  Touch sensing, as a major human/machine interface, is widely used in various
commercial products such as smart watches, mobile phones, tablets and TVs.
State-of-the-art touch detections are mainly based on mutual capacitive
sensing, which requires necessary contact-touch, limiting the mobile user
experience. Recently, remote gesture sensing is widely reported in both academy
and industry as it can provide additional user-experience for mobile interface.
The capacitive remote gesture sensing is mainly based on detecting
self-capacitance, achieving high resolution through eliminating the parasitic
mutual capacitance. In this work, we overview the different generations of
touchscreen technology, comparing the touch and remote gesture sensing
technologies difference. In addition, different remote gesture sensing
technologies are also compared. The limitations and potentials of different
topologies are discussed and a final conclusion about the technology trends is
summarized in the end.
