Fringing Field Effect in the Lumped-Capacitance Method for Permittivity Measurement

Theoretical analysis of the fringing field effect in the lumped-capacitance method for permittivity measurement for both shunt- and series-capacitor methods is given. It is shown that while the measured real part of the complex permittivity is larger than the true value by a factor depending on the ratio of the fringing to the parallel-plate capacitances, the imaginary part is not affected by the fringing field.