JP3128948B2 - Coordinate input device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device as input means of an information processing device.

[0002]

2. Description of the Related Art Conventionally, there is no limitation on an input pen that can be used in a coordinate input device, and among a plurality of pens of one kind used, who is used to input coordinates with which pen and who uses the input pen. The pen is not identified.

[0003] Japanese Patent Laid-Open No. 60-175191 discloses a point relating to identification and protection of pen input of a coordinate input device.

[0004]

In the above-mentioned prior art, when a plurality of input users perform input using an input pen owned by a plurality of input users using one coordinate input device, the input restriction of the user is limited to password input, ID card. It was necessary to use auxiliary means such as use. Further, once the input restriction is released by the auxiliary means, anyone can input data, which has a problem in security.

[0005] It is an object of the present invention to provide an information processing apparatus using a coordinate input device for input, and checks whether input is possible at each point of pen input without using the auxiliary means.
The object of the present invention is to reduce the amount of operation of the user by performing input restriction, and to realize more strict security.

[0006]

According to the present invention, there is provided a coordinate input device which comprises a pen for designating coordinates and a sensor unit for reading the coordinates designated by the pen, and externally outputs the designated coordinates read. Alternatively, it can be achieved by providing means for outputting an ID code, reading the designated coordinates designated by the pen and the unique frequency outputted by the output means, or the ID code, and outputting the same externally.

[0007]

In the coordinate input device of the present invention, when an input is made with the input pen of the coordinate input device, the ID code set in the input pen is read simultaneously with the designated coordinate data.
Output from the coordinate input device. Thus, it is possible to determine whether the ID code is valid or invalid, and to specify the input pen used. If it is valid, the designated coordinate data output from the coordinate input device is also valid at the same time as the ID code, and the process is performed as it is. However, if the ID code is invalid, the designated coordinate data is also invalid or partially input restricted,
Achieve confidentiality.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a coordinate input device according to one embodiment of the present invention. Reference numeral 1 denotes an input pen for designating coordinates, which outputs an AC magnetic field from the tip thereof. The input pen 1 has a structure that can be separated from the coordinate input device main body, and a plurality of pens can be used with one coordinate input device. 2
Is a sensor unit, which has a structure in which matrix-shaped lead patterns 2a and 2b are arranged on a board, and when instructed by the input pen 1, outputs an induced voltage corresponding to the designated position from each lead pattern. I do. This induced voltage is an AC voltage having the same frequency as the AC magnetic field of the input pen 1. 3
Reference numerals a and 3b denote multiplexers for sequentially selecting the conductors of the conductor patterns 2a and 2b and outputting the induced voltages. Detection unit 4, sample and hold unit (S / H unit) 5, and A
The three blocks of the / D converter 6 convert the AC voltage of the sensor output into a digital quantity. 7 is a CPU unit,
The multiplexers 3a and 3b and the blocks 4 to 6 are controlled to calculate the designated coordinates of the input pen from the sensor output values,
Output to outside of the device. The CPU unit can be realized by a microprocessor system. The VFO 8 and the D / A converter 9 are blocks that control the frequency of a sensor output detection clock input to the detector 4. The operation of the coordinate input device according to the present embodiment will be described below. The input pen 1 has a structure shown in FIG. 2, and a clock from an oscillator 1a is converted into an AC magnetic field by a coil 1b disposed at the pen tip, and is output to the outside of the pen.

The oscillator 1a is connected to a power supply VC
C is powered to generate a clock of the input pen unique constant frequency f _c. In the sensor unit 2 receives an AC magnetic field of f _C of the constant frequency, the matrix of the conductor pattern 2a, the induced voltage of 2b into AC magnetic field having the same frequency f _C occurs. The induced voltage is input to the detector 4 via the multiplexer. Then, the detector 4 detects only an input voltage having the same frequency as the frequency f _vfo of the clock from the VFO 8, and outputs a DC voltage proportional to the input AC voltage.
When the input voltage has a frequency different from the frequency f _vfo , the output becomes zero. This operation is called synchronous detection. Next, in the S / H unit 5, when each conductor pattern of the sensor unit is selected by the multiplexers 3a and 3b under the control of the CPU unit by the signal line 11, the DC voltage of the output from the detection unit 4 is sampled by the signal line 13. . Further, the S / H unit 5 holds the DC voltage value sampled for a certain period of time sufficient for performing A / D conversion in the A / D conversion unit 6 in the next stage. A
The DC voltage is converted into a digital value by the
Input to the PU unit.

The CPU section can read out the magnitudes of all the induced voltages generated from the conductor pattern as digital values, and can calculate the pointing coordinate input of the pen tip from the distribution of these values.

Next, the principle of reading the ID code of the input pen will be described below. The VFO 8 is a block having a function of changing the output frequency according to the input of a DC voltage. The D / A converter 9 converts a digital input from the CPU into a DC voltage and inputs the DC voltage to the VFO 8. Input pen 1
The frequency f _{C of the} AC magnetic field output from the pen differs from pen to pen. Therefore, the CPU unit uses the VFO via the D / A conversion unit.
8 is changed to change the output frequency of the VFO 8 and input to the detector 4. The detection unit 4 has an output only when the frequency f _vfo becomes equal to the frequency f _{C of the} input pen.
When a CPU unit continuously varying the frequency f _VFO of VFO8, can recognize that the input pen unique frequency f _C of the detected frequency f _VFO output from the sensor unit. The CPU section has a conversion table of an ID code corresponding to the frequency f _C of the read input pen, and outputs the ID code to the outside of the coordinate input device from the external interface signal line 10 simultaneously with the designated coordinates of the input pen. .

FIG. 4 shows an example of an ID code conversion table. FIG. 5 shows an example of the output format of the designated coordinate values and the ID code externally output from the external interface signal line 10.

[0014] coil frequency of the detected input pen if f _ci, and outputs at the same time as the designated coordinates in the output form shown in FIG. 5 the ID code I _i based on FIG. The ID code conversion table may be stored in advance by providing a ROM in the CPU unit, for example.

In the present embodiment, the coordinate input device is used in a system for security because the ID itself is the frequency of the pen-specific AC magnetic field to transmit the designated coordinates of the input pen to the sensor unit. , Input permission / prohibition control can be easily performed.

Furthermore, in this embodiment, the unique frequency of the input pen is used as the ID code. However, as shown in FIG. 3, the input pen may be provided with a memory to store the ID code. In FIG. 3, an ID code memory 14 stores an ID code unique to the input pen. The ID code is stored in the ID code memory 1 via a signal line 16 from an external information processing device.
4 and read out to an external information processing device via a signal line 16. Reference numeral 15 denotes a battery, which serves as a power source for the oscillator 1a at the same time as backing up the ID code memory. In this case, the ID code of the input pen can be freely rewritten by an external information processing device.

Next, an application example of the coordinate input device of the present invention to an information processing device will be described.

FIG. 6 is a block diagram showing an application example of the coordinate input device of the present invention to an information processing device. In this information processing apparatus, a coordinate input device 16 is used as input means,
The output data is controlled by the input control unit 17 and the main processing unit 1
The data is processed in step S8. The ID code registration memory 19 is a memory that stores only ID codes of input pens that can permit input to the apparatus. An ID code is output from the coordinate input device 16 at the same time as the coordinate value. The input control unit 17 stores the ID code stored in the ID code registration memory 19 in advance.
It refers to all the codes and outputs the coordinate values to the main processing unit only when the ID code is registered. The input pen 1 is replaceable as described above, and a plurality of input pens can be used. Therefore, the ID code is stored in the ID code registration memory 19.
Only the input pen registered in the information processing apparatus is permitted, and when the ID code is not registered, the input is prohibited. According to the present embodiment, the input permission / prohibition control can be performed by the input pen itself as the input means without using means such as an ID code input and a security key. Can be built.

[0019]

According to the present invention, since each pen has an ID code and can be externally output together with the designated coordinates of the pen, when the coordinate input device is used as an input means of various systems, other special means are added. It is possible to provide a coordinate input device that can easily have a security function without using the coordinate input device.

Further, input permission / inhibition control can be performed by using the ID code of the pen itself as the input means without using means for exclusive security such as ID code input and security key.

[Brief description of the drawings]

FIG. 1 is a block diagram of a coordinate input device;

FIG. 2 is a cross-sectional view of an input pen,

FIG. 3 is a sectional view of an input pen possessed by an ID code memory,

FIG. 4 is a diagram showing an ID code conversion table;

FIG. 5 is a diagram showing output formats of designated coordinate values and ID codes;

FIG. 6 is a diagram showing an application of a coordinate input device to an information processing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Input pen 1a ... Oscillator 1b ... Coil 2 ... Sensor part 7 ... CPU part 8 ... VFO 9 ... D / A conversion part 14 ... ID code memory 17 ... Input control part 19 ... ID code registration memory

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 3/03 G06F 1/00

Claims (1)

(57) [Claims] 1. A pen for outputting a unique frequency, a sensor unit for reading a position indicated by the pen, a storage unit for storing a frequency at which an instruction to the sensor unit is permitted and an ID code corresponding to the frequency. A comparing unit that compares the unique frequency output by the pen with the frequency stored in the storage unit;
As a result of the comparison, when the frequency output by the pen is stored in the storage unit, the instruction of the coordinates by the pen is enabled, and the coordinates specified by the pen and the ID code corresponding to the frequency of the pen are set. A coordinate input device, comprising: a control unit that controls to output a coordinate.