Fabry-Perot high-humidity sensor and measuring method thereof

Abstract

The invention provides a Fabry-Perot high-humidity sensor and a measuring method thereof, and relates to the technical field of optical fiber biosensing. An incident light source is connected with aninput port of an optical fiber circulator through an incident light waveguide; an optical fiber probe is led out from an output port of the optical fiber circulator and is fixed on a sliding rail through an optical fiber fixing piece; and the optical fiber fixing piece is connected with one side of a movable reflecting surface through the two ends of a spider traction wire, and the other side of the movable reflecting surface is connected with a spring fixing piece fixed on the sliding rail through a miniature spring. According to the invention, a Fabry-Perot cavity with a variable cavity length is established by utilizing the characteristic that spider traction silk absorbs water and then is super-contracted, so that interference spectra of reflected light of the end surface of the optical fiber probe and reflected light of the movable reflecting surface have different free spectral length ranges under different humidity. The super-shrinkage characteristic of the spider traction wireis used for humidity measurement, so that the humidity sensor has the characteristics of good natural degradability, biocompatibility, higher sensitivity and higher response speed under the conditionof high humidity.

Description

technical field [0001] The invention relates to a Fabry-Perot high-humidity sensor and a measuring method thereof, belonging to the technical field of optical fiber biosensing. Background technique [0002] With the rapid development of science and technology, humidity monitoring is widely used in instrumentation, automation systems, agriculture, meteorology, geographic information and other fields, and people pay more and more attention to the monitoring of environmental humidity. Among a variety of humidity detection technologies, fiber optic humidity sensing technology has developed rapidly due to its characteristics of anti-electromagnetic interference, corrosion resistance, excellent light guiding performance, and high sensitivity. Today, under the call of green economy and green technology, the field of sensors pays more and more attention to the impact of products on human health and the environment, that is, the biocompatibility and environmental friendliness of sens...

AI Technical Summary

Problems solved by technology

In 2019, Novais et al. used agarose gel as a humidity-sensitive medium to achieve humidity detection from 20% RH to 98.5%, but the total shift of the spectrum in the entire humidity detection range was only 2.5nm, from 60% RH to 98.5%. The humidity sensitivity in the high humidity range of RH is only 44.2pm / %RH (Humiditysensor based on optical fiber coated with agarose gel, Optical Sensors, 2019)

At present, there is no Fabry-Perot humidity sensor made by using the super-shrinkage properties of spider silk, and the super-shrinkage properties of spider traction silk can shrink the length of spider silk by more than 50% under high humidity conditions, which can drive the designed Fabry-Perot humidity sensor. The length of the Riperot interference cavity achieves a shrinkage change of nearly 50%, which is larger and more obvious than the cavity length change of the traditional Fabry-Perot humidity sensor

Images