Fringing electric field sensor

Fig. 9.6.1 Cross sectional view of a fringing electric field sensor (see text for details). Different connection schemes can be used to vary the penetration depth of the sensor.

A. V. Mamishev, Design principles for multi-channel fringing electric field sensors, IEEE Sens. J., Apr. 2006, 6(2), 434-440. 

Dielectric spectroscopy techniques are promising for numerous applications that require non-invasive, non-destructive, non-contact, and real-time measurements. Non-invasive measurements with gas, liquid, solid, and mixed samples are possible on distance scales from nanometers to meters and a frequency of excitation from microhertz to terahertz. The main advantages of fringing electric field dielectric sensors include one-side access to material under test, convenience of application... 

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