Display device including touch sensor
A display device include a first surface, a sensing capacitor having a sensing input electrode and a sensing output electrode, wherein the sensing capacitor stores a first amount of charges and the sensing capacitor stored a second amount of charges when an external object contacts on the first surface, a sensing input signal line electrically connected with the sensing input electrode and receiving a sensing input signal to charge the sensing capacitor to the first amount of charges, a sensing output signal line electrically connected with the sensing output electrode, and a sensing signal processor connected with the sensing output signal line, wherein the sensing signal processor determines whether an external objects contact on the first surface based on a voltage difference between the first amount of charges and the second amount of charges stored in the sensing capacitor.
1. A display device, comprising:
a substrate having a first surface and a second surface;
a sensing capacitor having a first sensing electrode and a second sensing electrode as two terminals of the sensing capacitor, wherein the first sensing electrode and the second sensing electrode are disposed on the second surface;
a first sensing signal line electrically connected with the first sensing electrode;
a second sensing signal line electrically connected with the second sensing electrode;
an insulating layer positioned on the first sensing electrode and the second sensing electrode, wherein the first sensing signal line is positioned on one side of the insulating layer and the second sensing signal line are positioned on the other side of the insulating layer;
a sensing signal processor connected with the first and second sensing signal lines;
a gate line transmitting a gate signal to a pixel, the gate line being positioned on the insulating layer, being adjacent to and substantially parallel to the first sensing signal line,
wherein the sensing signal processor determines whether an external object contacts on the first surface based on a voltage difference of the sensing capacitor,
wherein one of the first and second sensing signal lines transmits a sensing input signal to charge the sensing capacitor, and the other one of the first and second sensing signal lines transmits a sensing output signal from the sensing capacitor, and
wherein the first sensing signal line directly contacts the first sensing electrode everywhere the first sensing signal line overlaps the first sensing electrode, and
wherein at least of the first sensing electrode and the second sensing electrode includes a thinner portion, and only the thinner portion overlaps the gate line in a display area.
2. The display device of claim 1 , wherein the first sensing signal line has a lower resistance than the first sensing electrode, and the second sensing signal line has a lower resistance than the second sensing electrode.
3. The display device of claim 1 ,
wherein the second sensing signal line is connected to the second sensing electrode through a contact hole formed in the insulation layer.
4. The display device of claim 3 wherein the pixel emits light through the first surface.
5. The display device of claim 1 ,
wherein the second sensing signal line contacts and is electrically connected to the thinner portion.
6. The display device of claim 1 , wherein the first sensing signal line comprises a plurality of sub signal lines overlapping the first sensing electrode, and wherein the sub signal lines are substantially parallel to each other.
7. The display device of claim 4 ,
wherein at least one of the first sensing electrode and the second sensing electrode includes a plurality of sensing electrodes arranged in a column direction and a connection part connecting adjacent sensing electrodes, wherein the connection part has a smaller width than the sensing electrode.
8. The display device of claim 4 ,
wherein at least one of the first sensing electrode and the second sensing electrode includes a metal, and has a mesh shape having an opening for transmitting light emitting from the pixel.
9. The display device of claim 8 , further comprising:
a light blocking layer covering the first sensing electrode and the second sensing electrode.
10. The display device of claim 9 , further comprising:
an anti-reflective layer positioned on at least one of the first sensing signal line, the second sensing signal line, the first sensing electrode and the second sensing electrode.
11. The display device of claim 10 ,
wherein the anti-reflective layer includes at least one of CuNx, TiOx and SiNx.
12. The display device of claim 11 , further comprising:
a printed circuit board connected with a display panel having the pixel, the sensing capacitor, the first sensing signal line and the second sensing signal line through a printed circuit film,
wherein the printed circuit film has a flat, rigid film, and contacts a third surface of the display panel and a fourth surface of the printed circuit board, the third surface and the fourth surface facing a same direction.
13. The display device of claim 1 ,
wherein the sensing signal processor includes a current integrator configured to measure a voltage based on the first amount of charges and the second amount of charges stored in the sensing capacitor.