TWI514212B - Touch panel capable of detecting a stylus and a method of using the same - Google Patents

Description

Touch panel capable of detecting stylus and using method thereof

The present invention relates to a touch panel, and more particularly to a touch panel capable of detecting a stylus.

The stylus is an auxiliary tool for touch screens. The tip of the stylus is so small that it is difficult to be sensed by a typical touch screen. Therefore, when using a general touch screen, a specially manufactured capacitive stylus is usually required.

However, traditional styluses (such as capacitive styluses) require considerable processing and cost. Furthermore, capacitive stylus is not easy to replace immediately when it is faulty, forgotten or lost.

Therefore, there is a need to propose a novel mechanism for detecting styluses (especially non-specially manufactured styluses), providing more convenience to users of general touch screens.

In view of the above, one of the objects of the embodiments of the present invention is to provide a touch panel and a method thereof, which are more efficient and more accurate than conventional touch panels.

According to an embodiment of the invention, a touch panel capable of detecting a stylus includes a plurality of electrode columns disposed along a first axial direction and a plurality of electrode rows disposed along a second axial direction. The intersection of each electrode column and the electrode row has mutual capacitance, and each electrode column and each electrode row have a self-capacitance. A voltage is applied to the electrode row or the electrode column during a self-scanning cycle, and the same electrode row or electrode column is measured to detect the stylus that touches the surface of the touch panel. A voltage is applied to an axial direction during an inter-scan period, and another axial direction is measured to detect a stylus that touches the surface of the touch panel. During each scan frame, at least one self-scan period and at least one mutual scan period are performed, and when the self-scan period and the mutual scan period are detected, the touch recognition of the stylus is performed. be confirmed.

The first figure shows a schematic diagram of a touch panel 100 according to an embodiment of the present invention. The touch panel 100 of the present embodiment can be applied to an electronic device such as a mobile phone. The touch panel 100 (for example, a capacitive touch panel) is composed of an electrode array 11 and an electrode row 12. Each of the electrode columns 11 and the electrode row 12 has a mutual capacitance C _m ; and each of the electrode columns 11 and each electrode row 12 has a selfcapacitance C _s . The touch panel 100 of the present embodiment can detect the stylus more efficiently and correctly than the conventional touch panel to perform related functions. The stylus referred to in this embodiment can generally refer to a stylus which is generally not specially manufactured or capacitive.

Continuing to refer to the first figure, for the self-capacitance C _s , a voltage is applied to the electrode row 12 or the electrode column 11 during the self-scan period, and the same electrode row 12 is measured by a detecting circuit (not shown). Or the electrode array 11 to detect a stylus that touches the front side (or the touch surface) of the touch panel 100. For the mutual capacitance C _m , a voltage is applied to one axis (for example, the electrode row 12) during the mutual scan period, and another axis (for example, the electrode column 11) is measured by the detecting circuit to detect the touch. The stylus of the control panel 100.

The schematic of the second diagram illustrates a scan (or measurement) scan frame sequence. According to one of the features of the embodiment, a complex number (as for the ten illustrated in the second figure) of the previous scan frame (related to the self-capacitance C _s ) can be accumulated from the self raw data. Since the intensity of the original data obtained by the stylus during detection is usually weak, the touch sensitivity can be enhanced by accumulating the original information of the scanning frame.

According to another feature of the embodiment, referring to the second figure, in each scan frame, a plurality of self-scan cycles (such as the two illustrated in the second figure) are executed, and then The self-scanning raw materials of the self-scanning cycle are summed up. Thereby, the total self-original data can enhance the touch sensitivity of the touch panel 100.

According to still another feature of the embodiment, referring to the second figure, in addition to performing one or more self-scanning cycles, each scan frame performs at least one mutual scan cycle, such as The two figures are illustrated. The mutual raw data of the mutual scanning cycle (related to the mutual capacitance _Cm ) can be used to confirm that the stylus touches the surface of the touch panel 100. For example, in this embodiment, the touch recognition is confirmed only when both the self-scan period and the mutual scan period are detected. In other words, in this embodiment, if one of the self-scanning period or the inter-scanning period is not detected, the touch recognition is not confirmed. Simultaneous execution of the self-scanning cycle and the mutual scanning cycle can be used to prevent the influence of the surrounding environment change on the touch panel 100.

In the present embodiment, as shown in FIG. A third, For the self-capacitance C _s, when the data from the original greater than a predetermined (or a self-scanning period) from the touch threshold value TH _s, touching only identified It is detected. As shown in FIG. B, for the mutual capacitance C _m , when the mutual original data (at least one mutual scanning period) is greater than the preset mutual touch threshold TH _m , the touch recognition is detected.

The fourth figure shows a flow chart of the touch action of the recognition stylus according to the embodiment of the present invention. In step 41, the self-origin data from the capacitance C _{s is} compared with the self-touch threshold TH _s (in one or more self-scanning cycles of the scan frame). If the result of step 41 is negative (i.e., greater than from the original data from the non-touch threshold value TH _s), the touch operation is ignored (step 42). Otherwise, the process proceeds to step 43, and the mutual raw data corresponding to the mutual capacitance C _m (scanning frame) is compared with the mutual touch threshold value TH _m . If the result of step 43 is negative (i.e., the mutual original data is not greater than the mutual touch threshold TH _m ), the touch action is ignored (step 44); otherwise, at step 45, the count value is incremented. If the count value is not greater than the set value ("no" branch path of step 46), then the flow returns to step 41 to process the next scan frame. If the count value is greater than the set value ("YES" branch path of step 46), the touch action is recognized and the touch panel 100 enters the stylus mode (step 47). As shown in the third A diagram or the third B diagram, the count value is used in conjunction with the set value to prevent false touch recognition caused by unstable original data. In this embodiment, as shown in the fourth figure, the touch action is truly recognized only after the original data is stabilized (that is, the original data is greater than the touch threshold by a preset number of times). After entering the stylus mode (in other words, after leaving the finger mode), some parameters need to be adjusted. For example, increasing the original data is greater than the preset number of touch thresholds to enhance the accuracy of the touch recognition. Furthermore, in the stylus mode, the localized algorithm is recognized by a single touch, not by the multi-touch in the finger mode.

The fifth figure shows a flow chart of releasing the touch action of the stylus (away from the stylus mode) in the embodiment of the present invention. In step 51, the self-origin data from the capacitance C _{s is} compared with the self-touch threshold TH _s (in one or more self-scanning cycles of the scan frame). If the original data is not less than the self-touch threshold TH _s , the original data is ignored (step 52). Otherwise, the process proceeds to step 53 to compare the mutual original data corresponding to the mutual capacitance C _m (scanning frame) with the mutual touch threshold value TH _m . If the mutual original data is not less than the mutual touch threshold TH _m , the mutual original data is ignored (step 54); otherwise, in step 55, the count value is incremented. If the count value is not greater than the set value ("no" branch path of step 56), then the flow returns to step 51 to process the next scan frame. If the count value is greater than the set value ("YES" branch path of step 56), the touch action is released and the touch panel 100 leaves the stylus mode (step 57). As shown in the third A diagram or the third B diagram, the count value is used in conjunction with the set value to prevent the erroneous touch release due to the unstable original data. In this embodiment, as shown in the fifth figure, the touch action is actually cancelled only after the original data is stabilized (that is, the original data is less than the touch threshold reaches a preset number of times).

The sixth figure shows a flow chart of releasing the touch action of the stylus (away from the stylus mode) according to another embodiment of the present invention. In step 61, the mutual original data corresponding to the mutual capacitance C _m (in the scanning cycle) is compared with the mutual threshold TH associated with the finger touch of the finger mode. The mutual threshold TH associated with the above finger touch is generally greater than the mutual touch threshold TH _m associated with the stylus touch of the stylus mode. If the mutual original data is not greater than the mutual threshold TH, the mutual original data is ignored (step 62). Otherwise, if the mutual original data is greater than the mutual threshold TH, indicating that the finger touches the touch panel 100, the touch action of the stylus is released and the touch panel 100 leaves the stylus mode (step 63).

The above description is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention; all other equivalent changes or modifications which are not departing from the spirit of the invention should be included in the following Within the scope of the patent application.

100‧‧‧ touch panel

11‧‧‧electrode column
12‧‧‧electrode row
41~47‧‧‧Steps to recognize the touch action of the stylus
51~57‧‧‧Steps to remove the touch action of the stylus
61~63‧‧‧Steps to remove the touch action of the stylus
C _s ‧‧‧Self capacitance
C _m ‧‧‧ mutual capacitance
TH _s ‧‧‧self-touch threshold
TH _m ‧‧‧ mutual touch threshold
TH‧‧‧ Mutual Threshold

The first figure shows a schematic diagram of a touch panel according to an embodiment of the invention. The schematic of the second figure illustrates a scan frame sequence. The third A picture shows the threshold value from the original data relative to the preset self-touch. The third B graph shows the threshold value of the mutual original data relative to the preset mutual touch. The fourth figure shows a flow chart of the touch action of the recognition stylus according to the embodiment of the present invention. The fifth figure shows a flow chart of releasing the touch action of the stylus according to the embodiment of the present invention. The sixth figure shows a flow chart of releasing the touch action of the stylus according to another embodiment of the present invention.

41~47‧‧‧Steps to recognize the touch action of the stylus

Claims (14)

A touch panel capable of detecting a stylus comprises: a plurality of electrode columns disposed along a first axial direction; and a plurality of electrode rows disposed along a second axis, each of the electrode columns and the electrode rows having mutual capacitance And each electrode column and each electrode row has a self-capacitance; wherein a voltage is applied to the electrode row or the electrode column during a self-scanning period, and the same electrode row or electrode column is measured to detect the touch a stylus that touches the surface of the touch panel; applies a voltage to an axis during a mutual scanning period, and measures another axis to detect a stylus that touches the surface of the touch panel; The at least one self-scanning period and the at least one mutual scanning period are performed in each of the scanning frames, and the values obtained by the self-scanning period and the values obtained by the mutual scanning period are detected. The touch recognition of the stylus will be confirmed; in each scan frame, the same self-scan cycle is executed, and the self-scan original data of the self-scan cycles are summed. According to the first aspect of the patent application, the touch panel of the stylus can be detected, wherein self-data related to the self-capacitance of the plurality of previous scan frames is accumulated. According to the first aspect of the patent application, the touch panel of the stylus can be detected, wherein in the scan frame, when the original data is greater than the preset self-touch threshold, and the mutual original data is greater than the preset mutual touch The touch recognition of the stylus will be confirmed when the threshold is touched. According to the first aspect of the patent application, the touch panel of the stylus can be detected, wherein in the scan frame, when the original data is smaller than the preset self-touch threshold, and the mutual original data is smaller than the preset mutual touch When the threshold is touched, the touch action of the stylus will be released. According to the scope of claim 1, the touch panel of the stylus can be detected, wherein in the scanning frame, when the mutual original data is greater than the preset mutual threshold value related to the finger touch, the touch of the stylus The touch action will be released. According to the first aspect of the patent application, the touch panel of the stylus can be detected, wherein when the self-original data related to the self-capacitance and the mutual original data related to the mutual capacitance are stabilized, the touch recognition of the stylus is Will be confirmed. According to the scope of claim 1, the touch panel of the stylus can be detected, wherein when the self-original data related to the self-capacitance and the mutual original data related to the mutual capacitance are stabilized, the touch action of the stylus is Will be lifted. A method for detecting a stylus using a touch panel, comprising: providing a plurality of electrode columns disposed along a first axial direction; providing a plurality of electrode rows disposed along a second axial direction, an intersection of each electrode column and the electrode rows Each of the electrode columns and each of the electrode rows has a self-capacitance; a voltage is applied to the electrode row or the electrode column during a self-scanning cycle, and the same electrode row or electrode column is measured to detect a stylus that touches the surface of the touch panel; applies a voltage to an axis during a mutual scanning period, and measures another axis to detect a stylus that touches the surface of the touch panel And performing at least one self-scanning period and at least one mutual scanning period in each of the scanning frames, and the values obtained by the self-scanning period and the values obtained by the mutual scanning period are detected. At that time, the touch recognition of the stylus will be confirmed; wherein each of the scan frames performs the same self-scan cycle; and the self-scan original data of the self-scan cycles are summed up. . According to the method of claim 8, the method of using the touch panel to detect the stylus further includes a step of accumulating self-data related to the self-capacitance of the plurality of previous scan frames. According to the method of claim 8, the method of using the touch panel to detect the stylus, wherein in the scan frame, when the original data is greater than the preset self-touch threshold, and the mutual original data is greater than the preset The touch recognition of the stylus will be confirmed when the threshold is touched. According to the method of claim 8, the method of using the touch panel to detect the stylus, wherein in the scan frame, when the original data is smaller than the preset self-touch threshold, and the mutual original data is smaller than the preset When the threshold is touched, the touch action of the stylus will be released. The method of using a touch panel to detect a stylus according to claim 8 of the patent application, wherein in the scanning frame, when the mutual original data is greater than a preset mutual threshold value related to the finger touch, the stylus The touch action will be released. The method of using a touch panel to detect a stylus according to claim 8 of the patent application scope, wherein the stylus touches after the self-original data related to the self-capacitance and the mutual original data related to the mutual capacitance are stabilized Identification will be confirmed. The method of using a touch panel to detect a stylus according to claim 8 of the patent application scope, wherein the stylus touches after the self-original data related to the self-capacitance and the mutual original data related to the mutual capacitance are stabilized The action will be released.