JP5533273B2 - Electronic writing instrument and electronic writing system - Google Patents

Description

  The present invention relates to an electronic writing instrument and an electronic writing system capable of electronically inputting user-written handwriting.

  Conventionally, for example, Patent Literature 1 discloses a technology that can electronically input user-written handwriting. This prior art pen input system includes a tablet as a recording terminal and an electronic pen as an electronic writing instrument.

  The electronic pen is used to indicate an arbitrary position on the tablet. This electronic pen incorporates a contact switch, a high frequency source, a function change switch, a frequency change device, a transmission device, and the like. The tablet receives a radio wave transmitted from the telegraph pen when the tip of the electronic pen comes into contact with the tablet, and detects the coordinates of the position indicated by the electronic pen and the frequency of the radio wave. This tablet is composed of a transparent receiving antenna and a display device.

  The user brings the pen tip of the electronic pen into contact with an arbitrary position of the tablet and moves the electronic pen. The contact switch is turned on by contact with the tablet, and a high-frequency signal having a predetermined frequency is generated from the high-frequency source. The frequency switching device divides the high-frequency signal from the high-frequency source in response to the switch signal from the function switching switch, and outputs a signal having a frequency corresponding to the switch signal to the transmission device. The transmission device wirelessly transmits the signal supplied from the frequency switching device to the tablet. A signal transmitted from the transmission device of the electronic pen is received by the transparent reception antenna of the tablet. Then, according to the frequency of the received signal, the size, color, erasure, and the like of characters and the like displayed on the display device are set.

Japanese Patent Laid-Open No. 7-200231

  In an electronic writing instrument or a recording terminal, the amount of energy of a built-in battery or the like decreases with use, so that there is a problem that the energy is exhausted during use and the use cannot be continued. In the above prior art, the frequency of the transmission radio wave can be switched according to a plurality of input functions provided in the electronic pen. However, it has not been considered to reduce the power consumed by the electronic writing instrument by providing a plurality of modes related to power consumption and using each mode properly.

  An object of the present invention is to provide an electronic writing instrument and an electronic writing system that can reduce the power consumed by the electronic writing instrument and save energy.

In order to achieve the above object, the first invention is an electronic writing instrument for inputting data corresponding to writing contents to the writing body on a recording terminal provided on the writing body, wherein the recording terminal to a first mode corresponding to when describing a signal transmitter generating and transmitting a writing signal for position detection of the electronic writing instrument, the characters in a predetermined manner to be cursive, the first mode And a second mode corresponding to a case where a symbol other than a character is written on the script, the first mode by the operation means, and the second mode. A switching determination unit that determines a mode switching state with respect to the mode, and a second unit that corresponds to the first mode with respect to the recording terminal when the switching determination unit determines that the switching state is the first mode . first send a 1 writing signal As the level parameter, or transmitted at the predetermined intervals, or to send a predetermined output, when it is determined that the switching state to the second mode by said switching determining means, the relative said recording terminal The transmission level parameter is different from the first writing signal, and the second writing signal corresponding to the second mode is used as the second transmission level parameter at an interval longer than the transmission interval of the first writing signal in the first mode. Transmission control means for controlling the signal transmission means so as to transmit or transmit at a lower output than the transmission output of the first writing signal in the first mode .

The electronic writing instrument of the first invention of the present application has a first mode and a second mode. When the user writes characters in a predetermined manner on the script , the user switches to the first mode using the operation means. The switching state to the first mode is determined by the switching determination unit, and based on the control of the transmission control unit, the signal transmission unit transmits the first writing signal for position detection as the first transmission level parameter. The recording terminal provided in the writing body detects the position of the electronic writing instrument by the first writing signal transmitted by the first transmission level parameter, and recognizes the description content on the writing body.

On the other hand, when a user describes a symbol other than characters in a manner different from that of the first writing signal , the user switches to the second mode using the operating means. The switching state to the second mode is determined by the switching determination unit, and based on the control of the transmission control unit, the signal transmission unit is a transmission level parameter different from the first writing signal and corresponds to the second mode. The second writing signal for position detection to be transmitted is transmitted as the second transmission level parameter. The recording terminal provided in the writing object detects the position of the electronic writing instrument by the second writing signal transmitted by the second transmission level parameter, and recognizes the description content in the writing object.

As described above, in the first invention of the present application, a writing signal is transmitted by selectively using two modes having different transmission level parameters. Thereby, in the second mode using the second transmission level parameter, it is possible to reduce the power consumed by the electronic writing instrument when inputting symbols. As a result, energy saving can be achieved.

The first invention, the first writing signal, as said first transmission level parameter, or transmitted at the predetermined intervals, or to send a predetermined output, the second writing signal, the second As a transmission level parameter, transmit at an interval longer than the transmission interval of the first writing signal in the first mode, or transmit at an output lower than the transmission output of the first writing signal in the first mode, The signal transmission means is controlled .

  In general, in an electronic writing instrument having a character input function and a function other than character input, in the case of character input, reducing the detection accuracy on the recording terminal side is likely to cause a practical problem. In the case of other input, there are many cases where there is no practical problem even if the detection accuracy on the recording terminal side is lowered compared to the case of character input. Therefore, in the second invention of the present application, the electronic writing instrument has a first mode corresponding to the case where characters are written on the script and a second mode corresponding to the case where descriptions other than characters are written on the script. ing.

  When the user writes characters on the script, the user switches to the first mode using the operation means. In the first mode, based on the control of the transmission control unit, the signal transmission unit transmits the first writing signal as a first transmission level parameter at a predetermined interval or a predetermined output. The recording terminal provided on the writing object detects the position of the electronic writing instrument by the first writing signal transmitted at the predetermined interval or at a predetermined output, and the user writes the position on the writing object by the movement locus of the electronic writing instrument. Recognize characters.

  On the other hand, when the user makes a description other than characters on the script, the user switches to the second mode using the operating means. In the second mode, based on the control of the transmission control means, the signal transmission means uses the second writing signal in a mode different from the first writing signal as the second transmission level parameter, and the first writing signal in the first mode. Is transmitted at an interval longer than the transmission interval of 1 or lower than the transmission output of the first writing signal in the first mode. The recording terminal provided on the writing object is a second writing transmitted at an interval longer than the transmission interval of the first writing signal in the first mode or at a lower output than the transmission output of the first writing signal in the first mode. The position of the electronic writing instrument is detected by a signal at an interval longer than that in the first mode or at an output lower than that in the first mode, and the content to be written on the writing object is recognized.

As described above, in the first invention of the present application, in the second mode, the transmission of the second writing signal is performed by decimating in time from the transmission interval of the first writing signal in the first mode, or The output is reduced from the transmission output of the first writing signal in one mode. Thereby, the power consumed by the electronic writing instrument when inputting characters other than characters can be reduced and energy saving can be achieved without reducing the recognition accuracy of characters on the recording terminal side when inputting characters.

According to a second aspect of the present invention, in the first aspect of the invention, the transmission control unit includes a contact detection unit that detects a change in the contact of the tip with respect to the writing object. When the signal is detected, the signal transmitting means is controlled to transmit the writing signal to the recording terminal at the detected timing.

  Thereby, since the writing signal corresponding to the description on the writing object can be reliably transmitted to the recording terminal, the recording terminal can perform a reliable detection without leakage.

According to a third invention, in the first or second invention, the second mode includes a plurality of modes corresponding to the contents described in the writing body, and the operating means is in the second mode. One of the plurality of modes included can be selected, the switching determination unit can determine the selection state of the mode by the operation unit, and the transmission control unit can be selected by the operation unit. The signal transmission unit is controlled so as to change the transmission interval according to which one of them is selected.

  Thereby, when the user selects the second mode and description other than characters is performed, it is possible to perform fine transmission control according to the application and reduce the power consumption of the electronic writing instrument. As a result, energy saving can be achieved more reliably.

In order to achieve the above object, a fourth invention includes a recording terminal provided in a writing body, and an electronic writing instrument for performing data input corresponding to the writing content to the writing body with respect to the recording terminal; , Wherein the electronic writing instrument generates and transmits a writing signal for detecting the position of the electronic writing instrument to the recording terminal, and a predetermined mode to the writing object. in a first mode corresponding to when describing a character, a mode different from the first mode and a second mode corresponding to a case of performing the description of symbols other than letters said to be cursive, switching It is determined that the operation mode is possible, the switching determination unit that determines the mode switching state between the first mode and the second mode by the operation unit, and the switching determination unit that is in the switching state to the first mode. If , The first writing signal corresponding to the first mode to said recording device as a first transmission level parameter, or transmitted at the predetermined intervals, or to send a predetermined output, the switching determination unit by the second When it is determined that the mode is switched to the mode, the second writing signal corresponding to the second mode is transmitted to the recording terminal, which is a transmission level parameter different from the first writing signal, and is transmitted to the recording terminal. As a level parameter , transmit at an interval longer than the transmission interval of the first writing signal in the first mode, or transmit at an output lower than the transmission output of the first writing signal in the first mode , Transmission control means for controlling the signal transmission means, the recording terminal, a plurality of coils capable of receiving the writing signal transmitted from the signal transmission means, The calculation means for performing a predetermined calculation related to the position information of the electronic writing instrument based on the reception result of the writing signal by a plurality of coils, and the calculation means are sequentially switched and connected to each coil at a predetermined cycle. And a switching connection means.

The electronic writing system of the fourth invention of the present application includes a recording terminal and an electronic writing instrument. The electronic writing instrument is provided with a first mode and a second mode.
When the user writes characters in a predetermined manner on the writing object, the user switches to the first mode using the operating means of the electronic writing instrument. Switching state to the first mode is determined by the switching determination means of the electronic writing instrument, based on the control of the transmission control unit, a signal transmitting means first writing signal for position detection to the recording terminal, a first transmission level parameter Send. The recording terminal provided in the writing body includes a plurality of coils, a switching connection unit, and a calculation unit. The first writing signal transmitted with the first transmission level parameter is received by a plurality of coils, and at that time, the switching connection means sequentially switches and connects the calculation means to each coil at a predetermined cycle, thereby connecting the first writing signal . A writing signal is acquired by the calculation means. Thereby, the recording terminal detects the position of the electronic writing instrument and recognizes the description content on the writing object.

On the other hand, the user of a different embodiment from the above first writing signal to be cursive, when performing the description of non-letter symbols, the user in the second mode by using the operation means of the electronic writing instrument Switch. The switching state to the second mode is determined by the switching determination unit of the electronic writing instrument, and based on the control of the transmission control unit, the signal transmission unit signal transmission unit is a transmission level parameter different from the first writing signal , A second writing signal for position detection corresponding to the second mode is transmitted as a second transmission level parameter. As described above, the recording terminal provided in the writing body receives the second writing signal transmitted by the second transmission level parameter by a plurality of coils, and recognizes the description content in the writing body.

As described above, in the fourth invention of this application, the electronic writing instrument transmits a writing signal by selectively using two modes having different transmission level parameters. Thereby, in the second mode using the second transmission level parameter, it is possible to reduce the power consumed by the electronic writing instrument when inputting symbols. As a result, energy saving can be achieved.

5th invention is the said 4th invention. WHEREIN: The said calculating means of the said recording terminal acquires the positional information on the said electronic writing instrument based on the reception result of the said writing signal in these coils, A frequency detection means for detecting a frequency of the writing signal received by the plurality of coils; a mode determination means for determining a mode of the electronic writing instrument based on the frequency detected by the frequency detection means; and the mode determination means. When it is determined that the electronic writing instrument is in the first mode, using the plurality of position information acquired by the position acquisition unit based on reception of the first writing signal in the plurality of coils, Character writing data generating means for generating character string data corresponding to the character string described in the writing object by the electronic writing instrument; When it is determined that the tool is in the second mode, the electronic information is obtained using at least one position information acquired by the position acquisition unit based on reception of the second writing signal by the plurality of coils. The writing instrument has a non-character string data generation means for generating data other than the character string described in the writing object.

In the fifth invention of this application, when the user writes a character on the writing object, the user switches to the first mode using the operating means of the electronic writing instrument. In the first mode, based on the control of the transmission control unit, the signal transmission unit transmits the first writing signal to the recording terminal as a first transmission level parameter at a predetermined interval or a predetermined output. The first writing signal transmitted at the predetermined interval or at a predetermined output is received by a plurality of coils of the recording terminal. Then, the frequency of the received first writing signal is detected by the frequency detecting means, and it is determined that the mode is the first mode by the mode determining means. In this case, a plurality of position information of the electronic writing instrument is acquired by the position acquisition means of the recording terminal by the user's writing operation. Then, based on the plurality of position information, the character string data generation unit generates character string data corresponding to the character string described in the script. Thereby, the recording terminal can recognize the character which the user described in the script.

  On the other hand, when the user performs a description other than characters on the writing body, the user switches to the second mode using the operation means of the electronic writing instrument. In the second mode, based on the control of the transmission control means, the signal transmission means sends the second writing signal in a mode different from the first writing signal to the recording terminal as the second transmission level parameter. Transmission is performed at an interval longer than the transmission interval of one writing signal, or at an output lower than the transmission output of the first writing signal in the first mode. As described above, the recording terminal provided on the writing object is transmitted at an interval longer than the transmission interval of the first writing signal in the first mode or at an output lower than the transmission output of the first writing signal in the first mode. The second writing signal is received by a plurality of coils. Then, the frequency of the received second writing signal is detected by the frequency detecting means, and the mode determining means determines that the second mode is set. In this case, at least one position information of the electronic writing instrument is acquired by the position acquisition means of the recording terminal by the user's writing operation. Then, based on the at least one position information, the non-character string data generation unit generates data other than the character string corresponding to the character string other than the character string described in the script. Thereby, the recording terminal can recognize the description content to the writing body.

As described above, in the fifth invention of the present application, in the second mode, in the second mode, the second writing signal is transmitted by decimating in time from the transmission interval of the first writing signal in the first mode. Alternatively, the output is reduced from the transmission output of the first writing signal in the first mode. Thereby, the power consumed by the electronic writing instrument when inputting characters other than characters can be reduced and energy saving can be achieved without reducing the recognition accuracy of characters on the recording terminal side when inputting characters.

In a sixth aspect based on the fifth aspect , if the transmission control means of the electronic writing instrument is determined to be switched to the first mode by the switching determination means, the first writing signal Is transmitted continuously, and the second writing signal is transmitted intermittently at a transmission time longer than the period when the switching determination means determines that the state is switched to the second mode. The character string data generating unit of the recording terminal controls the signal transmitting unit so that the position acquiring unit continuously receives the first writing signal by the plurality of coils. The character string data is generated using the plurality of the acquired position information, and the non-character string data generating means is configured to receive the second writing signal intermittently received by the plurality of coils. Discrete by acquisition means The acquired using at least one of the position information, and generates the data other than the character string.

In the sixth invention of this application, when the user selects the first mode on the electronic writing instrument and inputs characters, the signal transmission means continuously transmits the first writing signal based on the control of the transmission control means. Thereby, a plurality of position information of the electronic writing instrument is continuously acquired by the position acquisition means of the recording terminal, and the character string data generation means generates character string data based on the plurality of position information.

  On the other hand, when the user selects the second mode on the electronic writing instrument and inputs a character other than characters, the signal transmission means intermittently transmits the second writing signal in terms of time based on the control of the transmission control means. . Thereby, at least one position information of the electronic writing instrument is discretely acquired by the position acquisition unit of the recording terminal, and the non-character string data generation unit generates data other than the character string based on the at least one position information. At this time, in particular, in the seventh invention of the present application, the signal transmission means of the electronic writing instrument transmits the second writing signal with a transmission time longer than a cycle in which the calculation means is switched and connected to each coil in the recording terminal. Thereby, while the electronic writing instrument is transmitting the second writing signal, the coil of the recording terminal receiving the second writing signal is connected to the calculation means at least once, so that the second writing signal is surely Is obtained by the calculation means.

In a seventh aspect based on the sixth aspect , the non-character string data generation means is configured such that the position acquisition means performs discrete operations when the mode determination means determines that the electronic writing instrument is in the second mode. The electronic writing instrument includes line segment data generating means for generating line segment data corresponding to the line segment described in the writing object, using the at least one position information acquired in the step, and the computing means Is the character included in the predetermined range of the line segment represented by the line segment data generated by the line segment data generation unit out of the character string data generated by the character string data generation unit It further has character string data extracting means for extracting character string data corresponding to the column.

In the seventh invention of the present application, at least one position information of the electronic writing instrument that is discretely acquired by the position acquisition means of the recording terminal when the user selects the second mode on the electronic writing instrument and performs input other than characters. Based on the above, the line segment data generation means of the recording terminal generates line segment data corresponding to the line segment described in the script. When the line segment data is generated in response to the user's selection of the second mode in this way, the character string data extracting means of the recording terminal performs the character string included in the predetermined range of the line segment. Extract character string data corresponding to.

  Thus, after the user selects the first mode and writes a character on the script, the user selects the second mode and writes a line segment in the vicinity of the written character. The extracted character string data is extracted as a keyword. Therefore, this keyword can be used as a management tag for a file containing character string data. As a result, it is possible to perform appropriate keyword extraction in accordance with the user's intention, and high convenience can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the electric power which an electronic writing instrument consumes can be reduced and energy saving can be aimed at.

It is a perspective view showing the external appearance of the electronic writing system of one embodiment of this invention. It is a block diagram showing the functional structure of an electronic pen and a recording terminal. It is a table | surface explaining the frequency of the magnetic field generated by LC oscillation circuit according to the mode switching state by a color switch, and the state of a front-end switch. It is explanatory drawing showing the sense coil coil and proximity detection coil which are contained in the coil sheet with which a recording terminal is provided. It is explanatory drawing explaining magnetic field generation | occurrence | production in the case of character input mode. It is explanatory drawing explaining magnetic field generation | occurrence | production in the keyword setting mode or the check mark mode. It is explanatory drawing explaining the timing of the magnetic field generation | occurrence | production in the keyword setting mode. It is explanatory drawing explaining the detail of the extraction method of the keyword in a recording terminal. It is explanatory drawing explaining the detail of the extraction method of the keyword in a recording terminal. It is explanatory drawing explaining the generation | occurrence | production timing of the magnetic field generated from the electronic pen switched to the check mark mode. It is a flowchart showing the content of the control processing performed by CPU of the microcomputer of an electronic pen. It is a flowchart showing the content of the control processing performed by CPU of the microcomputer of a recording terminal. (A) is explanatory drawing which shows a part of sense coil of a X-axis direction. (B) is a graph which shows the relationship between the voltage which generate | occur | produces in the sense coil shown to Fig.4 (a), and the distance of a X-axis direction. (C) is a graph which shows the voltage difference between the mutually adjacent sense coils of the sense coil shown to Fig.4 (a). (A) is explanatory drawing which graphs and shows a position coordinate table. (B) is explanatory drawing of a position coordinate table. It is a flowchart showing the content of the control processing performed by CPU of the microcomputer of a recording terminal in order to implement | achieve the function of the keyword extraction method. It is a flowchart showing the content of the control processing performed by CPU of the microcomputer of a recording terminal in order to implement | achieve the function which selects the check box selected on the writing surface.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The electronic writing system 1 of this embodiment has the electronic pen 2 as an electronic writing tool, and the recording terminal 3, as shown in FIG. In the electronic writing system 1, the user has the electronic pen 2. The electronic pen 2 is an input device for performing data input corresponding to the content of writing on the notebook 30 to the recording terminal 3 provided on the notebook 30 as a writing object.

  In this example, the recording terminal 3 includes a sheet body 10 configured in a left-right spread shape. The sheet body 10 includes a left sheet portion 10L including a left coil sheet 100L (described later), a right sheet portion 10R including a right coil sheet 100R (described later), and an intermediate sheet portion 10M that can be bent by a user. .

  Further, the sheet body 10 is arranged so that the left and right double-sided notebooks 30 overlap. In addition, you may provide the notebook holding | maintenance part 11 as shown in FIG. 1 in the left coil sheet | seat part 10L and the right sheet | seat part 10R, respectively. Thereby, the recording terminal 3 can be integrated with the notebook 30 easily and reliably, and the handleability by the user can be improved.

  The user writes a desired handwritten character string or the like on the writing surface 31 of the notebook 30 using the electronic pen 2. When the electronic pen 2 corresponding to the writing operation is moved, electronic character string data corresponding to a character string written on the writing surface 31, that is, stroke data based on a pen position data string described later is converted into an electronic file. Saved in. At that time, the page of the electronic file can also be saved while switching, as in the case where the description is actually performed while switching the page on the writing surface 31 of the notebook 30 using ink (described later).

  When the user uses the electronic writing system 1, a power switch (not shown) provided in the electronic pen 2 is turned on. The electronic pen 2 is provided with a character input mode as a first mode corresponding to the case where the electronic pen 2 is written in a predetermined manner on the writing surface 31 of the notebook 30. This character input mode is a mode corresponding to a case where characters are written on the writing surface 31 in a predetermined manner. In addition, the electronic pen 2 has a mode different from the first mode on the writing surface 31 and two modes corresponding to the description on the writing surface 31 as a second mode corresponding to the case where symbols are described. A keyword setting mode and a check mark mode are provided. These keyword setting mode and check / mark mode are modes corresponding to the case where a description other than the characters included in the symbols is made on the writing surface 31.

  As shown in FIG. 2, the electronic pen 2 includes a mode switch 44 as an operation means, LC oscillation circuits 41a, 41b, 41c, 41d, a tip switch 42, a battery 43, a computer such as a microcomputer 40, Have

  The mode changeover switch 44 is used to switch between the three modes provided in the electronic pen 2, that is, the character input mode, the keyword setting mode, and the check / mark mode, in other words, one of the three modes. This is a switch for selecting. That is, the mode of the electronic pen 2 is switched by operating the mode switch 44. When the mode changeover switch 44 is operated, the tip 2a of the electronic pen 2 is switched, and the color described on the writing surface 31, that is, the color of ink or the color described on the electronic file is also switched. It may be. For example, when the mode is switched to the character input mode, the color described on the writing surface 31 and the electronic file is switched to black, and when the mode is switched to the keyword setting mode or the check mark mode, the color is described on the writing surface 31 and the electronic file. The color to be changed may be switched to red.

  Each of the LC oscillation circuits 41 a to 41 d is a circuit that transmits, that is, generates an alternating magnetic field (hereinafter simply referred to as “magnetic field” as appropriate) as a writing signal for detecting the position of the electronic pen 2 to the recording terminal 3. That is, the LC oscillation circuits 41a to 41d function as a signal transmission unit that generates and transmits a writing signal. Each of the LC oscillation circuits 41a to 41d includes a capacitor and a coil (not shown). Further, the LC oscillation circuits 41a to 41d are configured to be able to generate different types of magnetic fields, in this example, magnetic fields having different frequencies. You may be comprised so that generation | occurrence | production of magnetic fields, such as a mutually different modulation frequency, a modulation signal waveform, and an amplitude, is possible.

  Specifically, the LC oscillation circuit 41a generates a magnetic field with a specific frequency f1. The LC oscillation circuit 41b generates a magnetic field with a specific frequency f2. The LC oscillation circuit 41c generates a magnetic field with a specific frequency f3. The LC oscillation circuit 41d generates a magnetic field with a specific frequency f4. Hereinafter, when appropriately referring to these LC oscillation circuits 41a to 41d without distinction, they are simply referred to as “LC oscillation circuit 41”.

  The magnetic field with the specific frequency f1 and the magnetic field with the specific frequency f2 correspond to the first writing signal. The magnetic field with the specific frequency f3 and the magnetic field with the specific frequency f4 correspond to the second writing signal.

  The tip switch 42 is a switch that outputs to the microcomputer 40 a command signal S0 for changing the mode of the magnetic field generated from the LC oscillation circuit 41, that is, the frequency. For example, when the user uses the electronic pen 2 to press the tip 2 a of the electronic pen 2 against the writing surface 31 in order to write a character or the like, the tip switch 42 is turned on. Thereby, the command signal S0 is output, and the frequency of the generated magnetic field becomes the frequency f2 or f4. Note that the frequencies f2 and f4 of the magnetic field generated when the tip switch 42 is on are hereinafter referred to as “input frequencies f2 and f4” as appropriate. Further, when the user stops writing the characters or the like and moves the tip 2a of the electronic pen 2 away from the writing surface 31, the tip switch 42 is turned off. In this case, the command signal S0 is not output, and the frequency of the generated magnetic field returns to the frequency f1 or f3 before the change. The frequencies f1 and f3 of the magnetic field generated when the tip switch 42 is off are hereinafter referred to as “approach frequencies f1 and f3” as appropriate.

  The battery 43 supplies power to the microcomputer 40. The battery 43 supplies power to the microcomputer 40 when the power switch is turned on.

  The microcomputer 40 includes a CPU 40a, a ROM 40b, a RAM 40c, a counter 40d, a timer 40e, other functional units, and the like as one integrated circuit. The microcomputer 40 controls various processes executed by the electronic pen 2. The microcomputer 40 functions as transmission control means described in each claim.

  For example, the microcomputer 40 determines the mode switching state by the mode switching switch 44, in other words, the mode selection state by the mode switching switch 44. Then, the LC oscillation circuit 41 is controlled so as to switch the frequency of the generated magnetic field according to the mode switching state by the mode switching switch 44 and the state of the tip switch 42. In other words, according to the mode switching state by the mode switching switch 44 and the state of the tip switch 42, the LC oscillation circuit 41 from which the LC oscillation circuit 41 is to be generated is switched.

  Specifically, as shown in FIG. 3, when it is determined that the state is switched to the character input mode and the front end switch 42 is OFF, the microcomputer 40 sends an LC oscillation circuit to the recording terminal 3. A magnetic field having an approach frequency f1 is generated by 41a. When it is determined that the state is switched to the character input mode and the front end switch 42 is on, the microcomputer 40 causes the recording terminal 3 to generate a magnetic field of the input frequency f2 by the LC oscillation circuit 41b. If it is determined that the mode is switched to the keyword setting mode or the check mark mode and the tip switch 42 is OFF, the microcomputer 40 causes the LC oscillation circuit 41c to apply a magnetic field of the approach frequency f3 to the recording terminal 3. Is generated. If it is determined that the mode is switched to the keyword setting mode or the check mark mode and the front end switch 42 is on, the microcomputer 40 causes the LC oscillation circuit 41d to the magnetic field of the input frequency f4 to the recording terminal 3. Is generated.

  On the other hand, when the microcomputer 40 determines that the character input mode has been switched, the magnetic field having the frequency f1 or f2 is set to the recording terminal 3 as a predetermined interval, ie, an interval that is substantially negligible. The LC oscillation circuit 41 is controlled so as to continuously transmit, that is, generate at substantially zero intervals. Note that the LC oscillation circuit 41 may be controlled so that a magnetic field having the frequency f1 or f2 is generated with a predetermined output. On the other hand, when the microcomputer 40 determines that the mode is the switching to the keyword setting mode or the check / mark mode, the magnetic field with the frequency f3 or f4 is applied to the recording terminal 3 at the frequency f1 or f2 in the character input mode. The LC oscillation circuit 41 is controlled so that the magnetic field is intermittently generated at intervals longer than the transmission interval of the magnetic field, that is, the generation interval. Note that the LC oscillation circuit 41 may be controlled so that the magnetic field with the frequency f3 or f4 is generated at a lower output than the transmission output of the magnetic field with the frequency f1 or f2, that is, the generated output in the character input mode.

  Note that the interval or output itself at which the LC oscillation circuit 41 generates a magnetic field to the recording terminal 3 corresponds to the transmission level parameter described in each claim. Therefore, the predetermined interval or the predetermined output itself at which the LC oscillation circuit 41a or 41b generates the magnetic field of the frequency f1 or f2 to the recording terminal 3 corresponds to the first transmission level parameter corresponding to the character input mode. Further, the LC oscillation circuit 41c or 41d generates a magnetic field of frequency f3 or f4 to the recording terminal 3, and is longer than the magnetic field generation interval in the character input mode or lower than the magnetic field generation output in the character input mode. The output itself is a transmission level parameter different from the first transmission level parameter, and corresponds to the second transmission level parameter corresponding to the keyword setting mode or the check mark mode.

  Further, the microcomputer 40 controls the LC oscillation circuit 41 so as to change the magnetic field generation interval according to which one of the keyword setting mode and the check mark mode is selected by the mode changeover switch 44 (details). Will be described later).

  The recording terminal 3 includes a control circuit unit 20 and a battery 21 as shown in FIG. The control circuit unit 20 includes coil sheets 100L and 100R, an approach detection circuit 50, a position detection circuit 60, a peripheral circuit 70, a computer such as a microcomputer 80, and a switch unit 90. The microcomputer 80, the approach detection circuit 50, the position detection circuit 60, and the peripheral circuit 70 are connected via a signal line so that transmission is possible. The coil sheets 100L and 100R, the approach detection circuit 50, and the position detection circuit 60 are connected via a signal line. The approach detection circuit 50, the position detection circuit 60, the peripheral circuit 70, and the battery 21 are connected by a power line via the switch unit 90.

  The microcomputer 80 includes a CPU 80a, a ROM 80b, a RAM 80c, a counter 80d, a timer 80e, other A / D conversion function units, an interrupt function unit, and the like as one integrated circuit. The microcomputer 80 controls various processes executed by the recording terminal 3 and controls the operation states of the approach detection circuit 50, the position detection circuit 60, and the peripheral circuit 70. Further, the microcomputer 80 performs a predetermined calculation related to the coordinate data of the electronic pen 2 based on the reception (described later) results of magnetic fields in the sense coils X1 to Xm and Y1 to Yn of the later-described sense coil unit 110 (details are given below). Later). The microcomputer 80 functions as a calculation means described in each claim.

  For example, the microcomputer 80 switches between a sleep mode and a normal mode. The sleep mode is a mode in which the recording terminal 3 enters a standby state in the low power consumption mode based on a signal from the approach detection circuit 50. The normal mode is a mode in which the recording terminal 3 performs a normal operation of detecting a magnetic field generated by the electronic pen 2 and storing stroke data such as character string data described later. The circuits 50, 60, and 70 are switched between the sleep mode and the normal mode by a signal from the microcomputer 80. In the sleep mode, the circuits 50, 60, and 70 are in a dormant state, and no power is consumed. Further, the microcomputer 80 itself consumes less power in the sleep mode. As will be described later in the sleep mode, when the interrupt process by the approach signal S24 from the approach detection circuit 50 is executed in the sleep mode, the mode is switched to the normal mode. Details of switching between the normal mode and the sleep mode will be described later.

  As shown in FIG. 4, the coil sheets 100 </ b> L and 100 </ b> R include a sense coil unit 110 and an approach detection coil unit 120. That is, the sense coil part 110 and the proximity detection coil part 120 arranged as shown in FIG. 4 are resin-molded into, for example, a rectangular thin plate shape to constitute the coil sheets 100L and 100R. In FIG. 4, the sense coil unit 110 is indicated by a broken line, and the proximity detection coil unit 120 is indicated by a solid line.

  As shown in FIG. 4, the sense coil unit 110 includes m loop-shaped sense coils X1 to Xm arranged in the x-axis direction and n loop-shaped sense coils Y1 to Ym arranged in the y-axis direction. Yn. The sense coils X1 to Xm and the sense coils Y1 to Yn are arranged in an orthogonal positional relationship. The sense coils X1 to Xm and Y1 to Yn each function as a coil described in each claim. The sense coils X1 to Xm and Y1 to Yn are formed of, for example, a copper wire having an insulating coating layer formed on the surface. The sense coils X1 to Xm and Y1 to Yn are connected to the electronic pen by magnetic induction with the magnetic field of the input frequency f2 or f4 generated from the LC oscillation circuit 41b or 41d when the tip switch 42 of the electronic pen 2 is on. 2 generates a signal S1 (see FIG. 2) for inputting data to the recording terminal 3. The magnetic induction with the magnetic field generated from the LC oscillation circuit 41 of the electronic pen 2 substantially corresponds to the reception of the writing signal transmitted from the LC oscillation circuit 41 of the electronic pen 2. Further, the sense coils X1 to Xm and Y1 to Yn are connected to a multiplexer 62 of a position detection circuit 60 described later.

  Each of the sense coils X1 to Xm is formed in a substantially rectangular shape including a side having a width P1 in the x-axis direction and a side having a length P2 in the y-axis direction longer than P1. Each of the sense coils X1 to Xm is arranged continuously in the x-axis direction at a predetermined constant pitch. For example, the adjacent sense coils X1 to Xm are overlapped with each other at a half pitch of P1.

  Each of the sense coils Y1 to Yn is formed in a substantially rectangular shape having a side having a width P3 in the x-axis direction and a side having a length P1 in the y-axis direction shorter than P3. Each of the sense coils Y1 to Yn is continuously arranged in the y-axis direction at a predetermined constant pitch. For example, the adjacent sense coils Y1 to Yn are overlapped at a pitch of 1/2 of P1.

  In FIG. 4, for the sake of simplicity, the sides of the sense coils X1 to Xm and the sense coils Y1 to Yn are not overlapped for convenience. Absent.

  The approach detection coil unit 120 generates a signal S2 (see FIG. 2) by magnetic induction with the magnetic field of the approach frequency f1 or f3 generated from the LC oscillation circuit 41a or 41c with the tip switch 42 of the electronic pen 2 turned off. Occur. As shown in FIG. 4, unlike the sense coil unit 110, the proximity detection coil unit 120 is configured by a single loop-shaped coil.

  Returning to FIG. 2, the approach detection circuit 50 detects that the electronic pen 2 has approached the recording terminal 3 based on the signal S <b> 2 generated by the approach detection coil unit 120. As shown in FIG. 2, the approach detection circuit 50 includes a band-pass filter 52 whose pass frequencies are f1 and f3, an amplifier circuit 54, a rectifier circuit 56, and a duration detection circuit 58.

  The band pass filter 52 removes an unnecessary band from the input signal S2. The band-pass filter 52 passes the signal S21 having the approach frequency f1 or f3 generated from the LC oscillation circuit 41a or 41c when the tip switch 42 of the electronic pen 2 is off.

  The amplifying circuit 54 amplifies the signal S21 that has passed through the bandpass filter 52 to obtain a signal S22. The rectifier circuit 56 performs amplitude detection of the signal S22 amplified by the amplifier circuit 54.

  The continuity detection circuit 58 prevents malfunction due to noise and removes the approach frequency f1 and f3 components. Therefore, the continuation detection circuit 58 detects whether the signal S23 detected by the rectifier circuit 56 has continued for a predetermined period of time, and determines whether the amplitude of the signal S23 exceeds a predetermined threshold value. . When it is detected by the continuation detection circuit 58 that the signal S23 having the approach frequency f1 or f3 continues for a certain time and the amplitude exceeds the threshold value, a release signal S24 is output to the microcomputer 80. The cancel signal S24 is a signal for canceling the standby state, that is, the sleep mode. Therefore, when the electronic pen 2 comes close to the coil sheets 100L and 100R, the release signal S24 is output.

  The position detection circuit 60 is a known circuit that detects coordinates representing positions on the coil sheets 100L and 100R where the electronic pen 2 is present. As shown in FIG. 2, the position detection circuit 60 includes a multiplexer 62 (hereinafter referred to as “MUX 62” as appropriate), an amplifier circuit 64, and a rectifier circuit 66.

  The MUX 62 sets each of the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110 based on a coil selection signal S3 from the microcomputer 80 to a predetermined cycle T (a scan cycle T shown in FIG. 5 and FIG. 6 described later). Select one by one sequentially. The MUX 62 is generated by magnetic induction with the magnetic field of the input frequency f2 or f4 generated from the LC oscillation circuit 41b or 41d when the tip switch 42 of the electronic pen 2 is on in the selected sense coil unit 110. The signal S1 is input and the corresponding signal S11 is output.

  The amplifier circuit 64 amplifies the signal S11 input from the MUX 62. The signal amplified by the amplifier circuit 64, that is, the electronic pen input detection signal S12 is input to the microcomputer 80. Another signal S13 amplified by the amplifier circuit 64 is input to the rectifier circuit 66. The rectifier circuit 66 amplitude-detects the input signal S13, smoothes it, and converts it into a DC signal. The signal S14 subjected to amplitude detection by the rectifier circuit 66 is input to the microcomputer 80.

  The signal S14 is input to the microcomputer 80 when the MUX 62 sequentially selects the sense coils X1 to Xm, Y1 to Yn of the sense coil unit 110 and outputs the signal S11 every predetermined period T. Is done. This substantially corresponds to the MUX 62 switching and connecting the microcomputer 80 to each of the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110 in sequence at the predetermined period T. That is, the MUX 62 functions as a switching connection unit described in each claim.

  As described above, the microcomputer 80 has an A / D conversion function, and converts the input signal S14 after amplitude detection into a digital signal. At this time, a position coordinate table described later is stored in the ROM 80b of the microcomputer 80. The microcomputer 60 calculates the x coordinate in the x axis direction and the y coordinate in the y axis direction by applying the position coordinate table to the digital signal. The calculated coordinate data is stored in a flash memory 72 of the peripheral circuit 70 described later. Details of this coordinate data calculation method will be described later.

  As shown in FIG. 2, the peripheral circuit 70 includes a flash memory 72, a communication interface 74, and a display unit 76.

  An electronic file is prepared in advance in the flash memory 72, and the coordinate data calculated by the recording terminal 3 is written and stored in the electronic file. The communication interface 74 is an interface for providing stroke data based on a pen position data sequence including a plurality of coordinate data stored in the flash memory 72 to an external device such as a personal computer. Specifically, the communication interface 74 is, for example, a USB interface for Universal Serial Bus (USB) connection, a memory card slot such as an SD card, or a wireless or wired network interface.

  The display unit 76 is configured by a liquid crystal display (LCD), for example, and displays predetermined information related to the operation state of the recording terminal 3 such as the remaining amount of the battery 21.

  The switch unit 90 selectively connects the battery 21 to the approach detection circuit 50 or the position detection circuit 60 and the peripheral circuit 70 in accordance with the control signal Sa from the microcomputer 80.

  A feature of the present embodiment having the above configuration is that when the electronic pen 2 is in the character input mode, a magnetic field having a frequency f1 or f2 is continuously generated from the LC oscillation circuit 41a or 41b to the recording terminal 3 to When the pen 2 is in the keyword setting mode or the check mark mode, the magnetic field having the frequency f3 or f4 from the LC oscillation circuit 41c or 41d is applied to the recording terminal 3 at an interval longer than the generation interval of the magnetic field in the character input mode. It is to generate intermittently. The details will be described below with reference to FIGS. In the graphs shown in FIGS. 5 and 6, the horizontal axis represents time.

  As described above, the electronic pen 2 includes a character input mode, a keyword setting mode, and a check / mark mode. When it is desired to write characters on the writing surface 31 of the notebook 30, the user switches the mode to the character input mode using the mode changeover switch 44 of the electronic pen 2. Then, characters are written on the writing surface 31.

  In the character input mode, a magnetic field is continuously generated from the LC oscillation circuit 41 of the electronic pen 2 as shown in FIG. Specifically, when the tip 2a of the electronic pen 2 is not in contact with the writing surface 31 and the tip switch 42 is turned off, a magnetic field having an approach frequency f1 is continuously generated from the LC oscillation circuit 41a. When the tip 2a of the electronic pen 2 is in contact with the writing surface 31 and the tip switch 42 is on, a magnetic field with an input frequency f2 is continuously generated from the LC oscillation circuit 41b.

  Therefore, when the electronic pen 2 is in the character input mode, the recording terminal 3 continuously detects the coordinate data of the electronic pen 2 by the magnetic field continuously generated from the LC oscillation circuit 41 of the electronic pen 2. The

  On the other hand, when it is desired to write other than characters on the writing surface 31, the user switches the mode to the keyword setting mode or the check / mark mode using the mode changeover switch 44 of the electronic pen 2. Then, other than characters are written on the writing surface 31. That is, when the mode is switched to the keyword setting mode, a line segment is described in a predetermined range of the character string described on the writing surface 31 in the character input mode. When the mode is switched to the check / mark mode, a check line is written or filled in a check box or mark sheet provided in advance on the writing surface 31.

  In the keyword setting mode, as shown in FIG. 6, the LC pen oscillation of the electronic pen 2 is generated intermittently by alternately repeating the generation time t1 when the magnetic field is generated and the non-generation time t2 when the magnetic field is not generated. This is done by the circuit 41. That is, the generation of the magnetic field from the LC oscillation circuit 41 is performed during the generation time t1, and the generation of the magnetic field from the LC oscillation circuit 41 is stopped during the non-generation time t2. Specifically, when the tip 2a of the electronic pen 2 is not in contact with the writing surface 31 and the tip switch 42 is turned off, the magnetic field of the approach frequency f3 is intermittently generated from the LC oscillation circuit 41c. When the tip 2a of the electronic pen 2 is in contact with the writing surface 31 and the tip switch 42 is on, a magnetic field with an input frequency f4 is intermittently generated from the LC oscillation circuit 41d.

Therefore, when the electronic pen 2 is in the keyword setting mode, the recording terminal 3 detects the coordinate data of the electronic pen 2 discretely by the magnetic field generated intermittently from the LC oscillation circuit 41 as described above. The

  At this time, the generation time t1 when the magnetic field is generated with respect to the recording terminal 3 is scanned by the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110 on the recording terminal 3 side as shown in FIG. Is set to a time longer than the scanning cycle T in which (described later) is performed. That is, in the keyword setting mode, the magnetic field having the frequency f3 or f4 is generated intermittently and with a transmission time that is longer than the scan period T, that is, the generation time. For this reason, the sense coils X1 to Xm and Y1 to Yn are selected at least once by the microcomputer 80 of the recording terminal 3 during the generation time t1 when the magnetic field is generated from the electronic pen 2. Yes.

  In addition, when the electronic pen 2 is in the keyword setting mode, when the tip switch 42 is switched on / off, the timing is the same even during the non-occurrence time t2 when the magnetic field is not generated for the recording terminal 3. A magnetic field is generated from the LC oscillation circuit 41. The details will be described below with reference to FIGS. 7 (a) and 7 (b). In the graph shown in FIG. 7B, the vertical axis represents the frequency of the magnetic field generated and the horizontal axis represents time.

  As shown in FIG. 7A, the writing surface 31 of the notebook 30 has a character string CH composed of “sentence”, “character”, “enter”, and “force”. This character string CH is a character string described in the character input mode. In this character string CH, the line segment UL1 is described in a predetermined range (described later) of “sentence” and “character”, and the line segment UL2 is described in a predetermined range (described later) of “ON” and “force”. Yes. Each of these line segments UL1 and UL2 is a line segment described in the keyword setting mode, and is described with one stroke, that is, one stroke.

  When the line segments UL1 and UL2 are written by the electronic pen 2, the tip 2a of the electronic pen 2 is brought into contact with the writing surface 31 at the position of the point p1, and the contact is released at the position of the point p2, that is, separated from the writing surface 31. Yes. After that, the writing surface 31 is contacted again at the position of the point p3 and is separated from the writing surface 31 at the position of the point p4. In such a case, the tip switch 42 of the electronic pen 2 is switched from OFF to ON at the position of the point p1, and is switched from ON to OFF at the position of the point p2. After that, it switches from off to on again at the position of point p3 and switches from on to off at the position of point p4.

  The generation behavior of the magnetic field from the LC oscillation circuit 41 of the electronic pen 2 in such a case is as shown in FIG. 7B at a timing tp1 when the tip switch 42 is turned on from the off position at the point p1. A magnetic field having an input frequency f4 is generated from the LC oscillation circuit 41d to the recording terminal 3. After that, while the front end switch 42 is on, the LC oscillation circuit 41d performs intermittent generation that alternately repeats the generation time t1 and the non-generation time t2 for generating the magnetic field of the input frequency f4 for the recording terminal 3. Then, at the timing tp2 when the front end switch 42 is turned off from the on position at the point p2, a magnetic field having an approach frequency f3 is generated from the LC oscillation circuit 41c to the recording terminal 3. While the front end switch 42 is OFF, the LC oscillation circuit 41c performs intermittent generation that alternately repeats the generation time t1 and the non-generation time t2 at which the magnetic field of the approach frequency f3 is generated with respect to the recording terminal 3. Then, at the timing tp3 when the front end switch 42 is turned on from the off position at the point p3, a magnetic field of the input frequency f4 is generated from the LC oscillation circuit 41d to the recording terminal 3. After that, while the front end switch 42 is on, the LC oscillation circuit 41d performs intermittent generation that alternately repeats the generation time t1 and the non-generation time t2 for generating the magnetic field of the input frequency f4 for the recording terminal 3. Then, at the timing tp4 when the front end switch 42 is turned off from on at the position of the point p4, the magnetic field of the approach frequency f3 is generated from the LC oscillation circuit 41c to the recording terminal 3.

  As described above, when the electronic pen 2 is in the keyword setting mode, when the tip switch 42 is switched from OFF to ON, the timing does not occur during the non-occurrence time t2 when no magnetic field is generated for the recording terminal 3. At that timing, a magnetic field with an input frequency f4 is generated from the LC oscillation circuit 41d. Further, when the tip switch 42 is switched from on to off, the magnetic field of the approach frequency f3 is generated from the LC oscillation circuit 41c at that timing even during the non-generation time t2 when the magnetic terminal is not generated at the timing. Generated.

  Accordingly, the recording terminal 3 can reliably acquire coordinate data described by the electronic pen 2 and corresponding to the start point and end point positions of each line segment UL.

  Next, the details of the keyword extraction method in the recording terminal 3 will be described with reference to FIGS. 8 (a) to 8 (d) and FIGS. 9 (a) to 9 (d).

  FIG. 8A shows a character string CHi composed of “a”, “i”, “u”, “e”, “o”, “ka”, “sa”, and the vicinity of the character string CHi on the electronic file. This represents the line segment ULj. This character string CHi is a plurality of coordinate data obtained continuously based on the magnetic field continuously generated from the electronic pen 2 switched to the character input mode and the electromagnetic induction between the sense coil unit 110 of the recording terminal 3. Is character string data based on a pen position data string including the character string, that is, a character string represented by stroke data. This line segment ULj is a plurality of coordinate data acquired intermittently based on electromagnetic induction between the magnetic field intermittently generated from the electronic pen 2 switched to the keyword setting mode and the sense coil unit 110 of the recording terminal 3. By sequentially connecting point a, point b, point c, point d, point e, point f, point g, point h, point i, point j, point k, point l on the electronic file corresponding to It is the line segment represented.

  In the present embodiment, character string data corresponding to the character string CHi included in the predetermined range of the line segment ULj on the electronic file is extracted as a keyword from the character string data. Specifically, for each character included in the character string CHi, the lowermost part of a range cut out as a character (a range surrounded by a dotted line in the figure, hereinafter referred to as “character range” as appropriate), and a line segment ULj Among them, the minimum distance di between the portion corresponding to the horizontal dimension Li of the character range is smaller than the vertical dimension Hi of the character range, and the line segment ULj is related to the horizontal dimension Li of the character range. It is determined whether or not the dimension Wi of the part is larger than one half of the horizontal dimension Li of the character range. In the example shown in FIG. 8A and FIG. 8B, the above Li, di, Hi, and Wi for the character “A” are represented. Then, among the characters included in the character string CHi, the character string data corresponding to the character string composed of characters satisfying the above two conditions, that is, di <Hi and Wi> Li / 2 is extracted as a keyword. Is done. Accordingly, since “a” is di <Hi and Wi> Li / 2, the character data corresponding to “a” is extracted as a keyword.

  Similarly, for “I”, “U”, “E”, and “O” included in the character string CHi shown in FIG. 8A, FIG. 8C, FIG. 8D, As shown in FIGS. 9A and 9B, di <Hi and Wi> Li / 2. Therefore, the character data corresponding to “I”, “U”, “E”, and “O” are extracted as keywords.

  Further, “sa” included in the character string CHi shown in FIG. 8A does not satisfy di <Hi and Wi> Li / 2 as shown in FIG. 9C. That is, di ≧ Hi and Wi> Li / 2. Therefore, the character data corresponding to “sa” is not extracted as a keyword.

  Further, “ka” included in the character string CHi shown in FIG. 8A does not satisfy di <Hi and Wi> Li / 2 as shown in FIG. 9D. That is, di <Hi and Wi ≦ Li / 2. Therefore, character data corresponding to “ka” is not extracted as a keyword.

  As described above, with respect to the character string CHi shown in FIG. 8A, the characters composed of “a”, “i”, “u”, “e”, and “o” satisfying di <Hi and Wi> Li / 2. Character string data corresponding to the column is extracted as a keyword.

  Next, the generation timing of the magnetic field generated from the electronic pen 2 switched to the check mark mode will be described with reference to FIGS. 10 (a) and 10 (b). In the graph shown in FIG. 10B, the vertical axis represents the frequency of the magnetic field generated and the horizontal axis represents time.

  As shown in FIG. 10A, on the writing surface 31 of the notebook 30, three check boxes Cb1, Cb2, and Cb3 are provided in advance. Of these check boxes Cb1 to Cb3, a check line Cs is described for the check box Cb1. The check line Cs is a line segment described in the check mark mode, and is described with a single stroke, that is, with one stroke.

  When the check line Cs is written by the electronic pen 2, the tip 2a of the electronic pen 2 is in contact with the writing surface 31 at the position of the point p5 and is separated from the writing surface 31 at the position of the point p6. In such a case, the tip switch 42 of the electronic pen 2 is switched from OFF to ON at the position of the point p5, and is switched from ON to OFF at the position of the point p6.

  The generation behavior of the magnetic field from the LC oscillation circuit 41 of the electronic pen 2 in such a case is as shown in FIG. 10B at the timing tp5 when the tip switch 42 is turned on from the off position at the point p5. A magnetic field having an input frequency f4 is generated from the LC oscillation circuit 41d to the recording terminal 3. Note that the magnetic field at this time is generated only during the generation time t1 described above. Then, at the timing tp6 when the front end switch 42 is turned off from the on position at the point p6, the magnetic field of the approach frequency f3 is generated from the LC oscillation circuit 41c to the recording terminal 3. The magnetic field at this time is also generated only during the generation time t1 described above.

  That is, when the electronic pen 2 is in the check mark mode, a magnetic field is generated from the LC oscillation circuit 41 at the timing when the tip switch 42 is switched on / off. Specifically, when the tip switch 42 is switched from OFF to ON, a magnetic field of the input frequency f4 is generated from the LC oscillation circuit 41d at that timing. When the tip switch 42 is switched from ON to OFF, the LC oscillation circuit is switched at that timing. A magnetic field having an approach frequency f3 is generated from 41c. That is, the magnetic field with the input frequency f4 is generated at the start point of the check line Cs, and the magnetic field with the approach frequency f3 is generated at the end point p6.

  Therefore, the recording terminal 3 can reliably acquire the coordinate data of the position corresponding to the start point and end point of each check line Cs described by the electronic pen 2.

  Next, details of the method for selecting the check box Cb in the recording terminal 3 will be described with reference to FIG.

  FIG. 10C shows check boxes Cb1 to Cb3 and a line segment Lj on the electronic file. This line segment Lj includes the magnetic field generated at the positions of points p5 and p6 of the check line Cs shown in FIG. 10A from the electronic pen 2 switched to the check mark mode, and the sense coil portion of the recording terminal 3. 110 is a line segment represented by connecting point m and point n on the electronic file corresponding to two coordinate data acquired intermittently based on electromagnetic induction with 110.

  In the present embodiment, among the plurality of check boxes Cb, the check box Cb that is closest to the line segment Lj on the electronic file is selected as the check box Cb selected on the writing surface 31. Specifically, for each check box Cb on the electronic file, the minimum distance dm between the line segment Lj and the center point cp of the check box Cb on the electronic file is calculated, and the calculated minimum distance dm is the smallest. The check box Cb is selected as the check box Cb selected on the writing surface 31.

  In the example shown in FIG. 10C, on the electronic file, the minimum distance dm1 related to the check box Cb1, the minimum distance dm2 related to the check box Cb2, and the minimum distance dm3 related to the check box Cb3 increase in this order. That is, dm1 <dm2 <dm3. Therefore, in this case, among the check boxes Cb1 to Cb3, the check box Cb1 having the smallest minimum distance dm from the line segment Lj is selected as the check box Cb selected on the writing surface 31.

  The contents of the control processing performed by the CPU 40a of the microcomputer 40 of the electronic pen 2 in order to realize the functions described above will be described with reference to FIG.

  In FIG. 11, this process is started when the user turns on the electronic pen 2. First, in step SP20, the CPU 40a determines a mode switching state by the mode switching switch 44, in other words, a mode selection state by the mode switching switch 44. This step functions as a switching determination unit described in each claim. If it is determined in step SP20 that the character input mode has been switched, the process proceeds to step SP30.

  In step SP30, the CPU 40a outputs a control signal to the LC oscillation circuit 41a or 41b, and causes the recording terminal 3 to generate a magnetic field having the frequency f1 or f2. Specifically, when the tip switch 42 is off, the CPU 40a outputs a control signal to the LC oscillation circuit 41a to cause the recording terminal 3 to generate a magnetic field having an approach frequency f1. When the tip switch 42 is on, the CPU 40a outputs a control signal to the LC oscillation circuit 41b to generate a magnetic field of the input frequency f2 for the recording terminal 3.

  Thereafter, in step SP40, the CPU 40a determines whether or not the mode has been switched by the user operating the mode switch 44. While the mode is not switched, that is, while the mode is the character input mode, the determination in step SP40 is not satisfied, and the process returns to step SP30 and the same procedure is repeated. That is, while the mode is the character input mode, the CPU 40a controls the LC oscillation circuit 41 so as to continuously generate the magnetic field of the frequency f1 or f2 to the recording terminal 3. On the other hand, when the mode is switched, the determination at step SP40 is satisfied, and the process returns to step SP20 to repeat the same procedure.

  By the way, if it is determined in step S20 that the state is switched to the keyword setting mode, the process proceeds to step SP50. In step SP50, the CPU 40a sets the mode variable PM representing the mode switching state to 0 representing the switching state to the keyword setting mode. Then, the process proceeds to step SP70.

  On the other hand, if it is determined in step S20 that the state is switched to the check / mark mode, the process proceeds to step SP60. In step SP60, the CPU 40a sets the mode variable PM to 1 representing the switching state to the check / mark mode. Thereafter, the process proceeds to step SP70.

  In step SP70, the CPU 40a outputs a control signal to the LC oscillation circuit 41c or 41d, and causes the recording terminal 3 to generate a magnetic field having the frequency f3 or f4 only during the generation time t1. Specifically, when the tip switch 42 is off, the CPU 40a outputs a control signal to the LC oscillation circuit 41c, and applies a magnetic field of the approach frequency f3 to the recording terminal 3 during the generation time t1. Only generate. When the tip switch 42 is on, the CPU 40a outputs a control signal to the LC oscillation circuit 41b, and causes the recording terminal 3 to generate a magnetic field of the input frequency f4 only during the generation time t1.

  Then, the process proceeds to step SP80, and the CPU 40a determines whether or not the value of the mode variable PM is 0 indicating the switching state to the keyword setting mode. If PM = 0, the determination at step SP80 is satisfied and the routine goes to step SP90. In step SP90, the CPU 40a resets the time Tc measured by the timer 40e of the microcomputer 40 to 0 and starts time counting. Thereafter, the process proceeds to step SP100. On the other hand, if PM = 1 in step SP80, the determination in step SP80 is not satisfied, and the process directly proceeds to step SP100.

  In step SP100, the CPU 40a determines whether the tip switch 42 has been turned on or off. Specifically, the CPU 40a contacts the writing surface 31 whether or not the tip switch 42 is switched from OFF to ON because the tip 2a that has been separated from the writing surface 31 contacts the writing surface 31. It is determined whether or not the tip switch 42 has been switched from on to off when the tip 2 a that has been separated from the writing surface 31. This substantially corresponds to detecting a change in contact of the tip 2a with the writing surface 31. That is, this step functions as a contact detection means described in each claim. When the tip switch 42 is turned on / off, that is, when a change in contact of the tip 2a is detected, the determination at step SP100 is satisfied, and the procedure returns to step SP70 and the same procedure is repeated. That is, while the mode is the keyword setting mode or the check mark mode, the CPU 40a generates the magnetic field of the frequency f3 or f4 at the timing when the change in the contact of the tip 2a is detected. 41 is controlled. On the other hand, if the tip switch 42 is not switched on / off, that is, if a change in contact of the tip 2a is not detected, the determination at step SP100 is not satisfied, and the routine goes to step SP110.

  In step SP110, the CPU 40a determines whether or not the mode of the electronic pen 2 has been switched by operating the mode switch 44 by the user. When the mode is switched, the determination at step SP110 is satisfied, and the process returns to step SP20 and the same procedure is repeated. On the other hand, if the mode has not been switched, the determination at step SP110 is not satisfied, and the routine goes to step SP120.

  In step SP120, the CPU 40a determines whether or not the value of the mode variable PM is 0 representing the switching state to the keyword setting mode. If PM = 1, the determination at step SP120 is not satisfied, and the routine returns to step SP100 and the same procedure is repeated. On the other hand, if PM = 0, the determination at step SP120 is satisfied, and the routine goes to step SP130.

  In step SP130, the CPU 40a determines whether or not the timing time tc that has started timing in step SP90 is delivered at the non-occurrence time t2. If tc = t2 is not satisfied, the determination at step SP130 is not satisfied, and the routine returns to step SP100 and the same procedure is repeated. On the other hand, if tc = t2, the determination at step SP130 is satisfied, and the routine returns to step SP70 and the same procedure is repeated. That is, while the mode is the keyword setting mode, the CPU 40a performs intermittent generation by alternately repeating the generation time t1 at which the magnetic field is generated at the frequency f3 or f4 and the non-generation time t2 at which the magnetic field is not generated. Thus, the LC oscillation circuit 41 is controlled. Note that this flow ends when, for example, the user turns off the electronic pen 2.

  As described above, the CPU 40a controls the LC oscillation circuit 41 so as to change the magnetic field generation interval depending on which of the keyword setting mode and the check / mark mode is selected by the mode changeover switch 44. That is, in the check mark mode, the LC oscillation circuit 41 generates a magnetic field at the writing start point and writing end point of the electronic pen 2. In the keyword setting mode, the LC oscillation circuit 41 generates a magnetic field at the predetermined interval and also at the writing start point and writing end point of the electronic pen 2.

  Next, the contents of the control processing performed by the CPU 80a of the microcomputer 80 of the recording terminal 3 in order to realize the functions as described above will be described with reference to FIG.

  In FIG. 12, this process is started when the user turns on the power of the recording terminal 3. First, the CPU 80a places the recording terminal 3 in a standby state in step SS10. That is, the CPU 80a outputs a control signal Sa (see FIG. 2) to the switch unit 90, the switch unit 90 connects the battery 21 and the approach detection circuit 50, and the battery 21, the position detection circuit 60, and the peripheral circuit 70. Shut off. As a result, the supply of power to the position detection circuit 60 and the peripheral circuit 70 is cut off, and power is supplied only to the approach detection circuit 50. As a result, the approach detection circuit 50 enters an operating state, and the position detection circuit 60 and the peripheral circuit 70 can be switched to a resting state. In the standby state, for example, a process with a large load such as a scan of the sense coil unit 110 started in step SS40 described later is not executed, so the microcomputer 80 itself is also switched to the sleep mode. These can save power.

Thereafter, the process proceeds to step SS20, and the CPU 80a determines whether or not the electronic pen 2 has approached the recording terminal 3. As described above, since the cancel signal S24 (see FIG. 2) is input when the electronic pen 2 approaches, the CPU 80a determines whether or not the cancel signal S24 from the continuation detection circuit 58 is input. If the release signal S24 is not input, the determination is not satisfied, and the process returns to step SS10 and the same procedure is repeated. When the electronic pen 2 approaches the recording terminal 3 and the release signal S24 is input, the determination in step SS20 is satisfied, and the process proceeds to step SS30. An interrupt function is used for the process of detecting the input of the release signal S24.

  In step SS30, the recording terminal 3 is set in an operating state. That is, the CPU 80a outputs a control signal Sa (see FIG. 2) to the switch unit 90, the switch unit 90 shuts off the battery 21 and the approach detection circuit 50, and the battery 21, the position detection circuit 60, and the peripheral circuit 70. Connect. As a result, the supply of power to the approach detection circuit 50 is interrupted, and power is supplied to the position detection circuit 60 and the peripheral circuit 70. As a result, the approach detection circuit 50 is switched to the resting state, and the position detecting circuit 60 and the peripheral circuit 70 that are in the resting state are switched to the operating state.

  In step SS40, the CPU 80a executes a scan process of the sense coil unit 110 provided in the coil sheets 100L and 100R. Specifically, the CPU 80a outputs, to the MUX 62, a coil selection signal S3 (see FIG. 2) for selecting the sense coils X1 to Xm and the sense coils Y1 to Yn in order with the cycle T described above. As described above, the magnetic field of the input frequency f2 or f4 generated from the LC oscillation circuit 41b or 41d with the tip switch 42 of the electronic pen 2 turned on, and any of the sense coils X1 to Xm and Y1 to Yn The signal S1 (see FIG. 2) is generated by magnetic induction. The signal S1 from the sense coils X1 to Xm and Y1 to Yn selected by the MUX 62 in a state where the signal S1 is generated is input to the MUX 62. The MUX 62 outputs a signal S11 corresponding to the input signal S1 to the amplifier circuit 64. The signal S11 is amplified by the amplifier circuit 64, and the amplified signal S12 (see FIG. 2) is input to the counter 80d of the microcomputer 80. The When step SS40 is completed in this way, the process proceeds to step SS50.

  In step SS50, the CPU 80a determines whether a signal S12 having an input frequency f2 or f4 equal to or higher than a predetermined threshold is detected for the counter 80d in step SS40. The signal S12 having the input frequency f2 is generated by the LC oscillation circuit 41b when the tip switch 42 is turned on when the user writes the character string CH on the writing surface 31 using the electronic pen 2 switched to the character input mode. It is a signal based on the magnetic induction generated by the magnetic field of the input frequency f <b> 2 and the sense coil unit 110. The signal S12 of the input frequency f4 is received by the tip switch 42 when the user describes the line segment UL or the check line Cs on the writing surface 31 using the electronic pen 2 switched to the keyword setting mode or the check mark mode. This is a signal based on the magnetic induction generated by the magnetic field generated by the sense coil unit 110 and the magnetic field of the input frequency f4 generated by the LC oscillation circuit 41d. While the counter 80d does not detect the signal S12 having the input frequency f2 or f4 equal to or higher than the threshold value, the determination in step SS50 is not satisfied, and the process proceeds to step SS55.

  In step SS55, the CPU 80a determines whether or not a predetermined time has elapsed since the determination in step SS50 was satisfied most recently from the present time. While the fixed time has not elapsed, the determination in step SS55 is not satisfied, and the process returns to step SS40 and the same procedure is repeated. If the predetermined time has elapsed, the determination at Step SS55 is satisfied, and the routine goes to Step SS60.

  In step SS60, the CPU 80a determines whether or not the recording terminal 3 is turned off. While the power is on, the determination in step SS60 is not satisfied, and the process returns to step SS10 and the same procedure is repeated. If the power is turned off, the determination at step SS60 is satisfied, and this flow ends.

  On the other hand, when the signal S12 having the input frequency f2 or f4 equal to or higher than the threshold value is detected by the counter 80d in step SS50, the determination in step SS50 is satisfied, and the process proceeds to step SS70.

  In Step SS70, the scan result of the sense coil unit 110 in Step SS40, that is, the magnetic field generated from the electronic pen 2 and having the input frequency f2 or f4 and any of the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110 is obtained. Calculation of the position of the electronic pen 2 based on the result of magnetic induction, that is, calculation of coordinate data is performed. Details of the calculation of the coordinate data will be described below in order.

(1) Position Coordinate Table As described above, the coordinate data is calculated using the position coordinate table stored in the ROM 80b of the microcomputer 80. The position coordinate table will be described with reference to FIGS. 13A to 13C and FIGS. 14A and 14B. In FIG. 13A, unlike FIG. 4, the sense coils X1 to X3 are indicated by solid lines. Further, in FIG. 14A, in order to make the arrangement of the sense coils X1 to X3 easy to understand, each side of the sense coils X1 to X3 is illustrated so as not to overlap.

  In FIG. 13A, the center lines of the three sense coils X1, X2, and X3 are C1, C2, and C3, respectively. The voltage values ex1, ex2, and ex3 generated in the sense coils X1, X2, and X3 are maximized at the centers C1 to C3 of the sense coils X1 to X3, respectively, as shown in FIG. At this time, as described above, the sense coils X1 to X3 are overlapped with one-half the width P1 in the x-axis direction so that their null points are outside the center of the adjacent sense coil. Yes.

  At this time, as shown in FIG. 13C, the voltage difference between the sense coils adjacent to each other of the sense coils X1 to X3 becomes the maximum value on the centers C1 to C3 of the sense coils X1 to X3. In addition, the voltage difference becomes a minimum value at an intermediate point between the center of the sense coils X1 to X3 and a portion where the adjacent sense coils X1 to X3 overlap each other. For example, in FIG. 13C, the right half of the graph of (ex1-ex2), that is, the portion indicated by the solid line, is the distance from the center C1 of the sense coil X1 to the intermediate point Q1 of the portion where the sense coil X2 is superimposed, That is, the behavior of ex1-ex2 is shown at a quarter of P1, which is a half of the overlapping pitch.

  Assuming that the electronic pen 2 exists at the intermediate point Q2, if (ex1-ex2) is detected, the distance ΔX1 from the center C1 to the intermediate point Q2 can be detected, and as a result, the x coordinate of the intermediate point Q2 is obtained. It is done. If the width P1 of the sense coils X1 to X3 is 50 mm, ΔX = P1 / 4 = 12.5 mm. Therefore, for example, when the solid line portion indicating the characteristic of (ex1-ex2) in FIG. 13C is converted into 8-bit digital data, the graph shown in FIG. 14A is obtained. By converting this graph into a table format, a position coordinate table shown in FIG. 14B is obtained.

(2) Coordinate determination using coil voltage value As described above, the signal S1 generated by magnetic induction between the magnetic field generated from the electronic pen 2 and the sense coils X1 to Xm, Y1 to Yn is amplified by the amplifier circuit 64. Then, the amplitude is detected by the rectifier circuit 66, and the signal S14 (see FIG. 2) is input to the microcomputer 80. The microcomputer 80 converts the input signal S14 into a digital signal corresponding to the amplitude, that is, the voltage value. The CPU 80a uses the voltage value represented by the digital signal to determine the coordinates of the electronic pen 2 using the position coordinate table described above. Hereinafter, the detailed procedure for determining the coordinates will be described taking the sense coils X1 to Xm as an example.

  First, the CPU 80a sequentially stores the voltage values e1 to em indicated by the digital signal converted from the signal S14 in the voltage value storage area of the RAM 80c in association with the coil numbers of the sense coils X1 to Xm.

  Thereafter, the CPU 80a selects the maximum voltage value emax among the voltage values e1 to em stored in the voltage value storage area in association with the coil numbers of the sense coils X1 to Xm. Then, the CPU 80a stores the coil number Xmax of the sense coils X1 to Xm that have generated the voltage value emax in the RAM 80c.

  Next, the CPU 80a determines the larger one of the voltage values e1 to em of the sense coils X1 to Xm adjacent to the sense coils X1 to Xm that have generated the voltage value emax. Then, the CPU 80a stores the coil numbers of the sense coils X1 to Xm that have generated the determined voltage values e1 to em as the coil number Xmax2 in the RAM 80c. For example, when the voltage value emax is generated by the sense coil X2, the CPU 80a compares the voltage value e1 of the adjacent sense coil X1 and the voltage value e3 of the sense coil X3, and calculates a large voltage value e1 or voltage value e3. decide. Then, the CPU 80a stores the coil number of the sense coil X1 that generated the determined voltage value e1 or the coil number of the sense coil X3 that generated the voltage value e3 in the RAM 80c as the coil number Xmax2.

  Thereafter, the CPU 80a compares the coil number max and the coil number max2 stored in the RAM 80c, and determines whether the coil number max2 is present in the + or − direction of the x axis from the coil number max. Note that the + direction of the x axis is the direction of the arrow indicating the x axis in FIG. 4, and the opposite direction to the − direction of the x axis. As a result of the determination, when the coil number Xmax2 is in the + direction with respect to the coil number Xmax, the CPU 80a sets the variable SIDE to 1. On the other hand, when the coil number Xmax2 is in the negative direction with respect to the coil number Xmax, the CPU 80a sets the variable SIDE to -1. For example, when the voltage value emax is generated by the sense coil X2, the coil number indicating the sense coil X2 is stored as the coil number Xmax in the RAM 80c, and the coil number of the sense coil X3 is stored as the coil number Xmax2, the CPU 80a Set variable SIDE to 1. On the other hand, when the voltage value emax is generated by the sense coil X2, the coil number indicating the sense coil X2 is stored as the coil number Xmax in the RAM 80c, and the coil number of the sense coil X1 is stored as the coil number Xmax2, the CPU 80a Set the variable SIDE to -1.

And CPU80a which set the variable SIDE calculates the variable DIFF by the following (Formula 1).
DIFF = e (max) −e (max2) (Formula 1)
The CPU 80a reads the position coordinate closest to the calculated DIFF from the position coordinate table (see FIG. 14B) stored in advance in the ROM 80b. Then, the CPU 80a sets the position coordinates read from the position coordinate table as a variable OFFSET.

Thereafter, the CPU 80a uses the variable SIDE and the variable OFFSET calculated as described above to obtain an x coordinate indicating the position of the electronic pen 2 in the x-axis direction according to the following (Equation 2).
X1 = (P1 / 2) × max + OFFSET × SIDE (Expression 2)
Here, (P1 / 2) × max indicates the x coordinate of the center of the coil number max.

  In the above description, the calculation of the x coordinate of the electronic pen 2 based on the signal S14 based on the magnetic induction in the sense coils X1 to Xm in the x axis direction has been described as an example. The y-coordinate of the electronic pen 2 is also calculated by a similar method using the signal S14 based on the magnetic induction in the sense coils Y1 to Yn.

  As described above, in step SS70, the coordinate data (xi, yi) of the electronic pen 2 is obtained, that is, calculated by the methods (1) and (2). Note that step SS40 and step SS70 function as position acquisition means described in each claim. After step SS70 is completed in this way, the process proceeds to step SS80.

  In Step SS80, the CPU 80a uses the magnetic field generated from the electronic pen 2 in Step SS40 and the magnetic induction between any of the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110 as a trigger. The frequency of the signal S12 (see FIG. 2) input to 80d is detected. This substantially corresponds to detecting the frequency of the magnetic field induced magnetically with the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110. That is, this step functions as the frequency detection means described in each claim.

  In step SS90, the CPU 80a determines whether the mode of the electronic pen 2 is the character input mode by comparing the frequency detected in step SS80 with the input frequency f2 or f4. This substantially corresponds to determining the mode of the electronic pen 2. That is, this step functions as a mode determination unit described in each claim. When the frequency detected in step SS80 is f2, the mode of the electronic pen 2 is regarded as the character input mode, the determination in step SS90 is satisfied, and the process proceeds to step SS100.

  In step SS100, the CPU 80a generates a pen position data string A using the coordinate data (xi, yi) of the electronic pen 2 calculated in step SS70. When the variable i representing the number of coordinate data is 0, that is, the first data, the coordinate data (xi, yi) calculated in step SS70 is set as the first data of the pen position data string A. When the variable i is not 0, the CPU 80a adds the coordinate data (xi, yi) calculated in step SS70 to the end of the already generated pen position data string A. Thereafter, the process proceeds to Step SS120 described later. By repeating this step, it is continuously performed in step SS70 based on reception of continuous writing signals in the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110, that is, magnetic induction with a magnetic field. Using the calculated plurality of coordinate data (xi, yi) for one stroke, a pen position data string A including the plurality of coordinate data (xi, yi) is generated. In this way, by generating the pen position data sequence A composed of a plurality of continuous coordinate data (xi, yi), as a result, the electronic pen 2 is a character corresponding to the character sequence CH described on the writing surface 31. The stroke data based on the row data, that is, the pen position data row A can be generated. That is, this step functions as character string data generating means described in each claim.

  On the other hand, in step SS90, when the frequency detected in step SS80 is f4, the electronic pen 2 is regarded as being in the keyword setting mode or the check mark mode, and the determination in step SS90 is not satisfied. Move on to SS110.

  In step SS110, the CPU 80a generates a pen position data string B different from the pen position data string A using the coordinate data (xi, yi) of the electronic pen 2 calculated in step SS70. If the variable i representing the number of coordinate data is 0, that is, the first data, the coordinate data (xi, yi) calculated in step SS70 is set as the first data in the pen position data sequence B. When the variable i is not 0, the CPU 80a adds the coordinate data (xi, yi) calculated in step SS70 to the end of the already generated pen position data string B. Thereafter, the process proceeds to step SS120. In addition, by repeating this step, one stroke discretely calculated in step SS70 based on the magnetic induction with the intermittent magnetic field in the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110. Using at least one coordinate data (xi, yi) of the minute, a pen position data sequence B including the at least one coordinate data (xi, yi) is generated.

  In step SS120, the CPU 80a determines whether a page turning operation has been performed by the user. That is, for example, when the description is completed from the upper left to the lower right on the left writing surface 31 of the notebook 30, the user starts the description on the right writing surface 31 which is the next page. In order for the recording terminal 3 to recognize this, page feed operation means (not shown) is provided at an appropriate location of the recording terminal 3. When the user shifts the description to the next page as described above, a corresponding operation signal is input to the microcomputer 80 by operating this page turning operation means. Based on this operation signal, the CPU 80a switches the page of the electronic file described above to the next page. Therefore, in this step SS120, the CPU 80a determines whether or not the user has operated the page feed operation means. When page switching of the electronic file is performed by appropriate automatic control instead of such page switching of the electronic file by the user's manual operation, in this step SS120, the CPU 80a performs the page switching by the automatic control. What is necessary is just to determine whether or not. While the page switching operation by the user is not performed, the determination in step SS120 is not satisfied, and the process returns to step SS40 and the same procedure is repeated. On the other hand, when the page switching operation is performed by the user, the determination at Step SS120 is satisfied, and the routine goes to Step SS130.

  In step SS130, the CPU 80a associates the pen position data string A generated in step SS110 with the pen position data string A generated in step SS100, that is, the pen position data string A and the pen for one page. The position data string B is synthesized and stored in the flash memory 72. Then, it returns to step SS40 and repeats the same procedure.

  Next, in order to realize the function of the keyword extracting method as described in FIGS. 8A to 8D and FIGS. 9A to 9D, the microcomputer 80 of the recording terminal 3 is used. The contents of the control process performed by the CPU 80a will be described with reference to FIG.

  In FIG. 15, this process is started when an external device is connected via, for example, the communication interface 74 and a predetermined application stored in the external terminal is activated. First, the CPU 80a determines whether or not the pen position data string B is stored in the flash memory 72 in step SS200. If the pen position data string B is not stored, the determination in step SS200 is not satisfied, and this flow ends. On the other hand, if the pen position data sequence B has been stored, the determination at Step SS200 is satisfied, and the routine goes to Step SS210.

  In step SS210, the CPU 80a uses the discrete coordinate data (xi, yi) included in the pen position data string B stored in the flash memory 72, and the electronic pen 2 uses a character string other than the character string described on the writing surface 31. Data, line data corresponding to the line UL in this example, that is, stroke data based on the pen position data string B is generated.

  Thereafter, in step SS220, the CPU 80a displays the line segment represented on the electronic file by the line segment data generated in step SS210 out of the character string data based on the pen position data string A stored in the flash memory 72. Character string data corresponding to the character string CHi on the electronic file included in the predetermined range of ULj is extracted as a keyword. Specifically, as described with reference to FIGS. 8A to 8D and FIGS. 9A to 9D, characters from di <Hi and Wi> Li / 2 are used. Character string data corresponding to the character string is extracted as a keyword. This step functions as character string data extraction means described in each claim.

  In step SS230, the CPU 80a recognizes the character string data extracted as a keyword in step SS220 using a known appropriate technique. Then, the character string recognized as a character is associated with the image data as a management tag and stored in the flash memory 72. Thereafter, this flow is terminated.

  Next, in order to realize the function of selecting the check box Cb selected on the writing surface 31 as described with reference to FIGS. 10A to 10C, the CPU 80a of the microcomputer 80 of the recording terminal 3 uses the CPU 80a. The contents of the control processing to be performed will be described with reference to FIG.

  In FIG. 16, this processing is started when an external device is connected via the communication interface 74 and a predetermined application stored in the external terminal is started. First, the CPU 80a determines whether the pen position data string B is stored in the flash memory 72 in step SS300. If the pen position data string B is not stored, the determination in step SS300 is not satisfied, and this flow ends. On the other hand, if the pen position data sequence B has been stored, the determination at Step SS300 is satisfied, and the routine goes to Step SS310.

  In step SS310, the CPU 80a uses the discrete coordinate data (xi, yi) included in the pen position data string B stored in the flash memory 72, so that the electronic pen 2 has a character string other than the character string described on the writing surface 31. Data, that is, check line data corresponding to the check line Cs in this example, that is, stroke data based on the pen position data string B is generated.

Thereafter, in step SS320, the CPU 80a checks that the line segment data generated in step SS210 is the closest to the line segment Lj represented on the electronic file among the plurality of check boxes Cb on the electronic file. The box Cb is selected as the check box Cb selected on the writing surface 31.
Specifically, as described with reference to FIG. 10C, for each check box Cb on the electronic file, the minimum distance dm between the line segment Lj and the center point cp of the check box Cb on the electronic file is set. calculate. Then, the check box Cb having the smallest calculated minimum distance dm is selected as the check box Cb selected on the writing surface 31. Thereafter, this flow is terminated.

  In the above, step SS210 shown in FIG. 15 and step SS310 shown in FIG. 16 function as the non-character string data generation means described in each claim, and step S210 also functions as the line segment data generation means. To do.

  As described above, in the present embodiment, when the user writes in a predetermined manner on the writing surface 31 of the notebook 30, or when writing characters in the above example, the user switches the mode change switch of the electronic pen 2. 44 to switch to the character input mode. The state of switching to the character input mode is determined in step SP20 of FIG. 11, and the LC oscillation circuit 41 continuously generates the magnetic field to the recording terminal 3 based on the control of the microcomputer 40. The recording terminal 3 detects the position of the electronic pen 2 by a magnetic field continuously generated from the electronic pen 2, and recognizes the character written on the writing surface 31 by the user based on the movement locus of the electronic pen 2.

  On the other hand, when the user describes symbols on the writing surface 31 in a manner different from the character input mode, and when performing descriptions other than characters in the above example, the user presses the mode changeover switch 44 of the electronic pen 2. Use to switch to keyword setting mode or check mark mode. The switching state to the keyword setting mode or the check mark mode is determined in step SP20 of FIG. 11, and based on the control of the microcomputer 40, the LC oscillation circuit 41 generates a magnetic field in the character input mode to the recording terminal 3. It occurs intermittently at intervals longer than the interval. As described above, the recording terminal 3 detects the position of the electronic pen 2 by the magnetic field generated intermittently from the electronic pen 2 and recognizes the content written on the writing surface 31.

  As described above, in the present embodiment, the electronic pen 2 generates a magnetic field by properly using the character input mode and the keyword setting mode or the check / mark mode with different magnetic field generation intervals. Thus, in the keyword setting mode and the check mark mode in which the magnetic field is intermittently generated at intervals longer than the magnetic field generation interval in the character input mode, in the case of inputting a symbol, in the above example, when inputting other than a character, The power consumed by the electronic pen 2 can be reduced. As a result, energy saving can be achieved.

  Here, in general, in an electronic pen having a character input function and a function other than character input, if the detection accuracy on the recording terminal side is lowered in the case of character input, there is a high possibility of causing a practical problem. However, in the case of input other than characters, there are many cases where there is no practical problem even if the detection accuracy on the recording terminal side is lowered compared to the case of character input. Therefore, in the present embodiment, in particular, the electronic pen 2 has a character input mode corresponding to a case where characters are written on the writing surface 31, and a keyword setting mode and a check mark corresponding to a case where characters other than characters are written on the writing surface 31. Mode.

  In the character input mode, the LC oscillation circuit 41 continuously generates a magnetic field having the frequency f1 or f2 to the recording terminal 3. The continuously generated magnetic field is magnetically induced by the sense coil unit 110 of the recording terminal 3. And the frequency of the said magnetic field is detected and it determines with the mode of the electronic pen 2 being character input mode. In this case, a plurality of coordinate data of the electronic pen 2 is continuously calculated on the recording terminal 3 side by the user's writing operation. Based on the plurality of coordinate data, character string data corresponding to the character string CH written on the writing surface 31 is generated. Thereby, the recording terminal 3 can recognize the character described on the writing surface 31 by the user.

  On the other hand, in the keyword setting mode or the check mark mode, the LC oscillation circuit 41 intermittently generates a magnetic field of the frequency f3 or f4 to the recording terminal 3 based on the control of the microcomputer 40. A magnetic field generated intermittently at an interval longer than the magnetic field generation interval in the character input mode is magnetically induced by the sense coil unit 110 of the recording terminal 3 as described above. Then, the frequency of the magnetic field is detected, and it is determined that the mode of the electronic pen 2 is the keyword setting mode or the check mark mode. In this case, at least one coordinate data of the electronic pen 2 is discretely calculated on the recording terminal 3 side by the user's writing operation. Then, based on the at least one coordinate data, data other than the character string corresponding to the character string described on the writing surface 31 is generated. Thereby, the recording terminal 3 can recognize the description content on the writing surface 31.

  As described above, in the keyword setting mode or the check mark mode, the electronic pen 2 intermittently performs generation of the magnetic field of the frequency f3 or f4 by temporally decimating the magnetic field generation interval in the character input mode. Thereby, the power consumed by the electronic pen 2 when inputting characters other than characters can be reduced and energy saving can be achieved without reducing the character recognition accuracy on the recording terminal 3 side when inputting characters.

  In the present embodiment, in particular, in step SP100 of FIG. 11 described above, a change in contact of the tip 2a of the electronic pen 2 with the writing surface 31 is detected. When a change in contact of the tip 2a is detected, the LC oscillation circuit 41 generates a magnetic field to the recording terminal 3 at the detected timing.

  Thereby, since the magnetic field corresponding to the description on the writing surface 31 can be reliably generated in the recording terminal 3, the recording terminal 3 can perform reliable detection without leakage.

  In this embodiment, in particular, the electronic pen 2 has a keyword setting mode and a check / mark mode. The mode changeover switch 44 changes the magnetic field generation interval depending on which of the keyword setting mode and the check / mark mode is selected.

Thereby, when the user selects the keyword setting mode or the check mark mode and the description other than characters is performed, the fine magnetic field generation control is performed according to the use, and the power consumption of the electronic pen 2 is reduced. Can be achieved. As a result, energy saving can be achieved more reliably.

  In the present embodiment, particularly, the LC oscillation circuit 41 of the electronic pen 2 generates a magnetic field having the frequency f3 or f4 for a generation time t2 longer than the scan period T in the recording terminal 3. Thereby, while the electronic pen 2 is generating the magnetic field of the frequency f3 or f4, on the recording terminal 3 side, the sense coils X1 to Xm and Y1 to Yn of the sense coil unit 110 performing magnetic induction with the magnetic field. Is selected at least once, the signal S14 (see FIG. 2) resulting from the magnetic field is reliably acquired by the microcomputer 80.

  In the present embodiment, in particular, when the user selects a keyword setting mode on the electronic pen 2 and performs input other than characters, at least one of the electronic pens 2 calculated discretely on the recording terminal 3 side. Based on the coordinate data, line segment data corresponding to the line segment UL written on the writing surface 31 is generated. When line segment data is generated in response to the user's selection of the keyword setting mode in this way, the character string corresponding to the character string CHi included in the predetermined range of the line segment ULj on the electronic file. Data is extracted.

  Thereby, after the user selects the character input mode and writes the character string CH on the writing surface 31, the user selects the keyword setting mode and writes the line segment UL in the vicinity of the written character string CH. The character string data corresponding to the character string CH is extracted as a keyword. Therefore, this keyword can be used as a management tag for a file containing character string data.

  Further, when it is desired to describe a line segment in the vicinity of the character string CH without being extracted as a keyword as described above, the user may describe the line segment while the character input mode is still selected. Therefore, the user simply describes the case where a line segment is written near the character string CH as a visual effect and the case where the line segment UL is written near the character string CH for extraction as a keyword. The mode selection switch 44 can select the mode properly. As a result, it is possible to perform appropriate keyword extraction in accordance with the user's intention, and high convenience can be obtained.

  Note that the voltage of the battery 43 of the electronic pen 2 may be detected, and the LC oscillation circuit 41 may be controlled so that the microcomputer 40 changes the magnetic field generation interval according to the detected voltage value. . As a result, when the user selects the keyword setting mode or the check mark mode and the description other than the characters is performed, the generation of fine magnetic fields is controlled according to the remaining battery level to reduce power consumption. Can do. As a result, energy saving can be achieved more reliably.

  When the mode of the electronic pen 2 is the keyword setting mode or the check mark mode, the position of the electronic pen 2 may be calculated with low accuracy on the recording terminal 3 side. Alternatively, when the mode of the electronic pen 2 is the keyword setting mode or the check mark mode, the scanning speed of the sense coil unit 110 may be increased.

  In the above description, the coordinate data of the electronic pen 2 is acquired by the non-contact method in which the sense coil unit 110 of the recording terminal 3 transmits and receives electromagnetic waves to and from the electronic pen 2. However, the present invention is not limited thereto. That is, the coordinate data of the pen is acquired by a contact method in which the movement of the pen is detected by the tablet sheet when a desired character string is written on the tablet sheet using the pen, for example. May be.

  In addition, in the above, the arrow shown in FIG. 2 shows an example of a signal flow, and does not limit the signal flow direction.

  Further, the flowcharts shown in FIGS. 11, 12, 15 and 16 are not intended to limit the present invention to the procedures shown in the above-mentioned flow, but to add procedures within the scope not departing from the spirit and technical idea of the invention. You may delete or change the order.

  In addition to those already described above, the methods according to the above-described embodiments and modifications may be used in appropriate combination.

  In addition, although not illustrated one by one, the present invention is implemented with various modifications within a range not departing from the gist thereof.

1 Electronic Writing System 2 Electronic Pen (Electronic Writing Tool)
2a tip 3 recording terminal 30 notebook (written body)
31 Writing surface 40 Microcomputer (transmission control means)
41, 41a-d LC oscillation circuit (signal transmission means)
42 Tip switch 44 Mode selector switch (operating means)
62 MUX (switching connection means)
80 Microcomputer (calculation means)
X1-Xm, Y1-Yn Sense coil (coil)

Claims (7)

An electronic writing instrument for performing data input corresponding to the writing content to the writing body on a recording terminal provided on the writing body,
Signal transmitting means for generating and transmitting a writing signal for position detection of the electronic writing instrument to the recording terminal;
A first mode corresponding to when describing the character in a predetermined manner to the object to be cursive, wherein the first mode a different embodiment, corresponding to the case of the description of the symbols other than letters said to be cursive The second mode can be switched between the operating means,
Switching determination means for determining a mode switching state between the first mode and the second mode by the operating means;
When it is determined by the switching determination means that the state is switched to the first mode , a predetermined interval is used with the first writing signal corresponding to the first mode as a first transmission level parameter for the recording terminal. Or is transmitted with a predetermined output, and when it is determined by the switching determination means that the state is switched to the second mode, the recording terminal is different from the first writing signal. A transmission level parameter, the second writing signal corresponding to the second mode is transmitted as a second transmission level parameter at an interval longer than the transmission interval of the first writing signal in the first mode, or Transmission control means for controlling the signal transmission means to transmit at a lower output than the transmission output of the first writing signal in the first mode ;
An electronic writing instrument comprising: Having contact detection means for detecting a change in contact of the tip with respect to the writing object;
The transmission control means includes
The signal transmission unit is controlled to transmit the writing signal to the recording terminal at the detected timing when a change in contact of the tip is detected by the contact detection unit. The electronic writing instrument according to 1 . As the second mode,
It has a plurality of modes according to the description content to the cursive,
The operation means includes
One of the plurality of modes included in the second mode can be selected,
The switching determination means includes
The selection state of the mode by the operation means can be determined,
The transmission control means includes
Depending on which of the plurality of modes is selected by the operating means, so as to vary the transmission interval, claim 1 or claim 2 electronic writing instrument wherein the controller controls the signal transmitter. A recording terminal provided on the cursive body,
For the recording terminal, an electronic writing instrument for performing data input corresponding to the writing content to the writing body,
An electronic writing system comprising:
The electronic writing instrument is:
Signal transmitting means for generating and transmitting a writing signal for position detection of the electronic writing instrument to the recording terminal;
A first mode corresponding to when describing the character in a predetermined manner to the object to be cursive, wherein the first mode a different embodiment, corresponding to the case of the description of the symbols other than letters said to be cursive The second mode can be switched between the operating means,
Switching determination means for determining a mode switching state between the first mode and the second mode by the operating means;
When it is determined by the switching determination means that the state is switched to the first mode , a predetermined interval is used with the first writing signal corresponding to the first mode as a first transmission level parameter for the recording terminal. Or is transmitted with a predetermined output, and when it is determined by the switching determination means that the state is switched to the second mode, the recording terminal is different from the first writing signal. A transmission level parameter, the second writing signal corresponding to the second mode is transmitted as a second transmission level parameter at an interval longer than the transmission interval of the first writing signal in the first mode, or Transmission control means for controlling the signal transmission means to transmit at a lower output than the transmission output of the first writing signal in the first mode ;
Have
The recording terminal
A plurality of coils capable of receiving the writing signal transmitted from the signal transmitting means;
Based on the reception result of the writing signal in the plurality of coils, a calculation means for performing a predetermined calculation related to the position information of the electronic writing instrument;
Switching connection means for sequentially switching and connecting the calculation means to each coil every predetermined period;
An electronic writing system characterized by comprising: The computing means of the recording terminal is
Position acquisition means for acquiring position information of the electronic writing instrument based on the reception result of the writing signal in the plurality of coils;
Frequency detection means for detecting the frequency of the writing signal received by the plurality of coils;
Mode determining means for determining the mode of the electronic writing instrument based on the frequency detected by the frequency detecting means;
The plurality of pieces of position information acquired by the position acquisition unit based on reception of the first writing signal by the plurality of coils when the mode determination unit determines that the electronic writing instrument is in the first mode. Character string data generating means for generating character string data corresponding to the character string described in the writing object by the electronic writing instrument,
At least one position acquired by the position acquisition unit based on reception of the second writing signal by the plurality of coils when the mode determination unit determines that the electronic writing instrument is in the second mode. Using information, the electronic writing instrument generates non-character string data generating means for generating data other than the character string described in the cursive body,
The electronic writing system according to claim 4, further comprising: The transmission control means of the electronic writing instrument is:
When it is determined by the switching determination means that the state is switched to the first mode, the first writing signal is continuously transmitted, and the switching determination means is a state of switching to the second mode. If it is determined, the signal transmission means is controlled to transmit the second writing signal intermittently and with a transmission time longer than the period,
The character string data generating means of the recording terminal is
Using the plurality of position information continuously acquired by the position acquisition means based on the continuous reception of the first writing signal by the plurality of coils, the character string data is generated,
The non-character string data generating means includes
Generating data other than the character string using the at least one position information discretely acquired by the position acquisition unit based on the intermittent reception of the second writing signal by the plurality of coils. The electronic writing system according to claim 5 . The non-character string data generating means includes
When it is determined that the electronic writing instrument is in the second mode by the mode determination unit, the electronic writing instrument is used for the object by using the at least one position information discretely acquired by the position acquisition unit. It has line segment data generation means for generating line segment data corresponding to the line segment written in cursive,
The computing means is
Of the character string data generated by the character string data generating means, the character string included in a predetermined range of the line segment represented by the line segment data generated by the line segment data generating means. 7. The electronic writing system according to claim 6 , further comprising character string data extracting means for extracting corresponding character string data.

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