Patent · US Active

Optical sensor

US9983236B2 · kind B2 · utility

1Cited by

4References

17Claims

0Family size

Assignee

ABB Schweiz AG · CH

Inventors

Klaus Bohnert · Oberrohrdorf, CH
Andreas Frank · Sindelfingen, DE
Georg Muller · Neuss, DE
Lin Yang · Redwood City, US

Key dates

Filing date	Jun 20, 2016
Grant date	May 29, 2018
Priority date	—
Expiry date	Jun 20, 2036

Classification

Technology area (CPC G)Physics
CPC primaryG01R15/247
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

A method of increasing accuracy of optical sensors based on generating two sets of light waves having different velocities in the presence of a non-vanishing measurand field within a sensing element of the sensor is described. A defined static bias phase shift is introduced between the two sets of light waves. The sensor converts a total optical phase shift including static bias optical phase shifts and measurand-induced optical phase shifts into anti-phase optical power changes in at least two detector channels. The method includes steps of normalizing the optical power changes after their conversion into electrical detector signals in the two detector channels to reduce effects of uneven intensity or power of the light source and different loss or gain in the detector channels. Further methods, sensors and apparatus for temperature stabilizing such optical sensors and novel sensors are also presented.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.