Patent · US Expired

Method and apparatus for increasing the stability of a fiber optic gyroscope by controlling the phase and amplitude of the source modulating current

US5953122A · kind A · utility

4Cited by

3References

2Claims

0Family size

Assignee

LITEF GmbH · DE

Inventors

Wolfgang Ecke · Jena, DE
Eberhard Handrich · Kirchzarten, DE
Klaus Hilpert · Mannheim, DE
Michael Newkirch · Trier, DE

Key dates

Filing date	Jul 31, 1997
Grant date	Sep 14, 1999
Priority date	—
Expiry date	Jul 31, 2017

Classification

Technology area (CPC G)Physics
CPC primaryG01C19/721
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

A small modulation current is applied to the light source of a Sagnac-type fiber optic gyroscope to increase accuracy and/or stability of scale factor (open loop configuration) and to reduce bias errors and random walk (closed-loop configuration). The phase and amplitude of the modulation current are controlled through a control circuit whose reference is picked off at a first beamsplitter in series with the light source. In such a way, light emitted from the light source into the interferometer contains no modulation. The elimination of modulation removes a source that would otherwise cause deterioration of gyroscope stability resulting from light returning from the interferometer or due to electrical interference, thus limiting measurement accuracy.

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