A Fabry-Perot interference sensor based on solid-core photonic crystal fiber and its manufacturing method

Abstract

The invention provides a Fabry-Perot interferometric sensor based on a photonic crystal fiber and a manufacturing method thereof. The sensor is composed of a conventional communication single-mode fiber and a solid photonic crystal fiber, wherein the conventional communication single-mode fiber and the solid photonic crystal fiber are welded by using a certain welding method. Because air holes ona cladding of the photonic crystal fiber collapse, an air cavity (namely, an F-P cavity) is formed between the two fibers, and the two end faces (namely, the front and rear surfaces of the air cavity) of the photonic crystal fiber and the single-mode fiber are two reflecting surfaces of the F-P cavity. The solid photonic crystal fiber is made of a single material, and does not cause the mismatching of thermal expansion coefficients of materials in the process of temperature variation, thereby ensuring that the influence of temperature variation on the interferometric sensor is small; in the manufacturing process, only a fiber cutting and welding process is used, therefore, the preparation process is simple; by using the sensor, high-fineness and high-contrast interference fringes can be obtained, therefore, the sensor has a great application potential in large-capacity and quasi-distributed sensing systems; and the sensor is in an all-fiber structure, and has the advantages of small volume, good robustness and low cost.

Description

technical field [0001] The invention belongs to the technical field of optical fiber sensing, and in particular relates to an extrinsic optical fiber Fabry-Perot interference sensor based on a solid-core photonic crystal optical fiber and a manufacturing method thereof. Background technique [0002] Optical fiber Fabry-Perot (F-P) interference sensor, with its advantages of strong anti-electromagnetic interference, high precision, good stability, good reliability, and high resolution, can be used in the measurement of strain, pressure, vibration, acceleration, temperature, and refractive index. and other fields have been widely used. The extrinsic fiber-optic F-P interferometer is the most widely used fiber-optic F-P interferometer. Its interference cavity is composed of air or other non-fiber solid media (such as hollow quartz glass tubes), and the optical fiber only plays the role of light transmission. The role of the medium. It not only has all the advantages of fiber ...

AI Technical Summary

Problems solved by technology

However, due to the higher diffraction loss in the spherical cavity, the F-P interference fringes are close to the two-beam interference fringes, the fringe contrast is only 8-12dB, and the fineness is only 5

Therefore, the measurement signal of the sensor made by this kind of interferometer is weak, and the measurement accuracy is low when using wavelength demodulation, which is not suitable for large-capacity, quasi-distributed sensing system

Images