Optically-excited fiber grating cantilever beam harmonic oscillator vacuum degree sensor

Abstract

The invention relates to an optically-excited fiber grating cantilever beam harmonic oscillator vacuum degree sensor, and belongs to the technical field of fiber sensors. The optically-excited fiber grating cantilever beam harmonic oscillator vacuum degree sensor comprises an LD light source, a directional fiber coupler, a photoelectric detector, a sensing probe, coupling liquid, a micro-machined fiber grating, a metal plated film, and a coupling filtering FBG. The quality factors of the fiber grating cantilever beam harmonic oscillator sensor are influenced by air damping so as to influence the resonance amplitude of a fiber grating cantilever beam and finally change the wavelength of the reflection signal center of the FBG cantilever beam harmonic oscillator sensor, and thus the vacuum degree can be measured. The optically-excited fiber grating cantilever beam harmonic oscillator vacuum degree sensor has the advantages of simple structure and strong anti-electromagnetic interference performance, and can satisfy the requirement of micro, real-time on-line distributed and multi-point monitoring.

Description

technical field [0001] The invention belongs to the technical field of optical fiber sensors, in particular to a fiber Bragg grating (FBG: Fiber Bragg Grating) cantilever resonator sensor for measuring vacuum. Background technique [0002] Vacuum degree measurement is an important part of vacuum technology. It is one of the key applications of current vacuum degree measurement technology for vacuum degree detection in harsh and narrow spaces (such as toxic, flammable, explosive, high temperature and high pressure, etc.). The satisfactory technology choice is silicon micro-mechanical probe method. The vacuum sensor made of silicon micro-mechanical probe has the advantages of miniaturization, easy integration, high sensitivity and low cost. However, the silicon micromechanical probe detection method also has disadvantages: (1) The excitation methods of silicon micromechanical sensors include piezoelectric excitation, electrostatic excitation, or electrothermal excitation, etc....

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Problems solved by technology

However, the silicon micromechanical probe detection method also has disadvantages: (1) The excitation methods of silicon micromechanical sensors include piezoelectric excitation, electrostatic excitation, or electrothermal excitation, etc., all of which need to make additional excitation elements on the silicon micro-cantilever beam, and the excitation efficiency is low. ; (2) The silicon micromechanical probe method requires electrical signal excitation and output, and has poor anti-electromagnetic interference ability, which is not easy to realize distributed multi-point monitoring. (3) The integrated packaging of silicon micromechanical sensors is difficult

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