Temperature sensor based on Sagnac interference and ring cavity ring-down spectroscopy technologies

Abstract

The invention relates to a temperature sensor based on Sagnac interference and ring cavity ring-down spectroscopy technologies. The temperature sensor comprises a DFB fiber laser, a polarizer, an electro-optic modulator, an isolator, a ring-down loop, and a photoelectric detector that are arranged successively along a light path direction. The ring-down loop consists of a first coupler, a second coupler, a Sagnac interference ring, a circulator, a filter, an EDFA amplifier, and a third coupler that are arranged successively along the light path direction. After pulsed light generated by the photoelectric detector passes through the isolator, the light enters the ring-down loop from a one-percent input terminal of the first coupler; the pulsed light circulates in the ring cavity for one cycle; the part of energy is outputted by a one-percent terminal of the third coupler; and the photoelectric detector converts the energy into a voltage signal that is displayed by an oscilloscope. The sensitivity of the temperature sensor is improved by dozens of times.

Description

technical field [0001] The invention relates to an oscilloscope detecting temperature sensor, in particular to a temperature sensor based on Sagnac interference and ring cavity ring-down spectrum technology. Background technique [0002] At present, the sensitivity of temperature sensors based on fiber gratings is too low, only about 10pm / ℃. The sensitivity of temperature sensors based on long-period gratings is relatively high, but there are problems of cross-sensitivity to bending and external materials. Based on fiber optic Mach-Zehnder interferometers Or the temperature sensor of the fiber optic Michelson interferometer is cross-sensitive to external vibrations. Although compared with the above temperature sensors, the temperature sensor based on a single Sagnac ring interference has a stronger ability to resist external interference, but its sensitivity is usually only about 1nm / °C. Therefore, developing an optical fiber sensor with higher sensitivity has become an urg...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to develop a temperature sensor based on Sagnac interference and ring cavity ring-down spectroscopy technology in order to solve the technical problem that the sensitivity of the current optical fiber sensor is not high

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