An optical gyroscope and a method for measuring an angular velocity of rotation are described. A closed-path optical cavity is configured for receiving at least a first optical signal circulating as at least one cavity mode of pre-determined orientation (inside the optical cavity. An extractor in optical communication with the optical cavity is configured for extracting a fraction of at least the circulating first optical signal from the optical cavity, wherein an amplitude of the extracted fraction increases when a resonance condition for the optical cavity in optical communication with the extractor is approached. A readout channel included in the optical gyroscope comprises an interferometric device adapted to spectrally modify the extracted fraction so as to produce a spectral Vernier effect. A difference between free spectral ranges of the interferometric device and the optical cavity is larger than the associated spectral widths. Readout detectors are included in the readout channel for detecting optical power levels of the spectrally modified optical signal, based on which the angular velocity is determined.

Systems and methods for embodiments having an extra thick ultraviolet durability coating are described herein. For example, a system may include a laser block assembly. The system may also include a cavity in the laser block assembly. Further, the system may include a plurality of multilayer mirrors in the cavity. In certain embodiments, at least one multilayer mirror of the plurality of multilayer mirrors may include a plurality of alternating layers of a first optical material having a high index of refraction and a second optical material having a first low index of refraction. Additionally, the at least one multilayer mirror may include a multilayer durability coating disposed on the plurality of alternating layers.

An optical gyroscope and a method for measuring an angular velocity of rotation are described. A closed-path optical cavity is configured for receiving at least a first optical signal circulating as at least one cavity mode of pre-determined orientation (inside the optical cavity. An extractor in optical communication with the optical cavity is configured for extracting a fraction of at least the circulating first optical signal from the optical cavity, wherein an amplitude of the extracted fraction increases when a resonance condition for the optical cavity in optical communication with the extractor is approached. A readout channel included in the optical gyroscope comprises an interferometric device adapted to spectrally modify the extracted fraction so as to produce a spectral Vernier effect. A difference between free spectral ranges of the interferometric device and the optical cavity is larger than the associated spectral widths. Readout detectors are included in the readout channel for detecting optical power levels of the spectrally modified optical signal, based on which the angular velocity is determined.

A device includes an optical resonator having four ports including a first port, a second port, a third port, and a fourth port. A first electronic circuit is configured to calculate a first information representative of a power difference between optical signals supplied by two of the four ports. A method of operating a device is also disclosed.

An apparatus and a method for detecting rotation based on the Sagnac effect is disclosed. Input light having sufficient power is injected into a circulating optical resonator to thereby excite an optomechanical oscillation of the resonator at an instantaneous mechanical angular frequency. Rotation of the circulating optical resonator causes a change in a frequency of the optomechanical oscillation of the resonator, which in turn causes the instantaneous mechanical angular frequency to change. The optomechanical oscillation produces modulation sidebands in the resonating optical field at the instantaneous mechanical angular frequency and harmonics thereof, which are demodulated from the optical frequency by detection in a photodetector. Differences in the instantaneous mechanical angular frequency induced by rotation are detected by processing the photodetector output signal.

Apparatus, systems, and methods associated with enhancement of phase response of intracavity phase interferometers are applicable in a variety of applications.

A photonic device for detecting rotation and a corresponding method for operation thereof are disclosed. The photonic device includes a readout structure coupled to a ring resonator at one or more coupling points. Light is split between a lower waveguide and an upper waveguide of the readout structure in a forward direction at a beam splitter. The light in the waveguides traveling in the forward direction is coupled into the ring resonator and subsequently back into the waveguides in a reverse direction. The light is spatially phase tilted and is combined at the beam splitter. The combined light is detected by a split detector.

In one embodiment, a method is provided. The method comprises transmitting a first laser pump signal to an optical resonator; adjusting a frequency of the first laser pump signal; generating a first order Stokes signal from the first laser pump signal in an optical resonator; measuring a first beat signal frequency; ceasing transmission of the first laser pump signal to the optical resonator; transmitting a second laser pump signal to the optical resonator; adjusting a frequency of the second laser pump signal; generating a first order Stokes signal from the second laser pump signal in the optical resonator; and measuring a second beat signal frequency; ceasing transmission of the second laser pump signal to the optical resonator.

In one embodiment, a method is provided. The method comprises transmitting a first laser pump signal to an optical resonator; adjusting a frequency of the first laser pump signal; generating a first order Stokes signal from the first laser pump signal in an optical resonator; measuring a first beat signal frequency; ceasing transmission of the first laser pump signal to the optical resonator; transmitting a second laser pump signal to the optical resonator; adjusting a frequency of the second laser pump signal; generating a first order Stokes signal from the second laser pump signal in the optical resonator; and measuring a second beat signal frequency; ceasing transmission of the second laser pump signal to the optical resonator.

A method of making a readout mirror for a ring laser gyroscope comprises forming an optical substrate component that includes a lower surface, a first upper surface portion substantially parallel to the lower surface, and a second upper surface portion angled with respect to the lower surface; performing a coarse polish of the second upper surface portion; forming an optical part having a first surface; performing a super polish of the first surface of the optical part; applying a first beam splitter layer to the super polished first surface of the optical part, to produce a beam splitter side of the optical part; and bonding the beam splitter side of the optical part, using an optical adhesive, to the coarse polished second upper surface portion of the substrate component, to produce a reflector member. The reflector member is configured to reduce external cavity light scattering in the ring laser gyroscope.