Integrated touch screen
Displays with touch sensing circuitry integrated into the display pixel stackup are provided. Circuit elements, such as touch signal lines, such as drive lines and sense lines, grounding regions, in the display pixel stackups can be grouped together to form touch sensing circuitry that senses a touch on or near the display. An integrated touch screen can include multi-function circuit elements that can operate as circuitry of the display system to generate an image on the display, and can also form part of a touch sensing system that senses one or more touches on or near the display. The multi-function circuit elements can be, for example, capacitors in display pixels that can be configured to operate as storage capacitors/electrodes, common electrodes, conductive wires/pathways, etc., of the display circuitry in the display system, and that may also be configured to operate as circuit elements of the touch sensing circuitry.
1. A stackup of a plurality of display pixels, the stackup comprising:
a first layer of conductive material including gate lines;
a second layer of conductive material including data lines;
a third layer of conductive material including first conductive lines in a first direction, each of the first conductive lines including a plurality of first line portions extending through plural display pixels and separated from each other in the first direction by disconnections in the third layer; and
second conductive lines in a second direction transverse to the first direction, each of the second conductive lines including a plurality of second line portions extending through plural display pixels and separated from each other in the second direction by disconnections,
a first, second and third region each having circuit elements of the display pixels, the third region disposed between the first and second regions, and
wherein circuit elements of the display pixels in the first region are electrically connected together in the first direction by a first plurality of the first line portions, and the circuit elements of the display pixels in the first region are electrically connected together in the second direction by a first plurality of the second line portions; and
wherein at least one conductive pathway connects circuit elements of the first region to circuit elements of the second region wherein the at least one conductive pathway runs through one or more display pixels of the third region without electrically connecting to the circuit elements of the third region.
2. The stackup of claim 1 , wherein the third layer includes the second conductive lines and wherein the second line portion disconnections are in the third layer.
3. The stackup of claim 2 , wherein the circuit elements of the display pixels of the second region are electrically connected together in the first and second directions by a second plurality of the first line portions and a second plurality of the second line portions, respectively, and are disconnected in the third layer from the circuit elements in the first region.
4. The stackup of claim 3 , wherein the circuit elements are common electrodes of the display pixels.
5. The stackup of claim 3 , wherein the circuit elements of the display pixels of the third region are electrically connected together in the first and second directions by a third plurality of the first line portions and a third plurality of the second line portions, respectively, and are disconnected in the third layer from the circuit elements in the first and second regions.
6. The stackup of claim 5 , wherein the at least one conductive pathway includes:
a common line in the first layer;
a first conductive contact electrically connecting at least some of the circuit elements of the first region to the common line; and
a second conductive contact electrically connecting at least some of the circuit elements of the second region to the common line.
7. The stackup of claim 5 , further comprising:
a fourth region of the display pixels located between the first region and the second region, wherein the at least one conductive pathway runs through one or more display pixels of the fourth region without electrically connecting to the circuit elements of the fourth region.
8. The stackup of claim 7 , further comprising:
a conductive line connecting the fourth region to a ground.
9. A touch sensing system comprising the stackup of claim 5 , further comprising:
a drive signal generator connected to one of the first and second regions; and
a sense channel connected to the third region.
10. The touch sensing system of claim 9 wherein each display pixel has a common electrode and wherein:
the first plurality of first line portions and the first plurality of second line portions connect together the common electrodes of the display pixels in the first region,
the second plurality of first line portions and the second plurality of second line portions connect together the common electrodes of the display pixels in the second region,
the third plurality of first line portions and the third plurality of second line portions connect together the common electrodes of the display pixels in the third region, and
wherein the drive signal generator is connected to at least one of the first plurality of first line portions or the first plurality of second line portions in the first region or to at least one of the second plurality of first line portions or the second plurality of second line portions in the second region.
11. The touch sensing system of claim 10 wherein the sense channel is connected to one of the third plurality of first line portions or the third plurality of second line portions, and the sense channel includes a charge amplifier.
12. A touch screen comprising:
display circuitry including first circuit elements of display pixels and connections to a display driver; and
touch sensing circuitry including
first conductive lines including some of the first circuit elements of the display pixels, and
second conductive lines that include at least two conductive line portions electrically connected together by at least one conductive pathway that includes second, different circuit elements of the display pixels,
wherein one of the first and second conductive lines are drive lines of the touch sensing circuitry, and the other of the first and second conductive lines are sense lines of the touch sensing circuitry.
13. The touch screen of claim 12 , wherein the at least two conductive line portions include at least some of the first circuit elements.
14. The touch screen of claim 12 , wherein the first circuit elements include common electrodes of the display pixels.
15. The touch screen of claim 12 , wherein the second circuit elements include common voltage lines.
16. The touch screen of claim 12 , wherein the touch sensing circuitry further includes:
a conductive region substantially between two conductive lines of the first and second conductive lines, wherein the conductive region is grounded.
17. The touch screen of claim 16 , wherein the conductive region is grounded to an alternating current (AC) ground.
18. A computer system comprising:
a processor;
a memory;
a display system including
display circuitry that includes a plurality of circuit elements of display pixels, and
a display controller; and
a touch sensing system including
touch sensing circuitry that includes the plurality of circuit elements grouped into a plurality of first regions and a plurality of second regions, wherein electrically conductive pathways through the second regions connect circuit elements of a plurality of first regions while bypassing circuit elements of the second regions,
the circuit elements of each of the first regions being electrically connected together along a first direction and along a second direction, transverse to the first direction, and
a touch controller.
19. The computer system as recited in claim 18 wherein the circuit elements of each of the second regions are electrically connected together along at least one of the first and second directions.
20. The computer system as recited in claim 19 wherein the circuit elements of each of the second regions are electrically connected together along both the first direction and the second direction.