Touch state detection circuit, electronic device including touch state detection circuit, and touch state detection method

Abstract

To perform detection appropriate to various conditions compared with a case when fixing a scan condition of scan processing for detecting a touch state.SOLUTION: There is provided a touch IC20, which is connected to a capacitance-type touch sensor 18 composed of a plurality of sensor electrodes 18x and 18y disposed in a planar manner, and which detects a touch state of a user by executing scan processing that reads out and processes detection signals sequentially outputted from each of the sensor electrodes 18x and 18y. The touch IC20 comprises: a setting unit 30 which sets a scan condition related to an execution frequency of the scan processing or an execution cycle of the scan processing; and a detection unit 32 which detects the touch state by executing the scan processing under the set scan condition. When a determination condition indicating a situation in which the scan condition is required to be changed is satisfied, the setting unit 30 changes and resets the scan condition, and the detection unit 32 detects the touch state under the reset scan condition.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a touch state detection circuit, an electronic device including the touch state detection circuit, and a touch state detection method. [Background technology]

[0002] Conventionally, there are known touch state detection circuits that detect a touch state when a user's finger or the like touches a detection surface. For example, the touch state detection circuit described in Patent Document 1 below is connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, and detects the touch state by executing a scanning process that reads and processes detection signals output sequentially from each sensor electrode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-177591 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, a fixed time is set as the execution cycle of the scan process for detecting a touch state so that the touch state detection function can be utilized in various use cases. As a specific example, assuming a case where a user touches the detection surface with 10 fingers simultaneously, a long execution cycle is set so that the effect of electrical noise caused by such touches is not affected. However, with this setting, even when the number of user fingers touching the detection surface is small, the fixed time is required to detect the touch state, resulting in unnecessary waiting time.

[0005] Therefore, the present invention aims to provide a touch state detection circuit, an electronic device equipped with a touch state detection circuit, and a touch state detection method that can perform detection suitable for various conditions compared to when the scan conditions of the scan process for detecting a touch state are fixed. [Means for solving the problem]

[0006] A touch state detection circuit according to a first aspect of the present invention is a touch state detection circuit that is connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a planar shape, and detects a user's touch state by executing a scan process that reads and processes detection signals output sequentially from each of the sensor electrodes. The touch state detection circuit includes a setting unit that sets scan conditions related to the execution frequency or execution cycle of the scan process, and a detection unit that executes the scan process under the set scan conditions to detect the touch state. When a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the setting unit changes and resets the scan conditions, and the detection unit detects the touch state under the reset scan conditions.

[0007] In a touch state detection circuit according to a second aspect of the present invention, when a first condition is satisfied as the judgment condition, the setting unit changes and resets the scan conditions so that the execution frequency is higher than a reference value or so that the execution period is shorter than a reference value.

[0008] In the touch state detection circuit according to the third aspect of the present invention, the first condition indicates that, when the touch state by one or more fingers of the user is detected, the number of the fingers is equal to or less than a threshold value.

[0009] In the touch state detection circuit according to a fourth aspect of the present invention, the threshold value is the number of fingers on one hand of the user.

[0010] In the touch state detection circuit according to a fifth aspect of the present invention, the first condition indicates that at least the touch state by the user's palm has been detected.

[0011] In the touch state detection circuit according to a sixth aspect of the present invention, the first condition at least indicates that when the touch state by the user's finger is detected, the moving speed of the finger is equal to or less than a threshold.

[0012] In the touch state detection circuit according to a seventh aspect of the present invention, the first condition at least indicates that the size of the touch sensor is equal to or smaller than a threshold value.

[0013] In the touch state detection circuit according to an eighth aspect of the present invention, the first condition indicates that at least when the touch sensor is disposed so as to overlap a display panel, a refresh rate of the display panel is higher than a threshold value.

[0014] In a touch state detection circuit according to a ninth aspect of the present invention, the first condition indicates that there is at least a partial area within the entire area in which the touch state can be detected by the touch sensor that is not intended to be touched by the user.

[0015] In a touch state detection circuit according to a tenth aspect of the present invention, when a second condition is satisfied as the judgment condition, the setting unit changes and resets the scan conditions so that the execution frequency is lower than a reference value or so that the execution period is longer than a reference value.

[0016] In a touch state detection circuit according to an eleventh aspect of the present invention, the second condition indicates that, when the touch state by one or more fingers of the user is detected, the number of the fingers is equal to or greater than a threshold value.

[0017] A touch state detection circuit according to a twelfth aspect of the present invention is a touch state detection circuit that further detects the pen state of the electronic pen by executing the scanning process, and the second condition indicates at least that an unused state of the electronic pen has been detected.

[0018] A touch state detection circuit according to a thirteenth aspect of the present invention is a touch state detection circuit that detects the pen state and the touch state of an electronic pen in a time-division manner by executing the scan process, wherein the scan condition indicates a ratio of the execution frequency of the scan process for detecting the touch state to the execution frequency of the scan process for detecting the pen state, and the setting unit changes and resets the execution frequency ratio when the judgment condition is satisfied.

[0019] An electronic device according to a fourteenth aspect of the present invention includes a capacitive touch sensor having a plurality of sensor electrodes arranged in a planar shape, and a touch state detection circuit according to any one of the first to thirteenth aspects connected to the touch sensor.

[0020] A fifteenth aspect of the present invention provides a touch state detection method that is connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, and detects a user's touch state by performing a scan process that reads and processes detection signals output sequentially from each of the sensor electrodes, the touch state detection method sequentially repeating a setting step of setting scan conditions related to the execution frequency or execution cycle of the scan process, and a detection step of performing the scan process under the set scan conditions to detect the touch state, in which, when a determination condition indicating a situation in which the scan conditions should be changed is satisfied in the setting step, the scan conditions are changed and reset, and in the detection step the touch state is detected under the reset scan conditions. [Effects of the Invention]

[0021] According to the present invention, detection suitable for various conditions can be performed compared to when the scan conditions of the scan process for detecting a touch state are fixed. [Brief explanation of the drawings]

[0022] [Figure 1]1 is a diagram illustrating the overall configuration of an input system incorporating a touch state detection circuit according to a first embodiment of the present invention. [Figure 2] FIG. 10 is a sequence diagram showing the flow of processing for pen detection and touch detection in the touch IC. [Figure 3] 2 is a functional block diagram showing a touch detection function of the touch IC of FIG. 1. [Figure 4] 10 is a graph for conceptually explaining a touch execution cycle. [Figure 5] 10 is a graph for conceptually explaining scan time. [Figure 6] FIG. 10 is a diagram for explaining the definition of a scan rate as a scan condition. [Figure 7] FIG. 10 is a diagram illustrating an example of a combination of a determination condition and a scan rate when the determination condition is satisfied. [Figure 8] 10 is a flowchart showing an example of the processing flow of the touch IC when touch detection is performed by the touch detection function. [Figure 9] 10 is a flowchart showing an example of the process flow for scan setting in step SP14 of FIG. 8. [Figure 10] FIG. 11 is a diagram showing an example of a combination of a determination condition and a touch execution period (scan time) when the determination condition is satisfied according to the second embodiment. [Figure 11] 10 is a flowchart showing an example of the process flow for scan setting in step SP14 of FIG. 8 according to the second embodiment. [Figure 12] FIG. 10 is a diagram for conceptually explaining the ratio of scan execution frequencies. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, a touch state detection circuit, an electronic device including the touch state detection circuit, and a touch state detection method according to various embodiments of the present invention will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same elements or elements having the same functions are denoted by the same reference numerals as much as possible in the respective drawings, and redundant description will be omitted.

[0024] [First embodiment] First, a touch state detection circuit, an electronic device including the touch state detection circuit, and a touch state detection method according to a first embodiment of the present invention will be described with reference to FIGS.

[0025] <Overall structure> Fig. 1 is a diagram showing the overall configuration of an input system 10 incorporating a touch state detection circuit according to a first embodiment of the present invention. As shown in Fig. 1, the input system 10 basically comprises an electronic device 12 having a touch panel display and an electronic pen 14, which is a pen-type pointing device. The electronic pen 14 is also called a "stylus."

[0026] The electronic device 12 is configured, for example, as a tablet terminal, a smartphone, or a personal computer. A user can write pictures or characters on the electronic device 12 by holding the electronic pen 14 in one hand and pressing the tip of the pen against the detection surface 16 of the electronic device 12 and moving the pen. In addition, the user can perform desired operations via the displayed user controls by touching the detection surface 16 with their own finger F.

[0027] The electronic device 12 includes a touch sensor 18, a touch IC (Integrated Circuit) 20 that is a touch state detection circuit, and a host processor 22. The touch sensor 18 is formed by combining multiple electrodes that are arranged on top of a display panel (not shown) such as a liquid crystal display. The touch sensor 18 is a capacitive touch sensor that has multiple sensor electrodes arranged in a planar form. The touch sensor 18 includes multiple sensor electrodes 18x for detecting a position on the X axis and multiple sensor electrodes 18y for detecting a position on the Y axis. The x and y directions shown in this figure correspond to the X and Y axes of a Cartesian coordinate system defined on the detection surface 16 formed by the touch sensor 18.

[0028] The strip-shaped sensor electrodes 18x extend in the y direction and are arranged at equal intervals along the x direction. The strip-shaped sensor electrodes 18y extend in the x direction and are arranged at equal intervals along the y direction. Note that the touch sensor 18 may be a self-capacitance sensor in which block-shaped electrodes are arranged in a two-dimensional lattice pattern, instead of the mutual capacitance sensor described above.

[0029] The touch IC 20 is an integrated circuit configured to be able to execute firmware 24 and is connected to each of the multiple sensor electrodes 18x, 18y that make up the touch sensor 18. The firmware 24 executes a scan process that reads and processes detection signals sequentially output from each of the sensor electrodes 18x, 18y. The firmware 24 is configured to implement a touch detection function 26 that executes the scan process to detect the touch state of a detection target, such as a user's finger F (hereinafter referred to as "touch detection"), and a pen detection function 28 that executes the scan process to detect the pen state of the electronic pen 14 (hereinafter referred to as "pen detection"). The touch state includes a touch state by one or more of the user's fingers F and a touch state by the user's palm (a part of the hand that is larger than the fingers F and includes the palm, back of the hand, fist, etc.). The touch state refers to the position of the finger F or palm that touches the detection surface 16, etc. The pen state refers to the position, tilt, writing pressure, etc. of the electronic pen 14 that touches the detection surface 16.

[0030] 2 is a sequence diagram showing the flow of pen detection and touch detection processing in touch IC 20. As shown in FIG. 2, touch IC 20 is configured to repeatedly execute pen detection by pen detection function 28 (step SP10) and touch detection by touch detection function 26 (step SP12) in a time-division manner. Here, the execution frequency of pen detection and the execution frequency of touch detection are preset to have a predetermined ratio. In the example of FIG. 2, the execution frequency ratio of pen detection to touch detection in one repetition cycle is illustrated as 1:1, but the execution frequency ratio may be any of 1:n, n:1, or n:m (where n and m are integers).

[0031] The pen detection in step SP10 includes, for example, a scan process (global scan or sector scan) of the touch sensor 18, a reception and analysis process of a downlink signal transmitted from the electronic pen 14, a process of estimating the pen state of the electronic pen 14, and a generation and transmission process of an uplink signal including a command to the electronic pen 14. Furthermore, the touch detection in step SP12 includes, for example, a scan process of the touch sensor 18, a process of creating a heat map (two-dimensional distribution of detection levels) on the touch sensor 18, and a process of estimating the touch state of the finger F.

[0032] 1, the host processor 22 is a processor including a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The host processor 22 reads and executes programs from a memory (not shown) to perform, for example, a process of generating digital ink using data from the touch IC 20, a rendering process for displaying the drawing content indicated by the digital ink, and the like.

[0033] <Functional configuration of touch IC20> Fig. 3 is a functional block diagram showing the touch detection function 26 included in the touch IC 20 of Fig. 1. As shown in Fig. 3, the touch detection function 26 includes a setting unit 30, a detection unit 32, an acquisition unit 34, and a determination unit 36.

[0034] The setting unit 30 sets scan conditions related to the frequency of execution of the scan process or the execution cycle of the scan process. Here, the execution frequency of the scan process indicates the time interval at which the scan process for detecting a touch state is repeated. Furthermore, the execution cycle of the scan process is the execution cycle of the scan process for detecting a touch state (hereinafter referred to as the "touch execution cycle").

[0035] FIG. 4 is a graph for conceptually explaining the touch execution cycle. The graph in FIG. 4 is a single-axis graph of time, with each scan process indicated by a square. As shown in FIG. 4, when touch detection is in the ON state, the scan process for detecting the touch state is repeatedly executed multiple times. Note that this scan process does not have to be repeatedly executed multiple times, and may be executed intermittently, for example, by alternating with the scan process for detecting the pen state. The touch execution cycle is specifically the scan time Ta required for one scan process. Note that, because one scan time Ta is short, the touch execution cycle may be an integrated scan time Tb obtained by integrating the scan time Ta for a predetermined number of scan processes.

[0036] The scan time Ta (the scan time required for one scan process) is the time it takes, starting from the timing of setting the scan conditions, to acquire the frame data, which is the detection data for one scan process, and then start setting the scan conditions again. A specified time is set as the scan time Ta.

[0037] FIG. 5 is a graph for conceptually explaining the scan time Ta. The graph in FIG. 5 corresponds to an enlarged view of the scan time Ta portion of the graph in FIG. 4. As shown in FIG. 5, the scan time Ta includes an actual scan time T1 and a non-scan time T2. The actual scan time T1 (t1 to t2) indicates the time required for actual scan processing, such as reading out the detection signal, performing calculations, and outputting the detection data. The non-scan time T2 (t2 to t3) indicates the waiting time until the scan conditions are set again after the detection data is output.

[0038] In the first embodiment, the scan condition will be described as a scan rate, which is related to the frequency of a scan process for detecting a touch state. The scan rate is also referred to as a scan frequency. FIG. 6 is a diagram for explaining the definition of the scan rate as a scan condition, and similarly to FIG. 4, one scan process is represented by a square. As shown in FIG. 6, the scan rate is represented, for example, as the number of scan processes performed per given time period. For example, if the scan process is repeated five times with a scan time Ta of 1 [sec], the scan rate for executing the five scan processes is 1 [Hz]. In contrast, if the scan process is repeated five times with a scan time Ta of 0.5 [sec], the scan rate for executing the five scan processes is 2 [Hz]. In other words, the scan rate changes according to the change in the scan time Ta. Furthermore, in a time period in which multiple scan rates coexist, the scan rate may be calculated as the average value of the scan rates in that time period. For example, if the scan process is repeated five times with a scan time Ta of 1 sec, and then the scan process is repeated five times with a scan time Ta of 0.5 sec, the average scan rate for the entire process, which involves performing a total of 10 scan processes, will be 1.3 Hz.

[0039] The setting unit 30 sets the initial value of the scan rate to, for example, 100 [Hz]. Furthermore, when a determination condition indicating a situation in which the scan rate, which is a scan condition, should be changed is satisfied, the setting unit 30 changes and resets the scan rate. The determination condition includes a first condition indicating a situation in which the scan rate should be increased relative to a reference value, and a second condition indicating a situation in which the scan rate should be decreased relative to the reference value. The reference value here is a reference value of the scan rate, which may be a value set in advance as, for example, an initial value, or may be the value set previously immediately before the determination of the determination condition is satisfied.

[0040] When the first condition is satisfied, the setting unit 30 increases the scan rate relative to the reference rate. For example, if the reference rate is the previously set value and the previously set value is 100 [Hz], the setting unit 30 resets the scan rate to 150 [Hz]. On the other hand, when it is determined that the second condition is satisfied, the setting unit 30 decreases the scan rate relative to the reference rate. For example, if the reference rate is the previously set value and the previously set value is 150 [Hz], the setting unit 30 resets the scan rate to 100 [Hz].

[0041] The setting unit 30 resets elements correlated with the scan time Ta that determines the reset scan rate, and resets the scan time Ta itself to a cycle corresponding to these elements. Elements correlated with the scan time Ta include, for example, the length of the code multiplexed signal for touch detection and the time required to calculate the coordinates of the detected finger F.

[0042] The code-multiplexed signal length is the length of a signal in a code-multiplexing system that supplies a signal with a different code pattern for each transmission conductor. When the detection range is large or there are many detection targets, it is necessary to increase the combination of signals with different code patterns for each transmission conductor, and it is therefore necessary to increase the code-multiplexed signal length. Therefore, in such cases, the setting unit 30 sets the code-multiplexed signal length to be longer, thereby lengthening the actual scan time T1 within the scan time Ta accordingly. On the other hand, when the detection range is small or there are few detection targets, the code-multiplexed signal length may be shorter. Therefore, in such cases, the setting unit 30 sets the code-multiplexed signal length to be shorter, thereby shortening the actual scan time T1 within the scan time Ta accordingly.

[0043] Furthermore, the time required to calculate the coordinates of the detected fingers F depends on the number of fingers F. When there are many fingers F, the time required to calculate the coordinates of the fingers F becomes longer, and the actual scan time T1 in the scan time Ta becomes longer accordingly. On the other hand, when there are few fingers F, the time required to calculate the coordinates of the fingers F becomes shorter, and the actual scan time T1 in the scan time Ta becomes shorter accordingly.

[0044] Furthermore, the scan time Ta can be changed by changing the specified time set as the scan time Ta. When the detection range is large or there are many detection targets, the actual scan time T1 in the scan time Ta becomes longer by lengthening the code multiplexed signal length or the time required to calculate the coordinates of the finger F as described above. Therefore, the setting unit 30 correspondingly sets the specified time, i.e., the scan time Ta, to be longer, thereby lowering the scan rate. On the other hand, when the detection range is small or there are few detection targets, the actual scan time T1 in the scan time Ta becomes shorter by shortening the code multiplexed signal length or the time required to calculate the coordinates of the finger F as described above. Therefore, the setting unit 30 correspondingly shortens the specified time, i.e., the scan time Ta, thereby increasing the scan rate.

[0045] In this way, the setting unit 30 optimizes the scan time Ta and the scan rate determined by the scan time Ta. This ensures that the actual scan time T1 in the scan time Ta is long enough to demonstrate the touch state detection function, and shortens or eliminates the non-scan time T2 in the scan time Ta so as to prevent unnecessary waiting time.

[0046] The detection unit 32 executes a scan process for detecting a touch state at a scan rate set or reset by the setting unit 30. That is, the detection unit 32 executes the scan process using the signal length of the multiplexed code for touch detection as the signal length of the multiplexed code set or reset by the setting unit 30. The detection unit 32 also executes the scan process using the specified time as the specified time set or reset by the setting unit 30.

[0047] As a scanning process for detecting a touch state, the detection unit 32 first transmits a touch detection signal to each sensor electrode 18y and receives a touch detection signal output from each sensor electrode 18x. Note that, in the second and subsequent scanning processes, the detection unit 32 may perform the scanning process only on an area near the position of the finger F detected previously. Next, the detection unit 32 creates a heat map indicating the detection level for each two-dimensional position on the touch sensor 18 based on the received touch detection signals.

[0048] Next, based on the created heat map, the detection unit 32 determines an area where the change in capacitance formed between the sensor electrode 18x and the sensor electrode 18y is equal to or greater than a threshold, detects the center position of the area as the position of the finger F, and calculates its coordinates. The detection unit 32 then outputs the calculated coordinates to the host processor 22 or the acquisition unit 34. The detection unit 32 may also create frame data including the created heat map and output the frame data to the host processor 22 or the acquisition unit 34.

[0049] Based on the created heat map, the detection unit 32 also performs processing to derive touch areas, which are areas touched by the finger F, and areas touched by the user's palm rather than the finger F. Specifically, the detection unit 32 determines areas where the change in capacitance formed between the sensor electrodes 18x and 18y is equal to or greater than a threshold, and determines the area as a touch area if the area is equal to or less than the threshold, or determines the area as a palm area if not. The detection unit 32 also outputs information indicating the determined touch area and palm area to the host processor 22 and the acquisition unit 34.

[0050] The detection unit 32 waits until a specified time set as the scan time Ta has elapsed before starting the next scan process, and when the specified time has elapsed, repeats the next scan process again.

[0051] The acquisition unit 34 acquires various information to be used for the determination of the determination unit 36. For example, the acquisition unit 34 calculates and acquires information indicating the number of fingers F touching the detection surface 16 and the movement speed of the fingers F based on frame data including the coordinates and heat map of the fingers F output from the detection unit 32. The movement speed of the fingers F is the speed at which the fingers F move along the detection surface 16. Furthermore, the acquisition unit 34 acquires information indicating the touch area and palm area from the output from the detection unit 32.

[0052] In addition, the acquisition unit 34 acquires information indicating the stored state of the electronic pen 14 and information indicating the tilt and movement speed of the electronic pen 14 as information for determining whether or not the non-use state of the electronic pen 14 has been detected.

[0053] Information indicating the stored state of the electronic pen 14 can be obtained, for example, by detecting that the electronic pen 14 has been stored in the electronic device 12 using a sensor or the like and receiving the detected information from the host processor 22. The tilt of the electronic pen 14 indicates the angle between the normal to the detection surface 16 and the axis of the electronic pen 14. Information indicating the tilt of the electronic pen 14 is calculated based on the distance between two pen coordinates obtained based on pen signals transmitted from two transmitting electrodes of the electronic pen 14 that support tilt detection. Information indicating the movement speed of the electronic pen 14 is calculated based on the position coordinates of the electronic pen 14 whose pen state is detected by the pen detection function 28.

[0054] The acquisition unit 34 also acquires information indicating the size of the touch sensor 18 or the number of sensor electrodes 18x, 18y, for example, from the host processor 22. When the touch sensor 18 is disposed overlapping a display panel, the acquisition unit 34 also acquires information indicating the refresh rate of the display panel. The refresh rate is the number of times the display panel is rewritten in a given period of time, and is indicated as, for example, 70 Hz. The acquisition unit 34 acquires the information indicating the refresh rate by receiving it from, for example, the host processor 22.

[0055] Furthermore, when there is a partial area where the user does not intend to touch within the entire area where a touch state can be detected by touch sensor 18, acquisition unit 34 acquires information indicating the existence of the partial area (hereinafter referred to as "non-touch area information"). For example, in the case of a dual-screen model having two screens, touch detection and pen detection are performed on each of the two screens. When acquisition unit 34 receives information indicating that one of the two screens is in an unused mode from host processor 22 or the like, acquisition unit 34 acquires the information as non-touch area information. Furthermore, for example, in the case of a foldable screen configured to be bent, when touch sensor 18 detects that an object such as a keyboard is placed on a partial area of ​​the screen, acquisition unit 34 receives information indicating the state from touch sensor 18 and acquires it as non-touch area information. Furthermore, for example, around a position where one of the screens in a dual-screen model or a partial area of ​​a foldable screen is bent, electronic pen 14 may be detected in multiple areas simultaneously. Therefore, when the acquisition unit 34 determines that there is an area that is closer to a horizontal state based on the tilt of the electronic pen 14 detected by the pen detection function 28, the acquisition unit 34 acquires the determination result as untouched area information.

[0056] The determination unit 36 ​​determines whether or not the determination conditions are satisfied based on, for example, information acquired by the acquisition unit 34. FIG. 7 is a diagram showing an example of a combination of the determination conditions and the scan rates when the determination conditions are satisfied. As shown in FIG. 7, the first conditions indicate, for example, conditions with condition IDs "1" to "6," and the second conditions indicate, for example, conditions with condition IDs "7" and "8." In this embodiment, the determination unit 36 ​​determines that the first condition is satisfied when at least one of the conditions with condition IDs "1" to "6" is satisfied, and determines that the second condition is satisfied when at least one of the conditions with condition IDs "7" and "8" is satisfied.

[0057] Here, "satisfying at least one of a plurality of conditions" means not only satisfying any one of the conditions but also satisfying any combination of the plurality of conditions. Therefore, the determination unit 36 ​​may determine that the first condition is satisfied when any combination of the conditions with condition IDs "1" to "6" is satisfied, not only satisfying any one of these conditions, and may determine that the second condition is satisfied when any combination of the conditions with condition IDs "7" and "8" is satisfied, not only satisfying any one of these conditions.

[0058] The condition with condition ID "1" is a condition for increasing the scan rate as the number of fingers F touching the detection surface 16 decreases. Specifically, the condition with condition ID "1" indicates that when a touch state with one or more fingers F of the user is detected, the number of the fingers F is equal to or less than a threshold value. The threshold value here is set in advance by a designer, operator, etc. as a number that is at least less than the number of fingers F on both hands of the user (10 fingers), and is, for example, the number of fingers F on one hand of the user (5 fingers).

[0059] The determination unit 36 ​​determines whether the condition with condition ID "1" is met based on information indicating the number of fingers F acquired by the acquisition unit 34 as a result of the scan process immediately before the determination. When the number of fingers F is equal to or less than the threshold, the time required to calculate the coordinates of the fingers F is shorter than when the number of fingers F is greater than the threshold. Furthermore, the probability that multiple fingers F will overlap the same electrode is low, and there is a high possibility that electrical noise caused by the touch of the fingers F will be reduced. Therefore, in this case, the length of the code multiplexed signal can be shortened, and the specified time set as the scan time Ta can be shortened. As a result, the scan rate can be increased compared to the reference value.

[0060] The condition with condition ID "2" is a condition for increasing the scan rate when the detection surface 16 is touched not with a finger F but with a palm. Specifically, the condition with condition ID "2" indicates that a touch state with the user's palm has been detected. The determination unit 36 ​​makes a positive determination for the determination of the condition with condition ID "2" when information indicating a palm area is acquired by the acquisition unit 34 as a result of the scan process immediately before the determination. When the palm area is detected, one hand is placed on the detection surface 16, and therefore the number of fingers F touching the detection surface 16 is likely to be small. Therefore, in this case, the scan rate can be increased compared to the reference rate for the same reasons as in the case of the condition with condition ID "1."

[0061] The condition with condition ID "3" is a condition for increasing the scan rate as the moving speed of the finger F decreases. Specifically, the condition with condition ID "3" indicates that when a touch state by the user's finger F is detected, the moving speed of the finger F is equal to or less than a threshold value. Here, the threshold value is preset by a designer, an operator, or the like, for example, 5 mm / sec. The determination unit 36 ​​determines whether the condition with condition ID "3" is satisfied based on information indicating the moving speed of the finger F acquired by the acquisition unit 34 as a result of the scan process immediately before the determination. If the moving speed of the finger F is equal to or less than the threshold value, it can be assumed that the area actually used by the user is small and the detection range is small. Therefore, in this case, the length of the code-multiplexed signal can be shortened, and the specified time set as the scan time Ta can be shortened. As a result, the scan rate can be increased compared to the reference value.

[0062] The condition with condition ID "4" is a condition for increasing the scan rate as the detection range of the touch sensor 18 becomes smaller. Specifically, the condition with condition ID "4" indicates that the size of the touch sensor 18 is equal to or smaller than a threshold value. The threshold value is preset by a designer, operator, or the like as a size corresponding to a small electronic device such as a smartphone or tablet, and is, for example, 11 inches. The determination unit 36 ​​determines whether the condition with condition ID "4" is satisfied based on information indicating the size of the touch sensor 18 acquired by the acquisition unit 34. If the size of the touch sensor 18 is equal to or smaller than the threshold value, the detection range of the touch state is small. Therefore, in this case, the length of the code-multiplexed signal can be shortened, thereby shortening the specified time set as the scan time Ta. As a result, the scan rate can be increased compared to the reference value. Note that the condition with condition ID "4" may indicate that the number of sensor electrodes 18x, 18y is equal to or smaller than a threshold value instead of or in addition to the size of the touch sensor 18.

[0063] The condition with condition ID "5" is a condition for increasing the scan rate as the refresh rate of the display panel on which the touch sensor 18 is disposed increases. Specifically, the condition with condition ID "5" indicates that the refresh rate of the display panel is higher than a threshold value when the touch sensor 18 is disposed on top of the display panel. The threshold value here is set in advance by a designer, operator, or the like as a refresh rate corresponding to the screen display of a game or the like, and is, for example, 120 to 160 Hz. The determination unit 36 ​​determines whether the condition with condition ID "5" is satisfied based on information indicating the refresh rate of the display panel acquired by the acquisition unit 34. If the refresh rate of the screen on which the touch sensor 18 is disposed is higher than the threshold value, the scan rate is increased relative to the reference value to achieve a corresponding scan rate.

[0064] The condition with condition ID "6" is a condition for increasing the scan rate when there is an area within the detection range that is not intended to be touched by the user. Specifically, the condition with condition ID "6" indicates that there is a partial area that is not intended to be touched by the user within the entire area in which a touch state can be detected by the touch sensor 18. When the acquisition unit 34 acquires untouched area information, the determination unit 36 ​​determines that there is a partial area that is not intended to be touched by the user. When there is a partial area that is not intended to be touched by the user, the detection range for the touch state is smaller than when there is no such partial area. Therefore, in this case, the length of the code multiplexed signal can be shortened, and the specified time specified as the scan time Ta can be shortened. As a result, the scan rate can be increased compared to the reference value.

[0065] The condition with condition ID "7" is a condition for lowering the scan rate as the number of fingers F touching the detection surface 16 increases. Specifically, the condition with condition ID "7" indicates that when a touch state with one or more fingers F of the user is detected, the number of the fingers F is equal to or greater than a threshold value. Here, the threshold value is preset by a designer, operator, or the like as a number greater than the number of fingers on one hand of the user (e.g., 6 to 10). The determination unit 36 ​​determines whether the condition with condition ID "7" is satisfied based on information indicating the number of fingers F acquired by the acquisition unit 34 as a result of the scan process immediately before the determination. When the number of fingers F is equal to or greater than the threshold value, the time required to calculate the coordinates of the fingers F increases compared to when the number of fingers F is less than the threshold value. Furthermore, there is a high probability that multiple fingers F will overlap the same electrode, which increases the likelihood of electrical noise caused by the touch of the fingers F. Therefore, in this case, it is necessary to increase the code multiplexing signal length and the specified time set as the scan time Ta. As a result, it is necessary to lower the scan rate compared to the reference value.

[0066] The condition with condition ID "8" is a condition for lowering the scan rate when the pen state is undetectable. Specifically, the condition with condition ID "8" indicates that the unused state of the electronic pen 14 has been detected. The determination unit 36 ​​determines that the unused state of the electronic pen 14 has been detected when the acquisition unit 34 acquires information indicating the stored state of the electronic pen 14. Furthermore, the determination unit 36 ​​determines that the unused state of the electronic pen 14 has been detected when the electronic pen 14 is tilted too much from the horizontal, based on information indicating the tilt of the electronic pen 14 acquired by the acquisition unit 34 as a result of the scan process immediately before the determination. Furthermore, the determination unit 36 ​​determines that the unused state of the electronic pen 14 has been detected when the moving speed of the electronic pen 14 acquired by the acquisition unit 34 as a result of the scan process immediately before the determination is equal to or less than a threshold, based on information indicating the moving speed of the electronic pen 14 acquired by the acquisition unit 34 as a result of the scan process immediately before the determination. When the electronic pen 14 is in the unused state, there is a higher possibility that more fingers F will touch the detection surface 16 than when the electronic pen 14 is in the used state. Therefore, in this case, for the same reason as in the case of condition ID "7", the scan rate must be made higher than the standard.

[0067] The determination unit 36 ​​also determines the processing time for touch detection. For example, the determination unit 36 ​​determines whether a specified time set or reset as the scan time Ta has elapsed, and outputs the determination result to the detection unit 32.

[0068] <Touch IC 20 processing flow> Next, the flow of processing by the touch IC 20 when touch detection is performed by the touch detection function 26 will be described with reference to the flowchart of Fig. 8. Fig. 8 is a flowchart showing an example of the flow of processing by the touch IC 20 when touch detection is performed by the touch detection function 26. Note that the order of the following steps can be changed as appropriate.

[0069] (Step SP14) When touch detection starts, the setting unit 30 initializes the scan rate as a scan setting including the setting of the scan conditions. After proceeding from the processing of step SP24, the setting unit 30 changes and resets the scan rate. Then, the processing proceeds to the processing of step SP16.

[0070] (Step SP16) The detection unit 32 executes a scan process at the scan rate set or reset in the process of step SP14. Specifically, the detection unit 32 transmits touch detection signals to each sensor electrode 18y, receives touch detection signals output from each sensor electrode 18x, and creates a heat map based on the received signals. Then, the process proceeds to the process of step SP18.

[0071] (Step SP18) Based on the heat map created in the process of step SP16, the detection unit 32 calculates the coordinates of the detected finger F. Then, the process proceeds to the process of step SP20.

[0072] (Step SP20) The detection unit 32 outputs the coordinates calculated in the processing of step SP18 to the host processor 22. Then, the processing proceeds to the processing of step SP22.

[0073] (Step SP22) The determination unit 36 ​​determines whether the specified time set or reset as the scan time Ta has elapsed. If the determination is negative, the determination is repeated. If the determination is positive, the process proceeds to step SP24.

[0074] (Step SP24) The determination unit 36 ​​determines whether or not to end the touch detection. If the determination is negative, the process proceeds to step SP14. If the determination is positive, the series of processes shown in FIG. 8 ends.

[0075] FIG. 9 is a flowchart showing an example of the process flow for scan setting in step SP14 of FIG.

[0076] (Step SP26) The determination unit 36 ​​determines whether or not at least any of the conditions of the first condition IDs "1" to "6" is satisfied. If the determination is affirmative, the process proceeds to step SP28. If the determination is negative, the process proceeds to step SP30.

[0077] (Step SP28) The setting unit 30 resets the scan rate to be higher than the reference rate. Specifically, the setting unit 30 shortens the code-multiplexed signal length and resets the specified time determined in the processing of step SP22 so that the reset scan rate is achieved. Then, the scan setting is completed.

[0078] (Step SP30) The determination unit 36 ​​determines whether or not at least one of the conditions of the condition IDs "7" and "8" of the second condition is satisfied. If the determination is affirmative, the process proceeds to step SP32. If the determination is negative, the scan settings are terminated without resetting the scan settings.

[0079] (Step SP32) The setting unit 30 resets the scan rate to a value lower than the reference value and ends the scan setting. Specifically, the setting unit 30 lengthens the code-multiplexed signal length and resets the specified time determined in the processing of step SP22 to be longer so that the reset scan rate is achieved. Then, the scan setting ends.

[0080] <Action and effect> As described above, in the first embodiment, the electronic device 12 includes a capacitive touch sensor 18 having a plurality of sensor electrodes 18x, 18y arranged in a planar shape, and a touch IC 20 connected to the touch sensor 18. The touch IC 20 is a touch state detection circuit IC20 that is connected to the touch sensor 18 and detects a user's touch state by executing a scan process that reads and processes detection signals sequentially output from the sensor electrodes 18x, 18y, and includes a setting unit 30 that sets a scan rate as a scan condition related to the frequency of execution of the scan process, and a detection unit 32 that executes the scan process at the set scan rate to detect a touch state, and when a determination condition indicating a situation in which the scan rate should be changed is satisfied, the setting unit 30 changes and resets the scan rate, and the detection unit 32 detects a touch state at the reset scan rate.

[0081] In addition, the touch state detection method for detecting the user's touch state in this touch IC 20 sequentially repeats a setting step (step SP14) for setting a scan rate and a detection step (steps SP16 to SP24) for performing a scan process at the set scan rate to detect the touch state, and in the setting step, if the judgment conditions are met, the scan rate is changed and reset, and in the detection step, the touch state is detected at the reset scan rate.

[0082] According to the touch IC 20, electronic device 12, and touch state detection method of the first embodiment, the scan rate is changed and reset when the determination conditions are met, so that the scan time Ta can be varied and optimized depending on the detection target, detection range, etc. This ensures that the actual scan time T1 is long enough to perform the touch state detection function, and shortens or eliminates the non-scan time T2 to prevent unnecessary waiting time. As a result, detection can be performed that is suited to various conditions compared to when the scan rate is fixed.

[0083] Furthermore, when a first condition is satisfied as a determination condition, the setting unit 30 resets the scan rate to a higher value than the reference value. The first condition indicates at least one of the conditions with condition IDs "1" to "6" shown in FIG. 7.

[0084] According to this configuration, the scan rate can be increased to shorten the scan time Ta depending on the situation where at least one of the conditions of condition IDs "1" to "6" is satisfied. In particular, for the condition of condition ID "1," the threshold value is set to five, which is the number of fingers F on one hand of the user, so that the scan time Ta can be optimized in distinction from touches with both hands.

[0085] Furthermore, when a second condition is satisfied as a determination condition, the setting unit 30 resets the scan rate to a lower value than the reference scan rate. The second condition indicates at least one of the conditions with condition IDs "7" and "8" shown in FIG. 7.

[0086] According to this configuration, the scan rate can be lowered and the scan time Ta can be increased depending on the situation where at least one of the conditions with condition IDs "7" and "8" is satisfied.

[0087] [Second embodiment] Next, a touch state detection circuit, an electronic device including the touch state detection circuit, and a touch state detection method according to a second embodiment of the present invention will be described with reference to Figures 10 and 11. As with the first embodiment, the touch state detection circuit according to the second embodiment is configured such that an electronic device 12 includes a touch IC 20 which is a touch state detection circuit. Hereinafter, the same reference symbols will be used for configurations or functions that are the same as those in the first embodiment, and descriptions will be omitted as appropriate, and only differences from the first embodiment will be described.

[0088] <Functional configuration of touch IC20> The second embodiment differs from the first embodiment in that the scan condition is a scan condition related to the touch execution cycle, specifically, the scan time Ta, which is the touch execution cycle, rather than a scan rate.

[0089] The setting unit 30 sets the initial value of the scan time Ta to, for example, 10 [mmsec]. When a determination condition indicating a situation in which the scan time Ta, which is a scan condition, should be changed is satisfied, the setting unit 30 changes and resets the scan time Ta. The determination condition includes a first condition indicating a situation in which the scan time Ta should be shortened compared to a reference value, and a second condition indicating a situation in which the scan time Ta should be lengthened compared to the reference value. The reference value here is a reference value of the scan time Ta, which may be, for example, a value set in advance as an initial value, a value set previously immediately before the determination of the determination condition, or the pen scan time. The pen scan time is the scan time required for one scan process to detect the pen state and corresponds to the scan time Ta.

[0090] When the first condition is satisfied, the setting unit 30 shortens the scan time Ta compared to the reference. On the other hand, when it is determined that the second condition is satisfied, the setting unit 30 lengthens the scan time Ta compared to the reference. Note that when the reference is the pen scan time, the change in the scan time Ta may be a change in the scan time Ta relative to the pen scan time by changing the pen scan time. For example, the scan process for detecting the pen state may be stopped and the pen scan time may be set to 0, thereby lengthening the scan time Ta relative to the pen scan time.

[0091] The detection unit 32 performs a scan process for detecting a touch state for the scan time Ta set or reset by the setting unit 30.

[0092] Fig. 10 is a diagram showing an example of a combination of a determination condition according to the second embodiment and a touch execution cycle (scan time Ta) when the determination condition is satisfied, and corresponds to Fig. 7. As shown in Fig. 10, the determination condition according to the second embodiment is the same as the determination condition according to the first embodiment.

[0093] <Touch IC 20 processing flow> In the second embodiment, the processing flow of the touch IC 20 when touch detection is performed by the touch detection function 26 is the same as the flowchart shown in Fig. 8. Also, in the second embodiment, the processing flow of scan setting in step SP14 in Fig. 8 is shown in the flowchart shown in Fig. 11 instead of the flowchart shown in Fig. 9. Fig. 11 is a flowchart showing an example of the processing flow of scan setting in step SP14 in Fig. 8 according to the second embodiment, and corresponds to the flowchart shown in Fig. 9. Note that the order of the following steps can be changed as appropriate.

[0094] (Step SP34) The determination unit 36 ​​determines whether or not at least any of the conditions of the condition IDs "1" to "6" of the first condition is satisfied. If the determination is affirmative, the process proceeds to step SP36. If the determination is negative, the process proceeds to step SP38.

[0095] (Step SP36) The setting unit 30 resets the scan time Ta, which is the touch execution cycle, to be shorter than the reference time, and then ends the scan setting.

[0096] (Step SP38) The determination unit 36 ​​determines whether or not at least one of the conditions of the condition IDs "7" and "8" of the second condition is satisfied. If the determination is affirmative, the process proceeds to step SP40. If the determination is negative, the scan settings are terminated without resetting the scan settings.

[0097] (Step SP40) The setting unit 30 resets the scan time Ta, which is the touch execution cycle, to be longer than the reference time, and ends the scan setting. Then, the scan setting is ended.

[0098] <Action and effect> As described above, in the second embodiment as well, the electronic device 12 includes a capacitive touch sensor 18 formed by arranging a plurality of sensor electrodes 18x, 18y in a planar manner, and a touch IC 20 connected to the touch sensor 18. The touch IC 20 according to the second embodiment includes a setting unit 30 that sets a scan time Ta, which is a touch execution cycle, as a scan condition, and a detection unit 32 that executes a scan process within the set scan time Ta and detects a touch state. When a determination condition indicating a situation in which the scan time Ta should be changed is satisfied, the setting unit 30 changes and resets the scan time Ta, and the detection unit 32 detects a touch state within the reset scan time Ta.

[0099] In addition, the touch state detection method for detecting a user's touch state in the touch IC 20 of the second embodiment sequentially repeats a setting step (step SP14) for setting a scan time Ta, which is a touch execution cycle, and a detection step (steps SP16 to SP24) for executing a scan process using the set scan time Ta to detect the touch state. In the setting step, if the judgment condition is met, the scan time Ta is changed and reset, and in the detection step, the touch state is detected using the reset scan time Ta.

[0100] Therefore, according to the touch IC 20, the electronic device 12, and the touch state detection method according to the second embodiment, the scan time Ta is changed and reset when the determination condition is met, so that the scan time Ta can be varied depending on the detection target, the detection range, etc. As a result, similar to the first embodiment, detection suitable for various conditions can be performed compared to when the scan time Ta is fixed.

[0101] Furthermore, when a first condition is satisfied as a determination condition, the setting unit 30 resets the scan time Ta to be shorter than the reference time. The first condition indicates at least one of the conditions having condition IDs "1" to "6" shown in FIG. 10.

[0102] According to this configuration, the scan time Ta can be shortened depending on the situation where at least one of the conditions of condition IDs "1" to "6" is satisfied. In particular, under the condition of condition ID "1," the threshold is set to five, which is the number of fingers F on one hand of the user, so that the scan time Ta can be optimized in distinction from touches with both hands.

[0103] Furthermore, when a second condition is satisfied as a determination condition, the setting unit 30 resets the scan time Ta to be longer than the reference time. The second condition indicates at least one of the conditions with condition IDs "7" and "8" shown in FIG. 10.

[0104] According to this configuration, the scan time Ta can be lengthened depending on the situation where at least one of the conditions with the condition IDs "7" and "8" is satisfied.

[0105] <Modification> The present invention is not limited to the above-described embodiments. In other words, variations on the above-described embodiments, which are appropriately modified by a person skilled in the art, are also included within the scope of the present invention as long as they incorporate the features of the present invention. Furthermore, the elements of the above-described embodiments and the modifications described below can be combined to the extent technically possible, and such combinations are also included within the scope of the present invention as long as they incorporate the features of the present invention.

[0106] For example, in the first embodiment, an example was described in which both the code-multiplexed signal length and the specified time were changed to achieve a reset scan rate, but this is not limiting. For example, either the code-multiplexed signal length or the specified time may be changed, or other elements may be changed. Furthermore, an example was described in which the scan rate was reset by changing the specified time set as the scan time Ta, but the scan rate may also be reset by changing a specified time set as, for example, an integrated scan time Tb, without being limited to the scan time Ta.

[0107] Furthermore, in the second embodiment, the scan condition related to the touch execution cycle is described as the scan time Ta, but the scan condition related to the touch execution cycle may be the integrated scan time Tb.

[0108] Furthermore, the scan conditions are not limited to control parameters focused only on touch detection, but may also be conditions related to control parameters focused on time-division detection of the pen state and the touch state. For example, the scan conditions may be the ratio of the execution frequency of the scan process for detecting the touch state to the execution frequency of the scan process for detecting the pen state (hereinafter referred to as the "scan execution frequency ratio"). In other words, when the determination conditions are satisfied, the setting unit 30 may change and reset the scan execution frequency ratio.

[0109] FIG. 12 is a diagram for conceptually explaining the ratio of scan execution frequencies. In FIG. 12, of the ten scan processes executed in an arbitrary time ΔT, one scan process in touch detection is indicated by a black square, and one scan process in pen detection is indicated by a white square. Thus, FIG. 12 conceptually illustrates the ratio of the number of scans executed in pen detection to the number of scans executed in touch detection during a predetermined number of scans. (A) of FIG. 12 illustrates a case where the ratio of scan execution frequencies (pen detection:touch detection) is 5:5, and (B) of FIG. 12 illustrates a case where the ratio of scan execution frequencies (pen detection:touch detection) is 6:4. For example, the setting unit 30 changes the ratio of scan execution frequencies from 5:5 shown in (A) of FIG. 12 to 6:4 shown in (B) of FIG. 12. By changing the ratio of scan execution frequencies in this way, the number of scans executed during an arbitrary time ΔT can be changed, even if the scan time Ta required for one scan process is fixed. That is, even if the execution frequency of the scan process in touch detection is fixed, it is possible to change the execution frequency of the global scan process in the overall scan process including the scan process for pen detection and the scan process for touch detection, thereby enabling detection suitable for various conditions.

[0110] Furthermore, the scan condition is not limited to any one of the scan rate, touch execution cycle, and scan execution frequency ratio, but may be a combination of these. In other words, when the determination condition is satisfied, the setting unit 30 may change and reset the scan condition to any combination of the scan rate, touch execution cycle, and scan execution frequency ratio, rather than being limited to any one of these.

[0111] The present invention may also be a program for causing an information processing device such as the touch IC 20 or the electronic device 12 to function as each of the functional configurations shown in Fig. 3. The program may be stored in a storage means disposed inside the touch IC 20 or the electronic device 12, or may be stored in an external storage means connected to the touch IC 20 or the electronic device 12 via a network. The program may also be provided by being recorded on a computer-readable recording medium, or may be provided in a format that allows it to be installed via a network such as the Internet. [Explanation of symbols]

[0112] 18x, 18y: sensor electrodes, 18: touch sensor, 20: touch IC (touch state detection circuit), 30: setting unit, 32: detection unit, F: finger

Claims

1. A touch state detection circuit is connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, and detects a touch state by a user by executing a scan process that reads and processes detection signals sequentially output from each of the sensor electrodes, a setting unit that sets scan conditions related to the execution frequency or execution cycle of the scan process; a detection unit that executes the scan process under the set scan conditions and detects the touch state; Equipped with When a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the setting unit changes and resets the scan conditions so that the execution frequency is higher than a reference or the execution cycle is shorter than a reference, and the detection unit detects the touch state under the reset scan conditions; The determination condition is: a first condition indicating that the touch state by one or more fingers of the user is detected and the number of the fingers is equal to or less than a threshold; a second condition indicating that the touch state by the user's palm has been detected; a third condition indicating that the touch state by the user's finger is detected and the moving speed of the finger is equal to or less than a threshold; a fourth condition indicating that the size of the touch sensor is equal to or smaller than a threshold; or a fifth condition indicating that the touch sensor is disposed over a display panel and that a refresh rate of the display panel is higher than a threshold; Touch state detection circuit.

2. A touch state detection circuit is connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, and detects a touch state by a user by executing a scan process that reads and processes detection signals sequentially output from each of the sensor electrodes, a setting unit that sets scan conditions related to the execution frequency or execution cycle of the scan process; a detection unit that executes the scan process under the set scan conditions and detects the touch state; Equipped with When a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the setting unit changes and resets the scan conditions so that the execution frequency is lower than a reference or the execution cycle is longer than a reference, and the detection unit detects the touch state under the reset scan conditions; The determination condition includes a condition indicating that the touch state by one or more fingers of the user is detected and the number of the fingers is equal to or greater than a threshold value.

3. A touch state detection circuit is connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, and detects a touch state of a user and a pen state of an electronic pen by executing a scan process that reads and processes detection signals sequentially output from each of the sensor electrodes, a setting unit that sets scan conditions related to the execution frequency or execution cycle of the scan process; a detection unit that executes the scan process under the set scan conditions and detects the touch state; Equipped with When a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the setting unit changes and resets the scan conditions so that the execution frequency is lower than a reference or the execution cycle is longer than a reference, and the detection unit detects the touch state under the reset scan conditions; The determination condition includes a condition indicating that a non-use state of the electronic pen has been detected.

4. When the determination condition includes the first condition, the threshold value in the first condition is the number of fingers on one hand of the user, The touch state detection circuit of claim 1 .

5. the determination conditions further include a sixth condition indicating that there is a partial area that the user does not intend to touch within the entire area in which the touch state can be detected by the touch sensor. The touch state detection circuit of claim 1 .

6. the scanning conditions include a ratio of the execution frequency of the scanning process for detecting the touch state to the execution frequency of the scanning process for detecting the pen state of the electronic pen; the detection unit executes the scanning process at the ratio reset by the setting unit to detect the touch state and the pen state in a time-division manner; The touch state detection circuit according to claim 1 or 2.

7. the scanning conditions include a ratio of the execution frequency of the scanning process for detecting the touch state to the execution frequency of the scanning process for detecting the pen state, the detection unit executes the scanning process at the ratio reset by the setting unit to detect the touch state and the pen state in a time-division manner; The touch state detection circuit according to claim 3 .

8. a capacitance type touch sensor having a plurality of sensor electrodes arranged in a plane; a touch state detection circuit according to any one of claims 1 to 3, connected to the touch sensor; An electronic device comprising:

9. A touch state detection method is carried out by a detection circuit connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, the detection circuit detecting a user's touch state by executing a scan process that reads and processes detection signals sequentially output from each of the sensor electrodes, a setting step of setting a scan condition related to an execution frequency or an execution cycle of the scan process; a detection step of detecting the touch state by executing the scan process under the set scan conditions; Repeat the steps in order, In the setting step, when a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the scan conditions are changed and reset so that the execution frequency is higher than a reference or the execution cycle is shorter than a reference, and in the detection step, the touch state is detected under the reset scan conditions; The determination condition is: a first condition indicating that the touch state by one or more fingers of the user is detected and the number of the fingers is equal to or less than a threshold; a second condition indicating that the touch state by the user's palm has been detected; a third condition indicating that the touch state by the user's finger is detected and the moving speed of the finger is equal to or less than a threshold; a fourth condition indicating that the size of the touch sensor is equal to or smaller than a threshold; or a fifth condition indicating that the touch sensor is disposed over a display panel and that a refresh rate of the display panel is higher than a threshold; Touch state detection method.

10. A touch state detection method is carried out by a detection circuit connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, the detection circuit detecting a user's touch state by executing a scan process that reads and processes detection signals sequentially output from each of the sensor electrodes, a setting step of setting a scan condition related to an execution frequency or an execution cycle of the scan process; a detection step of detecting the touch state by executing the scan process under the set scan conditions; Repeat the steps in order, In the setting step, when a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the scan conditions are changed and reset so that the execution frequency is lower than a reference or the execution cycle is longer than a reference, and in the detection step, the touch state is detected under the reset scan conditions; The touch state detection method, wherein the determination condition includes a condition indicating that the touch state by one or more fingers of the user is detected and the number of the fingers is equal to or greater than a threshold.

11. A touch state detection method is carried out by a detection circuit connected to a capacitive touch sensor having a plurality of sensor electrodes arranged in a plane, and detecting a touch state of a user and a pen state of an electronic pen by executing a scanning process that reads and processes detection signals sequentially output from each of the sensor electrodes, a setting step of setting a scan condition related to an execution frequency or an execution cycle of the scan process; a detection step of detecting the touch state by executing the scan process under the set scan conditions; Repeat the steps in order, In the setting step, when a determination condition indicating a situation in which the scan conditions should be changed is satisfied, the scan conditions are changed and reset so that the execution frequency is lower than a reference or the execution cycle is longer than a reference, and in the detection step, the touch state is detected under the reset scan conditions; The touch state detection method, wherein the determination condition includes a condition indicating that a non-use state of the electronic pen has been detected.

12. When the determination condition includes the first condition, the threshold value in the first condition is the number of fingers on one hand of the user, The touch state detection method according to claim 9 .

13. the determination condition further includes a condition indicating that there is a partial area that the user does not intend to touch within the entire area in which the touch state can be detected by the touch sensor. The touch state detection method according to claim 9 .

14. the scanning conditions include a ratio of the execution frequency of the scanning process for detecting the touch state to the execution frequency of the scanning process for detecting the pen state of the electronic pen; In the detecting step, the scanning process is executed at the reset ratio to detect the touch state and the pen state in a time-division manner. The touch state detection method according to claim 9 or 10.

15. the scanning conditions include a ratio of the execution frequency of the scanning process for detecting the touch state to the execution frequency of the scanning process for detecting the pen state, In the detecting step, the scanning process is executed at the reset ratio to detect the touch state and the pen state in a time-division manner. The touch state detection method of claim 11.

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