Fiber-optic gyroscope based on single-mode single polarized photon crystal optical fiber

Abstract

The invention discloses a fiber-optic gyroscope based on a single-mode single polarized photon crystal optical fiber. A broadband optical fiber light source emits polarized light; the polarized light enters a polarization-maintaining optical fiber coupler via a polarization-maintaining optical fiber; the polarized light is divided into two beams, wherein one beam enters a hollow head to be attenuated, and the other beam enters an optical phase modulator via a polarization-maintaining optical fiber; the light is divided into two beams by the optical phase modulator; the two beams of light are respectively output to two ends of a optical fiber sensitive ring via a single-mode single-polarization photonic crystal tail fiber in the optical phase modulator; the optical fiber sensitive ring is wound by a single-mode single-polarization photonic crystal optical fiber; the two beams of light are respectively spread clockwise and anticlockwise in the optical fiber sensitive ring; output light is returned back to the optical phase modulator to generate interference; interference light enters the polarization-maintaining optical fiber coupler to obtain an interference signal; and an optical detector detects the interference signal to obtain the rotation speed of the measurement system. According to the fiber-optic gyroscope disclosed by the invention, the polarization error of the fiber-optic gyroscope can be effectively reduced, the null shift of the fiber-optic gyroscope is reduced, and the mechanical performance and the temperature performance of the fiber-optic gyroscope are improved.

Description

technical field [0001] The invention relates to a fiber optic gyroscope based on a single-mode single-polarization photonic crystal fiber, belonging to the technical field of fiber optic gyroscopes. Background technique [0002] The fiber optic gyroscope is a high-precision sensor for measuring the rotational angular velocity of an object. Its principle is based on the Sagnac effect: when the gyroscope rotates, a rotation angle is generated between the two beams of light waves propagating clockwise and counterclockwise in the fiber optic coil. The rate Ω is proportional to the phase difference φ s , ideally, by measuring the phase difference φ s And real-time signal processing can accurately obtain the rotational angular velocity of the object. Fiber optic gyroscope is a new type of all-solid-state inertial device with simple structure, low cost and high potential precision. It will become the main instrument in the field of inertial navigation and strategic applications. ...

AI Technical Summary

Problems solved by technology

However, for systems that require high polarization stability, polarization-maintaining fibers still cannot meet the requirements

Especially under the action of temperature, the introduction of the stress region of the traditional polarization-maintaining fiber is the basis for obtaining high birefringence, but when the temperature rises, the stress in the stress region is gradually released, and the birefringence value gradually decreases or even disappears, resulting in the traditional polarization-maintaining fiber. Poor temperature stability of fiber polarization characteristics

Therefore, within the entire operating temperature range of the fiber optic gyroscope, changes in the birefringence of the traditional polarization-maintaining fiber will cause changes in the polarization-maintaining ability of the transmitted light, polarization coupling, and crosstalk, which will cause a large bias error in the fiber optic gyroscope and affect its accuracy.

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