Fig. 3: Finite-Element-Analysis (FEA) based electromagnetic simulations for optimal receiver electrode configuration.
From: Touchscreen communication (ToSCom): Electro-Quasistatic body communication during touch sensing
A For optimal signal reception, 4 configurations of receiver electrodes are analyzed. The ToSCom receiver is connected across electrodes 1 and 2. B Electric field plot for a surface infinitesimally above the system ground plate, showing electric field around the sharp edges of the ground plates have high field strength. C Channel loss across the entire touchscreen surface is analyzed with the finger moving across the leading diagonal. D Channel loss response for the 4 configurations of the ToSCom receiver. E Using 2 small electrodes to further optimize the channel loss. F Optimal, constant channel loss response with 2 small electrode configuration is shown. G Touch selectivity of ToSCom due to its Electro-Quasistatic (EQS) behavior is illustrated. Moving the finger away from the touchscreen shows a sharp increase in channel loss 1cm away from the screen.
