High-sensitivity Kerr-effect technique for determination of 2-dimensional electric fields

On the basis of the Kerr electrooptic effect, a highly sensitive measurement method, which could be used for measuring two-dimensional electric field distributions in liquid dielectrics, is proposed. By applying a pulse voltage to an optical phase modulator, the authors changed the incident light from a linearly polarized light into two elliptically polarized components. Modulating both states of polarization of these two components as well as the DC electric field with an AC electric field, they determined the amplitudes and directions of both the AC and DC electric field intensity in liquids with small Kerr constants (~10^-15 m/V²). The proposed method is automatic and has a sensitivity ≈100 V/cm. The two-dimensional electric field distributions in tricresyl phosphate liquid dielectric are measured with this method