Sensing device having photo sensing element alternately operated in different biased states and related touch-controlled display device

Abstract

The present invention provides a sensing device and a display device utilizing the sensing device. A photo sensing element of the sensing device is alternatively operated in a biased state and a reverse-biased state to prevent the stress issue. Furthermore, the sensing device improves the S/N ratio by generating an output signal through an active component. The display device including the sensing device prevents the stress issue and improves the S/N ratio by using specific driving signals.

What is claimed is: 
     
         1 . A sensing device, comprising:
 a photo sensing element, having a first terminal and a control terminal, wherein the control terminal is configured to receive a first signal, and the first terminal of the photo sensing element is electrically connected to a second signal through at least one other element;   wherein the first signal and the second signal are both driving signals each supporting two logic levels, and a logic level transition of the first signal is not synchronized with a logic level transition of the second signal.   
     
     
         2 . The sensing device of  claim 1 , wherein the photo sensing element is a photo diode or a silicon rich oxide (SRO) element. 
     
     
         3 . The sensing device of  claim 1 , wherein the at least one other element is a first capacitor having a first electrode electrically connected to the first terminal of the photo sensing element and a second electrode electrically connected to the second signal, and the first terminal of the photo sensing element receives the second signal through the first capacitor; and the sensing device further comprises a first transistor electrically connected to the first terminal of the photo sensing element and having a first terminal, a control terminal and a second terminal. 
     
     
         4 . The sensing device of  claim 3 , wherein when the first signal has a high logic level, the first transistor is not conductive. 
     
     
         5 . The sensing device of  claim 3 , wherein the first transistor is electrically connected to the first terminal of the photo sensing element through the control terminal of the first transistor, and the control terminal of the first transistor is electrically connected to the first electrode of the first capacitor. 
     
     
         6 . The sensing device of  claim 3 , further comprising:
 a second capacitor, having a first electrode electrically connected to the first electrode of the first capacitor and a second electrode.   
     
     
         7 . The sensing device of  claim 3 , further comprising:
 a second transistor, having a first terminal electrically connected to a second terminal of the first transistor, a control terminal for receiving a control signal and a second terminal electrically connected to a data read line, wherein the control signal is utilized for controlling a conductive state of the second transistor.   
     
     
         8 . A touch-controlled display device, comprising:
 a plurality of scan lines for receiving scan line driving signals;   a plurality of data lines;   a plurality of sensing devices of  claim 3  arranged in a matrix, each of the plurality of sensing devices being coupled to at least one of the plurality of scan lines; and   a plurality of pixel elements arranged in a matrix, each of the plurality of pixel elements being coupled to one of the plurality of scan lines and to one of the plurality of data lines, respectively.   
     
     
         9 . The touch-controlled display device of  claim 8 , wherein each of the sensing devices further comprises:
 a second capacitor, having a first electrode electrically connected to the first electrode of the first capacitor and a second electrode;   wherein the first signal and the second signal are different scan line driving signals of the scan line driving signals, and an activation timing of the second signal is prior to an activation timing of the first signal.   
     
     
         10 . A sensing device, comprising:
 a photo sensing element, having a first terminal and a control terminal for receiving a first signal, wherein the first signal is a driving signal that supports two logic levels;   a first capacitor, having a first electrode electrically connected to the first terminal of the photo sensing element and a second electrode; and   a first transistor electrically connected to the first terminal of the photo sensing element and having a first terminal, a control terminal and a second terminal.   
     
     
         11 . The sensing device of  claim 10 , wherein the first transistor is electrically connected to the first terminal of the photo sensing element through the first terminal of the first transistor, and the first terminal of the first transistor is electrically connected to the first electrode of the first capacitor. 
     
     
         12 . A touch-controlled display device, comprising:
 a plurality of scan lines for receiving scan line driving signals;   a plurality of data lines;   a plurality of sensing devices of  claim 10  arranged in a matrix, each of the plurality of sensing devices being coupled to at least one of the plurality of scan lines; and   a plurality of pixel elements arranged in a matrix, each of the plurality of pixel elements being coupled to one of the plurality of scan lines and to one of the plurality of data lines, respectively.