US 12,372,558 B2 · Device and method for measuring voltage by using optical element

Abstract

A voltage measuring device for measuring a voltage by using a Pockels cell includes a Pockels cell changing a refractive index of incident light based on an applied electric field, at least one non-polarized beam splitter splitting an incident beam, a first polarizing plate polarizing a first beam split by the at least one non-polarized beam splitter, a first light detector detecting light polarized based on the first polarizing plate, a ¼ wave plate elliptically polarizing and outputting a second beam split by the at least one non-polarized beam splitter, a second polarizing plate polarizing the elliptically polarized second beam, a second light detector detecting light polarized based on the ¼ wave plate and the second polarizing plate, and a controller configured to measure a voltage based on a first light intensity determined by the first light detector and a second light intensity determined by the second light detector.

Claims17

Dependent claims

A voltage measuring device comprising:

a Pockels cell whose birefringence varies based on an electric field applied to the Pockels cell, wherein the birefringence generates a phase difference;
at least one non-polarized beam splitter splitting an incident beam passing through the Pockels cell into a first beam and a second beam;
a first polarizing plate polarizing the first beam to output a polarized first beam;
a first light detector detecting the polarized first beam;
a ¼ wave plate elliptically polarizing the second beam to output an elliptically polarized second beam;
a second polarizing plate polarizing the elliptically polarized second beam to output a polarized second beam;
a second light detector detecting the polarized second beam;
and
a controller configured to measure a voltage corresponding to the electric field applied to the Pockels cell, based on a first light intensity determined by the first light detector and a second light intensity determined by the second light detector.

6 more elements

A method of measuring a voltage applied to a Pockels cell based on an intensity of light passing through the Pockels cell whose birefringence varies depending on the voltage, the birefringence generating a phase difference, the method comprising:

determining a first equation indicating a relationship between a first light intensity and the phase difference and a second equation indicating a relationship between a second light intensity and the phase difference;
and
measuring the voltage based on the first equation and the second equation,
wherein the first light intensity indicates an intensity of light which has passed through the Pockels cell and has been polarized based on a first polarizing plate, and detected by a first light detector, and
the second light intensity indicates an intensity of light which has passed through the Pockels cell and has been polarized based on a second polarizing plate and a ¼ wave plate, and detected by a second light detector.

2 more elements

Dependencies are inferred from the claim text.

Device and method for measuring voltage by using optical element

Life of this patent

Device and method for measuring voltage by using optical element

Life of this patent

Abstract

Claims17