.

The transmission/reception switching circuit 10 switches the loop coil 5x-1 to the drive circuit 21 and the amplifier 2 based on the transmission/reception switching signal C described above.
3 alternately, but in this case, the drive circuit 21 is connected to 32μ
sec, 16 sine wave signals of 500kHz as shown in FIG. 7(a) are transmitted to the loop coil 5.
(Only five of them are shown in FIG. 5 due to space limitations.)

The switching between transmission and reception is as shown in FIG. 7(b).
loop coil, here repeated 7 times for 5x-1. This seven-time transmission and reception repetition period corresponds to the - loop coil selection period (448 μsec).

At this time, an induced voltage is obtained at the output of the amplifier 523 for the - loop coil every seven reception periods, but this induced voltage is passed through the reception timing switching circuit 13 as described above. is sent to a bandpass filter 14 and averaged, and then passed through a detector 15, a phase detector 16.17, and a low-pass filter 18.1.
It is sent to the control circuit 6 via 9.20.

The control circuit 6 inputs the output value of the low-pass filter 18 after A/D conversion, and temporarily stores it as a detected voltage, for example, VXI, which depends on the distance between the input vent 2 and the loop coil 5x-1.

Next, the control circuit 6 sends information for selecting the loop coil 5x-2 to the selection circuit 8, connects the loop coil 5x-2 to the transmission/reception switching circuit 10, and connects the input valve 2 and the loop coil 5.
Detection voltage Vx2 dependent on the distance to x-2 is obtained and stored, and thereafter the loop coils 5x-3 to 5x-48
are sequentially connected to the transmission/reception switching circuit 10, and the detection voltage VXI-Vx4g (however, the detection voltage VXI-Vx4g depending on the distance in the X direction from the input bend 2 for each loop coil as shown in FIG. 7(e)) (c) shows only a part of it in analog form.)
remember.

As shown in FIG. 8, the actual detection voltage is obtained only from several loop coils in front and behind the position (xp) where the input pen 2 is placed as the center.

The control circuit 6 checks whether the voltage value of the memorized detection voltage is above a certain detection level, and if it is below the certain detection level, selects each loop coil in the X direction and performs voltage detection again. Repeatedly, if the detection level is above a certain level, proceed to the next process.

Next, the control circuit 6 sends selection information in the Y direction to the XY switching circuit 12 and the reception timing switching circuit 13, and switches the selection circuit 9 and the transmission/reception switching circuit 11 in the same manner as described above, thereby controlling the low frequency range when transmitting and receiving radio waves. Input Ben 2 obtained by A/D converting the output value of the filter 18 and each loop coil 5 in the Y direction
The detected voltage depending on the distance to y-1 to 5y-48 is temporarily stored. After that, a level check is performed in the same manner as above, and if it is below a certain detection level, the process returns to selection of each loop coil in the X direction and voltage detection, and if it is above a certain detection level, the above memorized From the voltage value, as described later, the X direction and Y direction of the specified position by the input pen 2 are determined.
Calculate the coordinate values of the direction.

Next, the control circuit 6 controls the loop coil 5x in the X direction.
1~5X-48 (or Y direction loop coil 5y-1
~5y-46), the selection circuit 8 selects information for selecting the loop coil (peak coil) from which the maximum detected voltage was obtained.
(or 9), and the transmission and reception of the radio wave is repeated a plurality of times, for example, 7 times. At that time, the output values obtained from the low-pass filters 19 and 20 are A/D converted, and the phase angle is Calculate θ.

The phase angle θ is transferred to the host computer 3 together with the X-direction and Y-direction coordinate values of the position specified by the input pen 2 described above.

When the first coordinate detection operation and phase angle detection operation are completed in this way, the control circuit 6 performs the second and subsequent coordinate detection operations, as shown in FIG. ~5x - Information for selecting only a certain number of loop coils, for example, 10 loop coils before and after the loop coil from which the maximum detected voltage was obtained, is sent to the selection circuit 8, and information is also sent to the selection circuit 8, centering on the loop coil for which the maximum detected voltage was obtained. loop coil 5y
-1 to 5y-48, centered on the loop coil where the maximum detection voltage was obtained, a certain number of 1
Send information to select only 0 loop coils to the selection circuit 9, obtain output values in the same manner as described above, and perform coordinate detection operations in the X and Y directions and phase angle detection operations for the input bend 2. The coordinate values and phase angle information of the specified position are transferred to the host computer 3, and these steps are repeated thereafter.

To explain the level check mentioned above in detail, it checks whether the maximum value of the detection voltage has reached the detection level and which loop coil has the maximum detection voltage, and then checks whether the maximum value of the detection voltage has reached the detection level. If it has not been reached, subsequent coordinate calculations etc. are stopped, and the center of the loop coil to be selected in the next coordinate detection operation and phase angle detection operation is set.

As one calculation method for determining the coordinate value in the X direction or the Y direction, for example, the coordinate value xp, the detection voltages Vxl to V
There is a method of approximating the waveform near the maximum value of x4g by an appropriate function and finding the coordinates of the maximum value of the function.

For example, in FIG. 7(e), the maximum detection voltage Vx3
By approximating the detected voltages Vx2 and VX4 on both sides thereof using a quadratic function, it can be calculated as follows (however, the coordinate value of the center position of each loop coil 5x-1 to 5x-48 is xl- x4B, and the interval is ΔX.)
. First, from each voltage and coordinate value, Vx2-a(x2-xp) +b -(2)
Vx3-a (x3-xp) + b
---・-・<3) VXA-a (x4-xp)
−1−b −−−−=−<4>. Here, a and b are constant M (a<O).

Also, x3-x2rinΔX ・・・・・・(5
)x4-x2-2Δx -----=
(B). Substituting equations (5) and (Q) into equations <3) and (4), we get xp-x2+Δx/2 ((3VX2-4Vx3+V
x4) / (Vx2-2 VX3+ VXA) 1.
...(7) becomes.

Therefore, from each detection voltage Vy+1-Vx4g, the above 1/
Extract the maximum detection voltage obtained during the ver-check and the detection voltages before and after it, and extract these and the coordinate values (known) of the loop coil immediately before the loop coil from which the maximum detection voltage was obtained. From the above 1. By performing calculations corresponding to equation (7), the coordinate value xp of the input ben 2 can be calculated.

The 10th block shows a schematic configuration of the host computer 3. In the figure, 33 is a keyboard, 34 is a read-only memory (ROM), and 35 is a random access memory (R, A
M), 36 is fu! 37 is an interface circuit of the tablet 1, 38 is an interface circuit of the display device 4, and 39 is a microprocessor (CPU).

FIG. 11 shows a mode in which a cursor is displayed at a specified position using the input pen 2 (hereinafter referred to as cursor display input mode), and a mode in which a predetermined figure, such as a circle, is written in a shape that varies in size depending on the pen pressure. (Hereinafter referred to as write input mode.)
3 shows the flow of a program in the host combination coater 3 when realizing a mode (hereinafter referred to as erasure input mode) in which predetermined areas of different sizes are erased according to pen pressure.

Moreover, FIG. 12 shows the setting range of the phase angle θ corresponding to the above program, and here, at the frequency fO,
-30''≦θ<-25' is the cursor display input mode range, -25'≦θ5'' is the write input mode range, and 5''≦θ≦30° is the erase input mode range. The writing pressure of the input ben 2 corresponding to the phase angle range of each mode described above is, for example, 0 to about 50 (g), about 5
0 to about 200 (in) and about 200 to about 400 (ar
).

Next, the operation of the host combination, :15-Y3 will be explained.

First, place the input ben 2 on the tablet and its core body 2.
When 7@ approaches downward, the above-described radio waves are exchanged between the tuning circuit 32 and the position detection section 5, and the control circuit 6 detects the coordinate values and phase angle of the specified position. It is sent to the host computer 3.

At this time, when the core body 27 of the input bevel 2 is not in contact with the input surface of the tablet 1, the phase angle by the tuning circuit 32 is -30° as described above, so the CPU 39 calculates the coordinates of the received specified position. When this is detected from the information regarding the value and phase angle, a cursor, for example "+", is displayed at a designated position on the display device 4.

When the core body 27 of the input bevel 2 is brought into contact with the input surface of the tablet 1 and the phase angle becomes 125'' or more, the CPU 3
9 converts the phase angle in the received data at that time into spread information of a predetermined figure, here the diameter of a circle proportional to the phase angle, and draws an image of a circle having the diameter at a specified position in the frame memory 36. , this is displayed on the display device 4.

The above process is repeated while the data is being transferred from the control circuit 6, so when the input ben 2 is moved while changing the pen pressure within the phase angle range of 125'' to 51'', as shown in FIG. Images 41 of circles with different diameters are lined up continuously along the locus 40 of the designated position, and an image similar to that obtained when a brush is used is obtained.Incidentally, if the process of filling out the inside of the circle is performed, Get more natural results.

Next, on the tablet 1, when the pen pressure applied to the input bend 2 becomes even greater and its phase angle becomes 35 degrees or more, the CPU 39 converts the phase angle in the received data at that time into the erase area expansion information, here Converting to a diameter of a circle proportional to the phase angle (12), the interior of the circle having the diameter (7) centered at the designated position in the frame memory 36 is erased, and this is displayed on the display device 4.

The above process is repeated while the data is transferred from the control circuit 6, so if the input pen 2 is moved while changing the pen pressure within the phase angle range of 5° to 30°, the trajectory of the specified position will be changed in the same way as above. An area along the line and having a width according to the writing pressure is erased.

Further, the data stored in the frame memory 36 is converted into a hard copy by a printer (not shown) as necessary.
It is also transmitted to other devices via a communication circuit (not shown).

According to the embodiment described above, it is possible to perform brush pen input by simply using the input pen 2 in contact with the tablet 1, and its thickness can be adjusted according to the pressure of the pen, and the eraser can be input by simply increasing the pressure of the pen. You can use the input pen 2 to select menus, and adjust the size of the erase area.
There is no need to move the cursor widely, input a command to the host computer 3 using a keyboard or the like to indicate the use of a brush pen, or input a command to indicate the use of an eraser.

In the above embodiment, the range of change in the phase angle was about -30@~30°, but the range is not limited to this, and the change in phase angle can be changed by changing the inductance as in the example. In addition to changing the capacitance value or loss (resistance).

Furthermore, in the embodiment described above, the loop coil for transmitting radio waves and the loop coil for receiving radio waves are switched between negative loop coils, but they may be provided separately.

In addition, in the above embodiment, a coordinate input device was used that transmits radio waves from the tablet side to the input indicator and receives the reflected radio waves to detect the position. It is also possible to use a well-known electromagnetic induction type coordinate input device in which the tablet side receives radio waves or receives radio waves transmitted from the input indicator side.

(Effects of the Invention) As explained above, according to the present invention, the position detection unit generates a radio wave having the predetermined frequency, and at this time, the radio wave reflected from the tuning circuit is also detected by the position detection section, and from the detected radio wave, the coordinate value of the specified position by the input indicator is determined, and the Determining a change in the tuned frequency or phase angle of the radio wave as a change in the phase angle with respect to a predetermined frequency, and further determining which phase angle range this phase angle corresponds to a preset coordinate input mode, Since the mode is set to switch to the appropriate mode, the input indicator only needs to be equipped with a tuning circuit, and no cords are required. Furthermore, heavy parts such as batteries and magnets are not required, making it easier to use during work. It has good operability, and you can switch the coordinate input mode by simply changing the pen pressure, without having to move the input indicator to the menu area or input commands from other input devices as in the past. Therefore, it becomes possible to significantly improve the efficiency of input work.

Further, according to the present invention, the writing input mode can be selected simply by applying pen pressure to the input indicator and changing the phase angle.
A predetermined figure can be written at the specified position.

Further, according to the present invention, the erase input mode can be selected by simply applying pen pressure to the input indicator and changing the phase angle, and a predetermined area centered on the specified position can be erased.

Further, according to the present invention, the size of the figure to be written or the area to be erased can be changed by simply changing the pen pressure applied to the input indicator and changing the phase angle within the range of - mode. .

Further, according to the present invention, the cursor display input mode can be selected by simply applying pen pressure to the input indicator and changing the phase angle, and the cursor can be displayed at the specified position.

Further, according to the present invention, the cursor display input mode can be selected by simply bringing the input indicator close to or lightly touching the tablet, and the designated position can be confirmed from the cursor display.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an outline of an embodiment of the coordinate input device of the present invention, Fig. 2 is a block diagram showing the details of the tablet as well as the tuning circuit of the input pen, and Fig. 3 shows the X direction and A detailed configuration diagram of the loop coil group in the X direction, Figure 4 is a cross-sectional view of the input pen, Figure 5 is a signal waveform diagram of each part of the circuit in Figure 2, Figure 6 is a flowchart of processing in the control circuit, Figure 7 (a), (b), and (c) are timing diagrams showing the basic coordinate detection operation in the control circuit, and Figure 8 shows the detection voltage obtained from each loop coil during the first coordinate detection operation. Figure 9 is a timing diagram showing the coordinate detection operation and phase angle detection operation from the second time onwards, Figure 10 is a schematic configuration diagram of the post computer, Figure 11 is a flowchart of the program in the host combination coater, and Figure 12. are diagrams showing the phase angle setting range corresponding to the program in Figure 11, and Figure 13.
The figure is a diagram showing an example of a display image when the input pen is moved while changing the writing pressure. DESCRIPTION OF SYMBOLS 1...Tablet, 2...Input pen, 3...Host combination coater, 41, Display device, 5...Position detection unit, 5X...X direction loop coil group, 5y...・X
direction loop coil group, 6... control circuit, 7... signal generation circuit, 8... X direction selection circuit, 9... X direction selection circuit, 10.11... transmission/reception switching circuit , 12・
...XY switching circuit, 13... Reception timing switching circuit, 14... Bandpass filter, 15... Detector, 16
．． 17... Phase detector, 18.19.20... Low pass filter, 28... Coil, 31... Capacitor,
32...tuned circuit.

Claims (6)

[Claims] (1) an input indicator having a tuning circuit whose tuning frequency or phase angle changes around a predetermined frequency according to pen pressure; and a radio wave generating means for generating radio waves of the predetermined frequency;
Radio wave detection means for detecting radio waves reflected from the tuning circuit; coordinate detection means for determining coordinate values of a position specified by the input indicator based on the radio waves detected by the radio wave detection means; and the radio wave detection means. A coordinate input device comprising: a tablet having phase angle detection means for detecting a change in the tuning frequency or phase angle in the tuning circuit as a change in the phase angle with respect to the predetermined frequency based on a radio wave detected by the The phase angle detected by the phase angle detection means is set in any of the phase angle ranges corresponding to at least two coordinate input modes preset within a phase angle range in which the phase angle can change depending on the pen pressure applied to the input indicator. A coordinate input device comprising: a phase angle determining means for determining whether the applicable state is met; and a mode setting means for switching and setting a coordinate input mode according to the determination result. (2) The coordinate input device according to claim 1, further comprising a write input mode in which a predetermined figure is written at a position corresponding to the coordinate values of a designated position as the coordinate input mode. (3) Coordinate input according to claim (1) or (2), characterized in that the coordinate input mode includes an erase input mode for erasing a predetermined area centered on a position corresponding to the coordinate values of the specified position. Device. (4) Claim (2) characterized in that the size of the predetermined figure or area changes in correspondence with the phase angle.
Or the coordinate input device described in (3). (5) The coordinate input device according to any one of claims (1) to (4), further comprising a cursor display input mode in which a cursor is displayed at a point corresponding to a coordinate value of a specified position as a coordinate input mode. (6) A claim characterized in that the range from the phase angle when no pen pressure is applied to a predetermined phase angle among the range of phase angles that change according to pen pressure is assigned to the cursor display input mode. (5) Coordinate input device as described.