Display apparatus and touch sensing method thereof

A display apparatus having a touch sensing function, comprising:

• an active matrix substrate including a plurality of pixel electrodes, a plurality of column electrodes for transmitting display data signals and for driving and sensing touch signals during a period to perform touch detection, and a plurality of row electrodes crossing the column electrodes for transmitting display scan signals, wherein each of the column electrodes acts as a driving column electrode and a sensing column electrode respectively through a switch switching between an electrical connection to a driving module and a sensing module,
• wherein said at least one of the column electrodes as the driving column electrode is connected to the driving module, and simultaneously said another column electrode as the sensing column electrode is connected to the sensing module,
• wherein during one row electrode scanning period:
• at least one of the plurality of row electrodes transmits a scan driving signal for touch detection,
• the driving module transmits a touch driving signal through the driving column electrode, wherein during transmitting the touch driving signal through the driving column electrode, at least an external object couples the touch driving signal from the driving column electrode to the sensing column electrode so as to form a coupling signal on the sensing column electrode, and at the same time, from the sensing column electrode, the sensing module senses the coupling signal which is caused by the touch driving signal coupled from the driving column electrode through the external object and formed on the sensing column electrode;,
• wherein one-dimensional coordinate results for the external object along the row electrodes are obtained according to the coupling signal sensed by the sensing module during each row electrode scanning period, and, according to the one-dimensional coordinate results from each row electrode scanning period, two-dimensional coordinates of the external object are formed by combining the one-dimensional coordinate results for the external object along the row electrodes.