Principle of Operation
The open-loop ‘minimum configuration’ architecture is employed.
The broadband light-emitting diode (SLD module) couples the light into an input/output fiber coupler (II).
Then the light passes through a polarizer and a spatial filter which ensure the reciprocity of the counter-propagating light beams through the fiber coil.
Another coupler (I) splits the two light beams in the fiber optic coil where they pass through a harmonic modulator (PZT).
After passing through the fiber coil, the two light beams recombine and pass back through the polarizer and are directed onto the photodetector. Synchronous demodulation behind the detector converts the rotationally-induced first harmonic signal into a rate proportional voltage.