High temperature sensor based on high germanium-doped optical-fiber temperature-measuring micro-probe

Abstract

The invention discloses a high temperature sensor based on a high germanium-doped optical-fiber temperature-measuring micro-probe. The high temperature sensor is composed of a broadband light source, an optical fiber circulator, a single-mode optical fiber, a butterfly-shaped awl, a high germanium-doped optical fiber, an optical fiber spectrometer and a high-temperature constant-temperature test box. The extremely short high germanium-doped optical fiber is innovatively welded to the end surface of the single-mode optical fiber in a butterfly-shaped mode, by utilizing a large refractive index difference between the fiber core and coating layer of the high germanium-doped optical fiber, an appropriate free spectral range is obtained under the condition that the probe is extremely short, and the effect of increasing the interference contrast degree is taken by changing parameters of butterfly-shaped welding. Thus, the high temperature sensor with the temperature-measuring micro-probe is formed and is novel in structure, the upper limit of temperature measurement is about 600 DEG C, and the high temperature sensor is applied to measurement of temperature points. In this way, the high temperature sensor has the advantages of being extremely small in probe size, high in flexibility, high in signal-to-noise ratio and sensitivity, and especially suitable for the measurement of the temperature points.

Description

technical field [0001] The invention belongs to the technical field of optical fiber high-temperature sensing, and in particular relates to a high-temperature sensor based on a high-germanium-doped optical fiber miniature temperature measuring probe. Background technique [0002] Compared with thermocouple temperature sensors, optical fiber temperature sensors have smaller probes, are immune to electromagnetic interference, have a longer service life, and are suitable for measuring small temperature changes. In recent years, related research on them has continued to deepen. [0003] At present, various temperature sensors based on fiber gratings and long-period fiber gratings have been practically used in special fields, but the temperature sensitivity of fiber gratings is low, usually only about 10pm / °C; although the temperature sensitivity of long-period fiber gratings is somewhat Boost is also very sensitive to fiber bending and external refractive index, and cross-sensit...

AI Technical Summary

Problems solved by technology

[0003] At present, various temperature sensors based on fiber gratings and long-period fiber gratings have been practically used in special fields, but the temperature sensitivity of fiber gratings is low, usually only about 10pm / °C; although the temperature sensitivity of long-period fiber gratings is somewhat Improvement, but it is also very sensitive to fiber bending and external refractive index, and cross-sensitivity of other factors cannot be avoided

Furthermore, neither probe volume meets the requirements for temperature "spot" measurements

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