CN104423750B - Touch panel capable of detecting stylus and use method thereof - Google Patents

Abstract

A touch panel capable of detecting a stylus pen and a method of using the same. The touch panel capable of detecting a stylus pen executes at least one self-scanning cycle and at least one mutual scanning cycle in each scanning frame, and the touch recognition of the stylus pen is confirmed only when both the self-scanning cycle and the mutual scanning cycle are detected.

Description

Touch panel capable of detecting stylus and method of use thereof

technical field

The present invention relates to a touch panel, in particular to a touch panel capable of detecting a stylus.

Background technique

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

However, traditional stylus (such as capacitive stylus) requires considerable manufacturing process and cost. Furthermore, when encountering failure, forgetting or losing, the capacitive stylus is not easy to replace immediately.

Therefore, it is urgent to propose a novel mechanism to detect the stylus (especially the non-specially manufactured stylus), so as to provide more convenience to the general touch screen users.

Contents of the invention

In view of the above, one of the objectives of the embodiments of the present invention is to provide a touch panel and its method, which can detect the stylus more efficiently and accurately than the traditional touch panel.

According to an embodiment of the present invention, the touch panel capable of detecting a stylus includes a plurality of electrode rows arranged along a first axis, and a plurality of electrode columns arranged along a second axis. The intersection of each electrode row and electrode column has a mutual capacitance, and each electrode row and each electrode column has a self-capacitance. A voltage is applied to the electrode row or the electrode row in a self-scanning period, and then the same electrode row or electrode row is measured to detect the stylus touching the surface of the touch panel. A voltage is applied to one axis in a mutual scan period, and then the other axis is measured to detect the stylus touching the surface of the touch panel. In each scanning frame, at least one self-scanning period and at least one inter-scanning period are performed, and when both the self-scanning period and the inter-scanning period are detected, the touch recognition of the stylus is confirmed.

Description of drawings

FIG. 1 shows a schematic diagram of a touch panel according to an embodiment of the present invention.

Figure 2 is a schematic diagram illustrating a scan frame sequence.

Figure 3A shows self-raw data versus preset self-touch thresholds.

Figure 3B shows mutual raw data versus preset mutual touch thresholds.

FIG. 4 shows a flowchart of recognizing a touch action of a stylus according to an embodiment of the present invention.

FIG. 5 shows a flow chart of releasing the touch action of the stylus according to an embodiment of the present invention.

FIG. 6 shows a flow chart of releasing the touch action of the stylus according to another embodiment of the present invention.

Description of reference symbols

100 touch panel

11 electrode rows

12 electrode columns

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

51~57 Steps to cancel the touch action of the stylus

61~63 Steps to cancel the touch action of the stylus

C _s self capacitance

C _m mutual capacitance

TH _s self-touch threshold

TH _m mutual contact threshold

TH mutual threshold

Detailed ways

FIG. 1 shows a schematic diagram of a touch panel 100 according to an embodiment of the present invention. The touch panel 100 of this embodiment can be applied to electronic devices, such as mobile phones. The touch panel 100 (such as a capacitive touch panel) is composed of electrode rows 11 and electrode columns 12 . The intersection of each electrode row 11 and electrode column 12 has a mutual capacitance (mutual capacitance) C _m ; and each electrode row 11 and each electrode column 12 has a self capacitance (self capacitance) C _s . The touch panel 100 of this embodiment can detect the stylus more efficiently and more accurately than the conventional touch panel to perform related functions. The stylus referred to in this embodiment may generally refer to a general non-specially manufactured or capacitive stylus.

Continuing to refer to FIG. 1, for the self-capacitance C _s , a voltage is applied to the electrode row 12 or electrode row 11 during the self-scan period, and then the same electrode row 12 or electrode row 11 is measured by a detection circuit (not shown). Line 11 is used to detect a stylus touching the front surface (or touch surface) of the touch panel 100 . For the mutual capacitance C _m , apply a voltage to one axis (such as the electrode row 12 ) during the mutual scan period, and then measure the other axis (such as the electrode row 11 ) through the detection circuit to detect the touch A stylus for the panel 100 .

FIG. 2 is a schematic diagram illustrating a sequence of scan (or measurement) frames. According to one of the features of this embodiment, self raw data (self raw data) of a plurality (ten as shown in FIG. 2 ) of previous scanning frames (related to the self-capacitance C _s ) can be accumulated. Since the intensity of the original data obtained by the stylus during detection is usually weak, the touch sensitivity can be enhanced after accumulating the original data of the scanned frames.

According to another feature of this embodiment, continue to refer to FIG. 2 , in each scan frame, execute multiple (two as shown in FIG. 2 ) identical self scan cycles (self scan cycle), and then use these self scan cycles The self-scanned raw data are aggregated. In this way, the aggregated raw data can enhance the touch sensitivity of the touch panel 100 .

According to another feature of this embodiment, continue referring to FIG. 2 , in addition to executing one or more self-scanning cycles, at least one mutual scan cycle (mutual scan cycle) is also executed in each scan frame, as shown in FIG. 2 . Mutual raw data (related to the mutual capacitance C _m ) of the executed mutual scanning period can be used to confirm that the stylus touches the surface of the touch panel 100 . For example, in this embodiment, the touch recognition will be confirmed only when both the self-scanning period and the inter-scanning 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 will not be confirmed. Simultaneous execution of the self-scanning period and the inter-scanning period can be used to prevent the impact of changes in the surrounding environment on the touch panel 100 .

In this embodiment, as shown in FIG. 3A , for the self-capacitance C _s , when the self-raw data (one or more self-scanning cycles) is greater than the preset self-touch threshold TH _s , the touch recognition is detected. . As shown in FIG. 3B , for the mutual capacitance C _m , when the mutual raw data (of at least one mutual scan period) is greater than the preset mutual touch threshold TH _m , the touch recognition is detected.

FIG. 4 shows a flowchart of recognizing a touch action of a stylus according to an embodiment of the present invention. In step 41 , the self-raw data corresponding to the self-capacitance C _s (in one or more self-scanning periods) is compared with the self-touch threshold TH _s . If the result of step 41 is negative (ie, the self-raw data is not greater than the self-touch threshold TH _s ), then ignore the touch action (step 42 ). Otherwise, the process goes to step 43, and the mutual original data corresponding to the mutual capacitance C _m (in the scanning frame) is compared with the mutual touch threshold TH _m . If the result of step 43 is negative (ie, the mutual raw data is not greater than the mutual touch threshold TH _m ), ignore the touch action (step 44 ); otherwise, in step 45 , increment the count value. If the count value is not greater than the set value ("No" branch path of step 46), the flow returns to step 41 to process the next scanning 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 FIG. 3A or FIG. 3B , the count value is used in conjunction with the set value to prevent false touch recognition caused by unstable raw data. In this embodiment, as shown in FIG. 4 , the touch action will be recognized only when the original data is stable (that is, the original data is greater than the touch threshold for 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, the preset number of times that the raw data is greater than the touch threshold is increased to enhance the accuracy of touch recognition. Furthermore, in the stylus mode, the algorithm is limited to single-touch recognition, rather than multi-touch recognition in the finger mode.

FIG. 5 shows a flow chart of releasing the touch action of the stylus (leaving the stylus mode) according to an embodiment of the present invention. In step 51 , compare the self-raw data corresponding to the self-capacitance C _s (in one or more self-scanning periods) with the self-touch threshold TH _s . If the self-raw data is not smaller than the self-touch threshold TH _s , ignore the self-raw data (step 52 ). Otherwise, the process goes to step 53, and the mutual original data corresponding to the mutual capacitance C _m (in the scan frame) is compared with the mutual touch threshold TH _m . If the mutual original data is not smaller than the mutual touch threshold TH _m , ignore the mutual original data (step 54 ); otherwise, in step 55 , count up the count value. If the count value is not greater than the set value ("No" branch path of step 56), the flow returns to step 51 to process the next scanning frame. If the count value is greater than the set value ("Yes" branch path of step 56), the touch action is canceled and the touch panel 100 leaves the stylus mode (step 57). As shown in FIG. 3A or FIG. 3B , the count value is used in conjunction with the set value to prevent false touch release caused by unstable raw data. In this embodiment, as shown in the process shown in FIG. 5 , only when the original data is stable (that is, the original data is smaller than the touch threshold for a preset number of times), the touch action will be actually released.

FIG. 6 shows a flow chart of releasing the touch action of the stylus (leaving the stylus mode) according to another embodiment of the present invention. In step 61 , the mutual raw data corresponding to the mutual capacitance C _m (in the scan period) is compared with the mutual threshold TH related to the finger touch of the finger mode. The aforementioned mutual threshold TH related to finger touch is usually greater than the mutual touch threshold TH _m related to touch of the stylus pen in the stylus mode. If the mutual raw data is not greater than the mutual threshold TH, then ignore the mutual raw data (step 62). Otherwise, if the mutual raw data is greater than the mutual threshold TH, it means that the finger touches the touch panel 100 , then the touch action of the stylus is released and the touch panel 100 leaves the stylus mode (step 63 ).

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the scope of the claims of the present invention; all equivalent changes or modifications that are completed without departing from the spirit disclosed by the invention shall be included in the present invention. within the scope of the claimed invention.

Claims (14)

1. A touch panel capable of detecting a stylus, comprising: a plurality of electrode rows arranged along the first axis; and A plurality of electrode rows are arranged along the second axis, each electrode row and each electrode row have a mutual capacitance at the intersection, and each electrode row and each electrode row has a self-capacitance; Wherein, a voltage is applied to the electrode column or electrode row in a self-scanning period, and then the same electrode column or electrode row is measured to detect the stylus touching the surface of the touch panel; in a mutual scanning period applying a voltage in one axis, and then measuring the other axis to detect the stylus touching the surface of the touch panel; Wherein in each scanning frame, at least one self-scanning period and at least one mutual scanning period are performed, and when the self-scanning period and the mutual scanning period are detected, the touch recognition of the stylus will be confirmed, Wherein self-raw data related to self-capacitance of a plurality of previous scanning frames are accumulated. 2 . The touch panel capable of detecting a stylus according to claim 1 , wherein in each scanning frame, a plurality of identical self-scanning cycles are performed, and then the self-scanning raw data of these self-scanning cycles are summed up. 3. The touch panel capable of detecting a stylus according to claim 2, wherein in a scanning frame, when the self-raw data is greater than a preset self-touch threshold, and the mutual original data is greater than a preset mutual-touch threshold, The touch recognition of the stylus will be confirmed. 4. The touch panel capable of detecting a stylus according to claim 2, wherein in a scan frame, when the self-raw data is less than a preset self-touch threshold, and the mutual original data is less than a preset mutual-touch threshold, The touch action of the stylus will be released. 5. The touch panel capable of detecting a stylus according to claim 1, wherein in a scan frame, when the mutual raw data is greater than a preset mutual threshold related to finger touch, the touch action of the stylus will be was lifted. 6. The touch panel capable of detecting a stylus according to claim 1 , wherein the touch recognition of the stylus will only be detected after the self-raw data related to the self-capacitance and the mutual raw data related to the mutual-capacitance are stable. confirm. 7. The touch panel capable of detecting a stylus according to claim 1, wherein the touch action of the stylus is not detected until the self-raw data related to the self-capacitance and the mutual raw data related to the mutual-capacitance are stable. lifted. 8. A method for detecting a stylus using a touch panel, comprising: providing a plurality of electrode rows arranged along the first axis; providing a plurality of electrode columns arranged along the second axis, each electrode row and each electrode column have a mutual capacitance at the intersection, and each electrode row and each electrode column have a self-capacitance; applying a voltage to the electrode row or electrode row in a self-scanning period, and then measuring the same electrode row or electrode row to detect a stylus touching the surface of the touch panel; Applying a voltage on one axis during a mutual scanning period, and then measuring the other axis to detect the stylus touching the surface of the touch panel; In each scanning frame, at least one self-scanning period and at least one mutual scanning period are performed, and when both the self-scanning period and the mutual scanning period are detected, the touch recognition of the stylus will be confirmed; and Self-raw data related to self-capacitance of a plurality of previous scan frames are accumulated. 9. The method of using a touch panel to detect a stylus according to claim 8, further comprising: In each scanning frame, perform a plurality of identical self-scanning periods; and sum up the self-scanning raw data of these self-scanning periods. 10. The method for detecting a stylus using a touch panel according to claim 9, wherein in a scan frame, when the self-raw data is greater than a preset self-touch threshold, and the mutual original data is greater than a preset mutual-touch threshold , the touch recognition of the stylus will be confirmed. 11. The method for detecting a stylus using a touch panel according to claim 9, wherein in a scanning frame, when the self-raw data is less than a preset self-touch threshold, and the mutual original data is less than a preset mutual-touch threshold , the touch action of the stylus will be released. 12. The method of using a touch panel to detect a stylus according to claim 8, wherein in a scanning frame, when the mutual raw data is greater than a preset mutual threshold related to finger touch, the touch action of the stylus will be released. 13. The method of using a touch panel to detect a stylus according to claim 8, wherein the touch recognition of the stylus starts after the self-raw data related to the self-capacitance and the mutual raw data related to the mutual-capacitance are stable. will be confirmed. 14. The method of using a touch panel to detect a stylus according to claim 8, wherein the touch action of the stylus starts after the self-raw data related to the self-capacitance and the mutual raw data related to the mutual-capacitance are stabilized. will be lifted.