Sensor controller and stylus

Abstract

The invention relates to a sensor controller and a stylus. The present invention prevents an old stylus that supports only an old protocol from becoming unable to be used in a new position detection device that supports a new protocol. A position detection device (3) is configured so as to be capable of operating in a detection mode in which multiple protocols are transmitted and uplink signals SMA-US are activated at the same time. A multi-protocol simultaneous activation uplink signal SMA-US is formed by adding subsequent data for activating a stylus (2) in a second protocol different from a first protocol to a first half configured to enable activation of the stylus (2) in the first protocol.

Description

Technical Field

[0001] The invention relates to a sensor controller and a touch pen. Background Art

[0002] The position detection device is a device that implements pen input by detecting the position of the stylus pen within the touch surface. The detection of the position of the stylus pen is performed by the stylus pen and the sensor controller built into the position detection device performing two-way communication via the sensor arranged within the touch surface. Hereinafter, the signal sent from the sensor controller to the stylus pen in the two-way communication is referred to as an "uplink signal", and the signal sent from the stylus pen to the sensor controller is referred to as a "downlink signal".

[0003] Patent document 1 discloses a technique for making the time length of an uplink signal variable in a system for bidirectional communication between a stylus pen and a sensor controller. In this technique, in order to realize an uplink signal with a variable time length, a length field indicating the size of a command included in the uplink signal is configured in the uplink signal (the length field in Patent document 1). Figure 3 ) or a flag indicating whether there is subsequent data (Patent Document 1 Fig. 9 ).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 6603435 Summary of the invention

[0007] Problems to be solved by the invention

[0008] The protocol defining the specific steps of the bidirectional communication may be changed due to the emergence of new technology, etc. In such a change, it is necessary to prevent an old stylus pen supporting only the old protocol from being unusable in a new position detection device supporting the new protocol.

[0009] Therefore, one of the objects of the present invention is to provide a position detection device and a stylus pen that can prevent an old stylus pen that supports only an old protocol from becoming unusable in a new position detection device that supports a new protocol.

[0010] As a specific technology for configuring a position detection device that can be used even with an old stylus, it can be considered to enable communication through both the new protocol and the old protocol by, for example, alternately sending an uplink signal based on a new protocol and an uplink signal based on an old protocol. However, in this case, the sending frequency of the uplink signal under each protocol will become 1 / 2, and thus the search efficiency of the stylus will be deteriorated.

[0011] Therefore, another object of the present invention is to provide a position detection device and a stylus that can prevent a decrease in the search efficiency of the stylus and prevent an old stylus that only supports an old protocol from becoming unusable in a new position detection device that supports a new protocol.

[0012] Furthermore, when a stylus pen supporting a new protocol is used in a new position detection device supporting a new protocol, it is preferable to enable bidirectional communication to be started using the new protocol instead of the old protocol.

[0013] Therefore, another object of the present invention is to provide a stylus pen that can start bidirectional communication with a new protocol instead of an old protocol when the stylus pen supporting the new protocol is used in a new position detection device supporting the new protocol.

[0014] Means for solving problems

[0015] The position detection device on the first side of the present invention operates in a detection mode of sending a multi-protocol simultaneously activated uplink signal, and the multi-protocol simultaneously activated uplink signal is formed by adding subsequent data for activating the stylus with a second protocol different from the first protocol to a front half that is configured to activate the stylus with a first protocol.

[0016] The stylus pen of the first aspect of the present invention includes: a first determination unit, which determines whether a first uplink signal capable of activating the stylus pen with a first protocol is included in a received signal; a second determination unit, which determines whether first subsequent data for activating the stylus pen with a second protocol different from the first protocol is attached to the first uplink signal when the first determination unit determines that the first uplink signal is included in the received signal; and a sending unit, which sends a downlink signal using the second protocol when the second determination unit determines that the first subsequent data is attached to the first uplink signal.

[0017] The position detection device of the second aspect of the present invention sends a first uplink signal configured to activate the stylus pen using a first protocol different from the second protocol within a reserved time set in a frame represented by the sending of a second uplink signal configured to activate the stylus pen using a second protocol in a frame format.

[0018] The stylus pen of the third aspect of the present invention stores setting information representing either a first protocol or a second protocol that are different from each other, and when receiving an uplink signal for activating the stylus pen with the protocol of one of the first and second protocols represented by the setting information, sends a downlink signal based on the protocol of the one party; on the other hand, when receiving an uplink signal for activating the stylus pen with the protocol of the other party that is not the protocol of the one party represented by the setting information, does not send a downlink signal based on the protocol of the other party.

[0019] Effects of the Invention

[0020] According to the first aspect of the present invention, by using a multi-protocol simultaneous activation uplink signal sent by a position detection device that supports both the first protocol and the second protocol, it is not necessary to mention a stylus that supports both the first protocol and the second protocol, and it is also possible to activate a stylus that only supports the first protocol, thereby preventing an old stylus that only supports the first protocol from becoming unable to be used in a new position detection device that supports the second protocol. In addition, since the multi-protocol simultaneous activation uplink signal can be used to activate both a stylus that only supports the first protocol and a stylus that supports both the first protocol and the second protocol, a decrease in the search efficiency of the stylus can also be prevented.

[0021] According to the second aspect of the present invention, since the first uplink signal is sent within the reserved time set in the frame represented by the second uplink signal, it is possible to prevent the search efficiency of the stylus pen from decreasing while preventing an old stylus that only supports the first protocol from becoming unusable in a new position detection device that supports the second protocol.

[0022] According to the third aspect of the present invention, since the protocol for sending downlink signals can be limited to one type, when a stylus pen supporting a new protocol is used in a new position detection device supporting a new protocol, two-way communication can be started with the new protocol instead of the old protocol. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a diagram showing the configuration of a position detection system 1 according to the first embodiment of the present invention.

[0024] Figure 2 1 is a diagram showing the internal structure of the stylus pens 21 and 22 according to the first embodiment of the present invention.

[0025] Figure 3 1 is a diagram showing a configuration example of a multi-protocol simultaneous activation uplink signal SMA-US according to the first embodiment of the present invention.

[0026] Figure 4The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timing of each signal (when neither of the stylus pens 21 and 22 is present near the panel surface 3 a ) according to the first embodiment of the present invention.

[0027] Figure 5 The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when the stylus pen 21 is close to the panel surface 3 a ) according to the first embodiment of the present invention.

[0028] Figure 6 The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when the stylus pen 22 is close to the panel surface 3 a ) according to the first embodiment of the present invention.

[0029] Figure 7 The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when the stylus pen 22 is away from the panel surface 3 a ) according to the first embodiment of the present invention.

[0030] Figure 8 The diagram shows the operation modes of the conventional sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when the stylus pen 22 is close to the panel surface 3 a ) according to the first embodiment of the present invention.

[0031] Fig. 9 The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when the stylus pen 22 approaches the panel surface 3 a ) according to the first modified example of the first embodiment of the present invention.

[0032] Fig.10 The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when both the stylus pens 21 and 22 are not present near the panel surface 3 a ) according to the second modification of the first embodiment of the present invention.

[0033] Fig.11 The diagram shows the operation modes of the sensor controller 31 and the stylus pens 21 and 22 and the transmission and reception timings of each signal (when neither of the stylus pens 21 and 22 is present near the panel surface 3 a ) according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0035] Figure 1is a diagram showing the structure of the position detection system 1 of the present embodiment. As shown in the figure, the position detection system 1 is configured to include two types of stylus 21 and 22 and a position detection device 3. The position detection device 3 includes a panel surface 3a (touch surface), a sensor 30 arranged directly below the panel surface 3a, a sensor controller 31, a host processor 32, and a wireless communication unit 33.

[0036] Each of the stylus pens 21 and 22 is a pen-shaped device having a function of bidirectionally communicating with the sensor controller 31 via the sensor 30. In the following description, it is assumed that the bidirectional communication is performed by an active electrostatic method, but the present invention can also be applied to cases where bidirectional communication is performed by other methods such as an electromagnetic induction method.

[0037] The difference between the stylus 21 and 22 is that they use different specific protocols for the two-way communication. The stylus 21 only supports the relatively old first protocol, while the stylus 22 supports the relatively new second protocol in addition to the first protocol. Hereinafter, when there is no need to distinguish between the stylus 21 and 22, the stylus 21 and 22 are sometimes collectively referred to as "stylus 2".

[0038] The position detection device 3 is a computer that supports input (pen input) using the stylus pen 2 , such as a personal computer such as a smartphone, a tablet terminal, or a notebook computer. The panel surface 3 a may also serve as a display surface of a display, in which case the display is arranged overlapping the sensor 30 .

[0039] If the various structures in the position detection device 3 are specifically described, first, the sensor 30 is a device used for the above-mentioned two-way communication between the sensor controller 31 and the stylus pen 2, and is configured to have a sensor electrode group arranged in the panel surface 3a. Specifically, the sensor electrode group is configured to include a plurality of X electrodes extending in the y direction in the panel surface 3a and arranged side by side at equal intervals in the x direction, and a plurality of Y electrodes extending in the x direction in the panel surface 3a and arranged side by side at equal intervals in the y direction. The plurality of X electrodes and the plurality of Y electrodes are independently connected to the sensor controller 31. One of the plurality of X electrodes and the plurality of Y electrodes can be used as a common electrode in the display, and the position detection device 3 in this case is called an "In-Cell type". On the other hand, the plurality of X electrodes and the plurality of Y electrodes may not be used as a common electrode in the display, and the position detection device 3 in this case is called an "On-Cell type" or "Out-Cell type".

[0040] When the tip electrode 21 (described later) disposed at the tip of the stylus pen 2 approaches the sensor electrode group constituting the sensor 30, capacitive coupling is generated between them. In the active electrostatic capacitance method, bidirectional communication between the stylus pen 2 and the sensor controller 31 is achieved via this capacitive coupling. Hereinafter, the signal sent from the sensor controller 31 to the stylus pen 2 via this capacitive coupling is referred to as an "uplink signal US", and the signal sent from the stylus pen 2 to the sensor controller 31 via this capacitive coupling is referred to as a "downlink signal DS".

[0041] The uplink signal US is a signal including a command (instruction) from the sensor controller 31 to the stylus pen 2 , and also has a role of notifying the stylus pen 2 of the transmission timing of the downlink signal DS.

[0042] The downlink signal DS is a signal including a position signal for the sensor controller 31 to detect the position of the stylus pen 2 within the panel surface 3a (hereinafter referred to as "pen position") and a data signal modulated by data (hereinafter referred to as "pen data") transmitted to the sensor controller 31. The pen data may include, in addition to a response to a command in the uplink signal US, a pen pressure value described later, switch information indicating the on / off state of a switch provided on the surface of the stylus pen 2, identification information of the stylus pen 2, and the like.

[0043] Figure 1 The uplink signals US1 and US2 (first and second uplink signals) shown in FIG. 1 represent uplink signals US transmitted by the first protocol and the second protocol, respectively. Figure 1 The downlink signals DS1 and DS2 (first and second downlink signals) shown represent downlink signals DS sent by the first protocol and the second protocol, respectively. In the uplink signal US sent by the sensor controller 31, in addition to them, a multi-protocol simultaneous activation uplink signal SMA-US is also included, but this will be described in detail later.

[0044] Here, the relationship between the first protocol and the second protocol is typically the difference in versions of the same communication standard (for example, active electrostatic method). The specific differences can be various, but sometimes there are differences in the uplink signal US and the downlink signal DS. For example, the specific differences between the first protocol and the second protocol may appear in the reception timing of the downlink signal DS, the frequency of the carrier signal of the downlink signal DS, the modulation method of the data signal contained in the downlink signal DS, the method of the spread spectrum code used to send the data signal contained in the downlink signal DS, the format of the data signal contained in the downlink signal DS, and the time slot used by the stylus 2 to send the downlink signal DS. It should be noted that in the first protocol and the second protocol, the communication methods such as active modulation method and electromagnetic induction method may be different.

[0045] In this embodiment, the first protocol is a frameless protocol and the second protocol is a framed protocol. However, this is just an example, and the first protocol may be a framed protocol and the second protocol may be a frameless protocol.

[0046] The frameless method is a method in which the stylus pen 2 transmits the downlink signal DS without leaving an interval after receiving the uplink signal US. When communicating in the frameless method, the sensor controller 31 periodically transmits the uplink signal US. In addition, the stylus pen 2 continuously receives the uplink signal US, and immediately transmits the downlink signal DS when receiving the uplink signal US.

[0047] On the other hand, the frame mode is a mode in which the sensor controller 31 sets a frame including multiple time slots. When communicating in the frame mode, the sensor controller 31 sends the uplink signal US at the beginning of the frame. In addition, the stylus pen 2 continuously performs the reception action of the uplink signal US in the initial state, and obtains the time position of the frame and each time slot set therein through the reception timing of the received uplink signal US. Then, each time slot is used to send the downlink signal DS. It is also possible to specify the time slot used by the stylus pen 2 for sending the downlink signal DS from the sensor controller 31. In this case, the stylus pen 2 uses the specified time slot to send the downlink signal DS. Once the stylus pen 2 receives the uplink signal US, it only performs the reception action of the uplink signal US at the beginning of the frame.

[0048] Returning to the description of each structure in the position detection device 3. The sensor controller 31 is an integrated circuit that realizes various functions by executing a program installed as hardware or a program stored in a built-in memory. The functions of the sensor controller 31 include a function of deriving the pen position and acquiring pen data by performing the above-mentioned two-way communication with the stylus pen 2 and a function of sequentially supplying a report including the derived pen position and acquired pen data to the host processor 32.

[0049] In this embodiment, the description will be continued assuming that the sensor controller 31 supports both the first protocol and the second protocol. In this case, the sensor controller 31 is configured to be able to operate in a detection mode for detecting the stylus pen 2, a first communication mode for performing bidirectional communication with the stylus pen 2 via the sensor 30 using the first protocol, and a second communication mode for performing bidirectional communication with the stylus pen 2 via the sensor 30 using the second protocol. Hereinafter, when there is no need to particularly distinguish between the first communication mode and the second communication mode, they are sometimes collectively referred to as "communication mode".

[0050] The sensor controller 31 is configured to send a multi-protocol simultaneous activation uplink signal SMA-US at the beginning of a frame set according to the second protocol in the detection mode. Furthermore, the sensor controller 31 is configured to enter either the first communication mode or the second communication mode based on the reception status of the downlink signal DS as a response to the sent multi-protocol simultaneous activation uplink signal SMAUS, and perform bidirectional communication corresponding to the entered communication mode with the stylus pen 2. Hereinafter, the sensor controller 31 entering either communication mode is sometimes referred to as "pairing with the stylus pen 2".

[0051] In addition, the sensor controller 31 is configured to be able to derive the position of the finger on the panel surface. This derivation is performed, for example, by an electrostatic capacitance method. In this case, the sensor controller 31 supplies a finger detection signal composed of pulses of the number of X electrodes to each of the multiple X electrodes in the sensor 30, and receives each of the multiple Y electrodes in the sensor 30. In addition, the sensor controller 31 is configured to calculate the correlation between the signal received by each Y electrode and the finger detection signal supplied to each X electrode, and derive the position of the finger based on the result. The sensor controller 31 is configured to perform the transmission and reception of the finger detection signal in the gap between the communication with the stylus pen 2, and to sequentially supply a report containing the position of the finger derived as a result to the host processor 32.

[0052] The host processor 32 is the central processing unit of the position detection device 3, and is configured to execute the operating system of the position detection device 3 and various applications including the drawing application by executing the program stored in the built-in memory. The series of reports supplied by the sensor controller 31 to the host processor 32 are used in the host processor 32 for processing by the operating system and the drawing application. These processes include the generation and display of digital ink, the movement of the cursor, and the detection of various gestures such as tapping and dragging.

[0053] The wireless communication unit 33 is a device for communicating with other devices including the stylus pen 2 by short-range wireless communication such as Bluetooth (registered trademark). The host processor 32 and the sensor controller 31 are configured to be able to communicate with the stylus pen 2 via the wireless communication unit 33 by short-range wireless communication.

[0054] Figure 2 2 is a diagram showing the internal structure of the stylus pen 2 (stylus pen 21, 22). As shown in the figure, the stylus pen 2 is configured to include a core 20, a pen tip electrode 21, a pressure sensor 22, a processing unit 23, a wireless communication unit 24, and a battery 25. In addition to these, the stylus pen 2 also has a switch provided on the surface, a memory storing identification information of the stylus pen 2, etc., but in Figure 2 Illustration omitted.

[0055] The core 20 is a rod-shaped member constituting the pen tip of the stylus pen 2. The pen tip electrode 21 is an electrode provided at the pen tip of the stylus pen 2, and is configured to include a pen tip 21a and a pen ring 21b. The pen tip 21a is a rod-shaped electrode provided at the front end of the core 20, and the pen ring 21b is a ring-shaped electrode provided in a manner surrounding the core 20. The stylus pen 2 is configured to receive the uplink signal US using one or both of the pen tip 21a and the pen ring 21b, and to send the downlink signal DS from the pen tip 21a and the pen ring 21b, respectively. The sensor controller 31 also performs the following processing: deriving positions based on the downlink signal DS sent from the pen tip 21a and the downlink signal DS sent from the pen ring 21b, respectively, and obtaining the position derived based on the downlink signal DS sent from the pen tip 21a as the pen position, and on the other hand, deriving the inclination (tilt angle) of the stylus pen 2 based on the derived two positions.

[0056] The pressure sensor 22 is a sensor that detects the pressure applied to the pen tip of the stylus pen 2 by detecting the force transmitted through the core 20. The value of the pressure detected by the pressure sensor 22 is supplied to the processing unit 23 as a writing pressure value.

[0057] The processing unit 23 is the central processing unit of the stylus pen 2, and performs processing to generate a downlink signal DS based on the uplink signal US received from the sensor controller 31 via the pen tip electrode 21, and transmit the downlink signal DS to the sensor controller 31 via the pen tip electrode 21. The content of the downlink signal DS generated by the processing unit 23 is as described above. The sensor controller 31 uses a plurality of X electrodes and a plurality of Y electrodes constituting the sensor 30 to receive the position signal in the downlink signal DS, respectively, approximates the distribution of the receiving intensity of the position signal in the x direction and the y direction respectively by a normal distribution curve, derives the respective peak positions, and thereby derives the pen position. In addition, the sensor controller 31 uses the X electrode or Y electrode closest to the pen position derived immediately before to receive the data signal in the downlink signal DS, demodulates it, and thereby obtains the pen data sent by the stylus pen 2.

[0058] The processing unit 23 is configured to be able to operate in a detection mode for performing detection of the sensor controller 31 and a first communication mode for performing bidirectional communication with the sensor controller 31 via the sensor 30 using a first protocol. The processing unit 23 of the stylus pen 22 is further configured to be able to operate in a second communication mode for performing bidirectional communication with the sensor controller 31 via the sensor 30 using a second protocol. The first communication mode and the second communication mode are also sometimes collectively referred to as "communication modes" when there is no need to distinguish them in particular.

[0059] The processing unit 23 entering the detection mode continuously or intermittently performs the receiving action of the uplink signal US. If the uplink signal US is received through the receiving action, the processing unit 23 enters the communication mode and starts the two-way communication with the sensor controller 31. In this way, the uplink signal US has the function of changing the action mode of the stylus pen 2 from the detection mode to the communication mode. Hereinafter, the stylus pen 2 entering any communication mode is referred to as "pairing with the position detection device 3 (or the sensor controller 31)", and the change of the stylus pen 2 from the detection mode to the communication mode is referred to as "activation". In addition, the change of the stylus pen 2 from the detection mode to the first communication mode is referred to as "activation with the first protocol", and the change of the stylus pen 2 from the detection mode to the second communication mode is referred to as "activation with the second protocol". The uplink signal US1 sent through the first protocol has the function of activating the stylus pen 2 with the first protocol. Similarly, the uplink signal US2 sent through the second protocol has the function of activating the stylus pen 2 with the second protocol.

[0060] The wireless communication unit 24 is a device for communicating with other devices including the position detection device 3 through short-range wireless communication such as Bluetooth (registered trademark). The processing unit 23 is configured to be able to communicate with the host processor 32 and the sensor controller 31 in the position detection device 3 through the wireless communication unit 33 through short-range wireless communication.

[0061] The battery 25 is a power supply device for supplying operating power to each part of the stylus pen 2. The processing unit 23 and the wireless communication unit 24 are configured to operate using the power supplied from the battery 25.

[0062] Figure 3 : is a diagram showing a structural example of a multi-protocol simultaneous activation uplink signal SMA-US. As shown in the figure, the multi-protocol simultaneous activation uplink signal SMA-US of this example is composed of 10 symbols (units of information sent using 1 spread spectrum code). The first two symbols "PRE" are preamble data used to enable the stylus 2 to detect that the received signal is the uplink signal US. The three symbols "D1", "D2" and "D3" following the two symbols "PRE" represent instructions, which represent commands to the stylus 2.

[0063] The symbol "CRC" following the symbol "D3" is a cyclic code generated based on the symbols "D1", "D2", and "D3", and serves to enable the stylus pen 2 to detect reception errors of the symbols "D1", "D2", and "D3". The three symbols "D4", "D5", and "D6" following the symbol "CRC" represent instructions in the same way as the symbols "D1", "D2", and "D3", and the instructions represent commands to the stylus pen 2. The symbol "CRC" following the symbol "D6" is a cyclic code generated based on the symbols "D4", "D5", and "D6", and serves to enable the stylus pen 2 to detect reception errors of the symbols "D4", "D5", and "D6".

[0064] The portion from the leading symbol "PRE" to the first symbol "CRC" is the first half that is configured to activate the stylus pen 2 with the first protocol, and has the same structure as the uplink signal US1. The portion from the symbol "D4" to the second symbol "CRC" is the subsequent data for activating the stylus pen 2 with the second protocol. The structure of the subsequent data is the structure in which the preamble data is removed from the uplink signal US2.

[0065] The processing unit 23 of the stylus pen 21 that does not support the second protocol is configured to determine whether the received signal supplied from the pen tip electrode 21 includes the uplink signal US1, and enter the first communication mode if it is determined to include it. Therefore, when receiving the multi-protocol simultaneous activation uplink signal SMA-US, the processing unit 23 of the stylus pen 21 determines that the uplink signal US1 is received based on only the first half thereof, and enters the first communication mode. The processing unit 23 that has entered the first communication mode performs a process of generating a downlink signal DS1 based on the received uplink signal US1 and sending it. Next, the processing unit 23 performs the receiving action of the uplink signal US1 again (specifically, the action of determining whether the uplink signal US1 is included in the received signal supplied from the pen tip electrode 21), and performs a process of generating a downlink signal DS1 based on the uplink signal US1 received as a result and sending it. The subsequent processing unit 23 repeatedly performs the same process until the uplink signal US1 is no longer received. When the state of not receiving the uplink signal US1 continues for a predetermined time, the processing unit 23 of the stylus pen 21 returns to the detection mode.

[0066] On the other hand, the processing unit 23 of the stylus pen 22 supporting both the first protocol and the second protocol determines whether the first half of the multi-protocol simultaneous activation uplink signal SMA-US (= uplink signal US1) is included in the received signal supplied from the pen tip electrode 21, and if it is determined to be included, further determines whether the above-mentioned subsequent data is attached to the detected first half. If it is determined in this determination that the subsequent data is attached, the processing unit 23 is configured to enter the second communication mode.

[0067] Here, since the second protocol is a frame-based protocol, the processing unit 23 of the stylus pen 22 obtains the time position of the frame and each time slot set therein based on the reception timing of the multi-protocol simultaneous activation of the uplink signal SMA-US, and uses each time slot to send the downlink signal DS2. Next, the processing unit 23 performs the reception operation of the uplink signal US2 at the beginning of the next frame, and performs the same processing as above when the uplink signal US2 is received. The processing unit 23 thereafter repeats the same processing until the uplink signal US2 is no longer received. When the state of not receiving the uplink signal US2 continues for a specified time, the processing unit 23 of the stylus pen 22 returns to the detection mode.

[0068] When it is determined that no subsequent data is added to the detected first half (i.e., the received uplink signal US is not the multi-protocol simultaneous activation uplink signal SMA-US but only the uplink signal US1), the processing unit 23 of the stylus pen 22 enters the first communication mode. In this case, the processing performed by the processing unit 23 is the same as the processing described for the processing unit 23 of the stylus pen 21. In this way, the processing unit 23 of the stylus pen 22 enters the first communication mode, which is a case where the sensor controller 31 does not support the second protocol.

[0069] Hereinafter, the operation of the sensor controller 31 and the stylus pens 21 and 22 according to the present embodiment will be described in more detail with reference to a transmission and reception timing chart of each signal.

[0070] Figure 4~Figure 8 The diagrams respectively show the operation modes of the sensor controller 31 and the stylus 21 and 22 and the timing of sending and receiving each signal. Figure 9~Figure 11 The frame F shown is a frame set by the sensor controller 31 according to the second protocol, and time slots TS1, TS2, and TS3 are time slots set in the frame F. In this embodiment, for simplicity, three time slots TS1, TS2, and TS3 are set in one frame F, but more time slots are actually set.

[0071] exist Figure 4 The figure shows a situation where neither the stylus 21 nor 22 exists near the panel surface 3a. In this case, the sensor controller 31 is not paired with the stylus 21 or 22 and enters the detection mode. The sensor controller 31 in this case transmits the multi-protocol simultaneous activation uplink signal SMA-US at the beginning of each frame F. In addition, after the sensor controller 31 completes the transmission of the multi-protocol simultaneous activation uplink signal SMA-US, it performs the receiving action R of the downlink signal DS and the transmitting and receiving action T of the above-mentioned finger detection signal in the same frame. Figure 4 As shown, the receiving action R is executed in each time slot, and the transmitting and receiving action T is executed in the gap between the receiving actions R.

[0072] The sensor controller 31 in the detection mode determines whether the signal received by the receiving action R is a downlink signal DS1 or DS2. This determination can be made, for example, by confirming the difference between the first protocol and the second protocol (the frequency of the carrier signal of the downlink signal DS, etc.). Figure 4 In the example, the signal received in time slot TS1 is determined to be the downlink signal DS1, and the signal received in time slots TS2 and TS3 is determined to be the downlink signal DS2. The reason for this determination will be referred to in Figure 5 and Figure 6As described later. In addition, when the data obtained by demodulating the received signal contains information about the protocol used by the stylus pen 2 in sending the downlink signal DS, the sensor controller 31 can also determine whether the received signal is the downlink signal DS1 or DS2 based on the information. The sensor controller 31 repeats the above-mentioned operation in each frame F until any one of the downlink signals DS1 and DS2 is received.

[0073] exist Figure 5 FIG. 2 shows a case where the stylus pen 21 approaches the panel surface 3a. The stylus pen 21 in the detection mode continuously performs the receiving operation R of the uplink signal US, and determines whether the received signal contains the uplink signal US1. Figure 5 In the example shown in FIG. 1 , when the received signal is the multi-protocol simultaneous activation uplink signal SMA-US, the stylus pen 21 determines that the uplink signal US1 is included in the determination. The stylus pen 21 that determines that the uplink signal US1 is included enters the first communication mode and sends the downlink signal DS1. The sending of the downlink signal DS1 is as shown in FIG. Figure 5 As shown in the figure, the stylus pen 22 is configured not to send the downlink signal DS2 in the time slot TS1 immediately after the reception of the multi-protocol simultaneous activation uplink signal SMA-US. Therefore, the sensor controller 31 can determine that it is the downlink signal DS1 by receiving the downlink signal DS in the receiving action R performed in the time slot TS1. The sensor controller 31 that determines that the downlink signal DS1 is received changes to the first communication mode, and then, while sandwiching the transmission and reception action T of the finger detection signal, it performs the transmission and reception action R of the uplink signal US1 at a predetermined period. As a result, bidirectional communication based on the first protocol is realized between the sensor controller 31 and the stylus pen 21.

[0074] exist Figure 6 FIG. 2 shows a case where the stylus pen 22 approaches the panel surface 3a. The stylus pen 22 in the detection mode continues to perform the uplink signal US reception operation R in the same manner as the stylus pen 21, and determines whether the received signal contains the uplink signal US1 (first determination unit). Figure 6In the case where the received signal is a multi-protocol simultaneous activation uplink signal SMA-US as shown in the example, the stylus 22 is determined to include the uplink signal US1 in the determination. The stylus 22 determined to include the uplink signal US1 then determines whether subsequent data (first subsequent data) for activating the stylus 2 with the second protocol is attached to the uplink signal US1 (second determination unit). In the case where the received signal is a multi-protocol simultaneous activation uplink signal SMA-US, the stylus 22 is determined to include subsequent data in the determination. The stylus 22 determined to include subsequent data enters the second communication mode, and obtains the time position of the frame F and each time slot TS1, TS2, and TS3 set therein based on the reception timing of the multi-protocol simultaneous activation uplink signal SMA-US. Then, as described above, in the time slots TS2 and TS3 other than the time slot TS1, the transmission of the downlink signal DS2 is performed (transmission unit).

[0075] If the sensor controller 31 receives the downlink signal DS2 in the receiving action R performed in the time slots TS2 and TS3, it will switch to the second communication mode from the next frame F, and then perform actions according to the second protocol. Specifically, the uplink signal US2 is sent at the beginning of each frame F, the time between each time slot TS1, TS2, and TS3 is used to sandwich the finger detection signal transmission and reception action T, and the receiving action R is performed in each time slot TS1, TS2, and TS3. In this way, bidirectional communication based on the second protocol is realized between the sensor controller 31 and the stylus pen 22.

[0076] exist Figure 7 It is shown in Figure 6 In the example of FIG. 1 , the stylus pen 22 communicating with the sensor controller 31 leaves the panel surface 3a. The figure shows a situation where the stylus pen 22 leaves the panel surface 3a after the time slot TS3 of the first frame F and the transmission and reception of the uplink signal US2 and the downlink signal DS2 become impossible.

[0077] In the communication in the second communication mode, the stylus pen 22 selects whether to continue pairing with the position detection device 3 in each frame F (pairing state selection unit). Specifically, when the uplink signal US2 is received at the beginning of each frame, the pairing with the position detection device 3 is continued, and when the uplink signal US2 is not received, the pairing with the position detection device 3 is canceled. Figure 7 In the example, the stylus pen 22 selects to release the pairing with the position detection device 3 based on not receiving the uplink signal US2 at the beginning of the second frame F. It should be noted that the stylus pen 22 may also select to release the pairing with the position detection device 3 when not receiving the uplink signal US2 continuously in more than two frames F.

[0078] The stylus pen 22 that has chosen to cancel the pairing with the position detection device 3 cancels the pairing with the position detection device 3 by returning from the second communication mode to the detection mode. The stylus pen 22 that has returned to the detection mode no longer sends the downlink signal DS2, so the sensor controller 31 cannot receive the downlink signal DS2 in each time slot TS1, TS2, and TS3. The sensor controller 31 also performs the same processing as the stylus pen 22 in each frame F, cancels the pairing with the stylus pen 22 based on the failure to receive the downlink signal DS2, and returns to the detection mode. The processing after both parties return to the detection mode is referred to Figure 6 As explained.

[0079] Here, in Figure 7 In the description of the release of pairing in the second protocol, the same is true in the first protocol. Figure 7 In the figure, an example of releasing the pairing based on the reception status of the uplink signal US and the downlink signal DS is described, but it is also possible to reach a consensus on releasing the pairing between the stylus 2 and the sensor controller 31 by using short-range wireless communication of the wireless communication units 24 and 33, and both parties return to the detection mode based on the result.

[0080] As described above, according to the position detection system 1 of the present embodiment, by means of the multi-protocol simultaneous activation uplink signal SMA-US transmitted by the position detection device 3 supporting both the first protocol and the second protocol, it is possible to activate the stylus 21 supporting only the first protocol, not to mention the stylus 22 supporting both the first protocol and the second protocol, thereby preventing the old stylus 21 supporting only the first protocol from becoming unable to be used in the new position detection device 3 supporting the second protocol. In addition, since both the stylus 21 and 22 can be activated by one uplink signal, namely the multi-protocol simultaneous activation uplink signal SMA-US, it is possible to prevent the search efficiency of the stylus 2 from decreasing compared to the case where the uplink signals US1 and US2 are transmitted alternately at the beginning of each frame F.

[0081] Here, the processing when the stylus pen 22 approaches the panel surface 3a of the position detection device 3 (hereinafter, the position detection device 3 is referred to as the "old type position detection device 3" and the sensor controller 31 provided in the old type position detection device 3 is referred to as the "old type sensor controller 31") that only supports the first protocol but not the second protocol is described.

[0082] Figure 82 is a diagram showing the operation modes of the old type sensor controller 31 and the stylus 21 and 22 and the timing of sending and receiving each signal. The figure shows a situation where the stylus 22 is close to the panel surface 3a of the old type position detection device 3. As shown in the figure, the old type sensor controller 31 is configured to repeatedly perform the transmission of the uplink signal US1, the reception operation R of the downlink signal DS, and the transmission and reception operation T of the finger detection signal. The old type sensor controller 31 does not send the multi-protocol simultaneous activation uplink signal SMA-US.

[0083] As reference Figure 6 As described above, the stylus pen 22 in the detection mode continuously performs the receiving action R of the uplink signal US, and determines whether the uplink signal US1 is included based on the signal received as a result. If it is determined that the uplink signal US1 is included, it further determines whether the uplink signal US1 is attached with subsequent data for activating the stylus pen 2 with the second protocol. Figure 8 In the case of , since there is no subsequent data, the stylus pen 22 determines that there is no subsequent data in this determination and enters the first communication mode. The stylus pen 22 that enters the first communication mode immediately sends the downlink signal DS1. The subsequent processing is the same as in Figure 5 The processing of the stylus pen 21 described in is the same. In this way, when the stylus pen 22 approaches the panel surface 3a of the old type position detection device 3, it starts communication with the old type sensor controller 31 in the first communication mode.

[0084] Fig. 9 1 is a diagram showing the operation modes of the sensor controller 31 and the stylus 21 and 22 and the timing of sending and receiving each signal according to the first modified example of the first embodiment of the present invention. Figure 6 Similarly, the case where the stylus pen 22 is close to the panel surface 3 a is shown.

[0085] This variant is different from the present embodiment in that the stylus pen 22 that receives the multi-protocol simultaneous activation uplink signal SMA-US when entering the detection mode does not start entering the second communication mode and sending the downlink signal DS2 in the frame after receiving the multi-protocol simultaneous activation uplink signal SMA-US, but in the next frame (typically, the next frame). In this way, it is also possible to receive only the multi-protocol simultaneous activation uplink signal SMA-US in the first frame, so that the communication starts from the next frame.

[0086] Fig.10 2 is a diagram showing the operation modes of the sensor controller 31 and the stylus 21 and 22 and the timing of sending and receiving each signal according to the second modified example of the first embodiment of the present invention. Figure 4Similarly, the case where neither the stylus pens 21 nor 22 exists near the panel surface 3 a is shown.

[0087] This modification example is different from the present embodiment in that two types of uplink signals US2 are used. The first type of uplink signal US2 is the same as the uplink signal US2 used in the present embodiment, and is sent as a part of the multi-protocol simultaneous activation uplink signal SMA-US when the sensor controller 31 enters the detection mode. The second type of uplink signal US2 is a signal that is set differently from the first type of uplink signal US2. As examples of such settings, the code length of the spread spectrum code, the coding scheme of the spread spectrum code, the frequency of the carrier signal, etc. can be cited.

[0088] In the following, if the first type of uplink signal US2 setting is referred to as setting A, the second type of uplink signal US2 setting is referred to as setting B, the uplink signal US2 transmitted with setting A is referred to as uplink signal US2(A), and the uplink signal US2 transmitted with setting B is referred to as uplink signal US2(B), then Fig.10 As shown, the sensor controller 31 is configured to execute the transmission of the multi-protocol simultaneous activation uplink signal SMA-US that also serves as the transmission of the uplink signal US2(A) and the transmission of the uplink signal US2(B) according to a prescribed plan. The prescribed plan may be, for example, to alternately transmit the multi-protocol simultaneous activation uplink signal SMA-US and the uplink signal US2(B) in units of frame F.

[0089] The stylus pen 22 supporting the second protocol is configured to alternately or simultaneously wait for the multi-protocol simultaneous activation uplink signal SMA-US and the uplink signal US2(B), and to use the settings (spread spectrum code, frequency, etc.) of the received signals to perform the subsequent transmission of the downlink signal DS2. The sensor controller 31 waits for the downlink signal DS2 transmitted with the setting A in the frame F in which the multi-protocol simultaneous activation uplink signal SMA-US is transmitted, and waits for the downlink signal DS2 transmitted with the setting B in the frame F in which the uplink signal US2(B) is transmitted. As a result, when the sensor controller 31 receives the downlink signal DS2 in the frame in which the multi-protocol simultaneous activation uplink signal SMA-US is transmitted, the subsequent communication is performed with the setting A, and when the sensor controller 31 receives the downlink signal DS2 in the frame in which the uplink signal US2(B) is transmitted, the subsequent communication is performed with the setting B. By doing so, even when communication under the setting of one party becomes difficult due to the generation of strong external noise, for example, the possibility of continuing communication with the setting of the other party is increased.

[0090] Next, the position detection system 1 of the second embodiment of the present invention is described. The position detection system 1 of this embodiment is different from the position detection system 1 of the first embodiment in that the uplink signal US2 is sent at the beginning of each frame F instead of the multi-protocol simultaneous activation uplink signal SMA-US, and the uplink signal US1 is sent within the reserved time set in each frame F. In other points, it is the same as the position detection system 1 of the first embodiment, so the following description focuses on the differences from the position detection system 1 of the first embodiment.

[0091] Fig.11 1 is a diagram showing the operation mode of the sensor controller 31 and the stylus 21 and 22 of the present embodiment and the timing of sending and receiving each signal. In this figure, a situation where neither the stylus 21 or 22 is present near the panel surface 3a is shown. As shown in this figure, when the sensor controller 31 of the present embodiment enters the detection mode, it sets the reservation time RT used for the first protocol in the frame F set by the second protocol. Fig.11 In the example, the reservation time RT is set at the end of each frame F, but it can also be set at other time in the frame F (except the time for sending the uplink signal US2).

[0092] The sensor controller 31 sequentially performs the transmission operation R of the uplink signal US1 and the reception operation R of the downlink signal DS1 within the reservation time RT. When the downlink signal DS1 is received through the reception operation, the sensor controller 31 and Figure 5 In the example shown, the first communication mode is entered, and communication with the stylus 21 or the stylus 22 under the first protocol is started.

[0093] The sensor controller 31 transmits the uplink signal US2 at the beginning of each frame F as usual, and receives the downlink signal DS2 in each time slot TS1 and TS2 set in the frame F. Figure 4 The reason why the number of time slots set in frame F is smaller than that in frame F is that a reservation time RT is set in frame F. That is, the sensor controller 31 is configured to perform a reception operation of the downlink signal DS2 in the remaining time after the reservation time RT is removed from frame F. After receiving the downlink signal DS2, the sensor controller 31 communicates with the Figure 6 In the example shown, the second communication mode is entered and communication under the second protocol is started with the stylus pen 22. After communication under the second protocol is started with the stylus pen 22, the sensor controller 31 may not set the reservation time RT in the frame.

[0094] As described above, in the position detection system 1 of the present embodiment, since the sensor controller 31 is configured to set the reservation time RT within the frame F represented by the uplink signal US2 and to send the uplink signal US1 within the reservation time RT, the position detection system 1 of the present embodiment, as in the first embodiment, can prevent the search efficiency of the stylus pen 2 from decreasing while preventing an old stylus pen 21 that only supports the first protocol from becoming unusable in a new position detection device 3 that supports the second protocol.

[0095] Here, according to the present embodiment, the stylus pen 22 sometimes starts communication with the sensor controller 31 with the first protocol according to the timing of approaching the panel surface 3a. However, in the case where both the stylus pen 2 and the sensor controller 31 support the second protocol, it is preferable to communicate with the second protocol instead of the first protocol. Therefore, in the present embodiment, the stylus pen 22 may be configured to store setting information indicating either the first protocol or the second protocol, and transmit a downlink signal DS based on the protocol of one party when receiving an uplink signal US for activating the stylus pen with the protocol of the one party indicated by the setting information, and not transmit a downlink signal DS based on the protocol of the other party when receiving an uplink signal US for activating the stylus pen 2 with the protocol of the other party that is not the protocol of the one party indicated by the setting information. In this way, the protocol for transmitting the downlink signal DS can be limited to one, so that bidirectional communication can be started with the new second protocol instead of the old first protocol.

[0096] As mentioned above, although the preferred embodiment of the present invention has been described, the present invention is not limited to such embodiment at all, and the present invention can be implemented in various forms within the scope not departing from the gist of the present invention.

[0097] For example, in the above-mentioned first embodiment, an example is described in which a multi-protocol simultaneously activated uplink signal SMA-US is constructed by adding rear-end data capable of activating the stylus pen 2 with a second protocol to a front half portion configured to activate the stylus pen 2 with a first protocol. However, in addition to such a multi-protocol simultaneously activated uplink signal SMA-US, a multi-protocol simultaneously activated uplink signal SMA-US may be used in which a front half portion configured to activate the stylus pen 2 with a third protocol (a protocol different from both the first and second protocols) is added with rear-end data capable of activating the stylus pen 2 with a fourth protocol (a protocol different from both the first to third protocols). In this case, when determining whether the uplink signal US1 is included in the received signal, the stylus 2 that supports all the first to fourth protocols also determines whether the uplink signal US3 that is configured to activate the stylus 2 with the third protocol is included in the received signal. When it is determined that the uplink signal US3 is included in the received signal, it is further determined whether subsequent data (second subsequent data) for activating the stylus 2 with the fourth protocol is attached to the uplink signal US3. When it is determined that the subsequent data (second subsequent data) for activating the stylus 2 with the fourth protocol is attached, the downlink signal DS may be sent using the fourth protocol.

[0098] In addition, in the first embodiment, an example of using the multi-protocol simultaneous activation uplink signal SMA-US to transmit a signal for activating the stylus pen using two different protocols is described, but a signal for activating the stylus pen using three or more different protocols may be transmitted. In this case, the sensor controller 31 may append a plurality of subsequent data corresponding to each protocol to the first front half in the order from the old protocol to the new protocol.

[0099] In addition, the sensor controller 31 may also use the multi-protocol simultaneous activation uplink signal SMA-US to send a signal for activating devices other than the stylus, such as an eraser device, a left-hand device, a smart phone, a smart watch, etc. In this case, these devices are preferably configured to be able to determine whether subsequent data is attached in the same manner as the stylus 22 described in the first embodiment.

[0100] Description of Reference Numerals

[0101] 1 Position detection system

[0102] 2, 21, 22 Stylus

[0103] 3 Position detection device

[0104] 3a Panel surface

[0105] 20 Core

[0106] 21 Pen tip electrode

[0107] 21a Pen tip

[0108] 21b Pen ring

[0109] 22. Pressure sensor

[0110] 23 Processing Department

[0111] 24, 33 Wireless Communication Department

[0112] 25 Batteries

[0113] 30 Sensors

[0114] 31 Sensor Controller

[0115] 32 Host processor

[0116] DS, DS1, DS2 downlink signals

[0117] F Frame

[0118] R Receive Action

[0119] RT Appointment Time

[0120] SMA-US Multi-protocol Simultaneous Activation of Uplink Signals

[0121] T Send and receive action

[0122] TS1, TS2, TS3 time slots

[0123] US, US1, US2 Uplink signals.

Claims

1. A position detection device operates in a detection mode of sending a multi-protocol simultaneous activation uplink signal, wherein the multi-protocol simultaneous activation uplink signal is formed by appending subsequent data for activating the stylus with a second protocol different from the first protocol to a front half configured to activate the stylus with a first protocol.

2. The position detection device according to claim 1, The detection mode is a mode of waiting for both a first downlink signal transmitted by the first protocol and a second downlink signal transmitted by the second protocol within a frame indicated by the multi-protocol simultaneous activation uplink signal after the multi-protocol simultaneous activation uplink signal is transmitted.

3. The position detection device according to claim 2, After transmitting the multi-protocol simultaneously active uplink signal, the position detection device operating in the detection mode determines whether the signal received in the frame indicated by the multi-protocol simultaneously active uplink signal is the first downlink signal or the second downlink signal.

4. The position detection device according to claim 2 or 3, When the position detection device receives the first downlink signal in the detection mode, it enters a first communication mode of periodically sending a first uplink signal according to the first protocol, When the position detection device receives the second downlink signal in the detection mode, it enters the second communication mode of periodically transmitting the second uplink signal according to the second protocol.

5. The position detection device according to claim 4, The position detection device returns to the detection mode when the first downlink signal is not received in the first communication mode and when the second downlink signal is not received in the second communication mode.

6. The position detection device according to any one of claims 1 to 3, The detection mode is a mode in which the transmission of the multi-protocol simultaneous active uplink signal and the transmission of the second uplink signal according to the second protocol are performed according to a predetermined plan.

7. A touch pen, comprising: a first determination unit configured to determine whether a first uplink signal configured to enable the stylus to be activated using a first protocol is included in the received signal; a second determination unit, which, when the first determination unit determines that the first uplink signal is included in the received signal, determines whether first subsequent data for activating the stylus pen using a second protocol different from the first protocol is added to the first uplink signal; and The transmitting unit transmits a downlink signal using the second protocol when the second determining unit determines that the first subsequent data is attached to the first uplink signal.

8. The stylus pen according to claim 7, The transmission unit transmits a downlink signal using the first protocol when the result of the determination by the second determination unit is negative.

9. The stylus pen according to claim 7 or 8, The first determination unit further determines whether a third uplink signal configured to activate the stylus pen using a third protocol different from both the first protocol and the second protocol is included in the received signal. The second determination unit determines whether second subsequent data for activating the stylus pen using a fourth protocol different from the first protocol, the second protocol, and the third protocol is added to the third uplink signal when the first determination unit determines that the third uplink signal is included in the received signal. The transmitting unit transmits a downlink signal using the fourth protocol when the second determining unit determines that the second subsequent data is attached to the third uplink signal.

10. The stylus pen according to claim 7, The transmitting unit starts transmission of the downlink signal based on the second protocol in a frame next to or later than a frame indicated by the received signal including the first subsequent data when the second determining unit determines that the first subsequent data is attached to the first uplink signal.

11. The stylus pen according to claim 7, The stylus pen is configured to be operable in a detection mode for performing determination on a received signal by the first determination unit and the second determination unit, and in a second communication mode for determining whether the received signal includes a second uplink signal based on the second protocol. When the stylus enters the detection mode, the stylus enters the second communication mode according to the second determination unit determining that the first subsequent data is attached to the first uplink signal.

12. The stylus pen according to claim 11, The stylus pen further includes a pairing state selection unit for selecting whether to continue pairing with the position detection device when entering the second communication mode. The stylus pen returns to the detection mode when the pairing state selection unit selects to release the pairing with the position detection device.

13. A position detection device that transmits a first uplink signal configured to activate a stylus pen using a first protocol different from a second protocol configured to activate the stylus pen in a frame format within a reserved time set in a frame represented by a second uplink signal configured to activate the stylus pen using a second protocol configured to frame the stylus pen.

14. The position detection device according to claim 13, The position detection device performs a reception operation of a first downlink signal transmitted using the first protocol within the reserved time.

15. The position detection device according to claim 13 or 14, The position detection device performs a reception operation of the second downlink signal transmitted using the second protocol during a remaining time after excluding the reserved time from the frame.

16. A stylus pen, storing setting information indicating either a first protocol or a second protocol that is different from each other, When an uplink signal is received for activating the stylus pen using the protocol of one party of the first protocol and the second protocol represented by the setting information, a downlink signal based on the protocol of the one party is sent. On the other hand, when an uplink signal is received for activating the stylus pen using the protocol of the other party that is not the protocol of the one party represented by the setting information, a downlink signal based on the protocol of the other party is not sent.

17. The stylus pen according to claim 16, The second protocol is a method of sending a downlink signal using a plurality of time slots set in a frame. The sensor controller is configured to transmit a first uplink signal for activating the stylus pen using the first protocol within a reserved time set in a frame indicated by the transmission of a second uplink signal for activating the stylus pen using the second protocol, When the setting information indicates the second protocol and the second uplink signal is received, the stylus pen transmits a downlink signal based on the second protocol within a remaining time after excluding the reserved time from the frame indicated by the second uplink signal.

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