JP4750817B2 - Position tracking signal generator and input system including the same - Google Patents

Description

  The present invention relates to a position tracking signal generation apparatus and an input system including a position tracking input apparatus that inputs information by tracking the position of the position tracking signal generation apparatus.

  The position tracking input device is a device for recognizing the position of the position tracking signal generation device where the user moves and inputting information based on the position and locus of the signal generation device. Currently, the position is realized by an input pen. It is embodied and used as a natural writing input system together with a tracking signal generator. Therefore, hereinafter, for the sake of convenience of explanation, the technical idea of the present invention will be described focusing on an example in which the position tracking signal generation device and the position tracking input device of the present invention are embodied in a natural writing input system.

  Unlike the natural writing recognition method on the tablet PC, the natural writing input system calculates a distance using a time difference between the reference signal generated by the input pen and the ultrasonic signal received by the natural writing input device, By recognizing the coordinates of the input pen and connecting the movement coordinates of the input pen, the input pen locus is recognized and input. In this case, infrared (IR), radio frequency signal (RF), or electromagnetic induction signal (EM) is used as the reference signal.

  The configuration of a conventional position tracking signal generator is shown in FIG. Referring to FIG. 1, a conventional position tracking signal generator is implemented in a pen type, and includes a power source 15 that supplies power to a main body 10 of an input pen, a reference signal generator 13 that generates a reference signal, and the like. And an ultrasonic generator 17 that generates an ultrasonic signal, and a control unit 11 that controls the reference signal generator 13 and the ultrasonic generator 17.

  In addition, it includes a pen core portion 19 that contains ink so that the user can actually record on paper, or simply includes a pen core portion 19 that penetrates the center of the main body to improve the user's writing feeling. The pen core part 19 penetrates the ultrasonic wave generating part 17 formed in a cylindrical shape, and the external housing part 20 surrounds the ultrasonic wave generating part 17 and the pen core part 19 and is coupled to the main body part 10. In this case, the ultrasonic generator 17 is generally formed of a piezo film.

  As shown in FIG. 1, the outer housing part 20 has a through-hole 22 around so that the ultrasonic wave generated by the ultrasonic wave generation part 17 is emitted to the outside.

JP 2007-179507 A.

  On the other hand, the arrival distance of the ultrasonic signal generated by the ultrasonic generator 17 of such a conventional position tracking signal generator increases as the output of the ultrasonic signal increases.

  Therefore, when the receiving sensor for receiving the ultrasonic signal of the input system is at a short distance from the signal generator for position tracking, the size of the ultrasonic signal generated by the signal generator for position tracking does not matter much. When the receiving sensor for receiving the ultrasonic signal is arranged at a long distance from the position tracking signal generator, the ultrasonic signal does not reach the ultrasonic signal receiving sensor, and the position of the position tracking signal generator is There is a problem that it cannot be traced accurately.

  In order to solve such problems, conventionally, a method for increasing the output of the ultrasonic signal has been proposed. However, if an attempt is made to increase the output of the ultrasonic signal, an ultrasonic signal is generated. In addition, the length of the piezo film surrounding the pen core portion 19 is increased, and in proportion to this, the thickness of the position tracking signal generator implemented as an input pen is increased, which is used by users. There is a problem that it is not suitable.

  A technical problem to be achieved by the present invention is to provide a position tracking signal generator capable of increasing the reach of an ultrasonic signal without increasing the thickness of the position tracking signal generator and an input using the same. To provide a system.

  The position tracking signal generator according to the present invention for achieving the above-described technical problem is a plurality of ultrasonic signal generators that are spaced apart from each other by a predetermined distance and generate ultrasonic signals according to ultrasonic control signals. A control unit that generates an ultrasonic control signal and outputs the ultrasonic control signal to each of the plurality of ultrasonic signal generation units so that the ultrasonic signals generated by the plurality of ultrasonic signal generation units are superimposed and amplified. A guide unit that is formed so as to emit an ultrasonic signal and is coupled to a main body unit that supports the ultrasonic signal generation unit while accommodating a plurality of ultrasonic signal generation units therein; .

  In addition, the control unit described above is configured so that the ultrasonic signal disposed at a short distance from the ultrasonic signal generation unit disposed at a long distance from the emission unit so that the superimposed ultrasonic signal is emitted through the emission unit. Ultrasonic control signals can be generated and output with a certain time difference in the order of the signal generator.

  The position tracking signal generator described above further includes a reference signal generator that generates a reference signal according to the reference control signal, and the controller has the same frequency as the ultrasonic signal generated by the ultrasonic signal generator. The reference control signal can be generated and output to the reference signal generation unit so that the reference signal is generated.

  On the other hand, an input system of the present invention for achieving the technical problem described above includes a signal generator for position tracking described above; a reference signal receiving sensor for receiving a reference signal generated by the signal generator for position tracking; A plurality of ultrasonic signal receiving sensors arranged to be spaced apart from each other and receiving the amplified ultrasonic signals generated by the position tracking signal generator, and a time at which the reference signal is received by the reference signal receiving sensor, A position tracking input device for measuring the position of the signal generator for position tracking using a difference from the time when each of the ultrasonic signals is received by the plurality of ultrasonic signal receiving sensors.

  On the other hand, another input system of the present invention for achieving the above-described technical problem is a plurality of ultrasonic waves that are spaced apart by a predetermined distance and each generate an ultrasonic signal according to a predetermined ultrasonic control signal. A signal generating unit and a guide unit that is formed so that an ultrasonic signal is emitted and is coupled to a main body unit that supports the ultrasonic signal generating unit while accommodating a plurality of ultrasonic signal generating units inside A position tracking signal generator including: a position tracking signal generator connected to the position tracking signal generator by wire, and superimposing and amplifying ultrasonic signals generated by a plurality of ultrasonic signal generators at a predetermined time period A position tracking input device that generates an ultrasonic control signal and outputs the ultrasonic control signal to each of a plurality of ultrasonic signal generators.

  Further, the position tracking input device described above is disposed at a short distance from the ultrasonic signal generating unit disposed at a long distance from the emitting unit so that the superimposed ultrasonic signal is emitted through the emitting unit. Ultrasonic control signals can be generated and output with a certain time difference in the order of the ultrasonic signal generator.

  Further, the position tracking input device described above includes a time when the ultrasonic control signal is output to the ultrasonic signal generators disposed at a short distance, a time when each of the ultrasonic signals is received by the plurality of ultrasonic signal reception sensors, and Can be used to measure the position of the position tracking signal generator.

  As described above, the position tracking signal generator of the present invention generates ultrasonic signals at regular time intervals so that the ultrasonic signals generated by a plurality of ultrasonic signal generators are superimposed and amplified. By doing so, there is an effect of increasing the strength of the ultrasonic signal and increasing the reach distance.

  In addition, due to the above-described structural features of the present invention, in order to increase the strength of the ultrasonic signal, which is a problem of the prior art, a position tracking signal is generated by using a large ultrasonic sensor. There is an effect of solving the problem that the thickness of the device is increased.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 2 is a diagram illustrating a configuration of a position tracking signal generator according to a preferred embodiment of the present invention. Referring to FIG. 2, the position tracking signal generator according to a preferred embodiment of the present invention is physically large and includes a main body part 200 and a guide part 300 coupled to the main body part 200.

  The main body 200 is provided with a power supply unit 230, an ultrasonic signal generation unit 240, a reference signal generation unit 220, a control unit 210, and a pen core unit 250. The power supply unit 230 supplies power to the ultrasonic signal generation unit 240, the reference signal generation unit 220, and the control unit 210. The reference signal generation unit 220 receives power supply and is input from the control unit 210. A reference signal is generated in response to the reference control signal. As the reference signal of the present invention, an infrared signal (IR), a radio frequency (RF), or an electromagnetic induction signal (EM) can be used.

  The pen core 250 may be formed at the end of the ultrasonic signal generator 240 so as to provide only a writing feeling using a general pen. In practice, the user can perform writing. The ink may be inserted into the main body 200 through the ultrasonic signal generator 240.

  When an ultrasonic control signal is input from the control unit 210, the ultrasonic signal generation unit 240 can accommodate a plurality of ultrasonic signal generation units 240a and 240b that generate an ultrasonic signal by vibration and a pen core unit 250. As described above, a core portion 242 having a cylindrical space formed at the center and a support portion 248 that is in close contact with the inner surface of the guide portion 300 and fixes the position of the ultrasonic signal generating portion 240 within the guide portion 300 are included. Consists of.

  Each of the plurality of ultrasonic signal generators 240a and 240b is preferably provided so as to be separated from each other by a certain distance L1 and surround the outer peripheral surface of the core part 242, and is provided only in a certain region of the core part 242. You can also. Each of the plurality of ultrasonic signal generators 240a and 240b converts the electric energy applied from the power supply unit 230 into vibration according to the ultrasonic control signal to generate an ultrasonic signal, and generates a piezoelectric element such as a piezo film. It is desirable to be embodied as.

  For example, FIG. 2 shows that two ultrasonic signal generators 240a and 240b are provided, but three or more ultrasonic signal generators can also be provided. In this case, each ultrasonic signal generator is generated. The parts may be arranged at different separation distances, but are desirably arranged at the same separation distance.

  In addition, as illustrated in FIG. 2, when the user performs writing using the input pen, the ultrasonic signal generation unit 240 is disposed so as to be close to the paper surface (for example, “lower stage of the input pen”). The positions of the control unit 210, the reference signal generation unit 220, and the power supply unit 230 can be arbitrarily arranged in the main body unit 200.

  On the other hand, a space is formed in the guide unit 300 so as to accommodate the ultrasonic signal generation unit 240 therein, and the guide unit 300 is coupled to the main body unit 200 while surrounding the ultrasonic signal generation unit 240 accommodated therein.

  The guide unit 300 includes a lower guide unit 310 and an upper guide unit 320, and the upper guide unit 320 is coupled to the main unit 200 in a cross section of the main unit 200 by fitting, screwing, or adhesive bonding. As can be done, a fitting or thread is formed.

  A discharge portion 330 is formed on the outer peripheral surface of the lower guide portion 310 so that the ultrasonic signals generated by the ultrasonic signal generation portions 240a and 240b accommodated in the guide portion 300 can be discharged to the outside. Yes. It is desirable that the length of the emission unit 330 be formed such that the entire ultrasonic signal generation unit (the lowest ultrasonic signal generation unit) 240a provided closest to the paper surface can be observed from the outside. That is, the ultrasonic signal generated by the lowermost ultrasonic signal generation unit 240a does not travel along the guide path formed between the ultrasonic signal generation unit 240 and the guide unit 300, but directly into the air. It is desirable that it be formed so that it can be released.

  On the other hand, the upper guide unit 320 is arranged so that the ultrasonic signal generated by the ultrasonic signal generation unit (upper ultrasonic signal generation unit) 240b accommodated therein is emitted through the emission unit 330. A guide path is formed between the ultrasonic signal generator 240b. Therefore, the ultrasonic signal generated by the upper ultrasonic signal generation unit 240 b is lowered in the paper surface direction along the guide path, and is released into the air through the emission unit 300.

  In this case, when three or more ultrasonic signal generation units are provided in the ultrasonic signal generation unit 240, the remaining ultrasonic signal generation excluding the lowermost ultrasonic signal generation unit disposed at the end in the paper plane direction The parts are accommodated so as to be surrounded by the upper guide 320, and the ultrasonic signals generated by these ultrasonic signal generation parts proceed to the emission part 330 along the guide path and are released into the air.

  On the other hand, the control unit 210 generates an ultrasonic control signal and a reference control signal so that the ultrasonic signal generation unit 240 and the reference signal generation unit 220 generate an ultrasonic signal and a reference signal, respectively, at predetermined time periods. Are output to the ultrasonic signal generator 240 and the reference signal generator 220. In this case, the control unit 210 generates and outputs the ultrasonic control signal and the reference control signal so that the ultrasonic signal and the reference signal are generated at the same frequency (that is, the same time period). The signal and the ultrasonic control signal can be output at the same time, and each can be output with a certain time difference.

  The control unit 210 controls each of the ultrasonic signal generation units 240a and 240b to generate an ultrasonic signal at a predetermined time interval, whereby the ultrasonic wave generated by each of the ultrasonic signal generation units 240a and 240b. Ultrasonic control signals are generated and output to the ultrasonic signal generators 240a and 240b so that the signals are superimposed and amplified.

  FIG. 3 is a cross-sectional view of the guide unit 300 when the guide unit 300 is coupled to the main body unit 200 according to an exemplary embodiment of the present invention. Referring to FIG. 3, when the ultrasonic signal generation unit 240 is inserted into the guide unit 300, the pen core unit 250 penetrates the core unit 242 and the lower guide unit 310 of the ultrasonic signal generation unit 240 to the outside. The main body part 200 and the upper guide part 320 are coupled so as to be in close contact with each other, and the ultrasonic waves generated by the ultrasonic signal generators 240a and 240b are blocked from flowing out to the opposite side in the paper surface direction. .

  In addition, with the ultrasonic signal generation unit 240 inserted into the guide unit 300, a guide path 350, which is a fixed space, is formed between the core 242 of the ultrasonic signal generation unit 240 and the inner surface of the guide unit 300. The ultrasonic signals generated and generated by the ultrasonic signal generators 240 a and 240 b travel along the guide path 340 and are emitted to the ultrasonic emitter 330.

  FIG. 4 is a diagram illustrating a waveform of an ultrasonic signal generated according to the first preferred embodiment of the present invention and a process in which each ultrasonic signal is superimposed and amplified. Referring more to FIG. 4, the control unit 210 generates an ultrasonic control signal that instructs generation of an ultrasonic signal at regular time intervals, and outputs the ultrasonic control signal from the emission unit 330 to the ultrasonic signal generation unit 240b at a long distance. To do.

  The ultrasonic signal generator 240b that has received the ultrasonic control signal generates an ultrasonic signal (401: see A in FIG. 4).

  The ultrasonic signal (A) generated by the ultrasonic signal generator 240b travels along the guide path 350 in the direction of the emitting unit 330 (402).

  On the other hand, when it is time for the ultrasonic signal (A) generated by the ultrasonic signal generation unit 240b to reach the ultrasonic signal generation unit 240a, the control unit 210, that is, the ultrasonic signal (A) is converted into an ultrasonic signal. When the separation distance L1 between the generators 240a and 240b advances, an ultrasonic control signal is output to the ultrasonic signal generator 240a, and an ultrasonic signal is generated with the same frequency and phase as the already generated ultrasonic signal (403). : See FIG. 4B).

  Then, the ultrasonic signal (A) and the ultrasonic signal (B) are superimposed on each other, and an amplified ultrasonic signal (A + B) is generated. Released into.

  On the other hand, the control unit 210 generates a reference control signal so that the reference signal is generated at the same frequency (that is, the same time period) as that of the ultrasonic signal regardless of the point in time when the ultrasonic signal is generated. Output to the generator 220.

  That is, the control unit 210 generates a reference control signal so that the reference signal is generated at the same frequency as the ultrasonic signal with a certain time difference from the time when the ultrasonic signal is generated, and the reference signal generating unit 220 generates the reference control signal. Can be output.

  In addition, the control unit 210 generates the reference signal at the same time as the ultrasonic signal generation unit 240b at a long distance from the emission unit 330 or the ultrasonic signal generation unit 240a at a short distance from the emission unit 330 generates the ultrasonic signal. As described above, a reference control signal instructing generation of a reference signal can be generated and output to the reference signal generator 220.

  However, in the first preferred embodiment of the present invention, the ultrasonic control signal and the reference control signal are simultaneously transmitted so that the amplified ultrasonic signal and the reference signal are simultaneously emitted from the position tracking signal generator. It outputs to the sound wave signal generation part 240a and the reference signal generation part 220, respectively.

  FIG. 5 is a diagram for explaining the overall configuration and input method of the input system according to the first preferred embodiment of the present invention.

  Referring to FIG. 5, the operation of the input system according to the preferred embodiment of the present invention will be considered. The position tracking signal generator 50a (hereinafter referred to as “input”) in which the main body 200 and the guide 300 are combined. The control unit 210 (referred to as a “pen”) generates a reference control signal and an ultrasonic control signal at the same time period (that is, the same frequency), and outputs the reference control signal and the ultrasonic signal generation unit 240 to the reference signal generation unit 220 and the ultrasonic signal generation unit 240. . As described above, the ultrasonic signal and the reference signal can be generated at the same time, or can be generated with a certain time difference.

  When a control signal is input from the control unit 210, the reference signal generation unit 220 generates a reference signal, and the ultrasonic signal generation unit 240a and the ultrasonic signal generation unit 240b of the ultrasonic signal generation unit 240 are described above. The ultrasonic signals are sequentially generated at such constant time intervals, and the generated ultrasonic signals are emitted into the air through the emission unit 330 in a state of being superimposed and amplified.

  On the other hand, the position tracking input device 60a includes a reference signal receiving sensor 40 that receives a reference signal and a plurality of ultrasonic signal receiving sensors 30a and 30b that receive ultrasonic signals. In this case, the ultrasonic signal receiving sensors 30a and 30b are provided separated by a predetermined distance.

  A method of measuring the coordinates of the input pen 50a according to the first embodiment of the present invention will be described by taking the case where the reference signal and the ultrasonic signal are generated simultaneously as an example. The (x, y) coordinates of the input pen 50a Can be obtained by solving the following equation 1 with respect to x and y.

[Equation 1]
a ² = x ² + y ²
b ² = (c−x) ² + y ²

  In Equation 1, since the infrared signal or radio frequency signal, which is the reference signal, travels at the speed of light, it is assumed that the reference signal receiving sensor 40 and the reference signal receiving sensor 40 simultaneously receive the distances a and b. The difference between the time when the reference signal is received and the time when the ultrasonic signal is received by the left ultrasonic sensor 30a and the right ultrasonic sensor 30b can be obtained by multiplying the speed of sound by the distance. Since c is a preset value, the (x, y) coordinates can be obtained by applying the a, b, and c values to Equation 1, and using the coordinate values that the input pen 50a has moved, The contents written by the user such as characters can be input.

  On the other hand, when the reference signal and the ultrasonic signal are generated at the same frequency (that is, the same time period) with a certain time difference with the input pen 50a, the above equation 1 is calculated in consideration of such a time difference. The position of the input pen 50a can be obtained by application. For example, in the input pen 50a, when the reference signal is generated α time ahead of the ultrasonic signal, the reference signal is received, and the time when the ultrasonic signal is received by each ultrasonic sensor after the α time has elapsed. Can be used to measure the position of the input pen 50a.

  FIG. 6 is a diagram for explaining the overall configuration and input method of the input system according to the second preferred embodiment of the present invention.

  The position tracking signal generator 50b according to the second embodiment includes a control unit 210, a reference signal generator 220, and a control unit 210 provided in the main body 200 in the configuration of the position tracking signal generator 50a according to the first embodiment. Except for the point that the power supply unit 230 is omitted, the structural configurations of the ultrasonic signal generation unit 240 and the guide unit 300 are the same as those in the first embodiment.

  That is, except that the control unit 210, the reference signal generation unit 220, and the power supply unit 230 are not included, the main body unit 200 includes the ultrasonic signal generation unit 240 and the pen core unit 250, and the guide unit 300. The structural configuration in which the ultrasonic signal generator 240 is coupled to the main body 200 while accommodating the ultrasonic signal generator 240 is the same as that of the first embodiment, and the ultrasonic signal generator 240 includes the ultrasonic control signal, power, Is input from the position tracking input device 60b in a wired manner, and an ultrasonic signal is generated. Therefore, only the first embodiment and other configurations and operation methods will be described.

  Referring to FIG. 6, the position tracking signal generator 50b according to the second embodiment is connected to the position tracking input device 60b in a wired manner and is supplied with power. The position tracking input device 60b generates an ultrasonic control signal that instructs the position tracking signal generator 50b (hereinafter referred to as "input pen") to generate an ultrasonic signal at a predetermined time period. And output to the input pen 50b.

  The ultrasonic signal generators 240 a and 240 b of the input pen 50 b to which the ultrasonic control signal is input generate ultrasonic signals at regular time intervals, and the amplified ultrasonic signals are transmitted via the ultrasonic emitter 330. The ultrasonic signals are received by a plurality of ultrasonic reception sensors 30a and 30b provided in the position tracking input device 60b.

  The position tracking input device 60b sets the time when the ultrasonic control signal is output to the input pen 50b as a reference time, and the time difference from the reference time to the moment when the ultrasonic signals are received by the plurality of ultrasonic reception sensors 30a and 30b. Can be used to input by measuring the position of the input pen 50b in the same manner as in the first embodiment. In this case, the reference time can be set to the time when the ultrasonic control signal is output to the ultrasonic generator 240a adjacent to the emitting unit 330.

  The position tracking signal generator of the present invention and the input system using the same have been described so far, focusing on preferred embodiments of the present invention. Those skilled in the art to which the present invention pertains can understand that the present invention can be embodied in a modified form without departing from the essential characteristics of the present invention.

  For example, in the above-described embodiment, it has been described that the ultrasonic signal generation unit 240 includes two ultrasonic signal generation units 240a and 240b. However, two or more ultrasonic signal generation units are separated from each other at regular intervals. The ultrasonic signal is generated at the time interval in which the ultrasonic signal proceeds from the uppermost ultrasonic signal generation unit to the adjacent ultrasonic signal generation unit sequentially, and the amplified ultrasonic signal is emitted. You can also

  Accordingly, the disclosed embodiments are to be considered from an illustrative rather than a limiting perspective. The scope of the present invention is shown not in the above description but in the claims, and all differences within the equivalent scope should be analyzed as being included in the present invention.

It is a figure which shows the conventional signal generator for position tracking. It is the figure which showed the structure of the signal generator for position tracking based on desirable 1st Embodiment of this invention. FIG. 3 is a cross-sectional view of a guide portion when the guide portion of FIG. 2 is coupled to the main body portion of FIG. 2 according to the first preferred embodiment of the present invention. It is a figure explaining the process in which the waveform of the ultrasonic signal produced | generated according to desirable 1st Embodiment of this invention and each ultrasonic signal are superimposed and amplified. It is a figure explaining the whole structure and input method of the input system which concern on desirable 1st Embodiment of this invention. It is a figure explaining the whole structure and input method of the input system which concern on desirable 2nd Embodiment of this invention.

Explanation of symbols

200 ... body part,
210 ... control unit,
220 ... a reference signal generator,
230 ... power supply,
240 ... an ultrasonic signal generator,
250 ... pen core,
300 ... Guide part,
330 ... discharge part.

Claims (5)

A plurality of ultrasonic signal generators that are spaced apart from each other by a predetermined distance and generate ultrasonic signals according to ultrasonic control signals;
A control unit that generates the ultrasonic control signals and outputs the ultrasonic control signals to the plurality of ultrasonic signal generation units so that the ultrasonic signals generated by the plurality of ultrasonic signal generation units are superimposed on each other and amplified; ;
A guide part that is formed so as to emit the ultrasonic signal, and is coupled to a main body part that supports the ultrasonic signal generation part while accommodating the plurality of ultrasonic signal generation parts inside;
Only including,
The controller is
In order of the superposed ultrasonic signal to be emitted through the emission unit, the ultrasonic signal generation unit arranged at a long distance from the emission unit, and then the ultrasonic signal generation unit arranged at a short distance. A position tracking signal generator for generating and outputting the ultrasonic control signal with a certain time difference . A reference signal generator for generating a reference signal in response to the reference control signal;
The controller generates the reference control signal and outputs the reference signal to the reference signal generator so that the reference signal is generated at the same frequency as the ultrasonic signal generated by the ultrasonic signal generator. The position tracking signal generator according to claim 1 . A signal generator for position tracking according to claim 2 ;
A plurality of reference signals receiving sensors that receive the reference signal generated by the position tracking signal generator and spaced apart from each other and receive the amplified ultrasonic signals generated by the position tracking signal generator. Using the difference between the time when the reference signal is received by the reference signal receiving sensor and the time when the ultrasonic signals are received by the plurality of ultrasonic signal receiving sensors, A position tracking input device for measuring the position of the position tracking signal generator;
An input system comprising: A plurality of ultrasonic signal generators that are arranged apart from each other by a predetermined distance and generate ultrasonic signals according to predetermined ultrasonic control signals;
A guide part coupled with a main body part in which an emission part is formed so as to emit the ultrasonic signal and the ultrasonic signal generation part is supported while accommodating the plural ultrasonic signal generation parts; A position tracking signal generator comprising:
The ultrasonic control signal is connected to the signal generator for position tracking by wire, and the ultrasonic control signals are amplified so that the ultrasonic signals generated by the plurality of ultrasonic signal generators are superimposed on each other at a predetermined time period. A position tracking input device that generates and outputs to each of the plurality of ultrasonic signal generators;
Only including,
The position tracking input device includes:
In order of the superposed ultrasonic signal to be emitted through the emission unit, the ultrasonic signal generation unit arranged at a long distance from the emission unit, and then the ultrasonic signal generation unit arranged at a short distance. An input system that generates and outputs the ultrasonic control signal with a certain time difference . The position tracking input device includes: a time when the ultrasonic control signal is output to the ultrasonic signal generator disposed at the short distance; a time when the ultrasonic signals are received by the plurality of ultrasonic signal reception sensors; The input system according to claim 4 , wherein a position of the position tracking signal generator is measured using a difference between the position tracking signal generator and the position tracking signal generator.

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