Parallel remote optical fiber sensing system for detecting various gas refractive indexes

Abstract

The invention provides a parallel remote optical fiber sensing system for detecting various gas refractive indexes. The parallel remote optical fiber sensing system comprises a broadband light source, an optical fiber beam splitter, optical fiber couplers, optical fiber sensors and a photoelectric detection array. The broadband light source is connected with an input port of the optical fiber beam splitter. Output branches of the optical fiber beam splitter are in cascade connection with input ports of the multiple optical fiber couplers. Each optical fiber coupler is connected with one optical fiber sensor. Each optical fiber sensor comprises a plurality of parallel optical fiber sensing probes. The photoelectric detection array is in cascade connection with the output ports of the optical fiber couplers. The optical fiber sensing probes corresponding to the optical fiber couplers are plated with different metal and / or chemical films respectively. According to the parallel remote optical fiber sensing system, simultaneous detection of remote multiple gases and external refractive indexes can be achieved, the optical fiber sensing probes are in an upward-expanding tapering refractive optical fiber ellipsoidal shape, the overlapped area of a wrapping optical field and the external world is increased, and the sensitiveness of the optical fiber sensing probes is improved.

Description

technical field [0001] The invention belongs to the field of sensing technology, and in particular relates to a parallel long-distance optical fiber sensing system for detecting the refractive index of multiple gases. Background technique [0002] Sensing technology is one of the industrial foundations of the information industry, especially the Internet of Things technology. The sensors currently used for gas detection mainly include traditional chemical sample analysis methods, electrochemical sensor detection, spectrometry and surface acoustic wave integrated sensor methods. [0003] The traditional chemical sample analysis method needs to operate various chemical processes on the sample, and the detection speed is slow and complicated, and the safety is poor. Electrochemical sensors need to be measured at a certain thermal temperature, and at the same time, they are interfered by factors such as electromagnetic fields, and it is not conducive to networking travel sensor...

AI Technical Summary

Problems solved by technology

The spectral imaging method requires a particularly expensive broadband light source or a tunable laser to scan the gas absorption spectrum, which is bulky, expensive, and slow in measurement speed

Some optical fiber gas sensors, such as coated long-period gratings, but the production cost of long-period gratings is relatively high, and at the same time, they cannot be disturbed by external interference such as bending. If multiple gratings are used, a broadband light source is required, and the price is also very expensive, which is not suitable for practical applications. use

Although the detection sensitivity of the surface acoustic wave sensor is very high, it has particularly strict requirements on integrated processing, and the signal drive and detection are also relatively complicated. At the same time, it is not possible to perform long-distance network detection.

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