Voltage sensing systems and methods for passive compensation of temperature related intrinsic phase shift
US6307666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 2000 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | Jan 13, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/0322
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized. A reflecting prism redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization representing the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.