Capacitive touchscreens are designed to react to the capacitance of a human body. To my understanding the touchscreen is measuring local distortions of the electric field.

Is there a way to influence the electric field of the touchscreen from a greater distance such as a centimeter above the screen?

What I am thinking is that creating an electrostatic charge might perhaps help, for example similar to the way an ionizer works. Unfortunately I lack the electrical knowledge to understand the implications of 'the other half of the capacitor' which is needed to excite the touchscreen.

The goal is to create a 'hover stylus' similar to the wacom digitizer (which of course works differently based on electromagnetic resonance). The stylus does not need to be practical yet, just trying to understand whether any device would excite the touchscreen from a small distance, it could contain a battery, Tesla coil, anyone?

  • \$\begingroup\$ it may be possible to use a resonant syulus, but you'd need first to determine the apropriate frequency \$\endgroup\$ May 11, 2019 at 3:43
  • 1
    \$\begingroup\$ @ElliotAlderson that question is helpful but it does not discuss the aspect of having a small gap between the touchscreen and the stylus \$\endgroup\$
    – fan711
    May 11, 2019 at 17:53


Browse other questions tagged or ask your own question.