Sagnac fiber optic interferometer for measuring rotational speed with wavelength stabilised light source

摘要

The subject-matter of the invention is the additional use of an integrated optical chip (MIOC) as a Michelson interferometer for stabilising the wavelength of a light source (L) within a fibre-optic Sagnac interferometer for rotation rate measurement, in which a phase modulator contained in the integrated optical chip is acted on both via a digital phase ramp (AT1) dependent on the rotation rate for resetting, and by a statically independent second signal component which optimises the working point of the phase modulator (PM). With this kind of statically independent alteration of the phase modulation, the measurement signal of the Michelson interferometer, dependent on the light wavelength, can be demodulated from the detector read-out signal and can be used for readjusting the light-source wavelength by means of light-source temperature alteration and/or injection-current alteration for the light source (L). In open-loop operation, changes in the scale factor can be compensated for from the measurement signal dependent on the light wavelength. IMAGE