Polar-coordinate-based data analysis scheme for high-voltage measurement system using the Pockels electro-optic effect

Abstract

A voltage measurement system based on the Pockels electro-optic effect typically has, due to a half-wave voltage Vπ of a Pockels cell, a limitation on the unambiguous measurable range. To overcome such a limitation, we develop a polar-coordinate-based data analysis scheme with a simultaneous measurement of cos(π V/Vπ) and sin(π V/Vπ), where V is the voltage the Pockels cell experiences, i.e., the voltage we wish to measure. The developed data analysis scheme also corrects, without knowledge of Vπ, a misalignment of the Pockels cell and an imbalanced transmittance of a beam splitter between the horizontal and vertical components of the polarized laser beam. Thus, increased accuracy of not only the Vπ measurement during calibration procedure but also the voltage measurement itself is also achieved.