Electro-optic voltage sensor for sensing voltage in an E-field

• Main Authors: Davidson, James R, Crawford, Thomas M, Seifert, Gary D
• Format: Patent
• Language: English
• Published: 26.03.2002

1. Field of the Invention The present invention relates generally to an electro-optic high voltage sensor for sensing and/or measuring an E-field produced by an energized conductor. More particularly, it concerns an electro-optic voltage sensor which utilized the Pockels electro-optic effect to measure voltage. A miniature electro-optic voltage sensor and system capable of accurate operation at high voltages has a sensor body disposed in an E-field. The body receives a source beam of electromagnetic radiation. A polarization beam displacer separates the source light beam into two beams with orthogonal linear polarizations. A wave plate rotates the linear polarization to rotated polarization. A transducer utilizes Pockels electro-optic effect and induces a differential phase shift on the major and minor axes of the rotated polarization in response to the E-field. A prism redirects the beam back through the transducer, wave plate, and polarization beam displacer. The prism also converts the rotated polarization to circular or elliptical polarization. The wave plate rotates the major and minor axes of the circular or elliptical polarization to linear polarization. The polarization beam displacer separates the beam into two beams of orthogonal linear polarization representing the major and minor axes. The system may have a transmitter for producing the beam of electro-magnetic radiation; a detector for converting the two beams into electrical signals; and a signal processor for determining the voltage.