Patent ID: 8537143

Claim:
A touch-controlled system, comprising: a screen, arranged for displaying an image with hidden coding; a host, coupled to the screen, arranged for driving the screen to display the image; and an electric pen, wherein when the electronic pen touches the screen, the electronic pen captures a part of the image on the screen and sends the captured image to the host, wherein at least one hidden information is hidden in the image captured by the electronic pen, the host is arranged for analysing and decoding the hidden information of the captured image to obtain a cursor position where the electronic pen touches, so as to display the cursor position on the screen, wherein before the host drives the screen, a least significant bit (LSB) of each pixel of the image to be displayed is hidden into the hidden information; and the host analyses the LSB of each pixel of the captured image to obtain the hidden information, and performs decoding to obtain coordinates of the cursor position.