Patent ID: 7903255

Claim:
An optical device for a physical parameter's registration and measurement comprising: an optical cavity being a closed waveguide loop having at least a first nested configuration with at least a first axis of symmetry, the cavity having at least a first waveguides crossing section within the cavity, said waveguides crossing section preserving the symmetry of the cavity; a clockwise (CW) and a counterclockwise (CCW) optical waves being introduced to the cavity using at least a first coupler; the CW and the CCW optical waves being extracted from the cavity using at least a second coupler; the first and the second couplers positioned symmetrically relative to the first axis of symmetry thus creating equal optical paths for CW and CCW; a detector registering the difference between the extracted CW and CCW waves characteristics; and a signal processing unit calculating the physical parameter of interest based on the registered difference.