31.2: Eliminating Ghost Touches on a Self‐Capacitive Touch‐Screen

Abstract

When two or more touches are detected on a self-capacitive touch-screen, positional ambiguities known as "ghost" touches are created. A novel method of distinguishing between real and "ghost" touches is described. Experimental results for dual-touch give an SNR of over 55 dB, appropriate for secured touch detection in severe environments such as avionics.

45.3: High Intensity Radiated Field Effect on Projected Capacitive Touchscreen

“…In a previous paper [5], we provided a method for removing the ghosting effect on self capacitive screens. The measurement method uses a synchronous demodulation for sensing the voltage variation resulting from the capacitive change induced by a touch (Figure 2).…”

Skinflow: A soft robotic skin based on fluidic transmission

“…This way the constant c in Equation 1 can be reduced and this would cause the increase of resolution in the direction of depth. In the case of the ghost touch problem, traditional solutions that were effective for previous touchscreens [23] cannot be used (e.g. voltage sensing) simply because the transduction mechanism is different.…”

Electromagnetic field analysis of capacitive touch panels

“…On the other hand, PCT panels based on the selfcapacitive sensing method are used only as capacitive sensors for applications such as capacitive switches, proximity sensing, and touch pads for notebook PCs [19]. This is because the self-capacitive sensing method has a problem called "ghost effect", which is the inability to correctly detect the multi-input [20]. PCT panels with self-capacitive sensing have not been used so far as input devices for mobile devices, but the method is now being considered as a candidate for 3D gesture input interfaces because of its high sensitivity [21].…”