Coupled type monomode fiber fadeout wave sensor

Abstract

The present invention is one coupled high-sensitivity single-mode fiber evanescent wave sensor, and belongs to the field of optical fiber and sensor technology. The sensor consists of mainly light source, optical fiber, fiber evanescent wave sensor element, detector, signal processing unit and container holding measured medium. It features the single-mode fiber; the melting cone type single-mode fiber coupler probe as the fiber evanescent wave sensor element; the basal body with the packed melting cone type single-mode fiber coupler probe, sensing single-mode fiber cone area, single-mode fiber lead-in ends and fixing glue to fix the fiber; the hollow channel for tested gas or liquid to be led in; and the container holding measured medium. The present invention has simple structure, high sensitivity, high selectivity of lowest measurement limit in ppb to ppm level, and other advantages

Description

Technical field: [0001] The invention relates to a novel coupled single-mode optical fiber evanescent wave sensor, which belongs to the technical field of optical fibers and sensors. Background technique: [0002] Optical fiber evanescent wave sensing technology is to change the intensity, phase or frequency of the transmitted light in the optical fiber through the interaction of the evanescent wave penetrating the optical fiber waveguide and the measured object, and measure these changes to obtain the concentration of the measured object, The method of parameters such as refractive index and pH value. When used in the fields of environment, biology, chemistry, etc., the parameters to be tested are very small, such as the content of substances, changes in refractive index, etc., such as drinking water quality measurement, DNA measurement, biological immunity measurement, etc. How to improve the sensitivity of the optical fiber evanescent wave sensor, reduce the noise, and m...

AI Technical Summary

Problems solved by technology

[0006] Researchers have adopted different methods to improve the sensitivity of optical fiber evanescent wave sensors and reduce noise, and a lot of manpower and material resources have been spent on this topic.

However, so far, it is still an unsolved problem to measure multiple parameters online with label-free (non-fluorescent) high-sensitivity evanescent wave sensors.

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