Ring laser gyroscope

About: Ring laser gyroscope is a research topic. Over the lifetime, 2070 publications have been published within this topic receiving 18609 citations. The topic is also known as: Sagnac interferometer.

Readout beamsplitting/combining apparatus for ring laser gyro

Abstract: A readout apparatus for both partial beams (101,102) of a ring laser gyro (100) is designed strictly symmetrical so that each partial beam until its detection on a photodetector (114-117) travels the same path length. Both partial beams are differently polarized (105,106), are superimposed (107,108,109) and then again geometrically split-up (110,111) whereby a fixed phase relationship (90°) may be introduced between the split-up partial beams (FIG. 1).

Correlation relationship between the dissipative and conservative backscattering components in the ring resonator of a laser gyroscope

Abstract: We report the results of measuring the complex coupling coefficients in ring He – Ne lasers with a radiation wavelength of 632.8 nm. It is found that in assembling ring resonators from mirrors of the same quality, there is no correlation between the dissipative and conservative backscattering components. The analysis of the measurement results shows that this behaviour is associated with the speckle structure of the backscattered field in the ring resonator. The presence of backscattering (BS) sources with a random phase on the mirrors’ surface leads to a spread in the values of the BS parameters, which is described by the Rayleigh distribution function. Ways to reduce the spread in the values of dissipative and conservative backscattering components in assembling the ring resonators are discussed.

Observation by Means of An Underground Ring Laser Gyroscope of Love Waves Generated in the Mediterranean Sea: Source Direction and Comparison with Models

Abstract: In fall 2018, we have observed, by means of an underground ring laser gyroscope, the microseismic (MS) activity induced by the Mediterranean Sea in the 2–5 s period range. In the amplitude spectra, a clear peak highly correlated with a collocated seismometer appears during a large storm activity ranging from 24 November to 1 December 2018. The peak of the spectra, both for rotation rate and acceleration, are located at 3.3 s. The peak amplitudes are of 8×10−10 rad/s−1 and 3×10−6 ms−2, respectively, for vertical rotation rate and horizontal acceleration. We perform the source direction estimation by maximizing the correlation of the vertical rotation rate with the transverse acceleration. The local estimation of the direction of the wavefield is then compared with the sea state hindcasts that provide a modeling of the possible MS noise sources.

Experimental demonstration of mode-matching and Sagnac effect in a millimeter-scale wedged resonator gyroscope

Abstract: The highly efficient coupling of light from conventional optical components to optical mode volumes lies in the heart of chip-based micro-devices, which is determined by the mode-matching between propagation constants of fiber taper and the whispering-gallery-mode (WGM) of the resonator. Optical gyroscopes, typically realized as fiber-optic gyroscopes and ring-laser gyroscopes, have been the mainstay in diverse applications such as positioning and inertial sensing. Here, the mode-matching is theoretically analyzed and experimentally verified. We observe the Sagnac effect in a millimeter-scale wedged resonator gyroscope, which has attracted considerable attention and has been rapidly promoted in recent years. We demonstrate a bidirectional pump and probe scheme, which directly measures the frequency beat caused by the Sagnac effect. We establish the linear response between the detected beat frequency and the rotation velocity. The clockwise and counterclockwise rotation can also be distinguished according to the value of the frequency beat. The experimental results verify the feasibility of developing the gyroscope in a WGM resonator system and pave the way for future development.