Stylus, sensor controller, controller, system, and method

Abstract

The invention provides a stylus, a sensor controller, a controller, a system and a method. Even if a downlink signal is transmitted at the same transmission strength as in a contact state, the possibility of reception failure of the downlink signal in a hovering state can be reduced. The stylus of the present invention comprises: a core body; an electrode provided in the vicinity of the core; a transmission unit that transmits, by means of the electrode, a downlink signal including switching information SW1; and a control unit that determines whether the core is in a contact state in which the core is in contact with the operation surface or in a hovering state in which the core is not in contact with the operation surface, causes the transmission unit to transmit switch information SW1 (data (E)) at a first bit rate when the determination result is the contact state, and causes the transmission unit to transmit switch information SW2 (data (E)) at a second bit rate when the determination result is the hovering state. And causes the transmission unit to transmit the switching information SW1 (data (C)) at a second bit rate that is smaller than the first bit rate.

Description

[0001] This application is a divisional application of the application with application number 202210310479.3, filed on March 28, 2022, and invention name “Stylus pen, sensor controller, controller, system and method”. The application with application number 202210310479.3, invention name “Stylus pen, sensor controller, controller, system and method” is a divisional application of the application with application number 201680087935.5, filed on January 24, 2019, and invention name “Stylus pen and sensor controller”. Technical Field

[0002] The present invention relates to a stylus pen, a sensor controller, a controller, a system and a method, and more particularly to a stylus pen for sending a downlink signal in hovering and a sensor controller for receiving the downlink signal. Background Art

[0003] There is known a stylus pen configured to send a signal for position detection (position signal) and a signal including a unique ID, pen pressure, and various data (data signal) to a sensor controller. Hereinafter, the signals sent by the stylus pen to the sensor controller are collectively referred to as "downlink signals". Examples of styluses that send downlink signals are disclosed in Patent Documents 1 to 3.

[0004] In addition, when the user wants to use the stylus to input text or pictures, the stylus gradually approaches the touch surface of the electronic device including the sensor controller, and finally the core is in contact with the touch surface. The input of text and pictures using the stylus becomes possible when the core of the stylus is in contact with the touch surface. Hereinafter, the state in which the core of the stylus is in contact with the touch surface is referred to as the "contact" state, and the state in which the core of the stylus is not in contact with the touch surface is referred to as the "hover" state.

[0005] Patent Document 2 discloses a stylus pen that makes the transmission intensity of a position signal in a contact state smaller than that in a hovering state (Patent Document 2, paragraph 4, line 57 to paragraph 5, line 3).

[0006] Patent Document 3 discloses a stylus pen that transmits only a position signal and some additional signals intermittently at a predetermined period in a hovering state, and further transmits a signal indicating pen pressure in the intervals in a contact state (Patent Document 2, paragraph 13, line 33 to paragraph 14, line 46, Fig. 9 A~ Fig. 9 C).

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: International Publication No. 2015 / 111159

[0010] Patent Document 2: U.S. Patent No. 8773405

[0011] Patent Document 3: U.S. Patent No. 8536471 Summary of the invention

[0012] Problems to be solved by the invention

[0013] If the S / N ratio of the downlink signal received at the sensor within the touch surface is compared when the stylus is in a hovering state and when it is in a contact state, the S / N is smaller when it is in the hovering state. This is because, in the hovering state, the distance between the sensor and the stylus is large, and the attenuation of the downlink signal becomes larger. As a result, in the prior art, the sensor controller sometimes fails to receive the downlink signal when the stylus is in a hovering state, so it is desired to improve it.

[0014] In this regard, according to the technology described in Patent Document 2, it is believed that the possibility of failure to receive downlink signals in the hovering state can be reduced. This is because the reception strength of the downlink signal in the hovering state is greater than the reception strength in the contact state. However, according to this technology, there is another problem that a special transmitter corresponding to the variable transmission strength is required on the stylus side.

[0015] Therefore, one object of the present invention is to provide a stylus pen and a sensor controller that can reduce the possibility of receiving a downlink signal in a hovering state even if the downlink signal is transmitted with the same transmission strength as in a contact state.

[0016] Solutions to Solve Problems

[0017] A touch pen on one aspect of the present invention comprises: a core; an electrode, which is arranged near the core; a sending unit, which uses the electrode to send a signal including a first digital value; and a control unit, which controls the sending unit, wherein the control unit determines whether the core is in a contact state in contact with an operating surface or in a hovering state in contact with the operating surface, and when the result of the determination is the contact state, the sending unit sends the first digital value at a first bit rate, and when the result of the determination is the hovering state, the sending unit sends the first digital value at a second bit rate that is lower than the first bit rate.

[0018] The touch pen on another aspect of the present invention comprises: a core body; an electrode, which is arranged near the core body; a sending unit, which uses the electrode to send signals; and a control unit, which controls the sending unit, wherein the control unit controls the sending unit in a manner that sends signals in units of super frames including a specified number of frames, and the control unit controls the sending unit in a manner that uses the specified number of frames to respectively send frame numbers indicating the order of frames in the super frame.

[0019] A stylus pen according to another aspect of the present invention comprises: a core body; an electrode disposed near the core body; a sending unit utilizing the electrode to send a signal including a first digital value; and a control unit for determining whether the core body is in a contact state with an operating surface or in a hovering state without contact with the operating surface, and when the result of the determination is the contact state, the first digital value is sent using a first signal sending method, and when the result of the determination is the hovering state, the sending unit is caused to send the first digital value using a second signal sending method, and a decoding error rate of the second signal sending method is lower than a decoding error rate of the first signal sending method.

[0020] The sensor controller of the present invention uses a first demodulation method to obtain status information of the stylus from a signal received from the stylus. When the status information indicates that the stylus is in a hovering state, the first demodulation method is used to obtain a first digital value included after the status information. When the status information indicates that the stylus is in a contact state, the second demodulation method is used to obtain the first digital value included after the status information. The bit error rate of the second demodulation method is higher than the bit error rate of the first demodulation method.

[0021] Effects of the Invention

[0022] According to the present invention, the noise tolerance in the hovering state is improved, so it is possible to obtain the effects of reducing the non-detection rate of the downlink signal, reducing the bit error detection rate when demodulating or decoding the downlink signal, reducing the decoding error rate based on error correction, etc. Therefore, even if the downlink signal is transmitted with the same transmission strength as in the contact state, the possibility of receiving the downlink signal in the hovering state can be reduced.

[0023] Furthermore, according to the present invention, since each frame has a frame number, when the stylus pen divides one information into a plurality of frames and transmits the divided information, even if the divided information is received out of sequence, the sensor controller on the receiving side can restore the information based on the frame number. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 11 and 2 are diagrams showing the configuration of an electronic device 3 according to an embodiment of the present invention. (a) shows the operation of the electronic device 3 when detecting a touch of a finger F, and (b) shows the operation of the electronic device 3 when detecting a stylus pen 2 .

[0025] Figure 2 It is a diagram showing the structure of the electronic device 3 according to the embodiment of the present invention.

[0026] Figure 3 1 is a diagram showing the structure of a long burst signal, a burst signal, and a data signal transmitted by the stylus pen 2 according to the embodiment of the present invention.

[0027] Figure 4 1 and 1 , which are diagrams showing a sequence of signal transmission and reception between the stylus pen 2 and the sensor controller 31 when the stylus pen 2 is above the upward detection height AH. (a) shows when the sensor controller 31 sends a pen start signal, and (b) shows when the sensor controller 31 requests the transmission of a long burst signal.

[0028] Figure 5 The diagram is a diagram showing the sequence of signal transmission and reception between the stylus 2 and the sensor controller 31 in the stage where the stylus 2 is inside the sensing range SR and the sensor controller 31 has not yet determined the position of the stylus 2, (a) represents when the sensor controller 31 sends a pen start signal, (b) represents the case where the sensor controller 31 uses the linear electrode 30Y to receive the long burst signal sent by the stylus 2, and (c) represents the case where the sensor controller 31 uses the linear electrode 30X to receive the long burst signal sent by the stylus 2.

[0029] Figure 6 It is a diagram showing the sequence of signal transmission and reception between the stylus pen 2 and the sensor controller 31 after the stylus pen 2 is inside the sensing range SR and the sensor controller 31 has determined the position of the stylus pen 2, indicating when the stylus pen 2 in the hovering state sends a burst signal and a data signal (the data of the sending object is not an inherent ID).

[0030] Figure 7 The diagrams are for explaining the operation of the sensor controller 31 according to the embodiment of the present invention. (a) shows the first half of the full-range scan, (b) shows the second half of the full-range scan, and (c) shows the sector scan.

[0031] Figure 8 1 is a diagram showing the structure of the stylus pen 2 according to the embodiment of the present invention.

[0032] Fig. 9 1 is a flowchart showing the overall process performed by the sensor controller 31 when the stylus pen 2 is hovering according to the embodiment of the present invention.

[0033] Fig.10 1 is a diagram showing the format of a downlink signal transmitted by the stylus pen 2 according to the embodiment of the present invention.

[0034] Fig.11 1 is a process flowchart showing an uplink signal reception process and a downlink signal transmission process performed by the stylus pen 2 according to the embodiment of the present invention.

[0035] Fig.12 1 is a process flowchart showing a transmission process of an uplink signal and a reception process of a downlink signal performed by the sensor controller 31 according to the embodiment of the present invention.

[0036] Fig.13 1 is a process flowchart showing a transmission process of an uplink signal and a reception process of a downlink signal performed by the sensor controller 31 according to the embodiment of the present invention.

[0037] Fig.14 This is a diagram showing a first example of a method of transmitting each of data (A) to (C) and data (D) and (E) by the stylus pen 2 according to the embodiment of the present invention.

[0038] Fig.15 This is a diagram showing a second example of a method of transmitting each of data (A) to (C) and data (D) and (E) by the stylus pen 2 according to the embodiment of the present invention.

[0039] Fig.16 This is a diagram showing a third example of a method of transmitting data (A) to (C) and data (D) and (E) respectively by the stylus pen 2 according to the embodiment of the present invention.

[0040] Fig.17 This is a diagram showing a fourth example of a method of transmitting data (A) to (C) and data (D) and (E) respectively by the stylus pen 2 according to the embodiment of the present invention.

[0041] Fig.18 This is a diagram showing a fifth example of a method of transmitting data (A) to (C) and data (D) and (E) respectively by the stylus pen 2 according to the embodiment of the present invention.

[0042] Fig.19 This is a diagram showing a sixth example of a method of transmitting data (A) to (C) and data (D) and (E) respectively by the stylus pen 2 according to the embodiment of the present invention.

[0043] Fig. 20 1 is a diagram showing a structure of a stylus pen 2 according to a first modified example of the embodiment of the present invention.

[0044] Fig.21It is a processing flowchart showing the reception processing of uplink signals and the transmission processing of downlink signals performed by the stylus 2 according to the second modification of the embodiment of the present invention. Detailed Embodiment

[0045] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, hereinafter, with reference to Figure 1 to Figure 8 The outline of the structure and operation of the stylus 2 and the sensor controller 31 of this embodiment will be described, and then, with reference to Figure 9~Figure 19 The operations of the stylus 2 and the sensor controller 31 directly related to the features of the present invention will be described.

[0046] Figure 1 It is a diagram showing the structure of the electronic device 3 of this embodiment. The electronic device 3 is a computer having a touch surface (operation surface) such as a tablet terminal, and as shown in this figure, it is configured to include a sensor 30 and a sensor controller 31.

[0047] The sensor 30 is composed of a matrix electrode, and this matrix electrode includes M linear electrodes 30X (first electrodes) arranged inside the touch surface and N (N < M) linear electrodes 30Y (second electrodes). In a specific example, M = 72 and N = 46. The M linear electrodes 30X are arranged so as to extend at equal intervals in a first direction parallel to the touch surface. In addition, the N linear electrodes 30Y are arranged so as to extend at equal intervals in a second direction parallel to the touch surface and orthogonal to the first direction. Each linear electrode 30X and each linear electrode 30Y are respectively connected to the sensor controller 31.

[0048] The sensor 30 is arranged together with a display panel (not shown) such as a liquid crystal. The specific arrangement method of the sensor 30 on the display panel is arbitrary, but for example, there can be mentioned an Out-cell type in which the linear electrodes 30X, 30Y are arranged outside the liquid crystal display panel, an On-cell type in which the linear electrodes 30X, 30Y are arranged on the color filter glass or the substrate glass inside the display panel, and an In-cell type in which the driving electrodes (specifically, the common electrode or the pixel electrode) of the display panel also serve as one of the linear electrodes 30X, 30Y.

[0049] The sensor controller 31 is a control unit that uses the sensor 30 to detect the touch of the finger F (including the derivation of the position coordinates of the finger F within the touch surface) and the detection of the stylus 2 (including the derivation of the position coordinates of the stylus 2 within the touch surface) in a time-division manner.

[0050] Figure 1(a) shows the operation of the electronic device 3 when detecting the touch of a finger F. As shown in the figure, when detecting the touch of a finger F, the sensor controller 31 sequentially supplies a predetermined signal (hereinafter referred to as a "finger detection signal") to each of the plurality of linear electrodes 30Y, and sequentially scans the potential of each of the plurality of linear electrodes 30X, thereby detecting the finger detection signal that passes through the intersection with the linear electrode 30Y and reaches each linear electrode 30X. When the finger F approaches the vicinity of the intersection through which the finger detection signal passes, the amplitude of the finger detection signal detected in this way becomes smaller than when it does not approach. This is because, due to the capacitive coupling generated between the finger F and the linear electrodes 30X and 30Y, part of the current flowing through the linear electrodes 30X and 30Y flows toward the human body. The sensor controller 31 detects the touch of the finger F by detecting such a change in amplitude.

[0051] Figure 1 (b) shows the basic operation of the electronic device 3 when detecting the stylus pen 2. As shown in the figure, as a basic operation, the sensor controller 31 when detecting the stylus pen 2 uses the plurality of linear electrodes 30X and the plurality of linear electrodes 30Y as receiving electrodes in sequence to perform the detection operation of the signal (hereinafter referred to as the "downlink signal") sent by the stylus pen 2. Then, the stylus pen 2 is detected based on the detection result. It should be noted that in actual operation, sometimes only a part of the linear electrodes 30X and 30Y are used to detect the stylus pen 2, but this will be described later.

[0052] In order for the sensor controller 31 to detect the stylus 2, the stylus 2 needs to be close to the touch surface of the electronic device 3 to the extent that the sensor controller 31 can receive the downlink signal. The sensing range SR shown in the figure schematically represents the range in which the sensor controller 31 can receive the downlink signal. The sensor controller 31 receives the downlink signal when the stylus 2 enters the sensing range SR, thereby being able to detect the stylus 2. Hereinafter, the action of the stylus 2 moving from outside the sensing range SR to inside the sensing range SR is referred to as "pen drop". Pen drop is usually performed by the user's operation of bringing the stylus 2 close to the touch surface of the electronic device 3. In detail, the above-mentioned hovering state is a state in which the stylus 2 enters the sensing range SR by pen drop but has not yet contacted the touch surface.

[0053] In addition, even when the stylus pen 2 is outside the sensing range SR, it is sometimes possible to receive a signal (hereinafter referred to as an "uplink signal") sent by the sensor controller 31 toward the stylus pen 2. This is because a portion of the uplink signals (the pen start signal described later, the command signal indicating the transmission instruction of the long burst signal, etc.) is sent using the entire surface of the touch surface (one or both of all the linear electrodes 30X and all the linear electrodes 30Y). The uplink detection height AH shown in the figure indicates the limit of the height (distance from the touch surface) at which the stylus pen 2 can receive these uplink signals. The uplink detection height AH is a position higher than the upper limit of the sensing range SR (a position farther from the touch surface).

[0054] Figure 2 : is a diagram showing the structure of the electronic device 3 of the present embodiment. The plurality of linear electrodes 30X and the plurality of linear electrodes 30Y constituting the sensor 30 are configured to perform capacitive coupling with the stylus pen 2 and the finger F. When the finger F approaches the sensor 30, a part of the current flowing from the sensor controller 31 to the linear electrodes 30Y is absorbed by the finger F via the capacitive coupling. As a result, as described above, the amplitude of the finger detection signal detected at the linear electrode 30X becomes smaller, so the sensor controller 31 can detect the touch of the finger F. In addition, the sensor 30 is configured to be able to transmit and receive signals bidirectionally with the stylus pen 2 via the above-mentioned capacitive coupling.

[0055] like Figure 2 As shown, the sensor controller 31 is configured to include a transmission unit 60 , a selection unit 40 , a reception unit 50 , a logic unit 70 , and an MCU 80 .

[0056] The transmission unit 60 is a circuit that generates a finger detection signal at the timing of detecting the touch of the finger F and generates an uplink signal at the timing of detecting the stylus pen 2. The uplink signal includes a pen start signal for notifying the stylus pen 2 of the presence of the sensor controller 31 and a command signal indicating an instruction (command) to the stylus pen 2.

[0057] exist Figure 2 Only the functional blocks related to the generation of the uplink signal are shown in detail in the transmission unit 60. The functional blocks include a mode supply unit 61, a switch 62, a diffusion processing unit 63, a code string holding unit 64, and a transmission protection unit 65. It should be noted that, in particular, the mode supply unit 61 is described as being included in the transmission unit 60 in this embodiment, but it can also be included in the MCU 80.

[0058] The pen start signal is composed of a repetition of a predetermined detection pattern c1 and a predetermined segment pattern STP arranged at the end.

[0059] The detection pattern c1 is a pattern of symbol values ​​used by the stylus pen 2 to detect the presence of the sensor controller 31, and is known to the stylus pen 2 in advance (before the stylus pen 2 detects the sensor controller 31). A symbol is a unit of information used for modulation in the transmission process (a unit of information represented by the transmission signal), and is a unit of information obtained by demodulating one symbol as a received signal in the reception process. The value of the symbol can include a value converted into a bit string (hereinafter referred to as a "bit string corresponding value") and a value converted into a bit string by the stylus pen 2 that does not receive the symbol (hereinafter referred to as a "bit string non-corresponding value"). In a specific example, the detection pattern c1 is composed of a pattern "PM" composed of a combination of two bit string non-corresponding values ​​"P" and "M".

[0060] The separation pattern STP is a pattern of the value of the symbol used to notify the stylus 2 of the end of the repetition period of the detection pattern c1, and is composed of patterns that will not appear in the repetition of the detection pattern c1. The separation pattern STP is also known to the stylus 2 in advance (before the stylus 2 detects the sensor controller 31). As an example, when the detection pattern c1 is composed of the combination "PM" of two bit string non-corresponding values ​​"P" and "M" as described above, the separation pattern STP can be composed of a pattern "PP" in which the bit string non-corresponding value "P" is repeated twice. The structures of the separation pattern STP and the detection pattern c1 can also be reversed, and the separation mode is composed of "PM" and the detection mode c1 is composed of "PP".

[0061] The mode supply unit 61 holds the detection mode c1 and the separation mode STP, and is configured to output them in a prescribed order according to the instruction of the control signal ctrl_t1 supplied from the logic unit 70. Specifically, the detection mode c1 is continuously and repeatedly output during a prescribed continuous transmission period, and the separation mode STP is output immediately after the continuous transmission period ends. In this way, the transmission of the pen start signal is realized. It should be noted that the separation mode STP can also be output at the beginning of the command signal (described later) indicating the transmission instruction of the long burst signal.

[0062] The switch 62 has a function of selecting one of the mode supply unit 61 and the MCU 80 based on the control signal ctrl_t2 supplied from the logic unit 70 and supplying the output of the selected one to the diffusion processing unit 63. When the switch 62 selects the mode supply unit 61, the detection mode c1 or the segmentation mode STP is supplied from the mode supply unit 61 to the diffusion processing unit 63. On the other hand, when the switch 62 selects the MCU 80, the control information c2 is supplied from the MCU 80 to the diffusion processing unit 63.

[0063] The control information c2 is information indicating an instruction (command) for the stylus pen 2, and is generated by the MCU 80. The above-mentioned command signal is composed of the control information c2. The control information c2 includes the value of the symbol corresponding to the variable-length bit string (for example, 0 to 15), and is different from the detection mode c1 and the separation mode STP in that the value is not shared in advance with the stylus pen 2.

[0064] The code string holding unit 64 has a function of generating and holding a spreading code PN of a predetermined chip length having a self-correlation characteristic based on a control signal ctrl_t3 supplied from the logic unit 70. The spreading code PN held by the code string holding unit 64 is supplied to the diffusion processing unit 63.

[0065] The diffusion processing unit 63 has a function of obtaining a transmission chip string of a predetermined chip length by modulating the extension code PN held by the code string holding unit 64 based on the value of the symbol (detection mode c1, separation mode STP or control information c2) supplied via the switch 62. The diffusion processing unit 63 is configured to supply the obtained transmission chip string to the transmission protection unit 65.

[0066] The transmission protection unit 65 has a function of inserting a protection period (a period during which neither transmission nor reception is performed) required for switching transmission and reception operations between an uplink signal transmission period and a downlink signal reception period based on a control signal ctrl_t4 supplied from the logic unit 70 .

[0067] The receiving unit 50 is a circuit for receiving the finger detection signal transmitted by the transmitting unit 60 or the downlink signal transmitted by the stylus pen 2 based on the control signal ctrl_r of the logic unit 70 . Specifically, the receiving unit 50 includes an amplifier circuit 51 , a detector circuit 52 , and an analog-to-digital (AD) converter 53 .

[0068] The amplifier circuit 51 amplifies and outputs the signal (finger detection signal or downlink signal) supplied from the selection unit 40. The detector circuit 52 is a circuit that generates a voltage corresponding to the level of the output signal of the amplifier circuit 51. The AD converter 53 is a circuit that generates a digital signal by sampling the voltage output from the detector circuit 52 at a predetermined time interval. The digital signal output by the AD converter 53 is supplied to the MCU 80.

[0069] The signal reception processing performed by the detection circuit 52 includes a process of detecting the signal of a period corresponding to the length of the period of the signal sent by the stylus pen 2 (the first bit rate and the second bit rate described later) according to the hovering state or the contact state of the stylus pen. In addition, the MCU 80 obtains the data (the switch information SW1 described later, etc.) sent by the stylus pen 2 by determining the bit value of the signal using the demodulation method corresponding to the modulation method corresponding to the hovering state or the contact state. In addition, when the frame sent by the stylus pen 2 includes an error detection code, the MCU 80 performs error detection (or error correction) based on the error detection code when decoding the data (the switch information SW1 described later, etc.) sent by the stylus pen 2.

[0070] The selection unit 40 is configured to include switches 44x and 44y and conductor selection circuits 41x and 41y.

[0071] The switches 44x and 44y are respectively single-circuit double-contact switch elements configured to connect a common terminal to either a T terminal or an R terminal. The common terminal of the switch 44x is connected to the conductor selection circuit 41x, the T terminal is connected to the output end of the transmission unit 60, and the R terminal is connected to the input end of the reception unit 50. In addition, the common terminal of the switch 44y is connected to the conductor selection circuit 41y, the T terminal is connected to the output end of the transmission unit 60, and the R terminal is connected to the input end of the reception unit 50.

[0072] The conductor selection circuit 41x is a switch element for selectively connecting the M linear electrodes 30X to the common terminal of the switch 44x. The conductor selection circuit 41x is configured to simultaneously connect a part or all of the M linear electrodes 30X to the common terminal of the switch 44x.

[0073] The conductor selection circuit 41y is a switch element for selectively connecting the N linear electrodes 30Y to the common terminal of the switch 44y. The conductor selection circuit 41y is also configured to simultaneously connect a part or all of the N linear electrodes 30Y to the common terminal of the switch 44y.

[0074] Four control signals sTRx, sTRy, selX, and selY are supplied from the logic unit 70 to the selection unit 40. Specifically, the control signal sTRx is supplied to the switch 44x, the control signal sTRy is supplied to the switch 44y, the control signal selX is supplied to the conductor selection circuit 41x, and the control signal selY is supplied to the conductor selection circuit 41y. The logic unit 70 controls the selection unit 40 using these control signals sTRx, sTRy, selX, and selY to realize the transmission and reception of the finger detection signal, the transmission of the uplink signal including the pen start signal and the command signal, and the reception of the downlink signal. The control of the selection unit 40 by the logic unit 70 will be described in detail later.

[0075] The logic unit 70 and the MCU80 are control units that control the sending and receiving actions of the sensor controller 31 by controlling the sending unit 60, the receiving unit 50, and the selecting unit 40. Specifically, the MCU80 is a microprocessor that has ROM and RAM inside and operates based on a specified program. On the other hand, the logic unit 70 is configured to output the above-mentioned control signals based on the control of the MCU80. The MCU80 is also configured to perform the following processing: based on the digital signal supplied from the AD converter 53, coordinate data x, y, etc. representing the position of the finger F or the stylus 2 are derived, and output to the system controller of the electronic device 3; and when the digital signal supplied from the AD converter 53 represents a data signal, the data Res represented by the digital signal is obtained, and output to the system controller of the electronic device 3.

[0076] Hereinafter, the control of the selection unit 40 by the logic unit 70 will be described in detail.

[0077] First, the logic unit 70 controls the selection unit 40 using the control signals sTRx, sTRy, selX, and selY in order to sequentially connect the N linear electrodes 30Y to the output end of the transmission unit 60 and the M linear electrodes 30X to the input end of the reception unit 50 when transmitting and receiving the finger detection signal. Figure 1 As shown, finger detection signals are sequentially supplied to each of the N linear electrodes 30Y, and the finger detection signals reaching each linear electrode 30X through the intersection with the linear electrode 30Y are detected by the receiving unit 50 , thereby realizing detection of touch of the finger F.

[0078] When sending an uplink signal or receiving a downlink signal, the logic unit 70 performs different processing according to the detection state of the stylus pen 2 and the type of the downlink signal. The following first describes the type of the downlink signal and the sequence of signal transmission and reception between the stylus pen 2 and the sensor controller 31, and then describes in detail the operation of the logic unit 70 when sending an uplink signal or receiving a downlink signal.

[0079] Figure 3: is a diagram showing the types of downlink signals sent by the stylus pen 2 of an embodiment of the present invention. As shown in the figure, the downlink signal includes a long burst signal, a burst signal and a data signal. The long burst signal is a signal formed by continuously sending a signal of a predetermined pattern known in advance between the stylus pen 2 and the sensor controller 31, that is, a signal of a predetermined waveform within a predetermined time T1. The burst signal is a signal formed by continuously sending the signal of the predetermined waveform within a predetermined time T4 shorter than time T1. The data signal is a data signal formed by modulating the signal of the predetermined waveform by data, and is typically sent after the burst signal within a time equivalent to the difference T1-T4 between time T4 and time T1. It should be noted that the actual transmission of the data signal sometimes continues for a time longer than the difference T1-T4, but this will be described later. A predetermined gap signal (not shown) used to indicate the separation from the burst signal is inserted at the front of the burst signal. The type of the downlink signal sent by the stylus pen 2 is selected according to the instruction of the command signal sent by the sensor controller 31.

[0080] Figure 4~Figure 6 is a diagram showing a sequence of signal transmission and reception between the stylus pen 2 and the sensor controller 31, Figure 4 This shows that the stylus pen 2 is located above the upward detection height AH. Figure 5 2 shows a stage where the stylus pen 2 is inside the sensing range SR and the sensor controller 31 has not yet determined the position of the stylus pen 2. Figure 6 This shows that the stylus pen 2 is inside the sensing range SR and the sensor controller 31 has determined the position of the stylus pen 2. Each case will be described below in turn.

[0081] <When the stylus pen 2 is above the upward detection height AH>

[0082] Figure 4 (a) shows when the sensor controller 31 sends a pen start signal, Figure 4 (b) shows a case where the sensor controller 31 requests transmission of a long burst signal.

[0083] First, if Figure 4As shown in (a), the sensor controller 31 transmits the pen start signal within the time Ts (= t1-t0) from time t0 to time t1. This transmission is performed when the sensor controller 31 has not yet detected the stylus 2. As described above, the pen start signal is a signal including the repetition of the detection mode c1 and the segmentation pattern STP at the end. The stylus 2 intermittently performs the detection action of the detection mode c1 by intermittently performing the detection action of the symbols constituting the detection mode c1 (in the above example, "P" and "M"), but when it is above the upward detection height AH, the detection mode c1 cannot be detected even through this detection action. Therefore, the stylus 2 will only repeatedly perform the detection action of the detection mode c1.

[0084] The sensor controller 31 is connected after the pen start signal is sent, such as Figure 4 As shown in (b), the command signal starts at time t2 after time t1 (at Figure 4~Figure 6 and the following Fig.10 The time required for sending the command signal is T0 which is shorter than the above-mentioned time Ts. At the stage where the stylus pen 2 has not yet been detected, the sensor controller 31 sends a command signal indicating the sending of a long burst signal. However, the stylus pen 2 located above the upward detection height AH cannot receive the command signal, and therefore will not send a long burst signal according to the command signal, but will only repeat the detection action of the detection mode c1.

[0085] After the sensor controller 31 transmits the command signal indicating the transmission instruction of the long burst signal, it performs the detection operation of the long burst signal. This detection operation is equivalent to the first half of the full range scan described later, and is performed using the N linear electrodes 30Y in sequence. The details of the full range scan will be described later. Here, since the stylus pen 2 does not transmit the long burst signal, the long burst signal will of course not be detected by the sensor controller 31. The time that can be used as the detection operation of the long burst signal is the time T1 (=Ts-T0) equivalent to the difference between the time Ts and the time T0, but when the detection operation of the long burst signal is performed using the N linear electrodes 30Y in sequence, the detection operation of the long burst signal is temporarily completed at the time t3 before the time t4 (=t2+Ts) after the time T1. Therefore, the sensor controller 31, when the long burst signal is not detected during the detection operation, enters the sleep state between the time t3 and the time t4. As a result, the power consumption of the sensor controller 31 is reduced. After the time t4, the pen start signal is repeatedly transmitted.

[0086] <Stage where the stylus pen 2 is inside the sensing range SR and the sensor controller 31 has not determined the position of the stylus pen 2>

[0087] Figure 5 (a) shows when the sensor controller 31 sends a pen start signal, Figure 5 (b) shows a case where the sensor controller 31 uses the linear electrode 30Y to receive the long burst signal sent by the stylus pen 2 . Figure 5 (c) shows a case where the sensor controller 31 receives the long burst signal transmitted by the stylus pen 2 using the linear electrode 30X.

[0088] When Figure 5 When the pen is put down (time t6) as shown in (a), the stylus pen 2 can detect the detection mode c1 by the detection action of the detection mode c1 performed later (time t7). The stylus pen 2 that has detected the detection mode c1 continues the detection action until the segmented mode STP is detected. And when the segmented mode STP is detected, synchronization is performed with the sensor controller 31 based on the detection time. This synchronization is specifically performed by creating a transmission and reception schedule described later.

[0089] It should be noted that Figure 5 (a) shows an example in which a pen-down operation is performed at time t6 between time t5 when the pen start signal is sent and time t8 (= t5 + Ts) when the pen start signal is sent, and the stylus pen 2 detects the detection pattern c1 at time t7 before reaching time t8. However, even if a pen-down operation is performed while the sensor controller 31 is performing a detection operation of a long burst signal (for example Figure 5 At time t6 ′) shown in (b), the same process is performed only by slightly delaying the detection timing of the detection pattern c1 by the stylus pen 2 .

[0090] Then, if Figure 5 As shown in (b), when the sensor controller 31 starts to send a command signal indicating the sending of a long burst signal at time t9 after time t8, the stylus pen 2 receives the command signal and continuously sends the long burst signal within a time T1 until time t10 (= t9 + Ts). The sensor controller 31 detects the stylus pen 2 by detecting the long burst signal sent in this way.

[0091] Specifically, first Figure 5 As shown in (b), N linear electrodes 30Y are used sequentially to perform the long burst signal detection operation (the first half of the full range scan described later). At this time, a long burst signal is detected at one or more linear electrodes 30Y, so the sensor controller 31 stores the detection strength of the long burst signal at each linear electrode 30Y. Figure 5As shown in (c), the sensor controller 31 starts sending the command signal indicating the sending of the long burst signal again at time t11 after time t10, and performs the detection action of the long burst signal again at the same time as the sending is completed. This detection action is implemented using M linear electrodes 30X in sequence until time t12 (= t11 + Ts) (the second half of the full range scan described later). Through this detection action, a long burst signal is detected at one or more linear electrodes 30X, so the sensor controller 31 stores the detection strength of the long burst signal at each linear electrode 30X. Then, based on the detection strength of the long burst signal at each linear electrode 30Y previously stored and the detection strength of the long burst signal at each linear electrode 30X stored this time, the position coordinates of the stylus 2 on the touch surface are derived.

[0092] <After the stylus pen 2 is inside the sensing range SR and the sensor controller 31 determines the position of the stylus pen 2>

[0093] Figure 6 The figure shows the case where the stylus pen 2 in the hovering state sends a burst signal and a data signal (the data to be sent is not a unique ID). It should be noted that the case where the stylus pen 2 is in the above-mentioned contact state and the case where the data to be sent is a unique ID will be described in detail later.

[0094] like Figure 6 As shown, the sensor controller 31 that has determined the position of the stylus pen 2 starts to send a command signal indicating the transmission of data at the subsequent time t13. The stylus pen 2 that has received the command signal first continuously sends a burst signal within a time T4. The sensor controller 31 detects the burst signal and derives the position coordinates of the stylus pen 2 based on the detected burst signal. The burst signal detection operation is performed sequentially using the linear electrodes in the M linear electrodes 30X and the N linear electrodes 30Y that are located near the stylus pen 2 as indicated by the position coordinates of the stylus pen 2 that have just been derived (sector scanning described later). The stylus pen 2 sends a data signal including the indicated data after the burst signal. The sensor controller 31 obtains the data sent by the stylus pen 2 by receiving and decoding the data signal. The reception of the data signal is performed using only one linear electrode 30X or linear electrode 30Y corresponding to the position coordinates of the stylus pen 2 that have just been derived.

[0095] return Figure 2 , the operation of the logic unit 70 when detecting the stylus pen 2 and performing two-way communication with the stylus pen 2 is described in detail.

[0096] When a pen start signal and a command signal indicating a transmission instruction of a long burst signal are transmitted ( Figure 4 (a) (b) Figure 5The logic unit 70 of (a), (b), and (c) controls the selection unit 40 in such a manner that all of the M linear electrodes 30X or all of the N linear electrodes 30Y or both are used at the same time. Specifically, the selection unit 40 is controlled using the control signals sTRx, sTRy, selX, and selY so that the output end of the transmission unit 60 is simultaneously connected to one or both of the M linear electrodes 30X and the N linear electrodes 30Y. As a result, the pen start signal and the command signal indicating the transmission instruction of the long burst signal are respectively transmitted to the entire touch surface, so that the stylus pen 2 can be used regardless of whether it is in a state of Figure 1 These signals can be received anywhere within the sensing range SR shown.

[0097] Also like Figure 4 (b) and Figure 5 As shown in (b), when a long burst signal is received at a stage where the stylus pen 2 has not yet been detected ( Figure 4 (b) Figure 5 (b)) The logic unit 70 controls the selection unit 40 in such a way that the N linear electrodes 30Y are used in sequence. Specifically, the selection unit 40 is controlled using the control signals sTRy and selY so that the N linear electrodes 30Y are connected to the input end of the receiving unit 50 in sequence. As a result, the sensor controller 31 controls the selection unit 40 regardless of whether the stylus pen 2 is in a state Figure 1 Anywhere within the sensing range SR shown can receive the long burst signal sent by the stylus pen 2 , thereby detecting the stylus pen 2 .

[0098] Figure 7 (a) is a diagram for explaining the operation of the sensor controller 31 in this case. As shown in the figure, the sensor controller 31 in this case sequentially scans the N linear electrodes 30Y. The reason why the M linear electrodes 30X are not scanned at this stage is that the entire surface of the sensor 30 can be scanned even with only the N linear electrodes 30Y, and in addition, the scanning time of each electrode is extended.

[0099] Also like Figure 5 As shown in (c), after the stylus pen 2 is detected by receiving the long burst signal, when the long burst signal is received at the stage where the position coordinates of the stylus pen 2 have not yet been derived ( Figure 5 (c)) The logic unit 70 controls the selection unit 40 in such a manner that the M linear electrodes 30X are used sequentially. Specifically, the selection unit 40 is controlled using the control signals sTRx and selX so that the M linear electrodes 30X are sequentially connected to the input end of the receiving unit 50. The sensor controller 31 derives the position coordinates of the stylus pen 2 on the touch surface as described above based on the result of this control and the detection result of the long burst signal by the N linear electrodes 30Y previously implemented.

[0100] Figure 7(b) is a diagram for explaining the operation of the sensor controller 31 in this case. As shown in this diagram, the sensor controller 31 in this case sequentially scans M linear electrodes 30X. Figure 7 (a) shows the scanning (first half) and Figure 7 The scanning (second half) using the M linear electrodes 30X in sequence shown in (b) is collectively referred to as “full range scanning”.

[0101] When the command signal is sent after the position coordinates of the stylus pen 2 are derived ( Figure 6 ) controls the selection unit 40 so that only the linear electrodes in the vicinity of the stylus pen 2 are used among the M linear electrodes 30X and the N linear electrodes 30Y. Specifically, if it is assumed that the stylus pen 2 is located at the intersection of the j+5th linear electrode 30X and the i+5th linear electrode 30Y, the selection unit 40 is controlled using the control signals sTRx, sTRy, selX, and selY so that the jth to j+10th linear electrodes 30X and the ith to i+10th linear electrodes 30Y, which are five electrodes each on both sides, are simultaneously connected to the output end of the transmission unit 60. Thus, the command signal can be transmitted using only the linear electrodes in the vicinity of the stylus pen 2, and thus the power consumption for transmitting the command signal can be reduced. In addition, when a command signal is supplied to a palm or the like placed on the touch surface, the ground potential supplied to the stylus pen 2 increases, and as a result, the detection accuracy of the stylus pen 2 for the uplink signal may decrease. However, by sending the command signal only using linear electrodes located near the stylus pen 2 as described above, the possibility of supplying the command signal to the palm or the like decreases, thereby preventing the detection accuracy of the stylus pen 2 for the uplink signal from decreasing.

[0102] After the position coordinates of the stylus pen 2 are derived, when a normal burst signal other than a long burst signal is received ( Figure 6 ) controls the selection unit 40 so that only the linear electrodes in the M linear electrodes 30X and the N linear electrodes 30Y that are near the stylus pen 2 are used in sequence. Specifically, if, for example, the stylus pen 2 is located at the intersection of the j+5th linear electrode 30X and the i+5th linear electrode 30Y, then, for example, Figure 6 As shown, the selection unit 40 is controlled using control signals sTRx, sTRy, selX, and selY so that the range of five lines from here to both sides, that is, the jth to j+10th linear electrodes 30X and the ith to i+10th linear electrodes 30Y are sequentially connected to the input end of the receiving unit 50. As a result, the reception time of each linear electrode can be extended, so that the burst signal can be received more reliably.

[0103] Figure 7 (c) is a diagram for explaining the operation of the sensor controller 31 in this case. In this example, it is also assumed that the stylus pen 2 is located at the intersection of the j+5th linear electrode 30X and the i+5th linear electrode 30Y. The sensor controller 31 of this example only sequentially scans the 11 linear electrodes 30X from the jth to the j+10th and the 11 linear electrodes 30Y from the ith to the i+10th among the M×N linear electrodes, and derives the position coordinates of the stylus pen 2 based on the results. Hereinafter, such a scan that uses both a part of the M linear electrodes 30X and a part of the N linear electrodes 30Y to derive (update) the position coordinates of the stylus pen 2 derived once is referred to as a "sector scan".

[0104] When receiving data signal ( Figure 6 ) controls the selection unit 40 so as to use only one linear electrode 30X or linear electrode 30Y corresponding to the position of the stylus pen 2 derived by the burst signal just now. Specifically, the selection unit 40 is controlled using the control signals sTRx, sTRy, selX, and selY so as to connect the one linear electrode 30X or linear electrode 30Y to the input end of the receiving unit 50. In this way, the transmission time (=T1-T4) of the data signal can be fully utilized for transmitting data from the stylus pen 2 to the sensor controller 31.

[0105] The operation of the logic unit 70 when detecting the stylus pen 2 and performing bidirectional communication with the stylus pen 2 has been described above.

[0106] Figure 8 2 is a block diagram showing the functional blocks of the stylus pen 2 according to the present embodiment. As shown in the figure, the stylus pen 2 includes a core 20 , an electrode 21 , a switch 22 , a writing pressure detection sensor 23 (writing pressure detection unit), and a signal processing unit 24 .

[0107] The core 20 is an insulating member constituting the tip of the stylus pen 2. The electrode 21 is a conductive member provided near the core 20 (particularly near the tip), and functions as an antenna for transmitting downlink signals, and also functions as an antenna for receiving uplink signals transmitted from the sensor controller 31 via the coupling capacitor. It should be noted that the electrode for transmitting downlink signals and the electrode for receiving uplink signals may be the same electrode or different electrodes.

[0108] The switch 22 is a side switch provided on the side of the stylus pen 2 or a tail switch provided at the rear end thereof, which is switched on or off by a user's operation. The pen pressure detection sensor 23 is a pressure sensor for detecting pressure (pen pressure) applied to the tip of the core 20 .

[0109] The signal processing unit 24 has the following functions: receiving an uplink signal from the sensor controller 31 via the electrode 21, performing processing corresponding to the content, and generating a downlink signal to be sent to the sensor controller 31, and sending it toward the sensor controller 31 via the electrode 21. Specifically, the function is configured to include a switching unit 76, a receiving unit 71, a transmitting unit 75, and a control unit 90. Below, these functional blocks are described in turn.

[0110] The switch unit 76 is a single-circuit double-contact switch element configured such that a common terminal is connected to either a T terminal or an R terminal. The common terminal of the switch unit 76 is connected to the electrode 21, the T terminal is connected to the output terminal of the transmitter 75, and the R terminal is connected to the input terminal of the receiver 71. The state of the switch unit 76 is controlled by a control signal SWC from the control unit 90. When receiving an uplink signal from the sensor controller 31, the control unit 90 controls the switch unit 76 by the control signal SWC so that the R terminal is connected to the common terminal. When transmitting a downlink signal to the sensor controller 31, the control unit 90 controls the switch unit 76 by the control signal SWC so that the T terminal is connected to the common terminal. In the initial state, that is, until the stylus pen 2 detects the above-mentioned detection mode c1, the control unit 90 fixes the switch unit 76 in the state where the R terminal is connected to the common terminal, and then enters the sleep state in order to reduce the power consumption of the stylus pen 2.

[0111] The receiving unit 71 is a circuit that receives the signal (the signal that reaches the electrode 21) supplied from the switching unit 76 and decodes the value of the symbol contained in the received signal, and is configured to include a waveform regeneration unit 71a and a correlation operator 71b. The receiving unit 71 is configured to be able to detect the above-mentioned detection mode c1, segmentation mode STP, and control information c2 respectively through the decoding. In order to reduce the power consumption of the stylus pen 2, the receiving unit 71 performs the receiving operation only intermittently until the detection mode c1 is detected.

[0112] The waveform regeneration unit 71a converts the level of the charge (voltage) induced in the electrode 21 into a binary string (chip string) of positive and negative polarity values ​​at a clock that is several times (e.g., 4 times) the chip rate of the above-mentioned spreading code PN, and outputs it. The correlation operator 71b stores the chip string output by the waveform regeneration unit 71a in a register, and performs a correlation operation with the spreading code PN (or a code obtained by performing at least one of inversion and cyclic shift on the spreading code PN) while sequentially shifting it using the above-mentioned clock, thereby decoding the value of the symbol included in the received signal.

[0113] The receiving unit 71 successively determines whether the value of the symbol decoded by the correlation operator 71b indicates the above-mentioned detection mode c1. When the detection mode c1 is detected as a result, the sensor controller 31 issues a start signal EN to the control unit 90 for enabling the execution of the processing corresponding to the command indicated by the command signal.

[0114] When the receiving unit 71 detects the detection mode c1, it switches the receiving operation from intermittent operation to continuous operation, and checks whether the decoded symbol value indicates the above-mentioned segmentation mode STP. When the segmentation mode STP is detected as a result, the receiving unit 71 outputs the detection time t2 to the control unit 90.

[0115] After detecting the segmentation mode STP, the receiving unit 71 performs the receiving operation of the command signal sent by the sensor controller 31 according to the scheduling (described later) of the control unit 90. Specifically, the values ​​of a series of symbols decoded by the correlation operator 71b during the implementation of the receiving operation are obtained as control information c2 and output to the control unit 90.

[0116] The control unit 90 is composed of a microprocessor (MCU), and is started up when the start signal EN is supplied from the receiving unit 71, and generates a transmission and reception schedule of various signals based on the detection time t2 supplied from the receiving unit 71. Then, the following processes are performed: a process of generating a control signal SWC based on the generated transmission and reception schedule and supplying it to the switching unit 76; a process of controlling the receiving unit 71 in a manner of receiving a command signal; and a process of controlling the sending unit 75 based on the control information c2 supplied from the receiving unit 71.

[0117] The control of the transmission unit 75 by the control unit 90 includes: determining the type of signal to be transmitted to the sensor controller 31 based on the received command signal (described later). Fig.10 and when a data signal indicating data is sent, the data indicated to be sent by the control information c2 is obtained and supplied to the sending unit 75. The data supplied to the sending unit 75 includes: a unique ID of the stylus pen 2 stored in a memory not shown, data indicating the on / off state of the switch 22, data indicating the pen pressure detected by the pen pressure detection sensor 23, and the like.

[0118] In addition, when the control unit 90 causes the transmission unit 75 to transmit a data signal, the control unit 90 performs the following processing: determining whether the state of the stylus pen 2 is a contact state or a hovering state, and controlling the bit rate according to the determination result. Specifically, when the determination result is a contact state, the transmission unit 75 is caused to transmit at least a portion of the data of the transmission object at a first bit rate, and when the determination result is a hovering state, the transmission unit 75 is caused to transmit at least a portion of the data of the transmission object at a second bit rate that is smaller than the first bit rate. This will be described in detail later.

[0119] The transmitter 75 is a circuit that generates a signal to be transmitted to the sensor controller 31 and supplies it to the electrode 21, and is composed of the modulation unit 73 and the booster circuit 74. The transmitter 75 transmits the signal including the data to be transmitted by the electrode 21 by supplying the transmission signal to the electrode 21 in this way.

[0120] The modulation unit 73 is a circuit that generates a carrier signal (e.g., a rectangular wave signal) of a specified frequency or a frequency controlled by the control unit 90, and outputs it directly or modulates it based on the control of the control unit 90 and then outputs it. When sending a long burst signal and a burst signal, the modulation unit 73 does not modulate the carrier signal and outputs it directly, or modulates and outputs it in a pattern of known values ​​shared with the sensor controller 31. Thus, the long burst signal before boosting and the burst signal before boosting are output from the modulation unit 73. On the other hand, when sending a data signal, the carrier signal is modulated (OOK, PSK, etc.) using the data supplied from the control unit 90, and the modulated signal obtained as a result is output. Thus, the data signal before boosting is output from the modulation unit 73.

[0121] The booster circuit 74 generates a long burst signal, a burst signal, and a data signal by boosting the output signal of the modulator 73 to a certain amplitude. The long burst signal, the burst signal, and the data signal generated by the booster circuit 74 are sent from the electrode 21 to the space via the switch 76 .

[0122] Above, refer to Figure 1 to Figure 8 The configuration and operation overview of the stylus pen 2 and the sensor controller 31 of this embodiment have been described. Figure 9~Figure 19 The characteristic parts of the present invention in the operations of the stylus pen 2 and the sensor controller 31 will be described in detail.

[0123] first, Fig. 91 is a flowchart showing the overall processing performed by the sensor controller 31. However, this figure only shows the processing when the stylus pen 2 is in the hovering state. As shown in this figure, the sensor controller 31 is configured to repeatedly perform the same operation every time Tr defined by the inverse of the display refresh rate of the display panel configured together with the sensor 30 (for example, the inverse of 60 Hz, that is, 16.67 ms).

[0124] In each cycle, the sensor controller 31 first determines whether or not the stylus pen 2 is requested to transmit a unique ID (step S1 ). This request is made by transmitting a command signal indicating an instruction to transmit a unique ID.

[0125] If the sensor controller 31 determines that no request is made in step S1, it performs the stylus pen detection process (step S2a) and the finger touch detection process (steps S3 and S4) alternately four times each. Each stylus pen detection process is performed at a time Ts (which is the same as the time Ts). Figure 4~Figure 6 The detection of finger F is the same as the time Ts shown. For example, 2500μs), and each finger touch detection process is continuously executed within time Tf (for example, 1500μs). It should be noted that the detection of finger F is performed as a single finger touch position detection unit by performing two finger touch detection processes (steps S3 and S4) that are performed discontinuously with the stylus detection process between them.

[0126] On the other hand, if the sensor controller 31 determines that a request has been made in step S1, it will only repeatedly execute the stylus pen detection process (step S2b) four times. In this case, each stylus pen detection process is continuously executed within the time Ts+Tf. Since the finger touch detection process is no longer possible, the touch pen detection process cannot be performed during this period. Figure 1 (a) shows input using finger F. The reason why the input using finger F is limited and the duration of the stylus pen detection process is prolonged is that the size of the unique ID is large, and a long time is required to send the entire unique ID from the stylus pen 2 to the sensor controller 31. It should be noted that the unique ID can be sent once each time the pen is put down, and it can be considered that the user will hardly input using finger F at the same time as the stylus pen 2 is put down. Moreover, since the limit time is only the time Tr (for example, 16.67ms), it can be considered that the limit of the input using finger F for sending the unique ID will hardly affect the user's experience.

[0127] Hereinafter, a period with time Ts+Tf as one period is referred to as a "frame", and a period with time Tr as one period (operation period of display processing of the display panel) is referred to as a "superframe". That is, the stylus pen 2 of this embodiment is configured to transmit downlink signals in units of superframes, and also transmit downlink signals in units of frames. Fig. 9In the example of , one super frame includes 4 frames, but the number of frames in one super frame is not limited to 4. In addition, a "frame" and a "super frame" including a plurality of frames may be respectively changed to a "packet" and a "frame" including a transmission of a plurality of packets.

[0128] Fig.10 is a diagram showing the format of a downlink signal transmitted by the stylus pen 2 during the stylus pen detection process executed by the sensor controller 31. As described above, the downlink signal includes a long burst signal, a burst signal, and a data signal. Fig.10 , five types of data (A) to (E) are shown regarding the data transmitted by the data signal. It should be noted that, for simplicity, the term "transmission data" is sometimes used below to refer to the transmission of the data signal.

[0129] exist Fig.10 The data (D) (E) depicted with hatching on the lower right is data sent when the stylus pen 2 is in contact, and is sent by the stylus pen 2 at a first bit rate. On the other hand, the data (B) (C) is data sent when the stylus pen 2 is in a hovering state, and is sent by the stylus pen 2 at a second bit rate that is lower than the first bit rate. In addition, the data (A) is data sent regardless of whether the stylus pen 2 is in a hovering state or in contact, and is sent by the stylus pen 2 at a second bit rate. The present invention has a main feature in that the bit rates of the data (A) to (E) are controlled in this way.

[0130] Below, refer to Fig.10 The operations of the sensor controller 31 and the stylus pen 2 will be described in detail with reference to a processing flowchart showing the respective processes of the sensor controller 31 and the stylus pen 2 .

[0131] Fig.11 2 is a flowchart showing the processing of receiving an uplink signal and transmitting a downlink signal by the stylus pen 2. Fig.11 ,right Figure 8 The operation of each part of the stylus pen 2 (particularly the receiving part 71 , the transmitting part 75 , and the control part 90 ) will be described in detail.

[0132] First, although not shown, the control unit 90 of the stylus pen 2 stores a state flag indicating its own state. The state indicated by the state flag includes a sensor controller non-detection state (=0) and a sensor controller detected state (=1). The control unit 90 controls the transmission unit 75 so as to transmit a signal in units of frames by referring to the state flag at the start timing of the above-mentioned frame (step S70).

[0133] When the state flag referred to in step S70 is "0", the receiving unit 71 of the stylus pen 2 first enters the receiving operation dormant state (step S71). Then, after a predetermined time has passed, the detection of the detection mode c1 described above is attempted (step S72). The dormant period of step S71 is provided in order to reduce the power consumption of the stylus pen 2 by intermittently performing the detection operation of the detection mode c1.

[0134] Next, the receiving unit 71 determines whether the detection pattern c1 is detected by the attempt in step S72 (step S73). As a result, if it is determined that the detection pattern c1 is not detected, the process returns to step S70. On the other hand, if it is determined that the detection pattern c1 is detected, the receiving unit 71 issues a Figure 8 The control unit 90 is started by the start signal EN shown in FIG. 1 , and the detection operation of the symbols constituting the detection mode c1 and the segmentation mode STP is continued until the segmentation mode STP is detected (step S74). When the segmentation mode STP is detected, the receiving unit 71 sets the detection time t2 ( Figure 8 ) is output to the control unit 90. The control unit 90 that has received the detection time t2 performs a process (specifically, the above-mentioned process of generating a transmission and reception schedule) for synchronization with the sensor controller 31 based on the detection time t2 (step S75), and then sets the status flag to "1" (step S76), and returns the process to step S70.

[0135] When the state flag referred to in step S70 is "1", the control unit 90 first performs a detection operation of the command signal (step S80). Specifically, the detection operation receives the control information c2 ( Figure 8 Reference) supply action, in Figure 4~Figure 6 Next, the control unit 90 determines whether the command signal is detected by the detection operation of step S80 (step S81). If it is determined that the command signal is not detected, the state flag is set to "0" (step S82), and the process returns to step S70. This step S82 is, for example, when the stylus pen 2 is separated from the touch pen 2. Figure 1 This is a process performed when the stylus pen 2 cannot detect the uplink signal due to reasons other than the uplink detection height AH shown.

[0136] On the other hand, when it is determined in step S81 that a command signal is detected, the control unit 90 determines the content of the detected command signal (content of the instruction from the sensor controller 31) (step S83). Specifically, the content of the command signal includes a transmission instruction (LB) of a long burst signal, a transmission instruction (ID) of a unique ID, and a transmission instruction (DT) of data other than the unique ID.

[0137] If it is determined in step S83 that the content of the command signal is a transmission instruction (LB) for a long burst signal, the control unit 90 causes the transmission unit 75 to transmit the long burst signal (step S84). More specifically, Fig.10 As shown in (1), after receiving the command signal transmitted in the time T0 between time t0 and time t1, the control unit 90 controls the transmission unit 75 so as to transmit the long burst signal in the time T1 between time t1 and time t5. Figure 4 As described above, T1=Ts-T0. The control unit 90 then Fig.11 The process returns to step S70 as shown.

[0138] If it is determined in step S83 that the content of the command signal is a unique ID transmission instruction (ID), the control unit 90 first determines whether the stylus pen 2 is in a hovering state (step S85). This determination is made by confirming that Figure 8 That is, the control unit 90 determines that the state is hovering when the pen pressure detected by the pen pressure detection sensor 23 is zero, and determines that the state is not hovering (contact state) when the pen pressure detected by the pen pressure detection sensor 23 is greater than zero.

[0139] When it is determined in step S85 that the state is the hovering state, the control unit 90 causes the transmission unit 75 to first transmit a burst signal (step S86 ), and then continuously transmits data (A) and data (B) using the second transmission method (steps S87 and S88 ).

[0140] like Fig.10 As shown in (2), data (A) is data composed of a burst signal, a predetermined start flag Start, and state information State composed of 1 bit of information indicating the determination result of step S85 (hover state or contact state). In this case, the state information State is information indicating the hover state. The control unit 90 performs the following operation at a time T4 (refer to Figure 3 ) and then, in the period until time t3, the transmission unit 75 is controlled by using the second transmission method to sequentially transmit the start mark Start and the state information State. The second transmission method is a method of transmitting each bit using the second bit rate described above, and the second time (for example, 90 μ seconds) longer than the first time (for example, 30 μ seconds) using the first transmission method described later is spent on the transmission of each bit. A gap time of a predetermined time length is set between the burst signal and the start mark Start.

[0141] like Fig.10As shown in (2), data (B) is composed of mode information Mode, frame number FN, part of the unique ID, and checksum CS. The control unit 90 controls the transmission unit 75 to transmit these information in the above order using the second transmission method that is the same as that of data (A) from the time t3 when the transmission of the state information State ends to the time t7 when the frame ends. As a result, the time required from the start of receiving the command signal to the end of transmitting the data (B) becomes Ts+Tf, which cannot be changed. Fig. 9 The time required for finger touch detection shown is too short to detect the finger touch. Therefore, the sensor controller 31 in this case cannot detect the finger touch.

[0142] The components of data (B) are described in detail. First, mode information Mode is 1-bit information indicating the type of data to be transmitted next (unique ID or other data). In data (B), the type indicated by mode information Mode is "unique ID".

[0143] The frame number FN is 2-bit information indicating the order of frames in a super frame, and indicates the frame number of the currently executed stylus pen detection process in one super frame.

[0144] The unique ID is 52 bits of information that is different for each stylus 2. 52 bits of information is very large for information sent by the stylus 2 and cannot be sent in one frame, so it is divided into each frame in one super frame and sent. Specifically, it is divided into 13 bits and sent in four frames in one super frame. The frame number FN is used to restore the unique ID sent in this way at the sensor controller 31.

[0145] The inversion bit Op is arranged in the middle of and after the unique ID. The inversion bit Op is a bit obtained by inverting the last bit among a predetermined number of bits, and the control unit 90 controls the transmission unit 75 so that the inversion bit Op is transmitted after the predetermined number of bits. Fig.10 In the example of (2), one inversion bit Op is arranged after the 6-bit unique ID, and then one inversion bit Op is arranged after the 7-bit unique ID. The inversion bit Op is provided to prevent the same bit from being repeated for more than a predetermined number of times.

[0146] The checksum CS is an error detection code calculated based on the data (e.g., a 13-bit unique ID) included in the same data (B). The number of bits in the checksum CS is arbitrary, but Fig.10 The control unit 90 calculates the checksum CS when generating data (B), for example, and places it at the end of data (B). The sensor controller 31 also calculates the checksum CS after receiving the unique ID, and determines whether the unique ID is received normally by comparing it with the received checksum CS.

[0147] return Fig.11 When it is determined in step S85 that the state is in contact, the control unit 90 causes the transmission unit 75 to first transmit a burst signal (step S89 ), then transmit data (A) using the second transmission method (step S90 ), and then transmit data (D) using the first transmission method (step S91 ).

[0148] The content of data (A) is as described above. However, the state information State in this case is information indicating the contact state.

[0149] like Fig.10 As shown in (5), data (D) is a signal composed of mode information Mode, frame number FN, part of the unique ID, and checksum CS. In this case, the category represented by mode information Mode is "unique ID". In addition, in data (D), inversion bits Op are configured at three locations, one at the beginning of data (D) and two locations in the middle of the unique ID (more specifically, after the 3-bit unique ID and after the 6-bit unique ID).

[0150] The number of bits of the unique ID transmitted by one data (D) is 12 bits. In this case, the checksum CS is, for example, a 3-bit error detection code calculated based on the 12-bit unique ID contained in the same data (D). The unique ID is divided and transmitted in four frames in one super frame, similarly to the case of data (B). However, since the total number of bits of the unique ID is 52 bits as described above, there will be a shortage of 4 bits per frame if 12 bits are used. The 4-bit unique ID is transmitted as a sequence number SN in the data (E) described later.

[0151] The control unit 90 controls the transmission unit 75 in a manner that transmits each information constituting the data (D) in the above-mentioned order using the first transmission method during the period from time t3 after the transmission of the state information State ends to time t6. The first transmission method is a method of transmitting each bit using the above-mentioned first bit rate, and it takes, for example, 30 μ seconds to transmit each bit. This time length of 30 μ seconds is 1 / 3 of the value of the above-mentioned second transmission method. In addition, time t6 is a time slightly later than time t5 at which the stylus detection processing ends in the case of transmitting a long burst signal (a time earlier than time t7 at which the frame ends), and the time T3 (= t6 - t1) required for transmitting the burst signal, data (A) and data (D) becomes a value slightly longer than time T1 required for transmitting the long burst signal. Thus, Fig. 9 Although part of the time for finger touch detection is used for transmission and reception of data (D), the encroachment on the time for finger touch detection is extremely small. In this case, the sensor controller 31 can perform finger touch detection.

[0152] return Fig.11 If it is determined in step S83 that the content of the command signal is a transmission instruction (DT) for data other than the unique ID, the control unit 90 first determines whether the stylus pen 2 is in a hovering state (step S92). The details of the determination in step S92 are the same as those in step S85, so the detailed description is omitted.

[0153] When it is determined in step S92 that the state is the hovering state, the control unit 90 causes the transmission unit 75 to first transmit a burst signal (step S93 ), and then continuously transmits data (A) and data (C) using the second transmission method (steps S94 and S95 ).

[0154] The content of data (A) is as described above. However, the state information State in this case is information indicating a hovering state.

[0155] Data (C) is as follows Fig.10 (3) includes the signal of mode information Mode, two switch information SW1, SW2, and battery information Bat, or Fig.10 (4) is a signal including only the mode information Mode. In this case, the category indicated by the mode information Mode is "other data". In addition, the first switch information SW1 indicates Figure 8 1-bit information (first digital value) of the on / off state of the switch 22 shown. Fig.10 As can be understood from the description of (3), the state information State is arranged before the switch information SW1 in one frame. The second switch information SW2 is information that is reserved in this embodiment and is not actually used. The battery information Bat is a 1-bit information indicating the remaining amount of the driving battery (not shown) of the stylus pen 2. The battery information Bat is configured to indicate the remaining amount of the battery by using the frequency of becoming "1" in multiple transmissions.

[0156] The control unit 90 causes the transmission unit 75 to transmit the first frame and the third frame in one super frame. Fig.10 (3) The data (C) shown in FIG. 1 is transmitted by the transmission unit 75 in the second frame and the fourth frame in one super frame. Fig.10 Data (C) shown in (4) The reason for changing the transmission content in each frame is that it is not necessary to transmit the switch information SW1 and SW2 and the battery information Bat at a high rate, and priority is given to reducing the power consumption of the stylus pen 2 .

[0157] about Fig.10(3) The control unit 90 controls the transmission unit 75 to transmit the information constituting the data (C) in the above-mentioned order using the second transmission method from the time t3 after the transmission of the state information State is completed to the time t5. Therefore, the time required for the transmission of the burst signal, the data (A) and the data (C) becomes T1 which is the same as the time required for the transmission of the long burst signal. On the other hand, regarding Fig.10 (4) shows data (C), and during the period from time t3 after the transmission of the state information State ends to time t4 (a time between time t3 and time t5), the transmission unit 75 is controlled so that the mode information Mode constituting the data (C) is transmitted using the second transmission method. In the latter case, during the period from time t4 to time t5, the control unit 90 enters the sleep state, and the power consumption of the stylus pen 2 is reduced accordingly.

[0158] return Fig.11 When it is determined in step S92 that the state is in contact, the control unit 90 causes the transmission unit 75 to first transmit a burst signal (step S97 ), then transmit data (A) using the second transmission method (step S98 ), and then transmit data (E) using the first transmission method (step S99 ).

[0159] The content of data (A) is as described above. However, the state information State in this case is information indicating the contact state.

[0160] like Fig.10 As shown in (6), data (E) is a signal composed of mode information Mode, frame number FN, sequence number SN, reservation information RS, pen pressure data P, switch information SW1, and checksum CS. In this case, the category represented by mode information Mode is "other data". In addition, in data (E), inversion bits Op are arranged at three locations, namely, one at the beginning of data (E), one after reservation information RS, and one after pen pressure data P.

[0161] As described above, the serial number SN is 4 bits of information out of the 52 bits constituting the inherent ID, and is used by the sensor controller 31 to identify multiple styluses 2 being used with the same sensor controller 31. It should be noted that the serial number SN can also be information for determining the pen tip setting category, which indicates the setting state of the pen tip of the stylus 2 (pencil, brush, etc.). The serial number SN is similar to the inherent ID, and is transmitted in segments of 1 bit each in 4 frames within 1 super frame. The sensor controller 31 stores the 48 bits received by data (D), and obtains the entire inherent ID by combining it with the 4 bits received by data (E).

[0162] The reservation information RS is information that can be freely set by the seller of the stylus pen 2 , and two digits are reserved.

[0163] The pen pressure data P is 12-bit data (second digital value) representing the pen pressure detected by the pen pressure detection sensor 23, and is configured by dividing 6 bits into each of two consecutive frames (more specifically, the first and second frames or the third and fourth frames configured in one super frame).

[0164] The control unit 90 controls the transmission unit 75 to transmit each information constituting the data (E) in the above-mentioned order using the first transmission method during the period from time t3 when the transmission of the state information State is completed to time t6. Fig. 9 A portion of the time for finger touch detection shown is used for transmitting and receiving data (E). However, as in the case of data (D), the encroachment on the time for finger touch detection is extremely small, so the sensor controller 31 can perform finger touch detection.

[0165] As described above, the control unit 90 causes the sending unit 75 to selectively send data (A) to (E) according to the instruction of the sensor controller 31. At this time, the bit rate of the stylus 2 is also controlled according to the state (contact state or hovering state). Specifically, the bit rate (the second bit rate mentioned above) of the data (B) (C) sent in the hovering state is made smaller than the bit rate (the first bit rate mentioned above) of the data (D) (E) sent in the contact state. In addition, the control unit 90 causes the sending unit 75 to send the data (A) at the second bit rate, similarly to the data (B) (C) sent in the hovering state. It should be noted that Fig.10 An example is shown in which the ratio of the first bit rate to the second bit rate is 3:1, but the ratio can be changed appropriately. The control unit 90 performs such bit rate control in order to improve the noise tolerance in the hovering state where the S / N ratio of the downlink signal is easily deteriorated, and in particular, with respect to data (A), in order to enable the sensor controller 31 to reliably receive the state information State. This will be summarized and described in detail later.

[0166] then, Fig.12 and Fig.13 FIG. 1 is a flowchart showing the processing of transmitting an uplink signal and receiving a downlink signal by the sensor controller 31. Fig.12 and Fig.13 , for Fig.11 The processing of the sensor controller 31 corresponding to the processing of the stylus pen 2 shown will be described.

[0167] The sensor controller 31 stores a status flag indicating its own status similarly to the stylus pen 2. The status indicated by the status flag includes a stylus pen not detected and a pen start signal transmission waiting state (=0), a stylus pen not detected and a response waiting state to a pen start signal (=1), a stylus pen detected and a position not derived state (=2), a stylus pen position derived and a unique ID not received state (=3), and a unique ID received state (=4). The sensor controller 31 first refers to the status flag (step S10).

[0168] If the status flag referred to in step S10 is "0", the sensor controller 31 Fig. 9 The pen start signal is sent within the time Ts shown in the figure (step S11). Specifically, the detection mode c1 is repeated and the segmentation mode STP is sent. The sensor controller 31 that has completed the continuous sending of the pen start signal Fig. 9 After the finger touch detection process is performed within the time Tf shown (step S12), the status flag is set to "1" (step S13), and the process returns to step S10. Fig.12 In the example, step S13 is performed after step S12, but they may be performed in parallel. This relationship is also the same for other finger touch detection processes (steps S16, S23, S41, S54, S61) and subsequent processes (for example, the processes of steps S17 to S20 for step S16).

[0169] When the status flag referenced in step S10 is "1", the sensor controller 31 first sends a command signal indicating a transmission instruction of a long burst signal (LB request) (step S14). The transmission of various command signals including this command signal requires the above-mentioned time T0. After that, the sensor controller 31 performs the above-mentioned time T1. Fig.10 The receiving operation of the long burst signal shown in FIG. 1 is performed (step S15). Figure 7 (a) The first half of the full range scan is performed.

[0170] After the sensor controller 31 has finished receiving the long burst signal after the time T1, it performs finger touch detection processing within the time Tf (step S16) and determines whether the long burst signal is received (step S17). As a result, if it is determined that the long burst signal is not received, the status flag is set to "0" (step S18), and the process returns to step S10. This step S18 is, for example, when the stylus pen 2 is in Figure 1The processing is performed when the sensor controller 31 cannot receive the downlink signal due to reasons such as being outside the sensing range SR shown in FIG. 1. On the other hand, when it is determined in step S17 that the downlink signal is received, the sensor controller 31 sets the status flag to "2" (step S19), determines a further instruction to be sent to the stylus pen 2 (step S20), and then returns the processing to step S10. The instruction determined here is a transmission instruction (LB) of a long burst signal.

[0171] If the status flag referenced in step S10 is "2", the sensor controller 31 first re-transmits a command signal indicating a transmission instruction (LB request) for a long burst signal (step S21). Thereafter, the sensor controller 31 re-executes a reception operation for a long burst signal within time T1 (step S22). This reception operation is performed by referring to Figure 7 (b) The second half of the full range scan described above is performed. It should be noted that when the first half of the full range scan (step S15) and the second half of the full range scan (step S22) can be performed within one time T1, these two steps S15 and S22 may be performed in one process.

[0172] After the sensor controller 31 has finished receiving the long burst signal after the time T1, it performs finger touch detection processing within the time Tf (step S23) and determines whether the long burst signal is received (step S24). As a result, if it is determined that the long burst signal is not received, the status flag is set to "0" (step S25), and the process returns to step S10. Step S25 is, for example, when the stylus pen 2 is separated from the touch screen. Figure 1 The processing is performed when the sensor controller 31 cannot receive the downlink signal due to reasons such as being outside the sensing range SR shown in FIG. 2. On the other hand, when it is determined in step S24 that the signal is received, the sensor controller 31 sets the status flag to "3" (step S26), and derives the position of the stylus pen 2 based on the detection result of the long burst signal in step S15 and the detection result of the long burst signal in step S22 (step S27). Then, after determining the next command to be sent to the stylus pen 2 (step S28), the processing returns to step S10. The command determined here is a transmission instruction of a unique ID (ID request), and also plays the role of a transmission instruction of a normal burst signal that is not a long burst signal. The fact that the command also plays the role of a transmission instruction of a burst signal is also the same for the command sent in step S50 described later (a command indicating a transmission instruction (DT request) of data other than a unique ID).

[0173] When the state flag referred to in step S10 is "3", the sensor controller 31 transmits a command signal indicating the command determined in step S28 or steps S37 and S45 described later (step S30). Thereafter, the sensor controller 31 sequentially performs the reception operation of the burst signal and the data (A) (steps S31a and S31b), and when receiving the burst signal, derives the position coordinates of the stylus pen 2 based on the detection intensity of the received burst signal at each linear electrode 30X and 30Y.

[0174] The burst signal receiving operation in step S31a is performed by referring to Figure 7 (c) is performed. On the other hand, the reception operation of data (A) in step S31b is performed using one linear electrode 30X or linear electrode 30Y selected based on the position coordinates derived from the detection strength of the burst signal. In addition, the sensor controller 31 obtains data (A) by demodulating the received signal using the first demodulation method corresponding to the second bit rate described above. These points are also the same when the burst signal and data (A) are detected in steps S51a and S51b described later.

[0175] After the sensor controller 31 completes the receiving operation of the burst signal and data (A), it then determines whether the stylus pen 2 is in the hovering state by confirming the state information State contained in the data (A) (step S32). And, if it is determined to be in the hovering state, it performs the receiving operation of data (B) (step S33). It should be noted that, as shown in FIG. Fig.10 As described above, since the transmission of the data (B) is continued until the end time of the frame, the sensor controller 31 in this case does not perform the detection process of the finger touch.

[0176] The receiving operation of step S33 is similar to the receiving operation of data (A), and is performed using one linear electrode 30X or linear electrode 30Y selected based on the position coordinates derived in step S31. This is also the same for the receiving operation of data (C) to (E) described later (steps S40, S53, S60). In this way, the detection period of the data signal can be fully utilized, so more data can be sent from the sensor controller 31 to the stylus 2. In addition, the sensor controller 31 obtains data (B) by demodulating the received signal using the first demodulation method described above. This is also the same for the receiving operation of data (C) described later (step S53).

[0177] After the sensor controller 31 completes the data (B) reception operation, it determines whether the burst signal, data (A) or data (B) is received (step S34). If it is determined that none of them are received, the status flag is set to "0" (step S35), and the process returns to step S10. Step S35 is, for example, when the stylus pen 2 is separated from the Figure 1 The processing is performed when the sensor controller 31 cannot receive the downlink signal due to reasons such as being outside the sensing range SR shown in the figure. On the other hand, when it is determined in step S34 that any one of them has been received, it is determined whether all (i.e., 52 bits) of the fragments (13 bits of data) of the unique ID that can be obtained through data (B) have been received (step S36). And, when it is determined that it has not been obtained (there is still some remaining), the command indicating the transmission instruction (ID request) of the unique ID is determined as the next command to be sent to the stylus pen 2 (step S37), and the processing is returned to step S10. On the other hand, when it is determined in step S36 that all have been received (there is no remaining), the status flag is set to "4" (step S38), and the command indicating the transmission instruction (DT request) of data other than the unique ID is further determined as the next command to be sent to the stylus pen 2 (step S39), and the processing is returned to step S10.

[0178] Although not shown, the sensor controller 31 performs processing to restore and store the unique ID by combining the received multiple fragments of the unique ID in parallel with the execution of steps S38 and S39. In this case, the sensor controller 31 determines the order of combination based on the frame number FN sent together with each fragment.

[0179] If the sensor controller 31 determines in step S32 that the state is not hovering (is in contact), it performs a data (D) receiving operation (step S40). Fig.13 As shown in the figure, the receiving operation is performed in a form that slightly intrudes into the time originally reserved for finger touch detection, but the sensor controller 31 uses the remaining time after the end of step S40 to perform the finger touch detection process (step S41). The sensor controller 31 demodulates the received signal using the second demodulation method corresponding to the first bit rate described above to obtain data (D). This is also the same for the receiving operation (step S60) of data (E) described later. The second demodulation method is a demodulation method with a higher bit error rate than the first demodulation method.

[0180] After the sensor controller 31 completes the data (D) reception operation, it determines whether a burst signal, data (A), or data (D) is received (step S42). If it is determined that none of them are received, the status flag is set to "0" (step S43), and the process returns to step S10. Step S43 is, for example, when the stylus pen 2 is separated from the Figure 1 The processing is performed when the sensor controller 31 cannot receive the downlink signal due to reasons such as being outside the sensing range SR shown in the figure. On the other hand, when it is determined in step S42 that any one of them is received, the sensor controller 31 determines whether all (i.e., 48 bits) of the fragments (12 bits of data) of the unique ID that can be obtained through the data (D) are received (step S44). And, when it is determined that it has not been obtained (there is still some remaining), the command indicating the transmission instruction (ID request) of the unique ID is determined as the next command to be sent to the stylus pen 2 (step S45), and the processing is returned to step S10. On the other hand, when it is determined in step S44 that all are received (there is no remaining), the status flag is set to "4" (step S46), and the command indicating the transmission instruction (DT request) of data other than the unique ID is further determined as the next command to be sent to the stylus pen 2 (step S47), and the processing is returned to step S10.

[0181] When the state flag referred to in step S10 is "4", the sensor controller 31 transmits a command signal indicating the command determined in step S39, S47 or steps S57, S64 described later (step S50). Thereafter, the sensor controller 31 sequentially performs the receiving operation of the burst signal and the data (A) (steps S51a, S51b), and when receiving the burst signal, derives the position coordinates of the stylus pen 2 based on the detection intensity of the received burst signal at each linear electrode 30X, 30Y.

[0182] After the sensor controller 31 completes the reception of the burst signal and data (A), it then checks the state information State included in the data (A) to determine whether the stylus pen 2 is in the hovering state (step S52). If it is determined to be in the hovering state, it receives data (C) (step S53).

[0183] After the sensor controller 31 completes the receiving operation of data (C), it performs finger touch detection processing within time Tf (step S54), and determines whether a burst signal, data (A) or data (C) is received (step S55). As a result, if it is determined that none of them are received, the status flag is set to "0" (step S56), and the process returns to step S10. Step S56 is, for example, when the stylus pen 2 is separated from the touch screen. Figure 1On the other hand, if it is determined in step S55 that any one of them is received, the command indicating the transmission instruction (DT request) of data other than the unique ID is determined as the next command to be transmitted to the stylus pen 2 (step S57), and the processing is returned to step S10.

[0184] If the sensor controller 31 determines in step S52 that the state is not hovering (is in contact), it performs a receiving operation of data (E) (step S60). Fig.13 As shown, the process is performed in a manner that slightly intrudes into the time originally reserved for finger touch detection, but the sensor controller 31 performs the finger touch detection process (step S61 ) using the remaining time after the end of step S60 .

[0185] After the sensor controller 31 completes the data (E) reception operation, it determines whether a burst signal, data (A), or data (E) is received (step S62). If it is determined that none of them are received, the status flag is set to "0" (step S63), and the process returns to step S10. Step S63 is, for example, when the stylus pen 2 is separated from the Figure 1 On the other hand, if it is determined in step S62 that any one of them is received, the command indicating the transmission instruction (DT request) of data other than the unique ID is determined as the next command to be transmitted to the stylus pen 2 (step S64), and the processing is returned to step S10.

[0186] Here, although not shown in the figure, the sensor controller 31 determines whether all the fragments (1-bit data) of the serial number SN that can be obtained through the data (E) are received in parallel with the execution of step S64. And, in the case where it is determined that all are received, the inherent ID is restored and stored by combining the multiple fragments of the received serial number SN with the multiple fragments of the inherent ID received in the repeatedly executed step S40. In this case, the sensor controller 31 determines the order of their combination based on the frame number FN sent together with each fragment of the serial number SN, and determines the order of their combination based on the frame number FN sent together with each fragment of the inherent ID. The position of the serial number SN in the inherent ID is determined in advance according to the specifications.

[0187] The method of restoring such information is the same for the pen pressure data P. That is, as described above, the stylus pen 2 divides the pen pressure data P into a plurality of frames for transmission, but the sensor controller 31 can determine the order of combining the plurality of received pen pressure data P fragments based on the frame number FN received together with each fragment of the pen pressure data P.

[0188] The above, for Fig.11 Next, for a specific method for the control unit 90 of the stylus pen 2 to make the bit rate (second bit rate) of the data (B) (C) and the data (A) transmitted in the hovering state smaller than the bit rate (first bit rate) of the data (D) (E) transmitted in the contact state, refer to Figure 14~Figure 19 Provide detailed explanation.

[0189] Fig.14 1 is a diagram showing a first example of a method for transmitting data (A) to (C) and data (D) and (E) respectively by stylus pen 2. The transmitting unit 75 of stylus pen 2 in this example is configured to modulate a carrier signal using the data of the transmission object using the same modulation method regardless of the state of stylus pen 2. Specifically, the carrier signal is modulated using the data of the transmission object using amplitude modulation (including on-off modulation) or phase modulation of a carrier signal of a fixed frequency. Furthermore, the control unit 90 modulates the modulation rate (the number of modulations per unit time) of data (D) and (E) in a manner that is greater than the modulation rate of data (A) to (C) (in Fig.14 In the example, the ratio is 4:1) to control the transmission unit 75. As a result, the bit rate (first bit rate) of data (D) (E) is greater than the bit rate (second bit rate) of data (A) to (C), so that, for example, communication with Fig.10 The switch information SW1 is different from the pen pressure data P and other large information data, and is related to the first digital value ( Fig.10 Compared with when the switch information SW1 (such as the switch information SW1) is sent in the contact state, it is possible to reduce the demodulation error and the bit value judgment error rate at the sensor controller 31. The change of the modulation rate can also be achieved by making the transmission time of the amplitude modulation or phase modulation using the switch information SW1 longer than the hovering time in the contact state.

[0190] Fig.15FIG. 0 is a diagram showing a second example of the respective transmission methods of data (A) to (C) and data (D) and (E) performed by the stylus 2. In this example, the control unit 90 controls the transmission unit 75 such that each bit of the data to be transmitted is transmitted only once in data (D) and (E) and repeatedly transmitted four times in data (A) to (C). This control can be a control that makes the data more redundant (for error correction) in the hovering state as an encoding method, or a control that reduces the modulation rate in the hovering state as in Fig.14 Thus, from the viewpoint of the amount of data actually transmitted, the bit rate (first bit rate) of data (D) and (E) is higher than the bit rate (second bit rate) of data (A) to (C). Therefore, even in this example, it is possible to transmit a large amount of information such as pen pressure data P different from the switch information SW1 in the contact state, and the determination error rate at the sensor controller 31 can be reduced compared to the case where the first digital value ( Fig.10 such as the switch information SW1) transmitted in the hovering state is transmitted in the contact state.

[0191] Note that, as an encoding process that makes the data redundant for error correction, if the hovering state is larger than the contact state, the ratio may not be N:1 (N is an integer of 2 or more). For example, the same information may be repeated M times (M is an integer of 2 or more) when in contact, and the same information may be repeated N times (N > M) when in the hovering state.

[0192] Fig.16 FIG. 11 is a diagram showing a third example of the respective transmission methods of data (A) to (C) and data (D) and (E) performed by the stylus 2. In this example, the control unit 90 controls the transmission unit 75 to append a checksum CS (first error detection code) to the end of the data signal. And, when transmitting data (A) to (C), the number of bits of the appended checksum CS is increased compared to the case of transmitting data (D) and (E). Specifically, for data of a size of the transmission time td amount (assumed to be n bits), a checksum CS of a size of the transmission time tc1 amount is appended to data (A) to (C), and a checksum CS of a size of the transmission time tc2 (<tc1) amount is appended to data (D) and (E). Since the bit rate is the number of bits transmitted per unit time, the bit rate (first bit rate) of data (A) to (C) in this case becomes n / (td + tc2), and the bit rate (second bit rate) of data (A) to (C) becomes n / (td + tc1). Since tc1 > tc2, the latter (= n / (td + tc1)) becomes a value smaller than the former (= n / (td + tc2)). Therefore, it can be said that even in this example, the second bit rate can be made smaller than the first bit rate.

[0193] Fig.17This is a diagram showing a fourth example of a method for transmitting data (A) to (C) and data (D) (E) respectively performed by the stylus pen 2. The stylus pen 2 of this example uses either phase modulation (specifically, BPSK) or amplitude modulation as the modulation method (second modulation method) for data (A) to (C), and on the other hand, uses amplitude phase modulation (specifically, 4QAM) as the modulation method (first modulation method) for data (D) (E). That is, different modulation methods are used for data (A) to (C) and data (D) (E), thereby making the bit rate of data (A) to (C) smaller than that of data (D) (E). The first modulation method is a modulation method having a smaller bit error rate than the second modulation method. Specifically, in Fig.17 In the example of , the ratio of the bit rate (first bit rate) of data (D) (E) to the bit rate (second bit rate) of data (A) to (C) is 2:1. Therefore, even with this example, the second bit rate can be made smaller than the first bit rate.

[0194] Fig.18 1 is a diagram showing a fifth example of a method for transmitting data (A) to (C) and data (D) and (E) respectively by stylus pen 2. Stylus pen 2 of this example, like stylus pen 2 of the fourth example, uses phase modulation (specifically, BPSK) as a modulation method for data (A) to (C), and on the other hand, uses amplitude phase modulation as a modulation method for data (D) and (E). The amplitude phase modulation of this example represents the first bit by the phase (0 degrees or 180 degrees) and represents the second bit by the amplitude (1 times or 2 times). Even in this example, as in the fourth example, the ratio of the bit rate (first bit rate) of data (D) and (E) to the bit rate (second bit rate) of data (A) to (C) is 2:1, so the second bit rate can be made smaller than the first bit rate.

[0195] Fig.19 6 is a diagram showing a sixth example of a method for transmitting data (A) to (C) and data (D) and (E) respectively by the stylus pen 2. This example relates to a case where the sensor controller 31 transmits a command signal and the stylus pen 2 transmits a downlink signal during a blank period when the display panel configured together with the linear electrodes 30X and 30Y is not driven. Fig.19 (a) shows the frame Frame_1 corresponding to the first blank period. Fig.19 (b) shows a frame Frame_2 corresponding to the second blanking period following the first blanking period. In each figure, the circled number 1 corresponds to data (B) (C), and the circled number 2 corresponds to data (D) (E).

[0196] In this example, the stylus pen 2 uses two frames, Frame_1 and Frame_2, to send 14 bits of information when sending data (D) (E). More specifically, in frame Frame_1, 1-bit data data1 to data6 are sent after 2-bit information that serves as status information indicating whether the stylus pen 2 is in a hovering state or a contact state, and 1-bit data data7 to data14 are sent in frame Frame_2. It should be noted that the 2-bit information that is the initial status information configured in frame Frame_1 is specifically "01" or "10", and is configured in a manner that allows the sensor controller 31 to distinguish between data (D) (E) and data (B) (C).

[0197] On the other hand, when sending data (B) and (C), the stylus pen 2 uses two frames, Frame_1 and Frame_2, to send 2 bits of information. More specifically, in frame Frame_1, the first bit of information ("0" or "1") is sent 8 times in succession, and in frame Frame_2, the second bit of information ("0" or "1") is sent 8 times in succession.

[0198] That is, the stylus pen 2 in this example sends each bit of the target data only once in data (D) (E), and repeatedly sends it eight times in data (B) (C). This is the same as the example except that the number of repetitions is different. Fig.15 The stylus pen 2 of the second example shown is the same. Therefore, also in this example, the second bit rate can be made smaller than the first bit rate.

[0199] As described above, according to the stylus pen 2 of this embodiment, the bit rate (second bit rate) of the data (B) (C) transmitted in the hovering state can be made smaller than the bit rate (first bit rate) of the data (D) (E) transmitted in the contact state. Therefore, the noise tolerance in the hovering state, in which the S / N ratio of the downlink signal is easily deteriorated, is improved, so that the non-detection rate of the downlink signal, the bit error detection rate when demodulating or decoding the downlink signal, and the decoding error rate based on error correction can be reduced. Therefore, even if the downlink signal is transmitted with the same transmission strength as in the contact state, the possibility of receiving the downlink signal in the hovering state can be reduced.

[0200] In addition, data (A) is sent at the same low bit rate as data (B) and (C) regardless of the state of the stylus pen 2, so the sensor controller 31 can reliably receive the state information State regardless of the state of the stylus pen 2. Therefore, the receiving operation (the first or second demodulation method described above) of the sensor controller 31 can be reliably changed in accordance with the bit rate of the downlink signal, so that data (B) to (E) can be reliably sent from the stylus pen 2 to the sensor controller 31.

[0201] Moreover, if Fig.10 As shown, since each frame has a frame number FN, when the stylus pen 2 divides large-size data such as the inherent ID and pen pressure data P into multiple frames for transmission, even if the divided information is not received in sequence, the sensor controller 31 on the receiving side can properly restore the information based on the frame number FN.

[0202] Although preferred embodiments of the present invention have been described above, the present invention is not limited to such embodiments at all, and the present invention can of course be implemented in various forms within the scope not departing from the gist of the present invention.

[0203] For example, in the above embodiment, a burst signal and data (A) are transmitted before any one of data (B) to (E), but for example, transmission of the burst signal and data (A) before data (D) or (E) may be omitted.

[0204] In addition, in the above-mentioned embodiment, it is described that the stylus pen 2 sends the state information State in all frames, but in the case of sending more than two frames continuously, the initial frame of the two or more frames may include the state information State, and the state information State may not be sent in the subsequent frames continuous with the initial frame. More specifically, in frames other than the initial frame sent in the super frame, it may be set not to send the state information State (omit sending). In this case, the sensor controller 31 stores the state information State received in the initial frame, and applies the state information State to the subsequent frames. It should be noted that such omission of sending the state information State is preferably performed only when the state of the stylus pen 2 is in contact state.

[0205] In addition, although not specifically mentioned in the above embodiment, Fig.11 The state of the stylus pen 2 when it is determined to be in contact state in step S85 is called "unique ID transmission mode". Fig.11The state of the stylus pen 2 when it is determined to be in the contact state in step S90 is called the "serial number transmission mode". In this case, the control unit 90 of the stylus pen 2 controls the transmission unit 75 to transmit the part of the unique ID of the stylus pen 2 except the serial number using data (D) in the super frame corresponding to the unique ID transmission mode, and controls the transmission unit 75 to transmit the serial number SN using data (E) in the super frame corresponding to the serial number transmission mode.

[0206] In addition, in the above-mentioned embodiment, the stylus pen 2 determines the content of the command signal sent from the sensor controller 31, thereby determining whether the command is an instruction to send the unique ID (ID) or an instruction to send data other than the unique ID (DT), and switches whether to send the unique ID or send data other than the unique ID according to the result, but the determination may also be made by the stylus pen 2 according to its own state (for example, the operation state of the switch SW1). For example, the unique ID may be sent when the switch SW1 is not operated (that is, when the user does not touch the operation part (switch SW1, switch SW2, etc.) of the stylus pen 2 at all), and the data other than the unique ID (information of the switch SW1, etc.) may be sent when the switch SW1 is operated (that is, it is ON). In this way, the transmission of the unique ID with a relatively large amount of information can be completed in the non-operation state. In addition, the unique ID sent in the hovering state may include the information of the serial number SN sent in the contact state.

[0207] In addition, the sensor controller 31 may also attach a checksum (second error detection code) corresponding to the data when transmitting an uplink signal including arbitrary data (third digital value) such as a command. In this case, the stylus pen 2 preferably uses the checksum to determine whether the data transmitted by the sensor controller 31 is correctly received, but the long burst signal, the burst signal, and the data (A) to (E) may be transmitted regardless of the result of the determination (even if the result of the determination is NG).

[0208] Hereinafter, first and second modified examples of the above-described embodiment will be described.

[0209] Fig. 20This is a diagram showing the structure of the stylus pen 2 of the first variant of the above-mentioned embodiment. The sensor controller 31 and the stylus pen 2 of this variant are different from the above-mentioned embodiment in that they use wireless communication that does not utilize the electrostatic coupling method when sending uplink signals. In addition, the stylus pen 2 is also different from the above-mentioned embodiment in that it corresponds to the transmission of two downlink signals DS1 and DS2 that are different in the form of carrier signals. Both downlink signals DS1 and DS2 are configured to be able to transmit the above-mentioned long burst signals, burst signals, and data (A) to (E), and the stylus pen 2 uses them separately depending on the type of sensor controller 31 that is approaching. Below, refer to Fig. 20 The structure of the stylus pen 2 according to this modification will be described in detail.

[0210] like Fig. 20 As shown, the stylus pen 2 of this modification example includes an electrode 21 , a signal processing unit 24 , a power supply 25 , an amplifier 26 , and a receiver 27 .

[0211] The receiving unit 27 is a functional unit configured to be able to perform communication based on, for example, Bluetooth (registered trademark) as wireless communication. In the present modification, the sensor controller 31 receives an uplink signal transmitted using Bluetooth (registered trademark).

[0212] The signal processing unit 24 is a functional unit having a function of selectively transmitting two types of downlink signals DS1 and DS2 and a function of receiving an uplink signal US via the receiving unit 27 , and specifically includes a control unit 91 , a boost unit 92 , an oscillation unit 93 , and a switch unit 94 .

[0213] The voltage booster 92 has a function of generating a DC voltage V1 by boosting a DC voltage supplied from the power source 25. In a specific example, the voltage booster 92 is formed of a DC-DC converter or a charge pump circuit.

[0214] The oscillating unit 93 has a function of generating a non-modulated sinusoidal wave signal (carrier signal) vibrating at a predetermined frequency by performing an oscillating operation based on the DC voltage supplied from the power supply 25. The amplifying unit 26 has a function of generating a non-modulated sinusoidal wave signal v2 by amplifying the sinusoidal wave signal generated by the oscillating unit 93 at a predetermined amplification factor. Fig. 20 As shown, the amplifier 26 is preferably formed by an amplifier circuit, and the amplifier circuit is formed by a transformer and a capacitor.

[0215] The switch section 94 is a 1-circuit 3-contact switch element having a terminal a connected to the output end of the boost section 92 , a terminal b connected to the output end of the amplifier 26 , a terminal g connected to a power supply wiring supplied with a ground potential, and a common terminal c connected to the electrode 21 .

[0216] The control unit 91 is an IC that supplies a control signal Ctrl for controlling the switch unit 94 and controls the receiving unit 27 to receive the uplink signal sent by the sensor controller 31, and is configured to operate using the power supplied from the power supply 25. In a specific example, the control unit 91 may be an ASIC or an MCU. The control unit 91 determines whether to send the uplink signal based on the content of the uplink signal received via the receiving unit 27 or the fact that the uplink signal is not received (the sensor controller 31 only corresponds to the case of one-way communication from the stylus pen 2 to the sensor controller 31). Fig.10 The type of downlink signal (downlink signal DS1 or downlink signal DS2) used for the long burst signal, burst signal and data (A) to (E) shown in the figure. Figure 8 The control unit 90 shown similarly determines the transmission and reception schedule of various signals and the like, and controls the switch unit 94 based on the determined transmission and reception schedule.

[0217] When the downlink signal DS1 is transmitted, the control unit 91 controls the switch unit 94 so as to function as a first switch unit provided between the output end of the boost unit 92 and the electrode 21. That is, the switch unit 94 is switched between a state in which the terminal a is connected to the common terminal c and a state in which the terminal g is connected to the common terminal c. The state in which the terminal a is connected to the common terminal c corresponds to a state in which the first switch unit is turned on, and the state in which the terminal g is connected to the common terminal c corresponds to a state in which the first switch unit is turned off.

[0218] When a burst signal or a long burst signal is transmitted using the downlink signal DS1, the control unit 91 periodically performs switching control of the switch unit 94 at a predetermined period. When the terminal a is connected to the common terminal c, the DC voltage V1 becomes the output voltage of the switch unit 94. On the other hand, when the terminal g is connected to the common terminal c, the ground potential becomes the output voltage of the switch unit 94. Therefore, a burst signal without modulation is output from the switch unit 94, which becomes a long burst signal or a burst signal.

[0219] On the other hand, when the downlink signal DS1 is used to transmit the data signal, the control unit 91 generates a burst signal based on data modulation, i.e., a data signal, by performing switching control of the switch unit 94 based on data such as the unique ID, the pen pressure data P, and the switch information SW indicating the on / off state of a switch (not shown) provided in the stylus pen 2. As a specific method of modulating the burst signal by the control unit 91, on / off modulation, frequency modulation, etc. can be considered.

[0220] When the downlink signal DS2 is transmitted, the control unit 91 controls the switch unit 94 so as to function as a second switch unit provided between the output end of the amplifier 26 and the electrode 21. That is, the switch unit 94 is switched between a state in which the terminal b is connected to the common terminal c and a state in which the terminal g is connected to the common terminal c. The state in which the terminal b is connected to the common terminal c corresponds to a state in which the second switch unit is turned on, and the state in which the terminal g is connected to the common terminal c corresponds to a state in which the second switch unit is turned off.

[0221] When a burst signal or a long burst signal is transmitted using the downlink signal DS2, the control unit 91 fixes the switch unit 94 to the terminal b. Therefore, the switch unit 94 outputs a non-modulated sinusoidal wave signal v2, which becomes a long burst signal or a burst signal.

[0222] On the other hand, when the downlink signal DS2 is used to transmit the data signal, the control unit 91 generates a data signal based on a sine wave signal modulated by the data by switching the switch unit 94 based on the unique ID, the pen pressure data P, the switch information SW, etc. As a specific method of modulating the sine wave signal by the control unit 91, on-off modulation is adopted.

[0223] As described above, according to this modification, Bluetooth (registered trademark) can be used in the transmission and reception of uplink signals. It should be noted that although an example of using Bluetooth (registered trademark) is described here, short-range wireless communication other than Bluetooth (registered trademark) can also be used for the transmission and reception of uplink signals.

[0224] Furthermore, according to the present modification, the stylus pen 2 can communicate bidirectionally or unidirectionally with a plurality of sensor controllers 31 of different types by using the downlink signals DS1 and DS2 separately.

[0225] Fig.21 2 is a processing flow chart showing the operation of the stylus pen 2 according to the second variant of the above-mentioned embodiment. The stylus pen 2 of this variant is different from the above-mentioned embodiment in that it determines its own state based on the reception strength of the uplink signal instead of the writing pressure detected by the writing pressure detection sensor 23. Fig.21 , the operation of the stylus pen 2 of this variation will be described in detail, centering on the differences from the above-mentioned embodiment.

[0226] The stylus pen 2 of this modification replaces Fig.10 The determinations of steps S100 and S101 are performed respectively based on the determinations of steps S85 and S92 shown in the figure. Both steps S100 and S101 are steps for determining the reception strength of the command signal detected in the previous step S80.

[0227] When it is determined in step S100 that the reception strength is lower than the specified value (i.e., "weak"), the stylus pen 2 determines its own state to be in the hovering state. Then, as in the case where it is determined in step S85 to be in the hovering state, a burst signal and data (A) (B) are transmitted (steps S86 to S88). On the other hand, when it is determined in step S100 that the reception strength is higher than the specified value (i.e., "strong"), the stylus pen 2 determines its own state to be in the contact state. Then, as in the case where it is determined in the contact state in step S85, a burst signal and data (A) (D) are transmitted (steps S89 to S91).

[0228] In addition, when it is determined in step S101 that the reception strength is lower than the specified value (i.e., "weak"), the stylus pen 2 determines its own state to be the hovering state. Then, as in the case where it is determined in step S92 to be the hovering state, a burst signal and data (A) (C) are transmitted (steps S93 to S95). On the other hand, when it is determined in step S101 that the reception strength is greater than the specified value (i.e., "strong"), the stylus pen 2 determines its own state to be the contact state. Then, as in the case where it is determined in step S92 to be the contact state, a burst signal and data (A) (E) are transmitted (steps S97 to S99).

[0229] As described above, according to the stylus pen 2 of this modification, the state of the stylus pen 2 can be determined based on the reception strength of the command signal regardless of the writing pressure. Therefore, for example, the present invention can also be applied to a stylus pen 2 that does not have a writing pressure detection function.

[0230] It should be noted that, in this modification, an example is described in which the stylus pen 2 determines its own state based on the reception strength of the uplink signal (specifically, the command signal), but the sensor controller 31 may also determine the state of the stylus pen 2 based on the reception strength of the downlink signal in the sensor controller 31, and notify the result to the stylus pen 2. In this case, it is preferred that the sensor controller 31 includes state information indicating the state of the stylus pen 2 as part of the command signal, and the stylus pen 2 obtains its own state by receiving and decoding the state information.

[0231] Description of symbols

[0232] 2 Stylus

[0233] 3 Electronic devices

[0234] 20 Core

[0235] 21 Electrode

[0236] 22, 44x, 44y, 62 switch

[0237] 23 Pen pressure detection sensor

[0238] 24 Signal Processing Unit

[0239] 25 Power Supply

[0240] 26 Amplification

[0241] 27, 50, 71 Receiving Department

[0242] 30 Sensors

[0243] 30X, 30Y Linear Electrode

[0244] 31 Sensor Controller

[0245] 40 Selection Department

[0246] 41x, 41y conductor selection circuit

[0247] 51 Amplifier circuit

[0248] 52 Detection circuit

[0249] 53 Converter

[0250] 60, 75 Sending Department

[0251] 61 Mode Supply Department

[0252] 63 Diffusion Processing Unit

[0253] 64 Code string holding unit

[0254] 65 Send Protection Department

[0255] 70 Logic Department

[0256] 71a Waveform regeneration unit

[0257] 71b Correlation operator

[0258] 73 Modulation Department

[0259] 74 Boost Circuit

[0260] 76 Switching Department

[0261] 90, 91 Control Department

[0262] 92 booster

[0263] 93 Oscillation unit

[0264] 94 Switch

[0265] FN Frame Number

[0266] Mode mode information

[0267] Op Invert bit

[0268] P Pen pressure data

[0269] RS Appointment Information

[0270] SN Serial Number

[0271] Start sign

[0272] State Status Information

[0273] SW, SW1, SW2 switch information.

Claims

1. A touch pen, comprising: Core; An electrode, disposed near the core; and a controller coupled to the electrode and configured to Determine the status signal, generating a downlink signal using one of a first modulation process and a second modulation process different from the first modulation process, wherein the first modulation process and the second modulation process are configured to modulate a carrier signal of a defined frequency with binary data of a defined number of bits, arranging the state signal indicating which of the first modulation process or the second modulation process is used to generate the downlink signal in the downlink signal at a position before a position where the binary data is arranged along the time axis, and The downlink signal is transmitted through the electrodes.

2. The stylus pen according to claim 1, wherein: The state signal changes a value of the state signal according to whether the stylus is in a contact state in which the stylus is in contact with the sensor panel or in a hovering state in which the stylus is not in contact with the sensor panel.

3. The stylus pen according to claim 2, wherein: The state signal is generated by modulating state data indicating whether the stylus pen is in a contact state or a hovering state.

4. The stylus pen according to claim 3, wherein: The status data is a 1-bit value.

5. The stylus pen according to claim 1, wherein: The controller is operable to place at least one of an unmodulated burst signal and a start bit at a position before a position along a time axis where the status signal is placed.

6. The stylus pen according to claim 1, wherein: The first modulation process and the second modulation process differ in a time period required to transmit the binary data.

7. The stylus pen according to claim 6, wherein: The controller is operable to use a first modulation process associated with transmitting the binary data for a longer period of time than the second modulation process.

8. The stylus pen according to claim 1, wherein: The controller is in operation, detecting an uplink signal sent from a sensor panel, and The status signal is determined based on the uplink signal.

9. The stylus pen according to claim 8, wherein: The controller is in operation, determining whether the stylus is in a contact state in which the stylus is in contact with the sensor panel or in a hovering state in which the stylus is not in contact with the sensor panel based on the strength of the uplink signal transmitted from the sensor panel, and The state signal is determined according to whether the stylus pen is in a contact state or a hovering state.

10. The stylus pen according to claim 1, wherein: The controller is in operation, determining whether the stylus is in a contact state in which the stylus is in contact with a sensor panel or in a hovering state in which the stylus is not in contact with the sensor panel based on pressure applied to a tip of the stylus, and The state signal is determined according to whether the stylus pen is in a contact state or a hovering state.

11. The stylus pen according to claim 1, wherein: The first modulation process and the second modulation process have different bit rates.

12. The stylus pen according to claim 1, wherein: The first modulation process and the second modulation process have different modulation rates.

13. The stylus pen according to claim 1, wherein: The first modulation process and the second modulation process have different bit error rates.

14. The stylus pen according to claim 13, wherein: The first modulation process is an N-level modulation process, where N is an integer of 3 or more, and the second modulation process is an M-level modulation process, where M is an integer of 2 or more and M <N。 15. A controller configured to control the operation of a stylus pen, the stylus pen comprising a core and an electrode disposed near the core, the controller comprising: a modulator configured to determine a status signal and to generate a downlink signal using one of a first modulation process and a second modulation process different from the first modulation process, wherein the first modulation process and the second modulation process are configured to modulate a carrier signal of a defined frequency with binary data of a defined number of bits, and A transmitter coupled to the modulator and configured to arrange the status signal indicating which of the first modulation process or the second modulation process is used to generate the downlink signal in the downlink signal at a position before the position where the binary data is arranged along the time axis, and to transmit the downlink signal through the electrode.

16. A sensor controller comprising: a memory including computer executable instructions, and one or more processors configured to execute the computer-executable instructions and configured to: Receives downlink signal from stylus, determining, based on a state signal arranged in the downlink signal at a position before a position where the binary data of a defined number of bits is arranged along the time axis, which of a first modulation process and a second modulation process different from the first modulation process is used by the stylus pen to modulate a carrier signal of a defined frequency using the binary data to generate the downlink signal, and The binary data is decoded using the first modulation process or the second modulation process indicated by the status signal.

17. The sensor controller according to claim 16, wherein: The one or more processors are configured to execute the computer executable instructions to: An uplink signal is sent from a sensor panel coupled to the sensor controller.

18. The sensor controller according to claim 16, wherein: The one or more processors are configured to execute the computer executable instructions to: The downlink signal is received from the stylus in response to the uplink signal.

19. The sensor controller according to claim 16, wherein: The state signal changes a value of the state signal according to whether the stylus is in a contact state in which the stylus is in contact with a sensor panel coupled to the sensor controller or in a hovering state in which the stylus is not in contact with the sensor panel.

20. The sensor controller according to claim 16, wherein: The first modulation process and the second modulation process differ in at least one of a time period required to transmit the binary data, a bit rate, a modulation rate, and a bit error rate.

21. A sensor controller connected to an electrode group disposed on a panel, using charges induced in the electrode group to detect the position of a stylus pen, wherein: determining whether the touch pen is in an undetected state in which the touch pen is not detected or in a detected state in which the touch pen is detected, In the undetected state, the electrode group disposed on the panel is used to send a first command signal to the stylus pen. In the detected state, a second command signal different from the first command signal is sent using a number of electrodes less than the number of the electrode group, The position of the stylus is derived based on a downlink signal sent from the stylus that detected the first command signal or the second command signal.

22. The sensor controller according to claim 21, The first instruction signal is a signal indicating a transmission instruction of a long burst signal. The second command signal is a signal indicating an instruction to transmit data.

23. The sensor controller according to claim 21 or 22, The electrodes whose number is smaller than the number of the electrode group are electrodes near the position of the stylus pen.

24. A system comprising: stylus; and The sensor controller is connected to the electrode group disposed on the panel and detects the position of the stylus pen using the charge induced in the electrode group. in, the sensor controller, determining whether the touch pen is in an undetected state in which the touch pen is not detected or in a detected state in which the touch pen is detected, In the undetected state, the electrode group disposed on the panel is used to send a first command signal to the stylus pen. In the detected state, a second command signal different from the first command signal is sent using a number of electrodes less than the number of the electrode group, The position of the stylus is derived based on a downlink signal sent from the stylus that detected the first command signal or the second command signal.

25. A method, which is a method performed in a system, the system comprising: Stylus; and The sensor controller is connected to the electrode group disposed on the panel and detects the position of the stylus pen using the charge induced in the electrode group. in, The method comprises the following steps: The sensor controller determines whether the sensor controller is in an undetected state in which the stylus pen is not detected or in a detected state in which the stylus pen is detected; When the sensor controller is in the non-detection state, the sensor controller uses the electrode group disposed on the panel to send a first command signal to the stylus pen; The sensor controller, when in the detected state, uses a smaller number of electrodes than the number of the electrode group to send a second command signal different from the first command signal; and The sensor controller derives a position of the stylus based on a downlink signal sent from the stylus that detects the first command signal or the second command signal.

26. A stylus pen, By wireless communication not via the touch surface, an uplink signal transmitted by the sensor controller is received, determining a type of a downlink signal received by the sensor controller via the touch surface based on the content of the uplink signal or the fact that the uplink signal was not received, Sending a downlink signal of the determined type, Determine whether the pen tip is in a contact state with the operating surface or in a hovering state without contact, and if the result of the determination is that the pen tip is in the contact state, send the downlink signal; if the result of the determination is that the pen tip is in the hovering state, include an error detection code with a longer number of bits than that in the contact state in the downlink signal and send it.

27. A stylus pen, By wireless communication not via the touch surface, an uplink signal transmitted by the sensor controller is received, determining a type of a downlink signal received by the sensor controller via the touch surface based on the content of the uplink signal or the fact that the uplink signal was not received, Sending a downlink signal of the determined type, The downlink signal is configured to be transmitted in units of super frames of a period specified by the uplink signal, The super frame includes a specified number of frames, A frame number indicating the order of the frames in the super frame is transmitted in each of the predetermined number of frames.

28. The stylus pen according to claim 27, The super frame is a period corresponding to a display cycle of a display device configured together with a sensor used by the sensor controller in order to receive the downlink signal.

Images