Touch screen liquid crystal display
Disclosed herein are liquid-crystal display (LCD) touch screens that integrate the touch sensing elements with the display circuitry. The integration may take a variety of forms. Touch sensing elements can be completely implemented within the LCD stackup but outside the not between the color filter plate and the array plate. Alternatively, some touch sensing elements can be between the color filter and array plates with other touch sensing elements not between the plates. In another alternative, all touch sensing elements can be between the color filter and array plates. The latter alternative can include both conventional and in-plane-switching (IPS) LCDs. In some forms, one or more display structures can also have a touch sensing function. Techniques for manufacturing and operating such displays, as well as various devices embodying such displays are also disclosed.
1. A touch-sensitive surface, comprising:
a first substrate; and
a conductive black mask layer disposed below the first substrate;
wherein the conductive black mask layer is patterned into a plurality of separate touch sensing electrodes and configured to perform capacitive touch sensing.
2. The touch-sensitive surface of claim 1 , further comprising one or more charge amplifiers electrically coupled to at least some of the plurality of separate touch sensing electrodes.
3. The touch-sensitive surface of claim 1 , wherein the plurality of separate touch sensing electrodes are configured as self-capacitance electrodes.
4. The touch-sensitive surface of claim 1 , wherein the plurality of separate touch sensing electrodes are configured as touch drive electrodes.
5. The touch-sensitive surface of claim 4 , further comprising a conductive layer disposed above the first substrate and patterned into a plurality of separate touch sense electrodes.
6. The touch-sensitive surface of claim 1 , wherein the plurality of separate touch sensing electrodes are configured as touch sense electrodes.
7. The touch-sensitive surface of claim 6 , further comprising a conductive layer disposed below the conductive black mask layer and patterned into a plurality of separate touch drive electrodes.
8. The touch-sensitive surface of claim 1 , further comprising a plurality of connecting traces formed in the conductive black mask layer and electrically coupled to each of the plurality of separate touch sensing electrodes.
9. The touch-sensitive surface of claim 1 , further comprising a plurality of connecting traces routed below the patterned black mask layer to hide the plurality of connected traces.
10. The touch-sensitive surface of claim 1 , integrated with a plurality of display layers, the display layers comprising:
a liquid crystal layer; and
an active matrix layer.
11. The touch-sensitive surface of claim 10 , further comprising color filter material disposed between at least some of the plurality of separate touch sensing electrodes.
12. The touch-sensitive surface of claim 1 , wherein the conductive black mask is formed from CrO 2 .
13. The touch-sensitive surface of claim 1 , wherein the conductive black mask is formed as a conductive black matrix.
14. A method for reducing visual artifacts and performing touch detection in a touch-sensitive display, comprising:
hiding opaque stackup elements using a conductive black mask layer;
patterning a plurality of separate touch sensing electrodes in the conductive black mask layer; and
performing touch detection using the plurality of separate touch sensing electrodes in the conductive black mask layer.
15. The method of claim 14 , further comprising electrically coupling one or more charge amplifiers to at least some of the plurality of separate touch sensing electrodes to perform the touch detection.
16. The method of claim 14 , further comprising configuring the plurality of separate touch sensing electrodes as self-capacitance electrodes.
17. The method of claim 14 , further comprising configuring the plurality of separate touch sensing electrodes as touch drive electrodes.
18. The method of claim 14 , further comprising configuring the plurality of separate touch sensing electrodes as touch sense electrodes.
19. The method of claim 14 , further comprising forming a plurality of connecting traces in the conductive black mask layer and electrically coupling the plurality of connecting traces to each of the plurality of separate touch sensing electrodes.
20. The method of claim 14 , further comprising integrating the plurality of separate touch sensing electrodes into a plurality of display layers.