This relates to touch sensing circuitry integrated into the display pixel stackup (i.e., the stacked material layers forming the display pixels) of a display, such as an LCD display. Circuit elements in the display pixel stackups can be grouped together to form touch sensing circuitry that senses a touch on or near the display. Touch sensing circuitry can include, for example, touch signal lines, such as drive lines and sense lines, grounding regions, and other circuitry. An integrated touch screen can include multi-function circuit elements that can form part of the display circuitry designed to operate as circuitry of the display system to generate an image on the display, and can also form part of the touch sensing circuitry 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 of an LCD 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. In this way, for example, in some embodiments a display with integrated touch sensing capability may be manufactured using fewer parts and/or processing steps, and the display itself may be thinner, brighter, and require less power.
The last part is crucial. Apple is working toward taking the simple and elegant external industrial designs inside. Fewer parts lead to lower cost manufacturing in the long run. Less processing steps lead to improved throughput and higher yields. And the user will have a better experience with an iPhone thanks to a thinner, brighter display that requires less power.