Optical fiber vibration sensor with temperature self-compensation function

Abstract

An optical fiber vibration sensor with a temperature self-compensation function comprises a first single-polarization optical fiber, and the output end of the first single-polarization optical fiber is connected with the input end of a first high-birefringence photonic crystal optical fiber through a first welding point. The output end of the first high-birefringence photonic crystal fiber is connected with the input end of a second high-birefringence photonic crystal fiber through a second welding point, and the output end of the second high-birefringence photonic crystal fiber is connected with the input end of a second single-polarization fiber through a third welding point. An optical fiber on-line micro cantilever beam with a micro hanging weight is prepared in the middle of the second high-birefringence photonic crystal fiber, and a rigid capillary tube is arranged outside the optical fiber on-line micro cantilever beam; the optical axis of the single-polarization optical fiber and the optical axis of the high-birefringence photonic crystal optical fiber form an angle of 45 degrees, and the optical axes of the two high-birefringence photonic crystal optical fibers are orthogonal; according to the invention, the flat frequency response characteristic is provided for vibration signals with the frequency in the frequency band range of 5Hz-5kHz, and the antenna has the advantages of simple structure, low manufacturing cost and easy industrialization.

Description

technical field [0001] The invention relates to the technical field of optical fiber vibration sensors, in particular to an optical fiber vibration sensor with temperature self-compensation function. Background technique [0002] Vibration sensor is a detection device that captures environmental vibration information, and is widely used in various fields such as production and life, equipment status monitoring, and intelligent manufacturing. The existing electrical vibration sensor has poor anti-electromagnetic interference capability, narrow measurement frequency band, low sensitivity, requires power supply, and cannot meet the vibration measurement requirements in harsh environments such as substations in harsh electromagnetic environments, underground coal mines rich in gas, and oil wells. Compared with traditional electrical sensors, optical fiber vibration sensors have the advantages of strong electromagnetic interference resistance, high sensitivity and passive nature....

AI Technical Summary

Problems solved by technology

Due to the influence of the resonant frequency and mechanical stability of the cantilever beam itself, the measurement frequency band of this type of sensor is limited, and there are problems of temperature cross-sensitivity; in addition, the existing optical fiber vibration sensors usually require complex demodulation of phase, wavelength, light intensity, etc. The device is used to complete the extraction of the sensor signal, which leads to the complexity and high cost of the whole vibration measurement system

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