Abstract:
A dual-mode touch sensing method adapted for a stylus and a touch panel comprising N first signal lines and M second signal lines. The method comprises: sequentially controlling the N first signal lines to emit N corresponding pulse signals in N gesture periods in a scanning period, receiving M gesture feedback signals corresponding to the pulse signals via the M second signal lines in each among the N gesture periods, selectively generating a gesture signal based on the gesture feedback signals, determining a stylus period other than the N gesture periods in the scanning period by the stylus, generating a stylus signal in the stylus period by the stylus, and receiving the stylus signal and generating a stylus touching signal accordingly by the touch panel.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 104124575 filed in Taiwan, R.O.C. on Jul. 29, 2015, the entire contents of which are hereby incorporated by reference. 
       TECHNICAL FIELD 
       [0002]    This disclosure is related to a touch sensing method and stylus and touch panel applicable for the method, and particularly related to a dual-mode touch sensing method and stylus and touch panel applicable for the method. 
       BACKGROUND 
       [0003]    The touch sensing technology is applied in a variety of electronic devices since the touch sensing technology was developed. In early years, a stylus is used as an input mechanism in this field, and then gesture sensing is developed. In recent years, the stylus and the gesture sensing can be integrated so that the dual-mode input is a common means of touch sensing in many electronic devices. 
         [0004]    However, there is an obstacle of false-sensing in the dual-mode input mechanism. If an electronic device recognizes an input by a stylus when the user of the electronic device is actually input command with his/her finger, vice versa, this situation is called false-sensing. Hence, it is an issue to be conquered that how an electronic device tells a gesture input from a stylus input when a user controls the electronic device with these two ways meanwhile. 
       SUMMARY 
       [0005]    A dual-mode touch sensing method in one embodiment of the disclosure is applicable for a stylus and a touch panel having N first signal lines and M second signal lines, and the method includes the steps of: sequentially controlling the N first signal lines to emit N corresponding pulse signals within N gesture periods in a scanning period, receiving M corresponding gesture feedback signals by the M second signal lines within each of the N gesture periods, selectively generating a gesture signal according to the gesture feedback signals, determining at least one stylus period other than the gesture periods in the scanning period according to the N pulse signals by the at least one stylus, emitting a stylus signal by the at least one stylus in the stylus period, and receiving the stylus signal to generate a stylus touching signal by the touch panel. 
         [0006]    According to one embodiment of the disclosure, the stylus comprises: a wireless receiving module for wirelessly receiving at least one pulse signal from a touch panel; a processing module electrically connected to the wireless receiving module, for determining a stylus period corresponding to the touch panel according to the at least one pulse signal, and selectively generating a stylus signal during the stylus period; and a wireless transmitting module electrically connected to the processing module and for emitting the stylus signal. 
         [0007]    According to one embodiment of the disclosure, the touch panel comprises: N first signal lines; M second signal lines, overlapping with and not connected to the N first signal lines; and a touch processing module, respectively electrically connected to the N first signal lines and the M second signal lines, for sequentially controlling the N first signal lines to emit N corresponding pulse signals during N gesture periods in a scanning period, and selectively generating a gesture signal according to M gesture feedback signals received by the M second signal lines, and controlling the N first signal lines and the M second signal lines to receive a stylus signal during each of N stylus periods in the scanning period, and selectively generating a stylus touching signal according to at least one stylus feedback signal corresponding to the stylus signal; wherein ith gesture period among the N gesture period is timing adjacent to ith stylus period among the N stylus periods; wherein M and N are both integers larger than one, and i is a positive integer less than or equal to N. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The present disclosure will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only and thus are not limitative of the present disclosure and wherein: 
           [0009]      FIG. 1  is a part of the diagram illustrating the touch panel according to one embodiment of the disclosure; 
           [0010]      FIG. 2  is a block diagram of a stylus according to one embodiment of the disclosure; 
           [0011]      FIG. 3  is a signal timing diagram according to one embodiment of the disclosure; 
           [0012]      FIG. 4  is a signal timing diagram according to another embodiment of the disclosure; and 
           [0013]      FIG. 5  is a flowchart of the dual-mode touch sensing method according to one embodiment of the disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing. 
         [0015]    Please refer to  FIG. 1  and  FIG. 2 , wherein  FIG. 1  illustrates a portion of a touch panel according to one embodiment of the disclosure, and  FIG. 2  illustrates a functional block diagram of a stylus according to one embodiment of the disclosure. As shown in  FIG. 1 , the touch panel  100  includes N first signal lines  111 ˜ 11 N, M second signal lines  121 ˜ 12 M, and a touch processing module  130 . It is understood according to  FIG. 1  that N and M are integers larger than one. The first signal lines are not parallel to the second signal lines and overlapping over the second signal lines. The touch processing module  130  is respectively electrically connected to the N first signal lines  111 ˜ 11 N and the M second signal lines  121 ˜ 12 M, and the first signal lines are not directly connected to the second signal lines. As shown in  FIG. 2 , the stylus  200  includes a wireless receiving module  210 , a processing module  220 , and a wireless transmitting module  230 . The processing module  220  is respectively electrically connected to the wireless receiving module  210  and the wireless transmitting module  230 . In certain embodiments, the wireless receiving module  210  and the wireless transmitting module  230  is integrated as a wireless transceiver. 
         [0016]    Please refer to  FIG. 3 , which illustrates a timing diagram of signals according to one embodiment of the disclosure. As shown in  FIG. 3 , the scanning period Tscan is defined as a period the touch panel  100  scanning a touch of a user&#39;s finger and/or a touch by the stylus  200 . In one embodiment, a scanning period Tscan is divided into a stylus period Tsty and N gesture period, denoted from T 1  to TN. In the gesture period T 1 , the touch processing module  130  controls the first signal lines  111  to transmit at least one pulse signal, so the voltage V 111  on the first signal line  111  varies during the gesture period T 1 . Meanwhile, the touch processing module  130  controls the M second signal lines  121 ˜ 12 M to respectively receive the gesture feedback signals corresponding to the at least one pulse signal so that the voltage VRX on the second signal lines also varies. Specifically, the gesture feedback signal when the touch panel  100  is touched by a finger is different from the gesture feedback signal when the touch panel  100  is not touched by the finger. Hence, the touch processing module  130  is capable of determining whether at least one cross-section among the M cross-sections between the first signal lines  111  and the second signal lines  121 ˜ 12 M is touched by a user&#39;s finger or any other object. During the gesture period T 1  through the gesture period TN, the touch processing module  130  performs the same functionality. Hence, if the touch processing module  130  determines the second signal line  12   q  is touched by a finger during the gesture period Tk, it means that the cross-section between the first signal line  11   k  and the second signal line  12   q  is touched by the finger. 
         [0017]    In the embodiment, there is a stylus period Tsty after the gesture period TN. In the at least one pulse signal emitted by the first signal line  111  in the gesture period T 1  includes information about when this pulse signal is generated. For example, the at least one pulse signal emitted by the first signal line  111  is decoded so that a flag 0x1 is obtained. Similarly, the at least one pulse signal emitted by the first signal line  11 N is decoded so that a flag 0xN is obtained. Hence, if the stylus  200  is close to the first line  11   k  the most, the processing module  220  decodes a pulse signal after the pulse signal is received by the wireless receiving module  210  and the flag 0xk is obtained. After the processing module  220  decodes to obtain the flag 0xk for several times, the processing module  220  is capable of obtaining a length of a scanning period Tscan according to a period between two adjacent flags 0xk. After the length of the scanning period Tscan is determined, the processing module  220  is capable of obtaining a timing difference between the stylus period Tsty and the gesture period Tk. Hence, in the stylus period Tsty, the processing module  220  controls the wireless transmitting module  230  to emit the stylus signal. Hence, the voltage Vsty varies during the stylus period Tsty. 
         [0018]    In another embodiment, the at least one pulse signal emitted by each of the first signal lines is embedded with a timing difference information corresponding to the pulse signal and the stylus period Tsty. For example, assume that N equals to 100, and the length of a scanning period Tscan is 9 ms, and the length of each gesture period is 80 us. The timing difference between the gesture period T 1  and the stylus period Tsty is 7.92 ms. The pulse signal emitted by the first signal line  111  is embedded with this information, so the processing module  220  decodes the pulse signal received by the wireless receiving module  210  to obtain this timing information. 7.92 ms latter, the processing module  220  controls the wireless transmitting module  230  to emit the stylus signal. The stylus signal is identical or inverse to the pulse signal emitted by the first signal line  11 N. 
         [0019]    In yet another embodiment, there is a prompt period between the Nth gesture period TN and the stylus period Tsty. During the prompt period, the touch processing module  130  controls each of the first signal lines to emit the prompt signal. When the wireless receiving module  210  in the stylus  200  receives the prompt signal, the processing module  220  controls the wireless transmitting module  230  to emit the stylus signal. In one embodiment, the prompt signal is embedded with information about a length of the stylus period, so the processing module  220  controls the wireless transmitting module  230  to emit the stylus signal precisely during the stylus period Tsty. 
         [0020]    In one embodiment, during the stylus period Tsty, the first signal lines  111  through  11 N are not emitting the pulse signal(s), but the first signal lines are not switched to receive the pulse signal. The second signal lines  121  through  12 M are still enabled to receive the pulse signal and/or the stylus signal. In other words, the first signal lines are used for emitting the pulse signal and the second signal lines are used for receiving the sensed pulse signal, during the gesture period. During the stylus period, the first signal lines and the second signal lines may both be used for receiving the stylus signal. Otherwise, only the second signal lines  121  through  12 M are used for receiving the stylus signal. If both the first signal line  11   i  and the second signal line  12   j  receive the stylus signal, the touch processing module  130  determines the position of the stylus  200  is on the cross-section between the first signal line  11   i  and the second signal line  12   j , and the stylus touching signal is generated therefore. In another embodiment, the touch processing module  130  collects (M+N) stylus feedback signal from the first signal lines  111  through  11 N and the second signal lines  121  through  12 M, and determines the position of the stylus  200  according to the intensity of each of the stylus feedback signal. 
         [0021]    In yet another embodiment, the stylus signal is embedded with further control information such as texture of drawing lines, the width of drawing lines, etc. The touch processing module  130  embedded those control information and the piece of position information of the stylus  200  into the stylus touching signal. 
         [0022]    In still another embodiment, please refer back to  FIG. 2 , the stylus  200  further includes an actuator  240  electrically connected to the processing module  220 ∘ The actuator  240  is, for example, a button, and has a first state (released) and a second state (pressed). The processing module  220  does not generate the stylus signal when the actuator  240  is in the first state. Otherwise, the processing module  220  generates the stylus signal. 
         [0023]    In one embodiment, please refer to  FIG. 4 , which illustrates a signal timing diagram according to another embodiment of the disclosure. As shown in  FIG. 4 , a scanning period Tscan is divided into a stylus period Tsty and N gesture period, denoted from T 1  to TN. In the gesture period T 1 , the touch processing module  130  controls the first signal lines  111  to transmit at least one pulse signal, so the voltage V 111  on the first signal line  111  varies during the gesture period T 1 . Meanwhile, the touch processing module  130  controls the M second signal lines  121 ˜ 12 M to respectively receive the gesture feedback signals corresponding to the at least one pulse signal so that the voltage VRX on the second signal lines also varies. Specifically, the gesture feedback signal when the touch panel  100  is touched by a finger is different from the gesture feedback signal when the touch panel  100  is not touched by the finger. Hence, the touch processing module  130  is capable of determining whether at least one cross-section among the M cross-sections between the first signal lines  111  and the second signal lines  121 ˜ 12 M is touched by a user&#39;s finger or any other object. During the gesture period T 1  through the gesture period TN, the touch processing module  130  performs the same functionality. Hence, if the touch processing module  130  determines the second signal line  12   q  is touched by a finger during the gesture period Tk, it means that the cross-section between the first signal line  11   k  and the second signal line  12   q  is touched by the finger. 
         [0024]    In the embodiment, there is a stylus period Tsty 1  between the gesture period T 1  and the gesture period T 2 . Similarly, the ith stylus period is timing adjacent to the ith gesture period. If the stylus  200  is located between the first signal line  111  and the first signal line  112 , the processing module  220  would determine that there is a stylus period Tsty 1  between the gesture period T 1  and T 2  after the stylus  200  receives the pulse signal emitted by the first signal line  111  and  112  for several times. The processing module  220  then controls the wireless transmitting module  230  to emit the stylus signal during the stylus period Tsty 1 . 
         [0025]    The touch processing module  130  of the touch panel  100  then collects M stylus feedback signal from the second signal lines during each of the N stylus period. The touch processing module  130  then determines the position of the stylus  200  according to the intensity of each of the M×N stylus feedback signal. In the embodiment, if there is no stylus signal received, the intensity of the stylus feedback signal is set to be zero. 
         [0026]    In one embodiment, during the stylus period Tsty 1 , the first signal lines  111  through  11 N are disabled so they neither emit the pulse signal nor used for receiving the stylus signal. The second signal lines  121  through  12 M are still enabled to receive the stylus signal. In other words, during the gesture period(s), the first signal lines are used for emitting the pulse signal and the second signal lines are used for receiving the sensed pulse signal. During the stylus period(s), the first signal lines are disabled so as to reduce the power consumption, and the second signal lines are used for receiving the stylus signal from the stylus  200 . 
         [0027]    Please refer to  FIG. 1 ,  FIG. 2 , and  FIG. 5  for understanding a dual-mode touch sensing method according to one embodiment of the disclosure, wherein  FIG. 5  illustrates a flowchart of the dual-mode touch sensing method according to one embodiment of the disclosure. As shown in step S 100 , the touch processing module  130  of the touch panel  100  sequentially controls the N first signal lines  111  through  11 N to emit N corresponding pulse signals during N gesture periods in a scanning period. As shown in step S 200 , receiving M gesture feedback signals corresponding to the pulse signals via the M second signal lines in each among the N gesture periods. As shown in step S 300 , the touch processing module  130  selectively generates a gesture signal according to the gesture feedback signals. As shown in step S 400 , the stylus  200  determines at least one stylus period in the scanning period and other than the N gesture periods according to the N pulse signals. As shown in step S 500 , the stylus  200  emits a stylus signal during the stylus period. As shown in step S 600 , the stylus signal is received by the second signal lines and/or the first signal lines of the touch panel  100  so as to generate the stylus touching signal. 
         [0028]    As above, the method, stylus, and touch panel according to one or more embodiment of the disclosure provides that the stylus period for sensing the stylus signal is determined by the touch panel. The stylus obtains the stylus period according to the pulse signal emitted from the touch panel so as to emit the stylus signal during the stylus period. Hence, the touch panel is prevented from false-sensing a finger touch as a stylus input, or vise versa.