Patent Application
20250165091
The present disclosure relates to a position detection device, a sensor controller, and a stylus. More particularly, the present disclosure relates to a stylus and a position detection device that prevents an old stylus supporting only an old protocol from being unusable by a new position detection device supporting a new protocol and a sensor controller included in the position detection device that bidirectionally communicates with the stylus.
A position detection device realizes pen input by detecting a position of a stylus in a touch surface. The position of the stylus is detected by bidirectional communication, via sensors arranged in the touch surface, between the stylus and a sensor controller included in the position detection device. Hereinafter, a signal transmitted from the sensor controller to the stylus will be referred to as an “uplink signal,” and a signal transmitted from the stylus to the sensor controller will be referred to as a “downlink signal.”
Japanese Patent No. 6603435 (hereinafter, referred to as Patent Document 1) discloses a technique capable of changing the time length of an uplink signal in a bidirectional communication system between a stylus and a sensor controller. In this technique, a length field (FIG. 3 of Patent Document 1) indicating the size of a command included in the uplink signal or a flag (FIG. 9 of Patent Document 1) indicating whether or not there is subsequent data in the uplink signal is arranged in order to recognize the uplink signal has variable time length.
Incidentally, a protocol that regulates the specific procedure of the bidirectional communication can change due to the emergence of a new technique. When the protocol changes, it is necessary to prevent an old stylus supporting only an old protocol from being unusable by a new position detection device supporting a new protocol.
The present disclosure has been made in view of the above circumstances to provide a position detection device and a stylus that can prevent an old stylus supporting only an old protocol from being unusable by a new position detection device supporting a new protocol, and a sensor controller included in the position detection device to bidirectionally communicate with the stylus.
It is conceivable, as a specific technique for configuring a new position detection device so as to be usable with an old stylus, to alternately transmit an uplink signal according to a new protocol and an uplink signal according to an old protocol such that communication can be started using both the new protocol and the old protocol. However, in this case the transmission frequency of the uplink signal by each protocol becomes ½, and thus, the search efficiency of the stylus deteriorates.
Thus, another object of the present disclosure is to prevent a decrease in the search efficiency of the stylus while providing a position detection device and a stylus that can prevent an old stylus supporting only an old protocol from being unusable by a new position detection device supporting a new protocol.
In addition, where a new position detection device supporting a new protocol uses a stylus supporting a new protocol, bidirectional communication preferably can be started using the new protocol instead of the old protocol.
Thus, another object of the present disclosure is to provide a stylus that can start bidirectional communication by using a new protocol instead of an old protocol where a new position detection device supporting a new protocol uses a stylus supporting a new protocol.
According to a first aspect of the present disclosure, there is provided a position detection device that operates in a detection mode. Here, a multiprotocol simultaneous activation uplink signal is transmitted, which is obtained by adding, to a first portion configured to activate the stylus using a first protocol, subsequent data for activating the stylus using a second protocol different from the first protocol.
According to the first aspect of the present disclosure, there is also provided a stylus that includes a first determination section that determines whether or not a first uplink signal configured to activate the stylus by using a first protocol is included in a received signal. If the first determination section determines that the first uplink signal is included in the received signal, a second determination section determines whether or not first subsequent data for activating the stylus by using a second protocol different from the first protocol is added to the first uplink signal. There is also a transmission section that transmits a downlink signal by using the second protocol if the second determination section determines that the first subsequent data is added to the first uplink signal.
According to a second aspect of the present disclosure, there is provided a position detection device which, in a reservation time set in a frame indicated by a second uplink signal configured to activate a stylus by using a second protocol of a frame system, a first uplink signal is transmitted to activate the stylus by using a first protocol different from the second protocol.
According to a third aspect of the present disclosure, there is provided a stylus in which setting information indicates either a first protocol or a second protocol, where the first protocol and second protocol are different. When an uplink signal for activating the stylus through either the first protocol or the second protocol is received, a downlink signal is transmitted using the one indicated protocol read from the setting information. Further, when an uplink signal for activating the stylus through the other protocol that is not the one indicated protocol by the setting information is received, the downlink signal is not transmitted using the other protocol.
According to the first aspect of the present disclosure, not only the stylus supporting both the first protocol and the second protocol but also the stylus supporting only the first protocol can be activated by the multiprotocol simultaneous activation uplink signal transmitted by the position detection device supporting both the first protocol and the second protocol. Therefore, it is possible to prevent an old stylus supporting only the first protocol from being unusable by a new position detection device supporting the second protocol. In addition, since both the stylus supporting only the first protocol and the stylus supporting both the first protocol and the second protocol can be activated by one uplink signal, the multiprotocol simultaneous activation uplink signal, a decrease in the search efficiency of the stylus can also be prevented.
According to the second aspect of the present disclosure, since the first uplink signal is transmitted in the reservation time set in the frame indicated by the second uplink signal, it is possible to prevent the old stylus supporting only the first protocol from being unusable by the new position detection device supporting the second protocol while also preventing a decrease in the search efficiency of the stylus.
According to the third aspect of the present disclosure, since the protocol used for transmitting the downlink signal can be limited to one type, where the stylus supporting a new protocol is used by the new position detection device supporting the new protocol, bidirectional communication can be started using the new protocol instead of the old protocol.
Each of the styluses 21 and 22 is a pen-type device capable of performing bidirectional communication 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 capacitance system, but the present disclosure is not limited to an active capacitance system and is also applicable to bidirectional communication performed by another system, such as an electromagnetic induction system.
The specific protocols used by the styluses 21 and 22 for the bidirectional communication are different. While the stylus 21 supports only a relatively old first protocol, the stylus 22 supports a relatively new second protocol and the first protocol. Hereinafter, in the case where it is not necessary to distinguish the styluses 21 and 22 from each other, the styluses 21 and 22 will collectively be referred to as a “stylus 2.”
The position detection device 3 is a computer that responds to input (pen input) by the stylus 2, and is, for example, a personal computer such as a smartphone, a tablet terminal, or a notebook personal computer. The panel surface 3a may also serve as a display surface of a display, and in this case, the display is arranged while overlapping the sensor 30.
The sensor 30 is a device used by the sensor controller 31 to perform the above-described bidirectional communication with the stylus 2 and has a sensor electrode group arranged in the panel surface 3a. Specifically, the sensor electrode group includes a plurality of X electrodes that each extend in a y-direction in the panel surface 3a and are juxtaposed at equal intervals in an x-direction and a plurality of Y electrodes that each extend in the x-direction in the panel surface 3a and are juxtaposed 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 may also be used as common electrodes in the display, and the position detection device 3 in this case is called an “in-cell type.” Otherwise, the position detection device 3 is called an “on-cell type” or an “out-cell type” when the plurality of X electrodes and the plurality of Y electrodes are not used as common electrodes in the display. When a pen tip electrode 21 arranged at the pen tip of the stylus 2 approaches the sensor electrode group in the sensor 30, capacitive coupling occurs therebetween. In an active capacitance system, the bidirectional communication between the stylus 2 and the sensor controller 31 is executed via the capacitive coupling. Hereinafter, a signal transmitted from the sensor controller 31 to the stylus 2 via the capacitive coupling is referred to as an “uplink signal US,” and a signal transmitted from the stylus 2 to the sensor controller 31 via the capacitive coupling is referred to as a “downlink signal DS.”
The uplink signal US is a signal including a command from the sensor controller 31 to the stylus 2 and notifies the stylus 2 of the transmission timing of the downlink signal DS.
The downlink signal DS is a signal including a position signal that causes the sensor controller 31 to detect a position (hereinafter, referred to as a “pen position”) of the stylus 2 in the panel surface 3a and a data signal modulated by data (hereinafter, referred to as “pen data”) to be transmitted to the sensor controller 31. The pen data may include a pen pressure value, switch information indicating the on/off state of a switch provided on the surface of the stylus 2, identification information of the stylus 2, and other data, in addition to a response to the command in the uplink signal US.
Uplink signals US1 and US2 (first and second uplink signals, respectively) depicted in
Here, in terms of the relation between the first protocol and the second protocol, typically, each protocol has different versions of the same communication standard (for example, an active capacitance system). For example, specific differences between the first protocol and the second protocol may appear in a reception timing of the downlink signal DS, a frequency of a carrier signal of the downlink signal DS, a modulation system of the data signal included in the downlink signal DS, a scheme of a spread code used to transmit the data signal included in the downlink signal DS, a format of the data signal included in the downlink signal DS, or a time slot used by the stylus 2 to transmit the downlink signal DS. It is possible differences also appear in the uplink signal US and the downlink signal DS. It should be noted that the first protocol and the second protocol may have different communication systems such as an active modulation system and an electromagnetic induction system.
In addition, in the present embodiment, the description continues on the assumption that the first protocol is a frameless-system protocol and that the second protocol is a frame-system protocol. However, this is only an example. The first protocol may be a frame-system protocol, and the second protocol may be a frameless-system protocol.
The frameless system is a system in which transmission of the downlink signal DS by the stylus 2 is performed immediately after the uplink signal US is received. The sensor controller 31 periodically transmits the uplink signal US, and the stylus 2 continuously performs a reception operation of the uplink signal US and immediately transmits the downlink signal DS when the uplink signal US is received.
On the other hand, the frame system is a system in which the sensor controller 31 sets a frame including a plurality of time slots. The sensor controller 31 transmits the uplink signal US at the beginning of the frame. In addition, the stylus 2 continuously performs a reception operation of the uplink signal US in the initial state and acquires the frame and a temporal position of each time slot set therein, according to a reception timing of the received uplink signal US. Then, the downlink signal DS is transmitted using each time slot. A time slot used by the stylus 2 to transmit the downlink signal DS may be designated by the sensor controller 31, and the stylus 2 in this case transmits the downlink signal DS by using the designated time slot. After receiving the uplink signal US once, the stylus 2 performs a reception operation of the uplink signal US only at the beginning of the frame.
The sensor controller 31 is an integrated circuit that carries out various types of functions by executing a program implemented as hardware or a program stored in a built-in memory. The functions of the sensor controller 31 include deriving the pen position and acquiring the pen data by executing the bidirectional communication with the stylus 2 and sequentially supplying reports including the derived pen position and the acquired pen data to the host processor 32.
In the present embodiment, the description continues on the assumption that the sensor controller 31 supports both the first protocol and the second protocol described above. The sensor controller 31 in this case is configured to be operable in a detection mode for detecting the stylus 2, a first communication mode for performing the bidirectional communication with the stylus 2 via the sensor 30 by using the first protocol, and a second communication mode for performing the bidirectional communication with the stylus 2 via the sensor 30 by using the second protocol. Hereinafter, in the case where it is not necessary to particularly distinguish the first communication mode and the second communication mode from each other, these will collectively be referred to as a “communication mode.”
In detection mode, the sensor controller 31 is configured to transmit the multiprotocol simultaneous activation uplink signal SMA-US at the beginning of the frame set according to the second protocol. Further, on the basis of the reception status of the downlink signal DS, the sensor controller 31 is configured to enter either the first communication mode or the second communication mode and execute the bidirectional communication with the stylus 2 according to the entered communication mode. Hereinafter, the entry of the sensor controller 31 into either of the communication modes will be referred to as “pairing with the stylus 2.”
The sensor controller 31 is also configured to derive the position of a finger on the panel surface 3a. This derivation is executed by, for example, a capacitance system. In this case, the sensor controller 31 supplies a finger detection signal, including pulses corresponding to the number of X electrodes, to each of the plurality of X electrodes in the sensor 30 and receives the signal at each of the plurality of Y electrodes in the sensor 30. Then, the correlation between the signal received at each Y electrode and the finger detection signal supplied to each X electrode is calculated, and the position of the finger is derived from a result of the calculation. The sensor controller 31 is configured to transmit and receive the finger detection signal at intervals of communication with the stylus 2 and sequentially supply reports including the position of the finger derived as a result thereof to the host processor 32.
The host processor 32 is a central processing unit of the position detection device 3 and is configured to execute an operating system of the position detection device 3 and various types of applications including a drawing application by executing a program stored in a built-in memory. A process performed by the operating system or drawing application uses a series of reports supplied from the sensor controller 31 to the host processor 32. These processes include generation and display of digital ink, movement of the cursor, detection of various gestures such as tapping and dragging, and other processes.
The wireless communication unit 33 is a device for communicating with another device including the stylus 2 by short-range wireless communication such as Bluetooth (registered trademark). The host processor 32 and the sensor controller 31 are configured to communicate with the stylus 2 by short-range wireless communication via the wireless communication unit 33.
The core body 20 is a rod-shaped member constituting the pen tip of the stylus 2. The pen tip electrode 21 is an electrode provided at the pen tip of the stylus 2 that includes a pen chip 21a, rod-shaped electrode provided at the tip end of the core body 20, and a pen ring 21b, a ring-shaped electrode provided in such a manner as to surround the core body 20. The stylus 2 is configured to receive the uplink signal US by using one of or both the pen chip 21a and the pen ring 21b and to transmit the downlink signal DS from each of the pen chip 21a and the pen ring 21b. While the sensor controller 31 derives a position from the downlink signal DS transmitted from the pen chip 21a and the downlink signal DS transmitted from the pen ring 21b and acquires the pen position derived from the downlink signal DS transmitted from the pen chip 21a, the sensor controller 31 performs a process of calculating the tilt (tilt angle) of the stylus 2 on the basis of the two derived positions.
The pressure sensor 22 is a sensor that detects a pressure applied to the pen tip of the stylus 2 by detecting a force transmitted through the core body 20. The value of the pressure detected by the pressure sensor 22 is supplied to the processing unit 23 as a pen pressure value.
The processing unit 23 is a central processing unit of the stylus 2 and generates the downlink signal DS upon receival of the uplink signal US from the sensor controller 31 via the pen tip electrode 21 and transmits the generated 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 receives the position signal in the downlink signal DS at each of the plurality of X electrodes and the plurality of Y electrodes configuring the sensor 30, approximates the distribution of the reception intensity of the position signal in each of the x-direction and the y-direction by a normal distribution curve, and derives the respective peak positions to derive the pen position. In addition, the sensor controller 31 receives the data signal in the downlink signal DS at one X electrode or one Y electrode closest to the most recently derived pen position and demodulates the received data signal to acquire the pen data transmitted by the stylus 2.
The processing unit 23 is configured to be operable in a detection mode to detect the sensor controller 31 and a first communication mode for performing the bidirectional communication with the sensor controller 31 via the sensor 30 by using the first protocol. Further, the processing unit 23 of the stylus 22 is configured to be operable also in a second communication mode for performing the bidirectional communication with the sensor controller 31 via the sensor 30 by using the second protocol. The first communication mode and the second communication mode may also collectively be referred to as a “communication mode” when it is not necessary to distinguish them from each other.
The processing unit 23 having entered the detection mode performs continuously or intermittently a reception operation of the uplink signal US. When the uplink signal US is received by the reception operation, the processing unit 23 enters the communication mode and starts the bidirectional communication with the sensor controller 31. As described above, the uplink signal US has a role of shifting the operation mode of the stylus 2 from the detection mode to the communication mode. Hereinafter, the entry of the stylus 2 into either of the communication modes will be referred to as “pairing with the position detection device 3 (or the sensor controller 31),” and the shift of the stylus 2 from the detection mode to the communication mode will be referred to as “activation.” In addition, the shift of the stylus 2 from the detection mode to the first communication mode will be referred to as “activation using the first protocol,” and the shift from the detection mode to the second communication mode will be referred to as “activation using the second protocol.” The uplink signal US1 transmitted using the first protocol activates the stylus 2 by using the first protocol. Similarly, the uplink signal US2 transmitted using the second protocol has a role of activating the stylus 2 by using the second protocol.
The wireless communication unit 24 is a device for communicating with another device including the position detection device 3 by short-range wireless communication such as Bluetooth (registered trademark). The processing unit 23 is configured to be capable of communicating with the host processor 32 and the sensor controller 31 in the position detection device 3 via the wireless communication unit 33 by short-range wireless communication.
The battery 25 is a power supply device for supplying operation electric power to each unit of the stylus 2 by which the processing unit 23 and the wireless communication unit 24 are configured to operate by.
The symbol “CRC” following the symbol “D3” is a cyclic code generated on the basis of the symbols “D1,” “D2,” and “D3,” and causes the stylus 2 to detect a reception error of the symbols “D1,” “D2,” and “D3.” Three symbols “D4,” “D5,” and “D6” following the symbol “CRC” represent commands for the stylus 2 as with the symbols “D1,” “D2,” and “D3.” The symbol “CRC” following the symbol “D6” is a cyclic code generated on the basis of the symbols “D4,” “D5,” and “D6,” and causes the stylus 2 to detect a reception error of the symbols “D4,” “D5,” and “D6.”
A portion from the top symbol “PRE” to the first symbol “CRC” is a first portion configured to activate the stylus 2 by using the first protocol and has a configuration similar to that of the uplink signal US1. A portion from the symbol “D4” to the second symbol “CRC” configures subsequent data for activating the stylus 2 through the second protocol. The configuration of the subsequent data is obtained by excluding the preamble data from the uplink signal US2.
The processing unit 23 of the stylus 21 that does not support the second protocol is configured to determine whether or not the received signal supplied from the pen tip electrode 21 includes the uplink signal US1, and to enter the first communication mode if it is determined to include the uplink signal US1. Therefore, if the multiprotocol simultaneous activation uplink signal SMA-US is received, the processing unit 23 of the stylus 21 determines that the uplink signal US1 has been received, only from the first portion thereof, and enters the first communication mode. The processing unit 23 having entered the first communication mode performs a process of generating the downlink signal DS1 based on receival of the uplink signal US1 and transmitting the generated downlink signal DS1. Subsequently, the processing unit 23 performs a reception operation (specifically, an operation of determining whether or not the uplink signal US1 is included in the received signal supplied from the pen tip electrode 21) of the uplink signal US again, and generates the downlink signal DS1 on the basis of the uplink signal US1 received as a result thereof and transmits the generated downlink signal DS1. Thereafter, the processing unit 23 repeatedly executes the similar process until the uplink signal US1 is no longer received. If the state where the uplink signal US1 is not received is continued for a predetermined period of time, the processing unit 23 of the stylus 21 returns to the detection mode.
On the other hand, the processing unit 23 of the stylus 22 that supports both the first protocol and the second protocol determines whether or not the first portion (the uplink signal US1) of the multiprotocol simultaneous activation uplink signal SMA-US is included in the received signal supplied from the pen tip electrode 21. If it is determined to be included, the second protocol further determines whether or not the above-described subsequent data is added to the detected first portion. If it is determined that the subsequent data is added, the processing unit 23 is configured to enter the second communication mode.
Here, since the second protocol is a frame-system protocol, the processing unit 23 of the stylus 22 acquires the frame and the temporal position of each time slot set therein, based upon the reception timing of the multiprotocol simultaneous activation uplink signal SMA-US, and transmits the downlink signal DS2 by using each time slot. Subsequently, the processing unit 23 performs a reception operation of the uplink signal US2 at the beginning of the next frame and performs a process similar to the above where the uplink signal US2 has been received. Thereafter, the processing unit 23 repeatedly executes the similar process until the uplink signal US2 is no longer received. If a state in which the uplink signal US2 is not received is continued for a predetermined period of time, the processing unit 23 of the stylus 22 returns to the detection mode.
In the determination as to whether or not the subsequent data is added to the detected first portion, where it is determined that no subsequent data is added (that is, in the case where the received uplink signal US is not the multiprotocol simultaneous activation uplink signal SMA-US but only the uplink signal US1), the processing unit 23 of the stylus 22 enters the first communication mode. In this case, the process executed by the processing unit 23 is similar to the process described for the processing unit 23 of the stylus 21. As described above, the processing unit 23 of the stylus 22 enters the first communication mode in the case where the sensor controller 31 does not support the second protocol.
Upon the reception operation R receiving the signal, the sensor controller 31 having entered the detection mode determines whether the signal is the downlink signal DS1 or DS2. This determination may be made, for example, by checking the difference (the frequency of the carrier signal of the downlink signal DS or the like) between the first protocol and the second protocol described above. In the example of
When receiving the downlink signal DS2 in the reception operation R performed in the time slots TS2 and TS3, the sensor controller 31 shifts to the second communication mode from the next frame F, and thereafter performs an operation according to the second protocol. Specifically, the uplink signal US2 is transmitted at the beginning of each frame F, and the reception operation R is executed in each of the time slots TS1, TS2, and TS3 while the transmission/reception operation T of the finger detection signal is interposed by using the time between the time slots TS1, TS2, and TS3. Accordingly, the bidirectional communication using the second protocol is realized between the sensor controller 31 and the stylus 22.
The stylus 22 selects whether to continue the pairing with the position detection device 3 in each frame F during the communication in the second communication mode (pairing state selection section). Specifically, in the case where the uplink signal US2 is received at the beginning of each frame F, continuation of the pairing with the position detection device 3 is selected, while, in the case where the uplink signal US2 is not received, cancellation of the pairing with the position detection device 3 is selected. In the example of
The stylus 22 having selected the cancellation of the pairing with the position detection device 3 cancels the pairing with the position detection device 3 by returning to the detection mode from the second communication mode. Since the stylus 22 that has returned to the detection mode no longer transmits the downlink signal DS2, the sensor controller 31 cannot receive the downlink signal DS2 in each of the time slots TS1, TS2, and TS3. The sensor controller 31 also performs the process similar to that of the stylus 22 in each frame F, cancels the pairing with the stylus 22 in response to the fact that the downlink signal DS2 is not received, and returns to the detection mode. The process performed after both return to the detection mode is as described above with reference to
Here, although the cancellation of the pairing in the second protocol has been described in
As described above, according to the position detection system 1 of the present embodiment, not only the stylus 22 supporting both the first protocol and the second protocol but also the stylus 21 supporting only the first protocol can be activated by the multiprotocol simultaneous activation uplink signal SMA-US transmitted by the position detection device 3 supporting both the first protocol and the second protocol, and thus, it is possible to prevent the old stylus 21 supporting only the first protocol from being unusable by the new position detection device 3 supporting the second protocol. In addition, since both of the styluses 21 and 22 can be activated by one uplink signal, the multiprotocol simultaneous activation uplink signal SMA-US, a decrease in the search efficiency of the stylus 2 is prevented as compared with a case where the uplink signals US1 and US2 are alternately transmitted at the beginning of each frame F.
Here, a process in the case where the stylus 22 approaches the panel surface 3a of the position detection device 3 (hereinafter, this position detection device 3 will be referred to as an “old-type position detection device 3,” and the sensor controller 31 provided in the old-type position detection device 3 will be referred to as an “old-type sensor controller 31”) that supports only the first protocol and does not support the second protocol will be described.
As described with reference to
The present modified example is different from the first embodiment in that the stylus 22, having received the multiprotocol simultaneous activation uplink signal SMA-US when entering the detection mode, starts the entry into the second communication mode and the transmission of the downlink signal DS2 not in a frame F where the multiprotocol simultaneous activation uplink signal SMA-US is received but in a subsequent frame F (typically, the next frame F). As described above, only the reception of the multiprotocol simultaneous activation uplink signal SMA-US may be performed in the first frame F, and the communication may be started from the next frame F.
The present modified example is different from the first embodiment in that two types of uplink signals US2 are used. The first type of uplink signal US2 is the same as that used in the present embodiment and is transmitted as a part of the multiprotocol simultaneous activation uplink signal SMA-US if the sensor controller 31 has entered the detection mode. The second type of uplink signal US2 is a signal whose settings are different from those of the first type of uplink signal US2. Examples of such settings include the code length of the spread code, the code structure of the spread code, and the frequency of the carrier signal.
Hereinafter, the setting of the first type of uplink signal US2 will be referred to as a setting A while the setting of the second type of uplink signal US2 will be referred to as a setting B. Assuming that the uplink signal US2 transmitted with the setting A is an uplink signal US2 (A) while the uplink signal US2 transmitted with the setting B is an uplink signal US2 (B), the sensor controller 31 is configured to transmit the multiprotocol simultaneous activation uplink signal SMA-US including the transmission of the uplink signal US2 (A) and transmit the uplink signal US2 (B) according to a predetermined schedule as depicted in
The stylus 22 supporting the second protocol is configured to alternately or simultaneously wait for the multiprotocol simultaneous activation uplink signal SMA-US and the uplink signal US2 (B) and perform the transmission of the subsequent downlink signal DS2 by using the settings (the spread code, frequency, and the like) of the received signal. The sensor controller 31 waits for the downlink signal DS2 transmitted with the setting A in the frame F transmitting the multiprotocol simultaneous activation uplink signal SMA-US and for the downlink signal DS2 transmitted with the setting B in the frame F transmitting the uplink signal US2 (B). As a result, if the downlink signal DS2 is received in the frame transmitting the multiprotocol simultaneous activation uplink signal SMA-US, the sensor controller 31 performs the subsequent communication with the setting A. If the downlink signal DS2 is received in the frame transmitting the uplink signal US2 (B), the sensor controller 31 performs the subsequent communication with the setting B. In this way, even if communication with one setting becomes difficult due to, for example, occurrence of strong external noise, the possibility of continuing the communication with the other setting increases.
Next, the position detection system 1 according to the present embodiment is different from the position detection system 1 according to the first embodiment in that the position detection system 1 according to the present embodiment executes the transmission of the uplink signal US2 at the beginning of each frame F instead of the transmission of the multiprotocol simultaneous activation uplink signal SMA-US or the execution of the transmission of the uplink signal US1 at reservation time set in each frame F. Since the other features are similar to those of the position detection system 1 according to the first embodiment, the following description will be made focusing on differences between the position detection system 1 according to the first embodiment and position detection system 1 according to the present embodiment.
The sensor controller 31 sequentially executes the transmission of the uplink signal US1 and the reception operation R of the downlink signal DS1 in the reservation time RT. If the downlink signal DS1 is received by the reception operation, the sensor controller 31 enters the first communication mode and starts communication with the stylus 21 or the stylus 22 by using the first protocol as in the example depicted in
The sensor controller 31 performs the transmission of the uplink signal US2 as usual at the beginning of each frame F, and performs the reception operation of the downlink signal DS2 in each of the time slots TS1 and TS2 set in the frame F. The number of time slots set in the frame Fis smaller than that in
As described above, in the position detection system 1 according to the present embodiment, since the reservation time RT is set in the frame F indicated by the uplink signal US2 and the sensor controller 31 is configured to transmit the uplink signal US1 therein, the position detection system 1 according to the present embodiment can also prevent the old stylus 21 supporting only the first protocol from being unusable by the new position detection device 3 supporting the second protocol, while preventing a decrease in the search efficiency of the stylus 2, as in the first embodiment.
Here, according to the present embodiment, the communication with the sensor controller 31 is started by using the first protocol depending on when the stylus 22 approaches the panel surface 3a. However, in the case where both the stylus 2 and the sensor controller 31 support the second protocol, it is preferable to perform communication by using the second protocol instead of the first protocol. Therefore, in the present embodiment, setting information indicating either the first protocol or the second protocol may be stored, and the stylus 22 may be configured such that, if the uplink signal US for activating the stylus 2 by using one protocol indicated by the setting information is received, the downlink signal DS is transmitted using the one protocol. If the uplink signal US for activating the stylus 2 by using the other protocol instead of the one protocol indicated by the setting information is received, the downlink signal DS is not transmitted using the other protocol. In this way, since the protocol used for transmitting the downlink signal DS can be limited to one type, the bidirectional communication can be started using the new second protocol instead of the old first protocol.
While the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to such foregoing embodiments. Persons of skill in the art will appreciate that various modifications may be made without departing from the scope of the present disclosure.
For example, in the above-described first embodiment, an example of using the multiprotocol simultaneous activation uplink signal SMA-US is described, in which the SMA-US is constituted by adding the subsequent data configured to activate the stylus 2 by using the second protocol to the first portion configured to activate the stylus 2 by using the first protocol. However, in addition to such SMA-US, a further multiprotocol simultaneous activation uplink signal SMA-US may be used, which is constituted by adding to a first portion configured to activate the stylus 2 through a third protocol (a protocol different from either of the first and second protocols), subsequent data configured to activate the stylus 2 by using a fourth protocol (a protocol different from any of the first to third protocols). In this case, when determining whether or not the uplink signal US1 is included in the received signal, the stylus 2 supporting any of the first to fourth protocols also determines whether or not a third uplink signal (US3) configured to activate the stylus 2 by using the third protocol is included in the received signal. If it is determined that the uplink signal US3 is included in the received signal, the stylus 2 supporting any of the first to fourth protocols further determines whether or not subsequent data (second subsequent data) for activating the stylus 2 by using the fourth protocol is added to the uplink signal US3. If it is determined that the uplink signal US3 is added, the transmission of the downlink signal DS can be performed using the fourth protocol.
In addition, in the above-described first embodiment, an example of transmitting the signal for activating the stylus 2 by using two different protocols by the multiprotocol simultaneous activation uplink signal SMA-US has been described, but a signal for activating the stylus 2 by using three or more different protocols may be transmitted. In this case, the sensor controller 31 can add a plurality of pieces of subsequent data supporting each protocol to the first portion, in the order from the older protocol.
In addition, the sensor controller 31 may transmit a signal for activating a device other than the stylus 2, such as an eraser device, a left-hand device, a smartphone, or a smartwatch, by the multiprotocol simultaneous activation uplink signal SMA-US. In this case, these devices are preferably configured to be capable of determining whether the subsequent data is added, as with the stylus 22 described in the first embodiment.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2023-194906 | Nov 2023 | JP | national |
