Touch screen system

Abstract

A touch screen system includes an in-cell type optical touch device for displaying images and receiving a light signal, an out-cell type touch device for sensing a finger or a non-optical stylus, a first functional unit connected with the in-cell type optical touch device, a second functional unit connected with the out-cell type touch panel and a third functional unit connected with the first functional unit and the second functional unit. The out-cell type touch device is disposed on the in-cell type optical touch device. The first functional unit converts an analog sensing signal received by the in-cell type optical touch device into a first electrical signal. An object-sensing signal generated from the out-cell type touch panel is processed by the second functional unit to generate a second electrical signal. The third functional unit analyzes the first electrical signal and the second electrical signal and generates valid output signals.

What is claimed is: 
     
         1 . A touch screen system, comprising:
 a display device having a plurality of pixel electrodes disposed in a display area;   a plurality of optical sensors disposed in a matrix of pixel electrodes, which are activated by an optical signal and driven by a signal line of the pixel electrode to convert the optical signal into a raw current signal;   a processor capable of determining a light spot location based on the activated optical sensor and generating a first electrical signal based on the raw current signal;   an object-sensing device capable of responsive to a touch implement on the display area and generating a second electrical signal with a set of position coordinates of the touch implement; and   a controller for comparing the first electrical signal and the second electrical signal to determine whether the first electrical signal or the second electrical signal as an output signal.   
     
     
         2 . The touch screen system according to  claim 1 , wherein the controller generates a set of position coordinates associated with the first electrical signal prior to the second electrical signal when the first and the second electrical signal are received simultaneously. 
     
     
         3 . The touch screen system according to  claim 1 , further comprising a light pen having two terminals, one of the terminals is used for radiating light to activate optical sensors, and the other one of the terminals is used for input sensed by the object-sensing detector. 
     
     
         4 . The touch screen system according to  claim 3 , wherein the optical signal is generated from a light pen when exerting against the display device. 
     
     
         5 . The touch screen system according to  claim 1 , wherein the first electrical signal is determined by comparing a current difference between the light spot location on the display area and the other location of the display area. 
     
     
         6 . The touch screen system according to  claim 1 , wherein the optical sensors and the pixel electrodes are fabricated by the same fabrication process.