The measurement of dielectric constants, with a note on preliminary work on the location of adsorption bands

Abstract

A survey is made of methods which have been devised to determine dielectric constants, using alternating currents ranging from audio to kilo-megacycle frequencies. Bridge methods are described which involve the comparison of capacities in various forms of Wheatstone network. Many determinations have been made which depend on the detection of current or voltage resonance, and on the frequency dependance of oscillators on capacity in their circuits. Borne free wave methods are described, which lead on to transmission line and co-axial line methods. For wavelengths smaller than 10cm wave guides and resonators are most suitable. As brief description is given of a new method for detecting absorption regions in liquids.