ELECTRIC FIELD SENSOR AND ADJUSTMENT METHOD THEREOF

摘要

An electric field sensor includes: a light source (1); an electro optic crystal (7) to which electric field based on a signal to be measured is applied and whose double refractive index changes according to the electric field, thereby changing the polarization state of the light coming from the light source and emitting the light; and detection sections (9, 17, 19, 21) for detecting an electric signal in accordance with the polarization state of the light emitted from the electro optic crystal (7). There are also provided an opposing electrode (12) to make a pair together with a signal electrode (11) for applying the electric field based on the signal to be measured to the electro optic crystal (7) and an auxiliary electrode (61) which is electrically connected to the opposing electrode (12) and forms capacity between the auxiliary electrode and the ground.