| 摘要 |
<p>An optical voltage.electric field sensor of the type which includes a light source (31), a polarizer (32) for linearly polarizing an incident light beam emanated from the light source, a phase plate (33) for applying a phase difference to the linearly polarized light beam, a Pockels element (34) for modulating the linearly polarized light beam applied with the phase differenc in accordance with a voltage or electric filed applied thereto, an analyzer (35) for separating the modulated light beam into a S-polarized light beam and a P-polarized light beam, a first light-receiving element (37a) arranged to receive the S-polarized light beam for converting the S-polarized light beam into a first electric signal V1 indicative of the intensity of the light beam, and a second light-receiving element (37b) arranged to receive the P-polarized light beam for converting the P-polarized light beam into a second electric signal V2 indicative of the intensity of the light beam. The sensor further includes a first calculation circuit (38a) for calculating an equation V11 = (V1 - DC1)/DC1 (where DC1 is a direct current component of the first electric signal) to produce an output V11 therefrom, a second calculation circuit (38b) for calculating an equation V22 = (V2 - DC2)/DC2 (where DC2 is a direct current component of the second electric signal) to produce an output V22 therefrom, and a third calculation circuit (38c) for calculating an equation V3 = 1/[( alpha /V11) - ( beta /V22)] (where alpha and beta are constants) to produce an output V3 for measurement of the applied voltage or electric field.</p> |
