Editing Touchscreen (section)

==== Self-capacitance ====
Self-capacitance sensors can have the same layout as mutual capacitance sensors, but, with self-capacitance all the traces usually operate independently, with no interaction between different traces. Along with several other methods, the extra capacitive load of a finger on a trace electrode may be measured by a current meter, or by the change in frequency of an RC oscillator.

Traces are sensed, one after the other until all the traces have been sensed. A finger may be detected anywhere along the whole length of a trace (even "off-screen"), but there is no indication where the finger is along that trace. If, however, a finger is also detected along another intersecting trace, then it is assumed that the finger position is at the intersection of the two traces. This allows for the speedy and accurate detection of a single finger.

Although mutual capacitance is simpler for multi-touch, multi-touch can be achieved using self-capacitance.

Self-capacitive touch screen layers are used on mobile phones such as the [[Sony Xperia Sola]],<ref name="SonyDev">{{Cite web |url=http://developer.sonymobile.com/wp/2012/03/13/imagine-controlling-your-phone-without-touching-the-screen-floating-touch-makes-it-possible-video/ |title=Self-capacitive touch described on official Sony Developers blog |access-date=2012-03-14 |archive-date=2012-03-14 |archive-url=https://archive.today/20120314110416/http://developer.sonymobile.com/wp/2012/03/13/imagine-controlling-your-phone-without-touching-the-screen-floating-touch-makes-it-possible-video/ |url-status=live }}</ref> the [[Samsung Galaxy S4]], [[Galaxy Note 3]], [[Galaxy S5]], and [[Galaxy Alpha]].

Self-capacitance is far more sensitive than mutual capacitance and is mainly used for single touch, simple gesturing and proximity sensing where the finger does not even have to touch the glass surface. Mutual capacitance is mainly used for multitouch applications.<ref>{{cite journal|title=Comparison of self capacitance and mutual capacitance. |doi=10.1017/S1743921315010388 |arxiv=1612.08227 |last1=Du |first1=Li |year=2016 |s2cid=220453196 }}</ref> Many touchscreen manufacturers use both self and mutual capacitance technologies in the same product, thereby combining their individual benefits.<ref>{{cite web|url=http://www.cypress.com/products/cypress-sensing-technologies|title=Hybrid self and mutual capacitance touch sensing controllers }}</ref>