Piezoelectric and optical setup to measure an electrical field: Application to the longitudinal near-field generated by a tapered coax

We propose a new setup to measure an electrical field in one direction. This setup is made of a piezoelectric sintered lead zinconate titanate film and an optical interferometric probe. We used this setup to investigate how the shape of the extremity of a coaxial cable influences the longitudinal electrical near-field generated by it. For this application, we designed our setup to have a spatial resolution of 100 um in the direction of the electrical field. Simulations and experiments are presented.