Optical fiber interference water level sensor

Abstract

The invention discloses an optical fiber interference water level sensor. The optical fiber interference water level sensor is composed of a semiconductor laser device, a 3dB coupling device, a sensitive element, a Faraday polariscope, a light guide optical fiber, a photoelectric detector and a computer, wherein the sensitive element is a key part of the water level sensor and is used for converting the change of a water level into vertical strain and radial strain of the optical fiber so that the phase difference of two interference arms is changed; finally, the change of the water level is inverted by using the change of the phase difference. By the aid of the optical fiber interference water level sensor, the high-precision water level measurement can be realized, and the optical fiber interference water level sensor has the advantages of reliability, electromagnetic interference resistance, corrosion resistance, high sensitivity, simple and exquisite structure and the like, and is suitable for the environment needing high-precision water level monitoring.

Description

technical field [0001] The invention relates to the technical field of optical fiber sensing, in particular to an optical fiber water level sensing system based on a Michelson interferometer structure. Background technique [0002] High-precision water level sensors can be used to monitor the water level of reservoirs. When abnormal conditions such as floods or typhoons occur, if there is no effective water level monitoring in advance and the water level reaches the warning line, it will cause vicious accidents such as river embankment breaches and floods destroying embankments. These disasters will not only cause major economic losses , It will also threaten the safety of people's lives, so it is of great significance to the development of high-precision water level sensors. [0003] With the rapid development of optical fiber communication and optical fiber sensing technology, optical fiber sensors have also been widely used. Because the optical fiber sensor has the adva...

AI Technical Summary

Problems solved by technology

In the Chinese patent with the published patent No. CN102889914A, a float-type water level gauge using a reference water level is proposed. This float-type water level gauge has some defects. First, it is not resistant to electromagnetic interference, and the measurement accuracy is low and the error is too large , Secondly, due to the structure of the float, the float floats in the water, causing its mechanical structure to be subject to great wear and tear, and the reliability will be reduced

In the Chinese patent with the published patent number CN201731918U, an ultrasonic water level sensor is proposed, which uses the principle of ultrasonic transmission and reception to measure the liquid level. The disadvantage is that the ultrasonic transmission and reception have relatively high environmental requirements and cannot be applied In harsh or complex environments

As far as water level monitoring is concerned, these existing electrical sensors have many limitations, such as low safety, limited transmission distance, short service life, difficult networking, and inapplicability to harsh environments such as electromagnetic interference and strong corrosion.

Therefore, these water level sensors are increasingly unable to meet the needs of practical applications.

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