Abstract: It is provided a touch screen device applied in an electronic information technology area. In the touch screen device supporting an active capacitance stylus, a demodulation unit demodulates a signal received by a reception unit by two orthogonal signals, and then an amplitude recovery unit recovers an amplitude of the signal received by the reception unit, the amplitude of the signal received by the reception unit can be recovered relatively exactly without the need that the demodulation signal must be synchronous with the signal received by the reception unit (or the signal transmitted from the active capacitance stylus), and there is no need to add additional hardware resources for synchronization in the touch screen device of the embodiment of the present invention compared with the existing detection method which needs to perform synchronization of the demodulation signal and the signal transmitted from the active capacitance stylus in the prior art.

Abstract: The embodiments of the present invention disclose a touch stylus, a touch detection method and a touch detection system, which are suitable to be used for writing on a capacitive touch screen and can increase the success rate of touch. A method according to an embodiment of the present invention includes: receiving, by a sensing electrode, a square wave signal sent from a stylus tip of a touch stylus; performing a detection process on the square wave signal, by a sensing detection unit, the sensing detection unit having a clock synchronized with a clock of the touch stylus; determining, by a signal processing unit, whether a touch event occurs according to the square wave signal processed with the detection process; and calculating position coordinates of the touch event and reporting the position coordinates to a system control unit, by the signal processing unit, if a touch event occurs.