Reducing the dimensions of optical gyroscopes is a crucial task and resonant fiber optic gyroscopes are promising candidates for its solution. The paper presents a prototype of a miniature resonant interferometric gyroscope of a strategic accuracy class. Due to the use of passive optical elements in this gyroscope, it has a great potential for miniaturization, alongside a low production cost and ease of implementation, since it does not require many feedback loops. The presented prototype shows results on a zero instability of 20°/h and an angle random walk of 0.16°/√h. A theoretical model explaining the nature of the multipath interference of resonant spectra and establishing the relationship between the resonator parameters and the output parameters of the presented prototype is proposed. The results predicted are in agreement with the experimental data. The prototype gyroscope demonstrates a scale factor instability and a change in the average signal level, which is due to the presence of polarization non-reciprocity, occurring due to the induced birefringence in the single-mode fiber of the contour. This problem requires further investigation to be performed.

Simple measures to improve the signal-to-noise ratio of optical frequency domain reflectometer (OFDR) readings are described. After applying a two-stage optical amplification of the backscattered signal, as well as eliminating the source of spurious reflections, it was possible to increase the signal-to-noise ratio of the frequency domain trace from 8 to 19 dB. This technique can be applied in fiber optic sensors and metrology of fiber optic and integrated optical elements.

Today, the task of developing microoptical gyroscopes is topical. Usually, tunable lasers with a built-in frequency stabilization system are used in such gyroscopes. They are comparatively bulky, which hinders the real miniaturization of optical gyroscopes. We propose a new approach implemented by using a Mach–Zehnder modulator with a passive ring resonator connected to one of its arms. This makes it possible to obtain a mutual configuration and makes the use of a tunable laser optional. Two ring resonators made of the polarization-maintaining fiber, suitable for use as sensitive elements of a gyroscope, were realized and investigated. Their Q-factor is equal to 14.5 × 10⁶ and 28.9 × 10⁶. The maximum sensitivity of the proposed method when using the described resonators is 3.2 and 1.8 °/h, respectively. The first experimental setup of a resonator gyroscope implementing this approach has been manufactured and analyzed. When measuring the rotation speed by the quasi-harmonic signal span and its phase, the measurement accuracy was approximately 11 and 0.4 °/s, respectively.

When radiation propagates in an optical ring resonator, apart from the main peaks, additional peaks are observed. It is known that the strain of optical fiber induces birefringence. Assuming that an additional peak is associated with the main peak, we proposed a model describing the relative position of the main and additional resonance peaks. The model predicts induced birefringence based on the frequency difference between the main and additional peaks. For experimental verification, we fabricated an optical ring resonator, measured the difference between the main and additional peaks and obtained the birefringence value. This value was –(3.42 ± 0.51)·10⁻⁷, consistent with values obtained in other studies.

Subject of study. Using a ring resonator as an example, this paper describes the general operating principle for optical resonators, the characteristics of such resonators, and the relationship between resonator quality factor Q and gyroscope sensitivity. Several sensor devices (optical resonators) were compared for use in the development of a miniature resonant optical gyroscope. These optical resonators were of three different types: a fiber-optic resonator, a whispering gallery mode resonator, and an integrated optical resonator ring. Methodology. The fiber-optic resonator consists of two fiber-optic splitters spliced together, the whispering gallery mode resonator consists of a three-dimensional dielectric structure in which whispering gallery modes are excited, and the integrated optical resonator ring consists of an optical waveguide and closed loop mounted on a common substrate. The characteristics of the high-Q(Q=10⁶−10⁹) whispering gallery mode resonators and fiber-optic resonators were measured using a narrow-band scanning laser and an oscillograph. A simpler approach, with a broadband laser source and an optical spectrum analyzer, was used for the low-Q(Q<10⁶) integrated optical resonators. Main results. Values of Q=5.2×10⁸, Q=4.3×10⁶, and Q=1.1×10⁴ were obtained for a MgF₂ disk resonator, fiber-optic disk resonator, and integrated optical resonator, respectively. Practical significance. The whispering gallery mode resonator turns out to be the most promising of these sensor devices since it has the highest Q and the highest accuracy for angular velocity measurements. Fiber optic resonators are competitive but are more sensitive to temperature and external mechanical effects. Integrated optical resonators have the advantage of miniaturization and the ability to include temperature stabilization components and components that provide resistance to mechanical effects.

Polarization maintaining fibers (PMF) are used in various fields of photonics and telecommunications, so the study of the propagation of optical radiation