Fiber-optic sensor and method

US10859607B2 · kind B2 · utility

Assignee

• ABB Power Grids Switzerland AG · CH

Inventors

• Georg Muller · Neuss, DE
• Klaus Bohnert · Oberrohrdorf, CH
• Andreas Frank · Sindelfingen, DE
• Philippe Gabus · Nyon, CH

Key dates

• Filing date: Feb 14, 2019
• Grant date: Dec 8, 2020
• Expiry date: Feb 14, 2039

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R19/32
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A fiber optic sensor and related method are described, with the sensor including a cross-coupling element in the optical path between a polarizing element and a sensing element, but separated from the sensing element itself; with the cross-coupling element generating a defined cross-coupling between the two orthogonal polarization states of the fundamental mode of a polarization maintaining fiber guiding light from the light source to the sensing element thus introducing a wavelength-dependent or temperature-dependent sensor signal shift to balance wavelength-dependent or temperature-dependent signal shifts due to other elements of the sensor, particularly signal shifts due to the wavelength dependence of the Faraday effect or the electro-optic effect constant.