Active pen and position detection system

Abstract

Provided are an active pen and a position detection system capable of executing a variety of functions corresponding to the state of the remaining power of the active pen. The active pen (12) is provided with a control means (40) for controlling the operation of the reception circuit (46), the transmission circuit (48), or the accessory function unit (50) in a plurality of operation modes including a normal mode and a low-consumption mode. The low-consumption mode is an operation mode in which the frequency of execution of a specific drive operation relating to at least one of reception of an uplink signal (US), transmission of a downlink signal (DS), and an accompanying function is relatively low or the amount of execution of the specific drive operation is relatively small.

Description

Technical Field

[0001] The invention relates to an active pen and a position detection system. Background Art

[0002] Conventionally, there is known a position detection system consisting of an active electronic pen (hereinafter referred to as an "active pen"), which is a position indicator with a built-in power source, and an electronic device including a touch sensor. In such a system, signals are sent and received between the active pen and the electronic device in order to exchange data or synchronize control (for example, refer to Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 6473554 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, if the user continues to use the active pen when the remaining power is low, there is a problem that the active pen cannot perform a desired operation due to insufficient power.

[0008] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an active pen and a position detection system capable of executing various functions according to the remaining power status of the active pen.

[0009] Means for solving problems

[0010] The active pen in the first scheme of the present invention is a pen used together with an electronic device configured to include an electrostatic capacitance touch sensor in which a plurality of sensor electrodes are arranged in a planar shape, wherein the active pen comprises: a receiving circuit for receiving an uplink signal from the electronic device; a transmitting circuit for transmitting a downlink signal to the electronic device; an additional function unit for performing an additional function different from the reception of the uplink signal and the transmission of the downlink signal; and a control unit for controlling the operation of the receiving circuit, the transmitting circuit or the additional function unit according to a plurality of operation modes including a normal mode and a low consumption mode, wherein the normal mode is an operation mode in which the execution frequency of a specific drive action related to at least one of the reception of the uplink signal, the transmission of the downlink signal and the additional function is relatively high or the execution amount of the specific drive action is relatively large, and the low consumption mode is an operation mode in which the execution frequency of the specific drive action is relatively low or the execution amount of the specific drive action is relatively small.

[0011] The position detection system in the second scheme of the present invention comprises: an electronic device, which is configured to include a capacitive touch sensor in which multiple sensor electrodes are arranged in a planar shape; and an active pen, which is used together with the electronic device, and the active pen comprises: a pen-side receiving circuit, which receives an uplink signal from the electronic device; a pen-side transmitting circuit, which transmits a downlink signal corresponding to the uplink signal to the electronic device; and a pen-side control unit, which controls the driving action of the pen-side receiving circuit or the pen-side transmitting circuit according to a plurality of action modes including a normal mode and a low-consumption mode, the normal mode being an action mode in which the downlink signal is continuously transmitted, and the low-consumption mode being an action mode for stopping the transmission of the downlink signal and allowing the active pen to function as a passive indicator.

[0012] A position detection system in a third aspect of the present invention comprises: an electronic device configured to include a capacitive touch sensor in which a plurality of sensor electrodes are arranged in a planar shape; an active pen for use with the electronic device; and a reporting unit provided in the electronic device or the active pen and reporting to a user explicitly or implicitly that the remaining power of the active pen is low, wherein the active pen comprises: a receiving circuit for receiving an uplink signal from the electronic device; a transmitting circuit for transmitting a downlink signal to the electronic device; an additional function unit for performing an additional function different from the reception of the uplink signal and the transmission of the downlink signal; and a control unit for controlling the operation of the receiving circuit, the transmitting circuit or the additional function unit according to a plurality of operation modes including a normal mode and a low-power mode, wherein the execution frequency of a specific drive operation related to at least one of the reception of the uplink signal, the transmission of the downlink signal and the additional function is relatively high or the execution amount of the specific drive operation is relatively large, and the low-power mode is an operation mode in which the execution frequency of the specific drive operation is relatively low or the execution amount of the specific drive operation is relatively small.

[0013] Effects of the Invention

[0014] According to the present invention, various functions can be executed according to the remaining power status of the active pen. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a diagram showing the overall configuration of a position detection system common to each embodiment of the present invention.

[0016] Figure 2 yes Figure 1 An exploded perspective view of the active pen shown.

[0017] Figure 3This is a block diagram of the pen-side controller included in the active pen in the first embodiment.

[0018] Figure 4 is with Figure 3 The functional block diagram related to the pen-side MCU is shown.

[0019] Figure 5 It is shown Figure 3 and Figure 4 A flowchart of an example of a mode switching action of the pen-side controller.

[0020] Figure 6 : is a diagram schematically showing a first common method of mode flags.

[0021] Figure 7 is a diagram schematically showing a second common method of mode flags.

[0022] Figure 8 This is a diagram showing an example of the selection result of the operation mode.

[0023] Fig. 9 This is a diagram schematically showing the differences in driving operations between the operation modes in the first embodiment.

[0024] Fig.10 This is a diagram showing an example of the internal structure of the electronic device according to the second embodiment.

[0025] Fig.11 is with Fig.10 The functional block diagram related to the sensor side controller is shown.

[0026] Fig.12 It is shown Fig.10 and Fig.11 A flowchart of an example of a mode switching action of a sensor side controller.

[0027] Fig.13 This is a diagram schematically showing a first difference in the driving operation between the operation modes in the second embodiment.

[0028] Fig.14 1 is a diagram schematically showing a second difference in the driving operation between the operation modes in the second embodiment.

[0029] Fig.15 This is a first block diagram of the pen-side controller included in the active pen in the second embodiment.

[0030] Fig.16 A diagram showing an example of a signal waveform of a downlink signal.

[0031] Fig.171 is a diagram showing a main part of a circuit configuration for realizing analog activation.

[0032] Fig.18 This is a second block diagram of the pen-side controller included in the active pen in the second embodiment.

[0033] Fig.19 It is a schematic configuration diagram of a position detection system in a third embodiment.

[0034] Fig. 20 It is shown Fig.19 A diagram showing an example of a method of displaying the position of an active pen.

[0035] Fig.21 This is a diagram showing an example of a method of changing the display form of the cursor. DETAILED DESCRIPTION

[0036] Regarding the active pen and position detection system of the present invention, Figure 1 It should be noted that the present invention is not limited to the various embodiments and variations described below, and can of course be freely changed within the scope of the main purpose of the present invention. Alternatively, the various structures can be arbitrarily combined within the scope that does not cause technical contradictions. Alternatively, the execution order of the various steps constituting the flowchart can be changed within the scope that does not cause technical contradictions.

[0037] [Description of Position Detection System 10]

[0038] <Overall Structure>

[0039] Figure 1 This is a diagram showing the overall configuration of a position detection system 10 that is common to each embodiment of the present invention. The position detection system 10 is basically composed of an active pen 12 and an electronic device 14 used together with the active pen 12 .

[0040] The active pen 12 is a pen-shaped pointing device, and is configured to be able to communicate unidirectionally or bidirectionally with the electronic device 14. In this embodiment, the active pen 12 is an "active type" stylus pen that actively generates a signal using its own stored electrical energy and sends the signal as a downlink signal DS to the electronic device 14. In the case of an active electrostatic coupling method (AES) or an electrostatic capacitance method, the active pen 12 and the electronic device 14 are electrostatically coupled to each other through a capacitor Cpen.

[0041] The electronic device 14 is a computer owned by the user, and is composed of, for example, a tablet terminal with or without a display function, a smart phone, a personal computer, etc. Specifically, the electronic device 14 is configured to include a host processor, a memory, a communication module, or a display panel (none of which is shown) in addition to the touch sensor 16 and the sensor-side controller 18. The host processor uses the position data sequentially output from the sensor-side controller 18 to perform digital ink generation processing, pointer display processing, etc.

[0042] The touch sensor 16 is, for example, a capacitive sensor (more specifically, a mutual capacitance sensor or a self-capacitive sensor) in which a plurality of sensor electrodes are arranged in a planar shape. Each sensor electrode may be formed of a transparent conductive material including ITO (Indium Tin Oxide), or may be formed of a wire mesh sensor. The touch sensor 16 may be a "built-in" sensor (if further classified, an On-Cell or In-Cell) that is integrally formed with a display panel not shown, or may be an "external" sensor (or an Out-Cell) that is mounted from the outside to the display panel.

[0043] The sensor-side controller 18 is a control circuit connected to the touch sensor 16 and used to control communication with the active pen 12 via the touch sensor 16. Specifically, the sensor-side controller 18 sends an uplink signal US to the active pen 12, receives a downlink signal DS from the active pen 12, and detects the indicated position of the active pen 12.

[0044] <Device Structure of Active Pen 12>

[0045] Figure 2 yes Figure 1 The active pen 12 is an exploded perspective view of the active pen 12. The active pen 12 is composed of a core 20, a tip electrode 22 (equivalent to a "pen electrode"), a ring electrode 24 (equivalent to a "pen electrode"), a pen pressure sensor 26, a pen-side controller 28, a power module 30 (equivalent to a "power supply"), and a housing 32.

[0046] The core 20 is a rod-shaped member arranged along the pen shaft of the active pen 12. The tip electrode 22 and the ring electrode 24 are respectively made of or contain a conductive material such as metal. Specifically, the tip electrode 22 is a conical electrode mounted on the front end of the core 20. In addition, the ring electrode 24 is a conical ring-shaped electrode whose diameter gradually decreases as it goes to the front end side.

[0047] The pen pressure sensor 26 is physically connected to the core 20 and is configured to detect the amount of pen pressure applied to the front end side (that is, the pen tip) of the core 20. As a detection method of the pen pressure sensor 26, for example, an electrostatic capacitance method, a film resistance method, a piezoelectric element method, an optical method, or a MEMS (Micro Electro-Mechanical System) method is used.

[0048] The pen-side controller 28 is composed of a single or multiple substrates constituting a circuit for operating the active pen 12. The power module 30 is composed of, for example, a battery or a capacitor, and supplies driving power to the electronic components or elements on the pen-side controller 28. The housing 32 is configured to accommodate the above-mentioned components.

[0049] [First embodiment]

[0050] First, regarding the position detection system 10A in the first embodiment, Figure 3~Figure 9 The position detection system 10A is equivalent to Figure 1 This is one embodiment of the position detection system 10 shown. This position detection system 10A is configured to include an active pen 12A and an electronic device 14A.

[0051] <Block Diagram of Pen-Side Controller 28a>

[0052] Figure 3 1 is a block diagram of the pen-side controller 28a of the active pen 12A in the first embodiment. The pen-side controller 28a includes a microcontroller unit (hereinafter referred to as "pen-side MCU 40"), a first switch 42, a second switch 44, a pen-side receiving circuit 46, a pen-side transmitting circuit 48, and an additional function unit 50.

[0053] The pen-side MCU 40 (equivalent to the "pen-side control unit") is a unit that performs overall control of various parts of the active pen 12A. The pen-side MCU 40 is configured to receive an uplink signal US from the electronic device 14A by performing desired reception control on the pen-side receiving circuit 46. The pen-side MCU 40 is configured to transmit a downlink signal DS to the electronic device 14A by performing desired digital signal processing on the data supplied from the pen-side receiving circuit 46 and performing desired transmission control on the pen-side transmitting circuit 48.

[0054] The first switch 42 is a switch element configured to connect a common terminal to either an R terminal or a T terminal. The common terminal of the first switch 42 is connected to the tip electrode 22, the R terminal is connected to the input end of the pen-side receiving circuit 46, and the T terminal is connected to the output end of the pen-side transmitting circuit 48. The first switch 42 is supplied with a first switch control signal SWC1 by the pen-side MCU 40 to perform switch control, and selectively receives the uplink signal US and transmits the downlink signal DS.

[0055] The second switch 44 is a switch element configured to connect a common terminal to either an R terminal or a T terminal. The common terminal of the second switch 44 is connected to the ring electrode 24, the R terminal is connected to the input end of the pen-side receiving circuit 46, and the T terminal is connected to the output end of the pen-side transmitting circuit 48. The pen-side MCU 40 supplies a second switch control signal SWC2 to the second switch 44 to perform switch control, and selectively performs reception of the uplink signal US and transmission of the downlink signal DS.

[0056] The pen-side receiving circuit 46 is a circuit that demodulates the uplink signal US sensed by the tip electrode 22 or the ring electrode 24 and outputs the demodulated data to the pen-side MCU 40. The ground terminal of the pen-side receiving circuit 46 is grounded to the housing 32 of the active pen 12A. Specifically, the pen-side receiving circuit 46 includes a waveform regenerator 52 and a correlation operator 54.

[0057] The waveform regenerator 52 binarizes the voltage level induced at the tip electrode 22 or the ring electrode 24 using a clock of a predetermined rate, shapes it into a binary string of positive and negative polarity values ​​(that is, a chip string), and outputs it. The clock frequency is set to, for example, an integral multiple of the chip rate of the spread spectrum code.

[0058] The correlation calculator 54 stores the chip string from the waveform regenerator 52 in a register, and performs correlation calculation with the spreading code while sequentially shifting the chip string using a clock. As a result, the chip string included in the uplink signal US is decoded.

[0059] The pen-side transmission circuit 48 is a circuit that generates a downlink signal DS according to the control of the pen-side MCU 40. When the downlink signal DS is a "position signal", the pen-side transmission circuit 48 outputs the carrier signal in a non-modulated manner, and when the downlink signal DS is a "data signal", the carrier signal is modulated using transmission data and output. Specifically, the pen-side transmission circuit 48 includes a modulator 56 and a boost circuit 58.

[0060] The modulator 56 generates a carrier signal such as a rectangular wave or a triangular wave, and outputs it in a modulated state or as it is based on the control of the pen-side MCU 40. When sending a burst signal, the modulator 56 outputs the carrier signal as it is without modulation according to the instruction of the pen-side MCU 40. On the other hand, when sending a data signal, the modulator 56 modulates the carrier signal (OOK, PSK, etc.) using the data supplied from the pen-side MCU 40, and outputs the modulated signal obtained as a result.

[0061] The booster circuit 58 generates a downlink signal DS by boosting the output signal supplied from the modulator 56 to a certain amplitude. The downlink signal DS generated by the booster circuit 58 is sent to the outside from the tip electrode 22 via the first switch 42 or from the ring electrode 24 via the second switch 44 .

[0062] The additional function unit 50 is configured to be able to perform a function (hereinafter referred to as an "additional function") that is different from the reception of the uplink signal US or the transmission of the downlink signal DS and is additional to the basic function related to the pen input. The additional function unit 50 may be a part of the structure of the pen-side controller 28a, or may replace it or be a structure independent of the pen-side controller 28a at the same time.

[0063] <Functional Block Diagram>

[0064] Figure 4 is with Figure 3 The pen-side MCU 40 is a functional block diagram of the pen-side MCU 40. The pen-side MCU 40 includes a mode switching unit 60, an action control unit 62, a data writing unit 64, and a data storage unit 66 (equivalent to a "memory"). In addition, in addition to the pen pressure sensor 26 ( Figure 2 )、pen side receiving circuit 46 and pen side sending circuit 48 ( Figure 3 ), a communication chip 72, a pen switch 74, a vibration device 76, and a power management integrated circuit (hereinafter referred to as "PMIC78") are also connected. Here, the pen pressure sensor 26, the communication chip 72, the pen switch 74, the vibration device 76, and the data writing unit 64 are equivalent to the additional function unit 50 that performs various additional functions.

[0065] The mode switching unit 60 switches and executes a plurality of operation modes using mode information including a mode flag. The types of operation modes are classified into, for example, [1] a "first operation mode group" switched according to the detection result of the active pen 12A or the passive pointer, or [2] a "second operation mode group" switched according to the remaining power of the power supply provided in the active pen 12A.

[0066] The first action mode group includes, for example, [1] an "STP (Simultaneous Pen Touch) mode" in which the positions of the active pen 12A and the passive pointer are detected by time division, or [2] an "exclusive mode" in which the detection of the passive pointer is temporarily stopped and only the position of the active pen 12A is detected.

[0067] In the second action mode group, a normal mode or a low consumption mode is included. Here, the "normal mode" means an action mode that consumes relatively more power accompanied by at least one of the driving actions (hereinafter referred to as "specific driving actions") related to the reception of the uplink signal US, the transmission of the downlink signal DS and the incidental functions. In addition, the "low consumption mode" means an action mode that consumes relatively less power accompanied by a specific driving action. For example, in the "normal mode", the execution frequency of a specific driving action can be made relatively high or the execution amount of a specific driving action can be made relatively large. In addition, in the "low consumption mode", the execution frequency of a specific driving action can be made relatively low or the execution amount of a specific driving action can be made relatively small.

[0068] The mode switching unit 60 can detect the operation mode of the electronic device 14A based on the uplink signal US received via the pen-side receiving circuit 46, and switch the operation mode of the active pen 12A according to the detection result. For example, when the mode switching unit 60 detects that the electronic device 14A is executing the low-consumption mode, it can switch to the low-consumption mode in a manner linked with the electronic device 14A. Alternatively, when the mode switching unit 60 detects that the electronic device 14A has recovered from the low-consumption mode to the normal mode, it can recover to the normal mode in a manner linked with the electronic device 14A.

[0069] The action control unit 62 performs action control on the pen-side receiving circuit 46, the pen-side transmitting circuit 48, and the additional function unit 50 according to the action mode selected by the mode switching unit 60. The action control unit 62 performs action control while changing the driving parameters related to the specific driving action according to the selected action mode. As an example of a "specific driving action", there can be cited [1] a boost action of the downlink signal DS, [2] a transmitting action of the downlink signal DS, [3] a frequency hopping action of the downlink signal DS, [4] a receiving action of the uplink signal US, or [5] various actions related to the additional functions. The action control unit 62 can make the behavior triggered by the reception of the uplink signal US different between the case where the normal mode is being executed and the case where the low consumption mode is being executed.

[0070] The data writing unit 64 performs a function (hereinafter referred to as a writing function) of writing the required data (e.g., firmware) supplied by the communication with the electronic device 14A to the data storage unit 66. The data can be obtained by receiving the uplink signal US or by receiving the wireless signal WS. As driving parameters, [1] permission / prohibition of writing or [2] time, memory area, and data amount allocated for writing can be cited.

[0071] The pen-side receiving circuit 46 performs a receiving function of receiving the uplink signal US from the electronic device 14A. As driving parameters, [1] reception validity / invalidity or [2] reception frequency can be cited. The "invalidation of reception" includes stopping the receiving action or stopping the processing of received data.

[0072] The pen-side transmission circuit 48 performs a transmission function of transmitting a downlink signal DS to the electronic device 14A. Examples of driving parameters include [1] validity / invalidity of transmission, [2] transmission voltage (voltage value, presence or absence of voltage boost), [3] width of rectangular pulse, [4] transmission frequency, [5] continuation / stop of frequency hopping, or [6] clock frequency. This "invalidation of transmission" includes stopping the generation of the downlink signal DS or stopping the transmission operation.

[0073] The pen pressure sensor 26 performs a pen pressure detection function for detecting the pen pressure acting on the pen tip. Examples of drive parameters include [1] detection validity / invalidity, [2] pen pressure detection frequency, etc. The "invalidation of detection" includes stopping the output of the detection signal or stopping the transmission of the pen pressure value.

[0074] The communication chip 72 performs a communication function of communicating with the electronic device 14A in a communication method (wired or wireless) different from the electrostatic coupling method. Examples of the communication method include USB (Universal Serial Bus), Bluetooth (registered trademark), and NFC (Near Field Communication). Examples of the drive parameters include [1] whether to continue / stop communication or [2] the type of communication mode.

[0075] The pen switch 74 performs an operation detection function of detecting the user's operation state. Examples of drive parameters include [1] validity / invalidity of the operation or [2] identification information of a switch whose operation is valid.

[0076] The vibration device 76 performs a vibration function of vibrating the active pen 12A to reproduce a pseudo-writing feeling. Examples of drive parameters include [1] enabling / disabling of vibration, [2] vibration time and vibration level, and the like.

[0077] PMIC78 is used to monitor the power module 30 ( Figure 2 ) and supplies power to the pen-side controller 28a. The PMIC 78 measures the remaining power of the power module 30 sequentially and supplies the remaining power to the pen-side controller 28a.

[0078] <Description of the action>

[0079] The position detection system 10A in the first embodiment is configured as described above. Figure 5~Figure 9 While explaining. Figure 5 It is shown Figure 3 and Figure 4 A flowchart of an example of the mode switching operation of the pen-side controller 28a.

[0080] In step SP10, the pen-side controller 28a checks whether a signal is received from the electronic device 14A. If a signal has not been received (step SP10: No), the pen-side controller 28a remains in step SP10 until a signal is received. On the other hand, if a signal is received (step SP10: Yes), the pen-side controller 28a proceeds to the next step SP12.

[0081] exist Figure 5 In step SP12, the mode switching unit 60 obtains the mode flag included in the signal received in step SP10.

[0082] Figure 6 : is a diagram schematically showing a first common method of a mode flag. In the first common method, it is equivalent to a method in which the electronic device 14A generates a mode flag and then provides the mode flag to the active pen 12A. Here, as the structure of the electronic device 14A, the touch sensor 16, the sensor side controller 18a, the host processor 34 and the wireless module 36 are illustrated. In addition, as the structure of the active pen 12A, the pen side receiving circuit 46, the pen side sending circuit 48 and the communication chip 72 are illustrated.

[0083] First, the host processor 34 of the electronic device 14A acquires data including the remaining power level of the active pen 12A through communication with the active pen 12A, and generates a mode flag indicating an operation mode to be executed.

[0084] In the case of communication using active electrostatic coupling, the sensor-side controller 18a of the electronic device 14A generates an uplink signal US modulated by data including a mode flag, and transmits the uplink signal US from the sensor electrode formed by the touch sensor 16. Thereafter, the active pen 12A receives the uplink signal US via the pen-side receiving circuit 46, and acquires the data including the mode flag by demodulating the uplink signal US. In this way, the active pen 12A acquires the mode flag.

[0085] When wireless communication different from the active electrostatic coupling method is used, the sensor-side controller 18a of the electronic device 14A generates a wireless signal WS modulated by data including a mode flag, and transmits the wireless signal WS from the wireless module 36. Thereafter, the active pen 12A receives the wireless signal WS via the communication chip 72, and acquires the data including the mode flag by demodulating the wireless signal WS. In this way, the active pen 12A acquires the mode flag.

[0086] Figure 7 2 is a diagram schematically showing a second method of sharing a mode flag. The second method corresponds to a method in which the active pen 12A generates a mode flag and then provides the mode flag to the electronic device 14A.

[0087] First, the active pen 12A obtains its own power remaining amount and generates a mode flag indicating the operation mode to be executed. Then, the active pen 12A supplies the mode flag to the host processor 34 of the electronic device 14A by transmitting a downlink signal DS or a wireless signal WS modulated by data including the mode flag. It should be noted that at this point in time, the active pen 12A has not yet switched the operation mode.

[0088] In the case of communication using active electrostatic coupling, the sensor-side controller 18a of the electronic device 14A generates an uplink signal US modulated by data including a mode flag, and transmits the uplink signal US from the sensor electrode formed by the touch sensor 16. Thereafter, the active pen 12A receives the uplink signal US via the pen-side receiving circuit 46, and acquires the data including the mode flag by demodulating the uplink signal US. In this way, the active pen 12A acquires the mode flag.

[0089] When wireless communication different from the active electrostatic coupling method is used, the sensor-side controller 18a of the electronic device 14A generates a wireless signal WS modulated by data including a mode flag, and transmits the wireless signal WS from the wireless module 36. Thereafter, the active pen 12A receives the wireless signal WS via the communication chip 72, and acquires the data including the mode flag by demodulating the wireless signal WS. In this way, the active pen 12A acquires the mode flag.

[0090] In Figure 5 in step SP14, the mode switching unit 60 refers to the value of the mode flag obtained in step SP12 and selects one operation mode from a plurality of operation modes. When the "normal mode" is selected (step SP14: normal mode), the mode switching unit 60 proceeds to the next step SP16.

[0091] In step SP16, the motion control unit 62 performs motion control of each part according to the normal mode selected in step SP14. After that, the pen-side controller 28a returns to step SP10, and steps SP10, SP12, SP14, and SP16 are repeatedly executed during the period when the normal mode continues.

[0092] Returning to step SP14, when the "low power consumption mode" is selected (step SP14: low power consumption mode), the mode switching unit 60 proceeds to the next step SP18.

[0093] In step SP18, the motion control unit 62 performs motion control of each part according to the low power consumption mode selected in step SP14. After that, the pen-side controller 28a returns to step SP10, and steps SP10, SP12, SP14, and SP18 are repeatedly executed during the period when the low power consumption mode continues.

[0094] In this way, the pen-side controller 28a dynamically switches the operation mode of the active pen 12A by repeatedly executing Figure 5 steps SP10 to SP18.

[0095] Figure 8 is a diagram showing an example of the selection result of the operation mode. The horizontal axis of the curve graph represents time t (unit: minute), and the vertical axis of the curve graph represents the power supply margin (unit: %). Here, it is assumed that the threshold value of the power supply margin for switching the operation mode is set to "50%".

[0096] First, when t < t1, during the period when the power supply margin exceeds 50%, the normal mode is executed. After that, continuing to use the active pen 12A, when t = t1, taking the opportunity that the power supply margin drops to 50%, the mode is switched from the normal mode to the low power consumption mode. The power supply margin gradually decreases, and the charging of the power supply module 30 starts at the timing when it becomes less (t = t2). When t = t3, taking the opportunity that the power supply margin recovers to 50%, the mode is switched from the low power consumption mode to the normal mode.

[0097] After that, after the power supply margin reaches 100% (t = t4), the use of the active pen 12A is restarted (t = t5). When t5 < t < t6, during the period when the power supply margin exceeds 50%, the normal mode is executed. After that, the use of the active pen 12A continues. At t = t6, taking the opportunity that the power supply margin drops to 50%, the mode is switched from the normal mode to the low power consumption mode. In this way, even when the active pen 12A is continuously used in a state with a small power supply margin, by automatically switching to the low power consumption mode, the active pen 12A can be used for a longer time.

[0098] <Comparison between Normal Mode and Low Power Consumption Mode>

[0099] Fig. 9 It is a diagram schematically showing the differences in drive actions between operation modes in the first embodiment. [1] In the boosting action of the downlink signal DS, in the normal mode, the boosted voltage is set to Vs1, while in the low power consumption mode, the boosted voltage is set to Vs2 (< Vs1). [2] In the transmission action of the downlink signal DS, in the normal mode, the transmission rate is set to R1, while in the low power consumption mode, the transmission rate is set to R2 (< R1). [3] In the frequency hopping action of the downlink signal DS, in the normal mode, the frequency hopping is set to "ON", while in the low power consumption mode, the frequency hopping is set to "OFF". [4] In the reception action of the uplink signal US, in the normal mode, the reception is set to "ON" (two-way mode), while in the low power consumption mode, the reception is set to "OFF" (one-way mode).

[0100] [5] In the wireless communication action, in the normal mode, the wireless communication is set to "ON", while in the low power consumption mode, the wireless communication is set to "OFF". [6] In the pen pressure detection action of the active pen 12A, in the normal mode, the detection is set to "ON", while in the low power consumption mode, the detection is set to "OFF". [7] In the angle detection action of the active pen 12A, in the normal mode, the angle detection is set to "ON", while in the low power consumption mode, the angle detection is set to "OFF". [8] In the operation acceptance action of the pen switch 74, in the normal mode, the operation is set to "valid", while in the low power consumption mode, the operation is set to "invalid". [9] In the data writing action, in the normal mode, the writing is "allowed", while in the low power consumption mode, the writing is "restricted".

[0101] It should be noted that the above-mentioned driving parameter changes are not limited to one, and can be performed simultaneously in a combination of two or more as long as there is no technical contradiction. In addition, the low consumption mode can also be set by the level of power reserve (that is, reserve level), in which case the number of driving parameter changes can also be increased step by step according to the reserve level.

[0102] <Summary of First Embodiment>

[0103] As described above, the position detection system 10A in the first embodiment includes an electronic device 14A configured to include a capacitive touch sensor 16 in which a plurality of sensor electrodes are arranged in a planar shape, and an active pen 12A used together with the electronic device 14A. The active pen 12A includes a receiving circuit (here, a pen-side receiving circuit 46) for receiving an uplink signal US from the electronic device 14A, a transmitting circuit (that is, a pen-side transmitting circuit 48) for transmitting a downlink signal DS to the electronic device 14A, an additional function unit 50 for performing an additional function different from the reception of the uplink signal US and the transmission of the downlink signal DS, and a control unit (here, a pen-side MCU 40) for controlling the operation of the pen-side receiving circuit 46, the pen-side transmitting circuit 48, or the additional function unit 50 according to a plurality of operation modes including a normal mode and a low-power mode.

[0104] The normal mode is an action mode that consumes relatively more power associated with a specific driving action related to at least one of the reception of the uplink signal US, the transmission of the downlink signal DS, and the ancillary functions (for example, an action mode in which the execution frequency of the specific driving action is relatively high or the execution amount of the specific driving action is relatively large). The low consumption mode is an action mode that consumes relatively less power associated with a specific driving action (for example, an action mode in which the execution frequency of the specific driving action is relatively low or the execution amount of the specific driving action is relatively small).

[0105] With this configuration, various functions can be executed according to the remaining power of the active pen 12A. Specifically, by selecting the normal mode when the remaining power is high and selecting the low power mode when the remaining power is low, the active pen 12A can be operated for a longer time.

[0106] In addition, when the specific driving action is a boosting action of the downlink signal DS, the pen-side MCU 40 can [1] control the boosting action of the pen-side transmitting circuit 48 in normal mode by boosting the sending voltage of the downlink signal DS to a first voltage, and [2] control the boosting action of the pen-side transmitting circuit 48 in low consumption mode by boosting the sending voltage of the downlink signal DS to a second voltage lower than the first voltage or by stopping the boosting of the downlink signal DS.

[0107] In addition, in the case where the specific driving action is a boosting action of a downlink signal DS composed of multiple rectangular pulses, the pen-side MCU 40 can [1] control the boosting action of the pen-side transmitting circuit 48 in the normal mode in such a way that the degree of dullness of the rise or fall in the rectangular pulse of the boosted downlink signal DS becomes relatively smaller, and [2] control the boosting action of the pen-side transmitting circuit 48 in the low-consumption mode in such a way that the degree of dullness of the rise or fall in the rectangular pulse of the boosted downlink signal DS becomes relatively larger.

[0108] In addition, when the specific driving action is the sending action of the downlink signal DS, the pen-side MCU 40 can [1] control the sending action of the pen-side sending circuit 48 in the normal mode in such a manner that the sending frequency of the downlink signal DS becomes relatively high, and [2] control the sending action of the pen-side sending circuit 48 in the low-consumption mode in such a manner that the sending frequency of the downlink signal DS becomes relatively low.

[0109] In addition, when the specific driving action is a frequency hopping action of switching the transmission frequency of the downlink signal DS, the pen-side MCU40 can [1] control the frequency hopping action of the pen-side transmission circuit 48 in the normal mode so that the switching frequency of the transmission frequency is relatively high and the frequency hopping is continuously performed, and [2] control the frequency hopping action of the pen-side transmission circuit 48 in the low-consumption mode so that the switching frequency of the transmission frequency is relatively low and the frequency hopping is continuously performed or the frequency hopping is stopped.

[0110] In addition, in a case where a specific driving action is to switch the clock frequency related to the generation or transmission of the downlink signal DS and perform a sending action of the downlink signal DS, the pen-side MCU 40 can [1] control the sending action of the pen-side sending circuit 48 in normal mode by sending the downlink signal DS at a relatively high clock frequency, and [2] control the sending action of the pen-side sending circuit 48 in low consumption mode by sending the downlink signal DS at a relatively low clock frequency.

[0111] In addition, when the specific driving action is the receiving action of the uplink signal US, the pen-side MCU 40 can [1] control the receiving action of the pen-side receiving circuit 46 in a normal mode by continuously receiving the uplink signal US, and [2] control the receiving action of the pen-side receiving circuit 46 in a low-consumption mode by intermittently receiving the uplink signal US or invalidating the reception of the uplink signal US.

[0112] Furthermore, the pen-side MCU 40 can control the transmission operation of the pen-side transmission circuit 48 so as to transmit the downlink signal DS at a predetermined transmission cycle while the reception of the uplink signal US is disabled in the low power consumption mode.

[0113] In addition, the additional functions include at least one of a communication function for communicating with the electronic device 14A in a manner different from the active electrostatic coupling method, a pen pressure detection function for detecting the pen pressure applied to the pen tip of the active pen 12A, an operation detection function for detecting the operation state of a switch provided by the active pen 12A, a vibration function for vibrating the active pen 12A, and a write function for writing data supplied from the electronic device 14A to a memory. In this case, the pen-side MCU 40 can [1] control the operation of the additional function unit 50 in a manner of continuously performing the additional function in the normal mode, and [2] control the operation of the additional function unit 50 in a manner of intermittently performing the additional function or stopping the execution of the additional function in the low power consumption mode.

[0114] In addition, the pen-side MCU 40 may make the behavior triggered by the reception of the uplink signal US different between the case where the normal mode is being executed and the case where the low power consumption mode is being executed.

[0115] In addition, the electronic device 14A can select the operation mode of the active pen 12A based on the remaining power of the power supply (here, the power module 30) mounted on the active pen 12A, and generate a mode flag indicating the operation mode. In this case, the pen-side MCU 40 obtains the mode flag by receiving it from the electronic device 14A, and switches and executes the normal mode or the low power consumption mode according to the value of the mode flag.

[0116] In addition, the pen-side MCU 40 can switch and execute the normal mode or the low-power mode based on the remaining power of the power supply (here, the power module 30) mounted on the active pen 12A. In this case, the pen-side transmission circuit 48 transmits a downlink signal DS including a mode flag indicating the operating mode being executed to the electronic device 14A.

[0117] [Second embodiment]

[0118] Next, regarding the position detection system 10B according to the second embodiment, Figure 10~Figure 18 The position detection system 10B is equivalent to Figure 1 This is one embodiment of the position detection system 10 shown. This position detection system 10B is configured to include an active pen 12B and an electronic device 14B.

[0119] <Internal Structure of Electronic Device 14B>

[0120] Fig.1018 is a diagram showing an example of the internal structure of an electronic device 14B in the second embodiment. The electronic device 14B includes a touch sensor 16 , a sensor-side controller 18 b , and a host processor 34 .

[0121] The touch sensor 16 is a capacitive sensor (more specifically, a mutual capacitance sensor) in which a plurality of sensor electrodes 16X and 16Y are arranged in a planar shape. The touch sensor 16 is configured to include a plurality of sensor electrodes 16X for detecting the position in the X direction (X coordinate) and a plurality of sensor electrodes 16Y for detecting the position in the Y direction (Y coordinate). The linear sensor electrodes 16X are extended in the Y direction and are arranged at equal intervals while being separated from each other along the X direction. The linear sensor electrodes 16Y are extended in the X direction and are arranged at equal intervals while being separated from each other along the Y direction. In addition, the sensor electrodes 16X and 16Y are insulated by being sandwiched by an insulating substrate (not shown) made of glass or resin.

[0122] The sensor-side controller 18 b is connected to the touch sensor 16 , and includes a microcontroller unit (hereinafter referred to as sensor-side MCU 100 ), a logic circuit 101 , sensor-side transmission circuits 102 and 103 , a sensor-side reception circuit 104 , and a selection circuit 105 .

[0123] The sensor-side MCU 100 and the logic circuit 101 control the transceiver operation of the sensor-side controller 18b by controlling the sensor-side transmission circuits 102 and 103, the sensor-side reception circuit 104, and the selection circuit 105. The sensor-side MCU 100 is a control unit that selectively executes, for example, [1] an operation of supplying the pixel driving voltage Vcom to the selection circuit 105, [2] an operation of controlling the sensor-side transmission circuit 102 to transmit the finger detection signal FDS, [3] an operation of controlling the sensor-side reception circuit 104 to receive the finger detection signal FDS, [4] an operation of controlling the sensor-side transmission circuit 103 to transmit the uplink signal US to the active pen 12B, and [5] an operation of controlling the sensor-side reception circuit 104 to receive the downlink signal DS from the active pen 12B, by reading and executing a program from a memory of the sensor-side MCU 100. In addition, the logic circuit 101 is configured to generate control signals for the sensor-side transmission circuits 102 and 103, the sensor-side reception circuit 104, and the selection circuit 105 according to the control of the sensor-side MCU 100.

[0124] When the downlink signal DS is a “position signal” indicating the position of the active pen 12B, the sensor-side MCU 100 calculates the position coordinates (x, y) of the active pen 12B on the touch surface based on the reception strength at each of the plurality of sensor electrodes 16X and 16Y, and outputs the calculated position coordinates to the host processor 34. On the other hand, when the downlink signal DS is a “data signal” including transmission data, the sensor-side MCU 100 obtains the response data Res (specifically, the unique ID, pen pressure, on / off information of the pen switch, etc.) included in the data signal, and outputs the calculated position coordinates to the host processor 34.

[0125] The sensor-side transmission circuit 102 generates a finger detection signal FDS according to the control of the sensor-side MCU 100, and supplies it to each sensor electrode 16X through the selection circuit 105. The finger detection signal FDS is composed of, for example, K signals s1 to sK, each of which is composed of K pulses represented by "1" or "-1". The nth (n=1 to K) pulses of each signal s1 to sK constitute a pulse group pn, and each pulse constituting one pulse group pn is input in parallel from the sensor-side transmission circuit 102 to each sensor electrode 16X through the selection circuit 105.

[0126] The sensor-side transmission circuit 103 has a function of generating an uplink signal US under the control of the sensor-side MCU 100 and the logic circuit 101. Specifically, the sensor-side transmission circuit 103 includes a code string holding unit 110, a spread spectrum processing unit 111, and a transmission protection unit 112.

[0127] The code string holding unit 110 has a function of generating and holding a spreading code of a predetermined chip length having an autocorrelation characteristic based on a control signal ctrl_t1 supplied from the logic circuit 101. The spreading code held by the code string holding unit 110 is supplied to the spreading processing unit 111.

[0128] The spread spectrum processing unit 111 has a function of acquiring a transmission chip string of a predetermined chip length by modulating the spread spectrum code held by the code string holding unit 110 based on the command COM supplied via the sensor side MCU 100. The spread spectrum processing unit 111 supplies the acquired transmission chip string to the selection circuit 105 via the transmission protection unit 112.

[0129] The sending protection unit 112 has the function of inserting a protection period (that is, a period during which neither sending nor receiving is performed) required for switching the sending action and the receiving action between the sending period of the uplink signal US and the receiving period of the downlink signal DS based on the control signal ctrl_t2 supplied from the logic circuit 101.

[0130] The sensor side receiving circuit 104 receives the finger detection signal FDS transmitted by the sensor side transmitting circuit 102 or the downlink signal DS transmitted by the active pen 12B based on the control signal ctrl_r of the logic circuit 101. Specifically, the sensor side receiving circuit 104 includes an amplifier circuit 115, a detector circuit 116, and an analog-to-digital (AD) converter 117.

[0131] The amplifier circuit 115 amplifies and outputs the finger detection signal FDS or the downlink signal DS supplied from the selection circuit 105. The detection circuit 116 generates a voltage corresponding to the level of the output signal of the amplifier circuit 115. The AD converter 117 generates a digital signal by sampling the voltage output from the detection circuit 116 at a predetermined time interval. The digital signal output by the AD converter 117 is supplied to the sensor side MCU 100.

[0132] The selection circuit 105 is connected to the touch sensor 16, and performs a switching operation according to a control signal from the logic circuit 101. Specifically, the selection circuit 105 includes two switches 118x and 118y and two electrode selection circuits 119x and 119y.

[0133] The switch 118x is configured such that a common terminal is connected to any one of the T1 terminal, the T2 terminal, the R terminal, and the D terminal, and the switch 118y is configured such that a common terminal is connected to any one of the R terminal and the T terminal. The common terminal of the switch 118x is connected to the electrode selection circuit 119x, the T1 terminal is connected to the output end of the sensor side transmission circuit 102, the T2 terminal is connected to the output end of the sensor side transmission circuit 103, the R terminal is connected to the input end of the sensor side reception circuit 104, and the D terminal is connected to the output end of the sensor side MCU 100. The common terminal of the switch 118y is connected to the electrode selection circuit 119y, the T terminal is connected to the output end of the sensor side transmission circuit 103, and the R terminal is connected to the input end of the sensor side reception circuit 104.

[0134] The electrode selection circuit 119x is a switch element for selectively connecting the plurality of sensor electrodes 16X to the common terminal of the switch 118x. That is, the electrode selection circuit 119x is configured to simultaneously connect at least a portion of the plurality of sensor electrodes 16X to the common terminal of the switch 118x. The electrode selection circuit 119y is a switch element for selectively connecting the plurality of sensor electrodes 16Y to the common terminal of the switch 118y. That is, the electrode selection circuit 119y is configured to simultaneously connect at least a portion of the plurality of sensor electrodes 16Y to the common terminal of the switch 118y.

[0135] The selection circuit 105 is supplied with four control signals sTRx, sTRy, selX, and selY from the logic circuit 101. Specifically, the control signal sTRx is supplied to the switch 118x, the control signal sTRy is supplied to the switch 118y, the control signal selX is supplied to the electrode selection circuit 119x, and the control signal selY is supplied to the electrode selection circuit 119y. The logic circuit 101 controls the switch of the selection circuit 105 by the four control signals sTRx, sTRy, selX, and selY, thereby selectively performing [1] transmission and reception of the finger detection signal FDS or [2] transmission of the uplink signal US and reception of the downlink signal DS.

[0136] The host processor 34 is composed of a computing device including a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and an MPU (Micro-Processing Unit). The host processor 34 plays a role in executing the operating system of the electronic device 14B, various application programs such as drawing software, etc. by executing a program stored in a memory not shown in the figure. The drawing software includes a function of generating stroke data based on the coordinates successively supplied from the sensor-side controller 18b, rendering the stroke data, and displaying it on the display, and a function of adjusting the rendering result based on data such as the pen pressure value supplied from the sensor-side controller 18b (for example, a function of adjusting the line width according to the pen pressure value).

[0137] <Functional Block Diagram>

[0138] Fig.11 is with Fig.10 The sensor-side controller 18 b is a functional block diagram of the sensor-side controller 18 b. The sensor-side controller includes a mode switching unit 130 , a position detection unit 132 , and an output processing unit 134 .

[0139] The mode switching unit 130 switches and executes a plurality of operation modes that are a combination of touch scanning or pen scanning. The types of operation modes are divided into [1] a "first operation mode group" that is switched based on the detection result of the active pen 12B or the passive indicator, and [2] a "second operation mode group" that is switched based on the remaining power of the active pen 12B, as in the first embodiment. As in the first embodiment, the first operation mode group includes the STP mode or the exclusive mode, and the second operation mode group includes the normal mode or the low power consumption mode.

[0140] In the second embodiment, the low-power mode is divided into [1] an "active mode" for maintaining the pen function of the active pen 12B and [2] a "passive mode" for stopping the transmission of the downlink signal DS and making the active pen 12B function as a passive indicator. The sensor-side controller 18b performs at least one of [1] a fallback operation, [2] a touch priority operation, [3] a passivation operation, [4] a pseudo-activation operation, and [5] a signal reflection operation during the execution of the active mode or the passive mode. Each operation will be described in detail later.

[0141] The mode switching unit 130 refers to the remaining power information supplied from the active pen 12B, and selects an operation mode according to the size relationship between the remaining power and a predetermined threshold value. The "remaining power information" means a quantitative value or a qualitative value representing the remaining power of the active pen 12B. For example, the mode switching unit 130 selects the "normal mode" when the current remaining power exceeds the threshold value (50%), and on the other hand, selects the "low consumption mode" when the current remaining power is below the threshold value. It should be noted that more than two remaining power thresholds can be set, and a low consumption mode (or sub-mode) that consumes less power can be selected step by step as the remaining power decreases.

[0142] The position detection unit 132 detects the active pen 12B or the passive pointer (for example, Fig.10 The position detection unit 132 performs a driving action while changing a driving parameter related to a specific driving action according to the selected action mode. Examples of a "specific driving action" include various actions related to [1] sending an uplink signal US, [2] receiving a downlink signal DS, [3] calculating an angle of the active pen 12B, or [4] scanning the touch sensor 16.

[0143] Specifically, the position detection unit 132 includes a scan control unit 136 , a signal transmission unit 138 , a signal acquisition unit 140 , a touch detection unit 142 , and a pen detection unit 144 .

[0144] The scanning control unit 136 repeatedly executes various scanning processes by time division via the touch sensor 16. The various scanning processes include [1] "touch scanning" for detecting a passive indicator (e.g., finger F) that does not send a signal and [2] "pen scanning" for detecting an active pen 12B that sends a downlink signal DS. The touch scanning and pen scanning can be executed in a 1:1 ratio or in a ratio of n:m (n≠m).

[0145] The above-mentioned touch scan is performed to detect changes in electrostatic capacitance at sensor electrodes 16X and 16Y. This touch scan can be, for example, [1] a scan based on a "mutual capacitance method" that detects changes in mutual capacitance between sensor electrodes 16X and 16Y by sending a finger detection signal FDS from sensor electrode 16X and receiving the signal FDS at sensor electrode 16Y, or [2] a scan based on a "self capacitance method" that detects changes in electrostatic capacitance of each of sensor electrodes 16X and 16Y.

[0146] It should be noted that the scanning control unit 136 performs the scanning operation according to the driving parameters corresponding to the operation mode selected by the mode switching unit 130. Examples of the driving parameters include [1] the length of the time slot allocated to the touch scan (hereinafter, also referred to as the "touch time length") or [2] the length of the time slot allocated to the pen scan (hereinafter, also referred to as the "pen time length").

[0147] The signal transmission unit 138 transmits the desired signal for performing touch scanning or pen scanning from the sensor electrodes 16X and 16Y according to the transmission control of the scanning control unit 136. During the execution of the touch scanning, the signal transmission unit 138 generates a finger detection signal FDS for detecting the finger F, and outputs and transmits the finger detection signal FDS to the transmission electrode (here, one or more sensor electrodes 16X). During the execution of the pen scanning, the signal transmission unit 138 generates an uplink signal US for detecting the active pen 12B, and outputs and transmits the uplink signal US to the transmission electrode (here, one or more sensor electrodes 16X and 16Y).

[0148] It should be noted that the signal transmission unit 138 performs the transmission operation of the uplink signal US according to the driving parameters corresponding to the operation mode selected by the mode switching unit 130. As an example of the driving parameters, [1] the validity / invalidity of transmission, [2] the transmission voltage (voltage value, the presence or absence of boost), or [3] the transmission frequency of the uplink signal US can be cited. The "invalidation of transmission" includes stopping the generation of the uplink signal US or stopping the transmission operation.

[0149] The signal acquisition unit 140 receives or acquires the desired signal for touch scanning or pen scanning from the sensor electrodes 16X and 16Y according to the reception control of the scanning control unit 136. During the execution of the touch scanning, the signal acquisition unit 140 receives the finger detection signal FDS from the transmitting electrode from the receiving electrode (here, one or more sensor electrodes 16Y), and acquires the detection signal (or first detection signal) for detecting the presence or position of the finger F. During the execution of the pen scanning, the signal acquisition unit 140 receives the downlink signal DS from the active pen 12B from the receiving electrode (here, one or more sensor electrodes 16X and 16Y), and acquires the detection signal (or second detection signal) for detecting the presence or position of the active pen 12B.

[0150] It should be noted that the signal acquisition unit 140 performs the reception operation of the downlink signal DS according to the drive parameters corresponding to the operation mode selected by the mode switching unit 130. As an example of the drive parameters, [1] the validity / invalidity of reception or [2] the reception frequency of the downlink signal DS can be cited. The "invalidation of reception" includes stopping the reception operation or stopping the processing of the received data.

[0151] The touch detection unit 142 performs various signal processing on the first detection signal obtained by the signal acquisition unit 140 to detect the presence or position of the passive pointer (hereinafter collectively referred to as "touch position"). The signal processing includes [1] "threshold processing" for detecting the presence or absence of the finger F based on the magnitude relationship between the signal value of each position represented by the signal distribution and the threshold, [2] "recognition processing" for identifying the type of touch (for example, finger F, palm, or other object) based on the size or shape of the area detected by the threshold processing, or [3] "position calculation processing" for calculating the touch position by performing interpolation or approximation calculation on the signal distribution.

[0152] The pen detection unit 144 performs various signal processing on the second detection signal obtained by the signal acquisition unit 140 to detect the presence or position of the active pen 12B (hereinafter collectively referred to as "pen position"). This signal processing includes [1] "threshold processing" for detecting the presence or absence of the active pen 12B based on the magnitude relationship between the signal level at each position represented by the signal distribution and the threshold value, or [2] "position calculation processing" for detecting the pen position by performing interpolation operation or approximate operation on the signal distribution.

[0153] It should be noted that the pen detection unit 144 performs the pen position detection operation according to the drive parameters corresponding to the operation mode selected by the mode switching unit 130. An example of the drive parameters is a threshold value used in threshold processing.

[0154] After the output processing unit 134 generates position information including the pen position or the touch position calculated by the position detection unit 132, it transmits the data including the position information to the host processor 34 ( Fig.10 ) output. The output processing unit 134 may output data at a predetermined period (e.g., 120 Hz). In addition to the position information of the active pen 12B, the data may also include [1] information provided by the active pen 12B (e.g., pen ID, pen pressure, on / off information of the pen switch, etc.), [2] information calculated based on the position information (e.g., tilt angle, azimuth, speed, acceleration), and [3] identification information of the currently executed action mode.

[0155] It should be noted that the output processing unit 134 is configured to output data according to the drive parameters corresponding to the operation mode selected by the mode switching unit 130. Examples of the drive parameters include [1] the presence or absence of each data item and [2] the output frequency of data.

[0156] <Description of the action>

[0157] The position detection system 10B in the second embodiment is configured as described above. Figure 12 to Figure 18 While explaining. Fig.12 It is shown Fig.10 and Fig.11 A flowchart of an example of a mode switching operation of the sensor-side controller 18b.

[0158] exist Fig.12 In step SP30, the sensor side controller 18b confirms whether the detection timing has arrived. If the detection timing has not arrived (step SP30: No), the sensor side controller 18b stays in step SP30 until the detection timing arrives. On the other hand, if the detection timing has arrived (step SP30: Yes), the sensor side controller 18b proceeds to the next step SP32.

[0159] In step SP32 , the mode switching unit 130 obtains the latest remaining power level supplied from the active pen 12B.

[0160] In step SP34 , the mode switching unit 130 selects an operation mode to be executed based on the remaining power level acquired in step SP32 .

[0161] In step SP36, the mode switching unit 130 confirms the operation mode selected in step SP34. If the normal mode is selected (step SP36: normal mode), the mode switching unit 130 supplies a mode flag indicating "normal mode" to the position detection unit 132, and proceeds to the next step SP38.

[0162] In step SP38, the position detection unit 132 performs detection processing of the active pen 12B in the normal mode. Thereafter, the sensor-side controller 18b returns to step SP30, and repeatedly executes steps SP30, SP32, SP34, SP36, and SP38 while the normal mode continues.

[0163] Returning to step SP36 , when the low consumption mode is selected (step SP36 : low consumption mode), the mode switching unit 130 supplies the mode flag indicating the “low consumption mode” to the position detection unit 132 , and the process proceeds to the next step SP40 .

[0164] In step SP40, the position detection unit 132 performs detection processing of the active pen 12B in the low consumption mode. Then, the sensor-side controller 18b returns to step SP30, and repeatedly executes steps SP30, SP32, SP34, SP36, and SP40 while the low consumption mode continues.

[0165] In this way, the sensor-side controller 18b repeatedly executes Fig.12 The detection action of the active pen 12B is performed in real time through steps SP30 to SP40.

[0166] <Specific example of low power consumption mode>

[0167] Next, regarding a specific example of the low consumption mode, Figure 13~Figure 18 While explaining.

[0168] (First example: rollback action)

[0169] As a first example of the low power consumption mode, the retraction operation of the position detection system 10B will be described. The “retraction operation” means an operation of maintaining the operation of the active pen 12B in a state where the function or performance of the position detection system 10B is partially stopped.

[0170] Fig.13This is a diagram showing a first example of a comparison of drive operations between a normal mode and a low-power consumption mode. [1] In the transmission operation of the uplink signal US, in the normal mode, transmission is set to "ON", while in the low-power consumption mode, transmission is set to "OFF". [2] In the reception operation of the downlink signal DS, in the normal mode, reception is set to "ON", while in the low-power consumption mode, reception is set to "OFF". [3] In the threshold determination operation of the reception level, in the normal mode, the threshold is set to Th1, while in the low-power consumption mode, the threshold is set to Th2 (< Th1). [4] In the angle detection operation of the active pen 12B, in the normal mode, detection is set to "ON", while in the low-power consumption mode, detection is set to "OFF".

[0171] It should be noted that the above changes in drive parameters sometimes vary depending on [1] whether it is an active mode or a passive mode or [2] the behavior of the active pen 12B in the low-power consumption mode. For example, in the low-power consumption mode, it is also possible to set the transmission of the uplink signal US or the reception of the downlink signal DS to "ON". In this case, the active pen 12B can stop the transmission of the downlink signal DS corresponding to the uplink signal US by spontaneously stopping the transmission of the downlink signal DS or by cutting off the detection of the uplink signal US, thereby enabling the low-power consumption mode.

[0172] (Second example: Touch priority operation)

[0173] As a second example of the low-power consumption mode, the touch priority operation of the position detection system 10B will be described. This "touch priority operation" means an operation that gives priority to touch scanning when touch scanning and pen scanning are performed by time division.

[0174] Fig.14 This is a diagram showing a second example of a comparison of drive operations between a normal mode and a low-power consumption mode. More specifically, Fig.14 schematically shows Fig.11 the time progress of the scanning operation of the scanning control unit 136. It should be noted that the rectangles in the figure correspond to the time slots allocated for each scan.

[0175] The normal mode is an operation mode for performing one touch scan (TS) and one pen scan (PS) by time division. A time length of T1 (unit: ms) is allocated to the time slot for touch scanning. A time length of T2 (unit: ms) is allocated to the time slot for pen scanning. That is, [1] one touch scan with a time length of T1 and [2] one pen scan with a time length of T2 constitute one operation unit (cycle: Tc1 = T1 + T2).

[0176] The low power consumption mode is equivalent to an action mode in which two touch scans (TS) and one pen scan (PS) are executed by time division. The time length of T1 (unit: ms) is allocated to the time slot of the touch scan. The time length of T2 (unit: ms) is allocated to the time slot of the pen scan. In other words, [1] two touch scans with a time length of 2·T1 and [2] one pen scan with a time length of T2 constitute one action unit (cycle: Tc2=2·T1+T2).

[0177] Here, if the pen output rates in the normal mode and the low consumption mode are respectively set to R1 and R2 [Hz], R1 and R2 are calculated according to the following equations (1) and (2).

[0178] R1=1000 / Tc1=1000 / (T1+T2)‥‥(1)

[0179] R2=1000 / Tc2=1000 / (2·T1+T2)‥‥(2)

[0180] Here, when T2 is a positive value, the relationship R1>R2 is satisfied. Thus, by preferentially executing touch scanning in the low power consumption mode, the response frequency of the active pen 12B is relatively reduced, thereby suppressing the power consumption of the active pen 12B accordingly.

[0181] (Third example: passive action)

[0182] As a third example of the low power consumption mode, the passivation operation of the position detection system 10B will be described. This “passivation operation” means an operation for making the active pen 12B function as a “passive pointer”.

[0183] Fig.15 This is a first block diagram of the pen-side controller 28 b included in the active pen 12B in the second embodiment. The pen-side controller 28 b includes a pen-side MCU 160 , a first switch 42 , a second switch 44 , a pen-side receiving circuit 46 , a pen-side transmitting circuit 48 , an additional function unit 50 , and a third switch 162 .

[0184] The pen side MCU160 and Figure 3 The pen-side MCU 40 shown is also a unit that performs overall control of various parts of the active pen 12B. The pen-side MCU 160 performs switch control of the first switch 42 , the second switch 44 , and the third switch 162 according to the operating mode being executed.

[0185] The third switch 162 is a switch element configured to connect the common terminal side of the first switch 42 and the common terminal side of the second switch 44. The third switch 162 is controlled by supplying a third switch control signal SWC3 to the pen-side MCU 160 to selectively short-circuit the tip electrode 22 and the ring electrode 24 and release the short-circuit.

[0186] Next, the switch control associated with switching between the normal mode and the low power consumption mode will be described. In the normal mode, the pen-side MCU 160 performs switch control to keep the third switch 162 in the "off" state, and performs operation control of each part in the same manner as in the first embodiment.

[0187] After that, when the normal mode is changed to the low power consumption mode, the pen-side MCU 160 performs switch control so that the first switch 42 and the second switch 44 are kept in the "off" state and the third switch 162 is kept in the "closed" state. As a result, the tip electrode 22 and the ring electrode 24 are short-circuited. By increasing the volume of the conductor part that forms the electrostatic capacitance with the touch sensor 16, the detection of the active pen 12B as a passive indicator is easy and stable.

[0188] It should be noted that in Fig.15 In the embodiment, the case where the tip electrode 22 and the ring electrode 24 are short-circuited is cited as an example, but the present invention is not limited to this structure. For example, three or more pen electrodes may be short-circuited, or one pen electrode and the housing 32 may be short-circuited. When the tip electrode 22 and the housing 32 are short-circuited, the third switch 162 is provided between the common terminal side of the first switch 42 and the ground line connected to the housing 32.

[0189] <Example 4: Simulating automated actions>

[0190] As a fourth example of the low power consumption mode, the pseudo-activation operation of the position detection system 10B will be described. This "pseudo-activation operation" means an operation for pseudo-detecting as "active" even though the operation state of the active pen 12B is "passive".

[0191] Fig.16 : is a diagram showing an example of a signal waveform of a downlink signal DS. The downlink signal DS is composed of [1] a position detection signal, [2] a start signal, and [3] a data signal. The position detection signal is a burst signal for detecting the position of the active pen 12B. The start signal is a timing signal for determining the start time point of the data signal. The data signal is a signal obtained by encoding data including a pen pressure value using the presence or absence (binary) of a burst signal.

[0192] For example, the following case is assumed: regardless of whether the normal mode or the low-consumption mode is selected, the sensor-side controller 18 performs a receiving operation of the common downlink signal DS. When the operation state of the active pen 12B is "passive", the downlink signal DS is not transmitted, so the active pen 12B is not detected by the sensor-side controller 18. Therefore, by designing the circuit structure of the sensor-side controller 18, although the operation state of the active pen 12B is "passive", it can be detected as "active" in a simulated manner.

[0193] Fig.17 The sensor controller 18c includes a sensor receiving circuit 104, a sensor MCU 170, an oscillator circuit 172 (corresponding to a "signal generating circuit"), and a fourth switch 174 (corresponding to a "switch").

[0194] The sensor side MCU170 and Fig.10 The sensor-side MCU 100 shown is also a unit that performs overall control on each part of the sensor-side controller 18c. The sensor-side MCU 170 performs switch control of the fourth switch 174 according to the operating mode being executed.

[0195] The oscillation circuit 172 generates a continuous or intermittent burst signal according to the enable control of the sensor side MCU 170. The burst signal has the same Fig.16 The “position detection signal” of the downlink signal DS shown has the same waveform shape (that is, the same time length and frequency).

[0196] The fourth switch 174 is a switch element provided between the reference potential (that is, GND) side of the sensor side receiving circuit 104 and the output side of the oscillation circuit 172. The sensor side MCU 170 supplies a fourth switch control signal SWC4 to the fourth switch 174 to perform switch control, and selectively connects and disconnects the sensor side receiving circuit 104 and the oscillation circuit 172.

[0197] Next, the switch control associated with the switching between the normal mode and the low power consumption mode will be described. In the normal mode, the sensor-side MCU 170 supplies an "OFF" enable signal to the oscillation circuit 172 and performs switch control to keep the fourth switch 174 in the "OFF" state.

[0198] After that, when the normal mode is changed to the low-power mode, the sensor-side MCU 170 supplies an "ON" enable signal to the oscillation circuit 172, and performs switch control in a manner to keep the fourth switch 174 in the "closed" state. In this way, the burst signal generated by the oscillation circuit 172 overlaps the reference potential of the sensor-side receiving circuit 104. Thus, the sensor-side MCU 170 receives the downlink signal DS containing only the position detection signal through the sensor-side receiving circuit 104, and the active pen 12B can be detected in an analog manner.

[0199] It should be noted that in Fig.17 In the example, the case where the burst signal is superimposed on the reference potential (GND) of the sensor side receiving circuit 104 is cited, but the present invention is not limited to this structure. For example, the burst signal may be superimposed on the power supply potential (Vcc) of the sensor side receiving circuit 104. In this case, the fourth switch 174 is provided between the Vcc side of the sensor side receiving circuit 104 and the output side of the oscillation circuit 172.

[0200] <Example 5: Signal reflection action>

[0201] As a fifth example of the low power consumption mode, the signal reflection operation of the position detection system 10B will be described. The “signal reflection operation” means an operation for causing the electronic device 14B to simulate detection as an “active state” by reflecting the uplink signal US by the active pen 12B.

[0202] Fig.18 This is a second block diagram of the pen-side controller 28 c included in the active pen 12B in the second embodiment. The pen-side controller 28 c includes a pen-side MCU 180 , a first switch 42 , a second switch 44 , a pen-side receiving circuit 182 , a pen-side transmitting circuit 48 , and an additional function unit 50 .

[0203] The pen side MCU180 and Figure 3 The pen-side MCU 40 shown is also a unit that performs overall control of various parts of the active pen 12B. The pen-side MCU 180 performs switch control of the first switch 42 , the second switch 44 , and a fifth switch 186 described later, according to the operating mode being executed.

[0204] The pen-side receiving circuit 182 demodulates the uplink signal US induced by the tip electrode 22 or the ring electrode 24 and outputs the demodulated data to the pen-side MCU 180. Specifically, the pen-side receiving circuit 182 includes an amplifier circuit 184, a fifth switch 186, and a decoding processor 188.

[0205] The amplifier circuit 184 is a circuit for amplifying the uplink signal US induced in the tip electrode 22 or the ring electrode 24. The input end of the amplifier circuit 184 is connected to the R terminal of the first switch 42 and the second switch 44, and the ground end of the amplifier circuit 184 is connected to the housing 32.

[0206] The fifth switch 186 is a switch element configured to connect a common terminal to either an R terminal or a T terminal. The common terminal of the fifth switch 186 is connected to the amplifier circuit 184, the R terminal is connected to the decoding processor 188, and the T terminal is connected to the first switch 42 and the second switch 44. The fifth switch 186 is supplied with a fifth switch control signal SWC5 by the pen-side MCU 180 to perform switch control, and selectively performs reception and mirror transmission of the uplink signal US.

[0207] The decoding processor 188 performs a process of decoding the uplink signal US amplified by the amplifier circuit 184. The decoding processor 188 includes, for example, the waveform regenerator 52 and the correlation operator 54 ( Figure 3 ) has the same function.

[0208] Next, the switch control associated with the switching between the normal mode and the low-power mode is described. In the execution of the normal mode, for example, the pen-side MCU 180 performs switch control in such a manner that the first switch 42 is connected to the T terminal, the second switch 44 is connected to the R terminal, and the fifth switch 186 is connected to the R terminal. In this way, the pen-side controller 28c receives the uplink signal US via the ring electrode 24 and sends the downlink signal DS via the tip electrode 22.

[0209] Afterwards, when the normal mode is changed to the low-consumption mode, the pen-side MCU 180 performs switch control in such a manner that the first switch 42 is connected to the T terminal, the second switch 44 is connected to the R terminal, and the fifth switch 186 is connected to the T terminal. In this way, the pen-side controller 28c causes the uplink signal US sensed in the ring electrode 24 to pass through the second switch 44, the amplifier circuit 184, the fifth switch 186, and the first switch 42, and transmits the uplink signal US in a mirror image via the tip electrode 22. In this way, the supply of data to the pen-side MCU 180 can be cut off, and the processing operation amount of the pen-side MCU 180 can be reduced accordingly.

[0210] <Summary of Second Embodiment>

[0211] As described above, the position detection system 10B in the second embodiment includes an electronic device 14B including a capacitive touch sensor 16 in which a plurality of sensor electrodes 16X and 16Y are arranged in a planar shape, and an active pen 12B used together with the electronic device 14B. The active pen 12B includes a pen-side receiving circuit 46 for receiving an uplink signal US from the electronic device 14B, a pen-side transmitting circuit 48 for transmitting a downlink signal DS corresponding to the uplink signal US to the electronic device 14B, and a pen-side control unit (here, a pen-side MCU 40, 160, 180) for controlling the driving operation of the pen-side receiving circuit 46 or the pen-side transmitting circuit 48 according to a plurality of operation modes including a normal mode and a low-power mode.

[0212] The normal mode is an operation mode in which the transmission of the downlink signal DS is continuously performed, and the low-consumption mode is an operation mode in which the transmission of the downlink signal DS is stopped and the active pen 12B functions as a passive indicator. Due to such a configuration, various functions corresponding to the remaining power of the active pen 12B can be performed. Specifically, by selecting the normal mode when the remaining power is large and selecting the low-consumption mode when the remaining power is small, the operating time of the active pen 12B can be extended.

[0213] In addition, the pen-side MCU 40 may spontaneously stop the transmission of the downlink signal DS in the low power consumption mode, or stop the transmission of the downlink signal DS corresponding to the uplink signal US by shutting down the detection of the uplink signal US.

[0214] In addition, when the active pen 12B also has two or more pen electrodes (here, the tip electrode 22 and the ring electrode 24) for receiving an uplink signal US or sending a downlink signal DS and a switch (here, the third switch 162) provided between the connecting lines connecting the two or more pen electrodes to each other, the pen-side MCU 160 can perform switch control in normal mode so that the third switch 162 is in an open state, and perform switch control in low consumption mode so that the third switch 162 is in a closed state.

[0215] In addition, when the active pen 12B also has a shell 32 that at least accommodates a pen-side receiving circuit 46, a pen-side transmitting circuit 48 and a pen-side MCU160, a pen electrode (here is a tip electrode 22 or a ring electrode 24) for receiving an uplink signal US or sending a downlink signal DS, and a switch arranged between the connecting line connecting the pen electrode and the shell 32, the pen-side MCU160 can control the switch in a normal mode so that the switch is in an open state, and in a low-consumption mode so that the switch is in a closed state.

[0216] Furthermore, when the electronic device 14B further includes a sensor controller 18c that controls the driving operation of the touch sensor 16, the sensor controller 18c can perform the reception operation of the common downlink signal DS regardless of whether the normal mode or the low power consumption mode is selected.

[0217] In addition, the sensor side controller 18c may also include a sensor side receiving circuit 104 that receives a downlink signal DS via the sensor electrodes 16X and 16Y, a signal generating circuit (here, an oscillation circuit 172) that generates an analog signal that simulates the downlink signal DS, a switch (here, a fourth switch 174) provided between a reference potential side of the sensor side receiving circuit 104 and an output side of the oscillation circuit 172 or between a power supply potential side of the sensor side receiving circuit 104 and an output side of the oscillation circuit 172, and a sensor side control unit (here, the sensor side MCU 170) that performs switch control in a normal mode so that the fourth switch 174 is in an open state and in a low consumption mode so that the fourth switch 174 is in a closed state.

[0218] In addition, when the active pen 12B also has a switch (here is the fifth switch 186) for switching the output destination of the pen-side receiving circuit 46 to the pen-side MCU180 or the pen-side sending circuit 48, the pen-side MCU180 can perform switch control in normal mode in such a way that the output destination of the fifth switch 186 is connected to the pen-side MCU180, and perform switch control in low consumption mode in such a way that the output destination of the fifth switch 186 is connected to the pen-side sending circuit 48.

[0219] [Third Embodiment]

[0220] Next, regarding the position detection system 10C according to the third embodiment, Figure 19~Figure 21 The position detection system 10C is equivalent to Figure 1 This is one embodiment of the position detection system 10 shown. This position detection system 10C is configured to include an active pen 12C and an electronic device 14C.

[0221] <Structure and Action>

[0222] Fig.19 1 is a schematic diagram of the configuration of a position detection system 10C according to the third embodiment. At least one of the active pen 12C and the electronic device 14C is provided with a notification unit 200 that explicitly or implicitly notifies the user that the remaining power of the active pen 12C is low.

[0223] The active pen 12C has the same internal structure as that of the first embodiment (active pen 12A) or the second embodiment (active pen 12B). Fig.19In the example of FIG. 1 , the active pen 12C further includes an exposed output device 202 and a built-in output device 204. Here, the output devices 202 and 204 correspond to the above-mentioned reporting unit 200.

[0224] The exposed output device 202 outputs visual information that appeals to the user's vision. The output device 202 is composed of, for example, a display panel or a lamp. Examples of display panels include a transmissive liquid crystal panel, a reflective liquid crystal panel, an organic EL (Electro Luminescence) panel, or electronic paper. In particular, by using electronic paper, it is possible to keep the display content while stopping the supply of power in a low-consumption mode.

[0225] The built-in output device 204 outputs audible information that appeals to the user's hearing or tactile information that appeals to the user's tactile sense. The output device 204 is, for example, composed of a sound generator including a speaker or a vibration device including a vibrator. Examples of output sounds include buzzers, jingles, music, or voice guidance.

[0226] The electronic device 14C has the same internal structure as that of the first embodiment (electronic device 14A) or the second embodiment (electronic device 14B). Fig.19 In the example of FIG. 1 , the electronic device 14C is configured to include a touch sensor 16, a sensor-side controller 18c, a wireless module 36 of any structure, a host processor 206, and a display panel 208. Here, the display panel 208 is equivalent to the above-mentioned reporting unit 200. As an example of a display panel, a liquid crystal panel, an organic EL panel, or electronic paper can be cited.

[0227] Next, the reporting action accompanying the switching between the normal mode and the low consumption mode is described. Hereinafter, the state in which the power reserve exceeds the threshold is referred to as the "normal state", and the state in which the power reserve is below the threshold is referred to as the "low reserve state". In the third embodiment, the state in which the normal mode is being executed is equivalent to the "normal state", and the state in which the low consumption mode is being executed is equivalent to the "low reserve state".

[0228] The position detection system 10C does not perform reporting based on the reporting unit 200 during the execution of the normal mode, but performs explicit or implicit reporting based on the reporting unit 200 during the execution of the low-consumption mode. That is, the reporting unit 200 starts reporting to the user when the normal mode is changed to the low-consumption mode, and the reporting unit 200 stops reporting to the user when the low-consumption mode is changed to the normal mode.

[0229] Here, "explicit notification" means to draw the user's attention by outputting various information that is not performed in the normal mode in the low-consumption mode. Examples of "explicit notification" include displaying a message, displaying a remaining battery meter, lighting / flashing a light, outputting a notification sound, or generating vibrations. In addition, "implied notification" means to draw the user's attention by outputting various information in different ways depending on whether it is the normal mode or the low-consumption mode. Examples of "implied notification" include making the cursor 214 ( Fig. 20 ) are displayed differently.

[0230] Fig. 20 It is shown Fig.19 FIG. 1 is a diagram showing an example of a method for displaying the position of the active pen 12C. The electronic device 14C is configured to display a cursor 214 (equivalent to a "marker") indicating the position 212 of the active pen 12C in the display area 210 of the display panel 208 as the active pen 12C approaches. Specifically, the cursor 214 is not displayed when the height of the active pen 12C based on the touch surface 12s (hereinafter, also referred to as the "hovering height Hh") is greater than a height threshold, but the cursor 214 is displayed when the hovering height Hh becomes smaller than the height threshold.

[0231] Fig.21 2 is a diagram showing an example of a method for changing the display mode of the cursor 214. The horizontal axis of the graph represents the hovering height Hh (unit: mm), and the vertical axis of the graph represents the visual confirmation degree of the cursor 214. The visual confirmation degree is defined in such a way that the larger the value, the higher the visual confirmation degree, and the smaller the value, the lower the visual confirmation degree. A visual confirmation degree of zero value indicates a state in which the user cannot visually confirm the cursor 214 (that is, the non-display state of the cursor 214). The visual confirmation degree is adjusted in various ways, including, for example, [1] the lightness and chroma of the color of the cursor 214, [2] the size and shape, or [3] the presence or absence of an outline.

[0232] Here, in the normal mode (shown by a solid line), the height threshold is set to h1, and in the low power consumption mode (shown by a dotted line), the height threshold is set to h2. Here, since the magnitude relationship of h1>h2 is satisfied, the appearance sensitivity of the cursor 214 becomes relatively low in the low power consumption mode. That is, when the normal mode is changed to the low power consumption mode, the user can understand that the remaining power of the active pen 12C has decreased through the decrease in the appearance sensitivity of the cursor 214.

[0233] It should be noted that in Fig.21In the example of changing the height threshold according to the action mode being executed, the demonstration effect of the display method is described, but the demonstration effect of the display method is not limited to this method. For example, the height threshold may be constant, and the visual confirmation degree may be gradually increased as the value of the hovering height Hh decreases. Even when the visual confirmation degree of the cursor 214 is changed transiently, it is possible to implicitly report that the power remaining of the active pen 12C has decreased.

[0234] In addition, in reality, no ranging sensor for measuring the hovering height Hh is provided in the active pen 12C or the electronic device 14C. Therefore, in the threshold determination, a physical quantity related to the hovering height Hh, namely [1] the reception intensity of the uplink signal US or [2] the reception intensity of the downlink signal DS is used instead of the hovering height Hh. In this case, by making the reception sensitivity of the active pen 12C to the uplink signal US or the reception sensitivity of the electronic device 14C to the downlink signal DS relatively low in the low-consumption mode, it is possible to reproduce Fig.21 Changes in display mode shown.

[0235] <Summary of the Third Embodiment>

[0236] As described above, the position detection system 10C in the third embodiment includes an electronic device 14C that is configured to include a capacitive touch sensor 16 in which a plurality of sensor electrodes are arranged in a planar shape, an active pen 12C used together with the electronic device 14C, and a reporting unit 200 that is provided in the electronic device 14C or the active pen 12C and that explicitly or implicitly reports to a user that the remaining power of the power source provided in the active pen 12C is low.

[0237] The active pen 12C includes a receiving circuit (here, the pen-side receiving circuit 46) for receiving an uplink signal US from the electronic device 14C, a transmitting circuit (that is, the pen-side transmitting circuit 48) for transmitting a downlink signal DS to the electronic device 14C, an additional function unit 50 for performing additional functions different from the reception of the uplink signal US and the transmission of the downlink signal DS, and a control unit (here, the pen-side MCU 40) for controlling the operation of the pen-side receiving circuit 46, the pen-side transmitting circuit 48 or the additional function unit 50 according to a plurality of operation modes including a normal mode and a low-consumption mode.

[0238] Thus, by providing the notification unit 200 in the electronic device 14C or the active pen 12C, it is possible to notify the user when the remaining power of the active pen 12C is low, and to urge the user to take measures such as charging or replacing the power source.

[0239] In addition, in the case where the reporting unit 200 is a display panel 208 that displays a cursor 214 at the indicated position 212 of the active pen 12C, the display panel 208 can display a mark (here, the cursor 214) according to the size relationship between the distance between the active pen 12C and the touch sensor 16 or a physical quantity related to the distance and a first threshold in a normal state (or during the execution of a normal mode), and display the cursor 214 according to the size relationship between the distance or the physical quantity and a second threshold that is smaller than the first threshold in a low remaining state (or during the execution of a low consumption mode).

[0240] Furthermore, when the notification unit 200 is the display panel 208 that displays the cursor 214 at the indicated position 212 of the active pen 12C, the display panel 208 may display the mark (here, the cursor 214 ) differently in the normal state and the low margin state.

[0241] In addition, when the reporting unit 200 is an output device 202 or 204 provided in the active pen 12C, the output device 202 or 204 may output information appealing to vision, hearing or touch in a low residual state. In addition, the output device 202 may also be an electronic paper that displays visual information.

[0242] [Other embodiments]

[0243] It should be noted that, when the remaining power of the active pen 12 becomes low, the following countermeasures may be taken.

[0244] As a first countermeasure, it is possible to consider adding a power source to the active pen 12. Specifically, the active pen 12 may also be configured to be able to receive power from the main power source, namely the power module 30 ( Figure 2 ) is switched to a secondary power source such as a solar cell for use. Alternatively, the active pen 12 may be provided with a vibration generator that can generate electricity through the vibration of the pen body.

[0245] As a second countermeasure, a mechanical structure that enables operation even when the remaining power supply is low can be considered. Specifically, a position adjustment mechanism (e.g., a screw adjustment mechanism) that moves the pen electrode for transmitting the downlink signal DS closer to the pen tip can be provided in the active pen 12. Alternatively, a refill module for increasing capacitance or signal strength can be provided in the active pen 12.

[0246] Description of Reference Numerals

[0247] 10, 10A, 10B, 10C‥Position detection system, 12, 12A, 12B, 12C‥Active pen, 14, 14A, 14B, 14C‥Electronic device, 16‥Touch sensor, 18, 18a, 18b, 18c‥Sensor side controller, 28, 28a, 28b, 28c‥Pen side controller, 40, 160, 180‥Pen side MCU (Pen side control unit), 46, 182‥Pen side receiving circuit, 48‥Pen side transmitting circuit, 100, 170‥Sensor side MCU (Sensor side control unit), DS‥Downlink signal, US‥Uplink signal.

Claims

1. An active pen for use with an electronic device configured to include a capacitive touch sensor in which a plurality of sensor electrodes are arranged in a planar shape, wherein: have: A receiving circuit for receiving an uplink signal from the electronic device; a transmitting circuit, for transmitting a downlink signal to the electronic device; an additional function unit that performs an additional function different from the reception of the uplink signal and the transmission of the downlink signal; and a control unit that controls the operation of the receiving circuit, the transmitting circuit, or the additional function unit according to a plurality of operation modes including a normal mode and a low power consumption mode, The normal mode is an operation mode in which the execution frequency of a specific driving operation related to at least one of the reception of the uplink signal, the transmission of the downlink signal, and the additional function is relatively high or the execution amount of the specific driving operation is relatively large, The low power consumption mode is an operation mode in which the execution frequency of the specific driving operation is relatively low or the execution amount of the specific driving operation is relatively small.

2. The active pen according to claim 1, The specific driving operation is a voltage boost operation of the downlink signal, In the normal mode, the control unit controls the voltage boosting operation of the transmission circuit so that the transmission voltage of the downlink signal is boosted to a first voltage. In the low power consumption mode, the control unit controls the voltage boosting operation of the transmission circuit so as to boost the transmission voltage of the downlink signal to a second voltage lower than the first voltage or to stop boosting the downlink signal.

3. The active pen according to claim 1, The specific driving operation is a voltage boosting operation of the downlink signal composed of a plurality of rectangular pulses. In the normal mode, the control unit controls the voltage boosting operation of the transmission circuit so that the degree of blunting of the rising or falling edge of the rectangular pulse of the boosted downlink signal becomes relatively small. In the low power consumption mode, the control unit controls the voltage boosting operation of the transmission circuit so that a degree of blunting of a rising edge or a falling edge in the rectangular pulse of the boosted downlink signal becomes relatively large.

4. The active pen according to claim 1, The specific driving action is a transmission action of the downlink signal, In the normal mode, the control unit controls the transmission operation of the transmission circuit so that the transmission frequency of the downlink signal becomes relatively high. In the low power consumption mode, the control unit controls the transmission operation of the transmission circuit so that the transmission frequency of the downlink signal becomes relatively low.

5. The active pen according to claim 1, The specific driving operation is a frequency hopping operation for switching the transmission frequency of the downlink signal. In the normal mode, the control unit controls the frequency hopping operation of the transmission circuit so that the switching frequency of the transmission frequency is relatively high and the frequency hopping is continuously performed. In the low power consumption mode, the control unit controls the frequency hopping operation of the transmission circuit so that the switching frequency of the transmission frequency is relatively low and the frequency hopping is continued or stopped.

6. The active pen according to claim 1, The specific driving operation is a transmission operation of switching a clock frequency related to generation or transmission of the downlink signal and transmitting the downlink signal, In the normal mode, the control unit controls the transmission operation of the transmission circuit so that the downlink signal is transmitted at the relatively high clock frequency. In the low power consumption mode, the control unit controls the transmission operation of the transmission circuit so that the downlink signal is transmitted at the relatively low clock frequency.

7. The active pen according to claim 1, The specific driving action is a receiving action of the uplink signal, In the normal mode, the control unit controls the receiving operation of the receiving circuit so as to continue receiving the uplink signal. In the low power consumption mode, the control unit controls the reception operation of the reception circuit so as to intermittently receive the uplink signal or disable reception of the uplink signal.

8. The active pen according to claim 7, In the low power consumption mode, the control unit controls a transmission operation of the transmission circuit so that the downlink signal is transmitted at a predetermined transmission cycle while reception of the uplink signal is disabled.

9. The active pen according to claim 1, The additional functions include at least one of a communication function for communicating with the electronic device in a manner different from an electrostatic coupling method, a pen pressure detection function for detecting a pen pressure applied to a pen tip of the active pen, an operation detection function for detecting an operation state of a switch of the active pen, a vibration function for vibrating the active pen, and a write function for writing data supplied from the electronic device into a memory. In the normal mode, the control unit controls the operation of the additional function unit in such a manner that the additional function is continuously performed. In the low power consumption mode, the control unit controls the operation of the additional function unit so as to intermittently execute the additional function or stop the execution of the additional function.

10. The active pen according to claim 1, The control unit makes a behavior triggered by reception of the uplink signal different between a case where the normal mode is being executed and a case where the low power consumption mode is being executed.

11. The active pen according to claim 1, The electronic device selects an operation mode of the active pen based on a remaining power level of a power source mounted on the active pen, generates a mode flag indicating the operation mode, The control unit acquires the mode flag by receiving it from the electronic device, and switches to the normal mode or the low power consumption mode according to the value of the mode flag and executes the mode.

12. The active pen according to claim 1, The control unit switches to the normal mode or the low power consumption mode based on the remaining power level of the power source mounted on the active pen and executes the operation. The transmission circuit transmits the downlink signal including a mode flag indicating an operating mode being executed to the electronic device.

13. A position detection system comprising: An electronic device including a capacitive touch sensor in which a plurality of sensor electrodes are arranged in a planar shape; and An active pen, for use with the electronic device, The active pen has: A pen-side receiving circuit receives an uplink signal from the electronic device; a pen-side transmitting circuit, transmitting a downlink signal corresponding to the uplink signal to the electronic device; and The pen-side control unit controls the driving operation of the pen-side receiving circuit or the pen-side transmitting circuit according to a plurality of operation modes including a normal mode and a low-power mode. The normal mode is an operation mode in which the downlink signal is continuously transmitted. The low power consumption mode is an operation mode for stopping transmission of the downlink signal and causing the active pen to function as a passive pointer.

14. The position detection system according to claim 13, In the low power consumption mode, the pen-side control unit stops transmission of the downlink signal, or stops transmission of the downlink signal corresponding to the uplink signal by shutting down detection of the uplink signal.

15. The position detection system according to claim 13, The active pen also has: Two or more pen electrodes, used to receive the uplink signal or send the downlink signal; and A switch is provided between the connection lines connecting the two or more pen electrodes to each other, In the normal mode, the pen-side control unit performs switch control so that the switch is in an open state, and in the low power consumption mode, the pen-side control unit performs switch control so that the switch is in a closed state.

16. The position detection system according to claim 13, The active pen also has: A housing, at least accommodating the pen-side receiving circuit, the pen-side sending circuit and the pen-side control unit; a pen electrode, used to receive the uplink signal or send the downlink signal; and A switch is provided between the connecting wires connecting the pen electrode and the housing, In the normal mode, the pen-side control unit performs switch control so that the switch is in an open state, and in the low power consumption mode, the pen-side control unit performs switch control so that the switch is in a closed state.

17. The position detection system according to claim 13, The electronic device further includes a sensor-side controller for controlling a driving operation of the touch sensor. Regardless of whether the normal mode or the low power consumption mode is selected, the sensor-side controller performs a common reception operation of the downlink signal.

18. The position detection system according to claim 17, The sensor side controller comprises: a sensor-side receiving circuit that receives the downlink signal via the sensor electrode; A signal generating circuit, generating an analog signal simulating the downlink signal; a switch provided between a reference potential side of the sensor side receiving circuit and an output side of the signal generating circuit or between a power supply potential side of the sensor side receiving circuit and an output side of the signal generating circuit; and The sensor-side control unit performs switch control so that the switch is in an open state in the normal mode, and performs switch control so that the switch is in a closed state in the low power consumption mode.

19. The position detection system according to claim 13, The active pen further includes a switch for switching the output destination of the pen-side receiving circuit to the pen-side control unit or the pen-side sending circuit. In the normal mode, the pen-side control unit performs switch control in such a manner that the output destination of the switch is connected to the pen-side control unit, and in the low-consumption mode, the pen-side control unit performs switch control in such a manner that the output destination of the switch is connected to the pen-side sending circuit.

20. A position detection system comprising: An electronic device comprising a capacitive touch sensor in which a plurality of sensor electrodes are arranged in a planar shape; an active pen for use with the electronic device; and a reporting unit, which is provided in the electronic device or the active pen and reports to the user explicitly or implicitly that the remaining power of the active pen is low, The active pen has: A receiving circuit for receiving an uplink signal from the electronic device; a transmitting circuit, for transmitting a downlink signal to the electronic device; an additional function unit that performs an additional function different from the reception of the uplink signal and the transmission of the downlink signal; and a control unit that controls the operation of the receiving circuit, the transmitting circuit, or the additional function unit according to a plurality of operation modes including a normal mode and a low power consumption mode, The normal mode is an operation mode in which the execution frequency of a specific driving operation related to at least one of the reception of the uplink signal, the transmission of the downlink signal, and the additional function is relatively high or the execution amount of the specific driving operation is relatively large, The low power consumption mode is an operation mode in which the execution frequency of the specific driving operation is relatively low or the execution amount of the specific driving operation is relatively small.

21. The position detection system according to claim 20, The reporting unit is a display panel that displays a mark at the indicated position of the active pen. In the normal mode, the display panel displays the mark according to the distance between the active pen and the touch sensor or the magnitude relationship between a physical quantity related to the distance and a first threshold value. In the low power consumption mode, the display panel displays the mark according to a magnitude relationship between the distance or the physical quantity and a second threshold value that is smaller than the first threshold value.

22. The position detection system according to claim 20, The reporting unit is a display panel that displays a mark at the indicated position of the active pen. The display panel displays the mark in different ways in the normal mode and the low power consumption mode.

23. The position detection system according to claim 21, The reporting unit is an output device provided on the active pen, The output device outputs information appealing to the sense of sight, hearing or touch in the low-consumption mode.

24. The position detection system according to claim 23, The output device is an electronic paper that displays visual information.

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