Variation of Sensitivity of Solid Dielectric Capacitance Transducers
J.W.R. Griffiths, Narayan P. Murarka · The Journal of the Acoustical Society of America · 1964
A capacitance transducer, using a thin metalized plastic film as a solid dielectric, can be subject to a loss of sensitivity owing to a reduction in the effective polarizing voltage caused by charge building up on the inner surface of the plastic. However, by a periodic reversal of the polarizing voltage, it is possible to prevent this accumulation of charge and, in consequence, the sensitivity of the device remains constant.