Capacitive touch screen

Abstract

The present invention provides a mutual capacitive multi-touch screen. The conductive strip pattern allows that, when a touch range of each external conductive object on the mutual capacitive multi-touch screen is larger than a predetermined condition, capacitive coupling between each external conductive object and first conductive strip is greater than capacitive coupling between each external conductive object and second conductive strip, such that the proportion of a driving signal flowing out of the first conductive strip via at least one first external conductive object in the external conductive objects and into the second conductive strip via at least one second external conductive object in the external conductive objects decreases as the number of second external conductive objects increases.

What is claimed is: 
     
         1 . A touch processor, executing the operation:
 determining whether at least one touch by at least one proximity object is valid according to the mutual capacitive coupling signals between a plurality of driving electrodes and a plurality of sensing electrodes, wherein the touch processor determines that the touch valid because the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes.   
     
     
         2 . The touch processor according to  claim 1 , wherein the touch processor determines that the touch is invalid because the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is smaller than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes, wherein the proximity object is a pen. 
     
     
         3 . The touch processor according to  claim 1 , wherein the area of the plurality of driving electrodes covered directly by the proximity object is greater than the area of the plurality of sensing electrodes covered directly by the proximity object such that the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes. 
     
     
         4 . The touch processor according to  claim 3 , wherein the areas of the intersections of the plurality of driving electrodes and the plurality of sensing electrodes are excluded from the area of the plurality of driving electrodes covered directly by the proximity object. 
     
     
         5 . The touch processor according to  claim 1 , wherein the plurality of driving electrodes are distributed over a first layer, and the plurality of sensing electrodes are distributed over a second layer, wherein the plurality of driving electrodes are paralleled with a first axis, and the plurality of sensing electrodes are paralleled with a second axis, wherein the plurality of driving electrodes and the plurality of sensing electrodes are bare for each other, and the first axis and the second axis are orthogonal. 
     
     
         6 . The touch processor according to  claim 5 , wherein the first layer is placed between the proximity object and the second layer such that the distance between the proximity object and the first layer is smaller than the distance between the proximity object and the second layer, and the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes. 
     
     
         7 . The touch processor according to  claim 5 , wherein the second layer is placed between the first layer and a display, wherein a plurality of signal values of the plurality of sensing electrodes comprises the mutual capacitive coupling signals and noises from the display when the display updates frames during mutual capacitive coupling detection, and a plurality of differential signal values or a plurality of dual differential signal values generated from the plurality of signal values suppress the noises. 
     
     
         8 . The touch processor according to  claim 1 , wherein the plurality of driving electrodes and the plurality of sensing electrodes are distributed over the same layer. 
     
     
         9 . The touch processor according to  claim 1 , further executing the operation:
 determining the position of the valid touch according to a plurality of signal values, a plurality of differential signal values or a plurality of dual differential signal values generated from the mutual capacitive coupling signals.   
     
     
         10 . The touch processor according to  claim 9 , wherein when detecting the plurality of differential signal values, the plurality of sensing electrodes comprises:
 a first sensing electrode with a first signal value; and   a second sensing electrode with a second signal value, wherein a differential signal value is the difference between the first signal value and the second signal value.   
     
     
         11 . The touch processor according to  claim 9 , wherein when detecting the dual plurality of differential signal values, the plurality of sensing electrodes comprises:
 a first sensing electrode with a first signal value;   a second sensing electrode with a second signal value; and   a third sensing electrode with a third signal value, wherein a dual differential signal value is the difference between the first differential signal value and the second differential signal value, wherein the first differential signal value is the difference between the first signal value and the second signal value, and the second differential signal value is the difference between the second signal value and the third signal value.   
     
     
         12 . A touch method, comprising:
 determining whether at least one touch by at least one proximity object is valid according to the mutual capacitive coupling signals between a plurality of driving electrodes and a plurality of sensing electrodes, wherein it is determined that the touch valid because the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes.   
     
     
         13 . The touch processor according to  claim 12 , wherein it is determined that the touch is invalid because the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is smaller than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes, wherein the proximity object is a pen. 
     
     
         14 . The touch processor according to  claim 12 , wherein the area of the plurality of driving electrodes covered directly by the proximity object is greater than the area of the plurality of sensing electrodes covered directly by the proximity object such that the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes. 
     
     
         15 . The touch processor according to  claim 14 , wherein the areas of the intersections of the plurality of driving electrodes and the plurality of sensing electrodes are excluded from the area of the plurality of driving electrodes covered directly by the proximity object. 
     
     
         16 . The touch processor according to  claim 12 , wherein the plurality of driving electrodes are distributed over a first layer, and the plurality of sensing electrodes are distributed over a second layer, wherein the plurality of driving electrodes are paralleled with a first axis, and the plurality of sensing electrodes are paralleled with a second axis, wherein the plurality of driving electrodes and the plurality of sensing electrodes are bare for each other, and the first axis and the second axis are orthogonal. 
     
     
         17 . The touch processor according to  claim 16 , wherein the first layer is placed between the proximity object and the second layer such that the distance between the proximity object and the first layer is smaller than the distance between the proximity object and the second layer, and the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes. 
     
     
         18 . The touch processor according to  claim 16 , wherein the second layer is placed between the first layer and a display, wherein a plurality of signal values of the plurality of sensing electrodes comprises the mutual capacitive coupling signals and noises from the display when the display updates frames during mutual capacitive coupling detection, and a plurality of differential signal values or a plurality of dual differential signal values generated from the plurality of signal values suppress the noises. 
     
     
         19 . The touch processor according to  claim 16 , wherein the plurality of driving electrodes and the plurality of sensing electrodes are distributed over the same layer. 
     
     
         20 . The touch processor according to  claim 12 , further comprising:
 determining the position of the valid touch according to a plurality of signal values, a plurality of differential signal values or a plurality of dual differential signal values generated from the mutual capacitive coupling signals.   
     
     
         21 . The touch processor according to  claim 20 , wherein when detecting the plurality of differential signal values, the plurality of sensing electrodes comprises:
 a first sensing electrode with a first signal value; and   a second sensing electrode with a second signal value, wherein a differential signal value is the difference between the first signal value and the second signal value.   
     
     
         22 . The touch processor according to  claim 20 , wherein when detecting the dual plurality of differential signal values, the plurality of sensing electrodes comprises:
 a first sensing electrode with a first signal value;   a second sensing electrode with a second signal value; and   a third sensing electrode with a third signal value, wherein a dual differential signal value is the difference between the first differential signal value and the second differential signal value, wherein the first differential signal value is the difference between the first signal value and the second signal value, and the second differential signal value is the difference between the second signal value and the third signal value.   
     
     
         23 . A touch device, comprising
 a plurality of driving electrodes, receiving a driving signal;   a plurality of sensing electrodes, mutual capacitively coupling with the plurality of driving electrodes; and   a touch processor, determining whether at least one touch by at least one proximity object is valid according to the mutual capacitive coupling signals between the plurality of driving electrodes and the plurality of sensing electrodes, wherein the touch processor determines that the touch valid because the mutual capacitive coupling signal between the proximity object and the plurality of driving electrodes is greater than the mutual capacitive coupling signal between the proximity object and the plurality of sensing electrodes.