Dual-wavelength differential temperature measuring system based on optical-fiber radiation attenuation temperature dependency

Abstract

The invention discloses a dual-wavelength differential temperature measuring system based on optical-fiber radiation attenuation temperature dependency. Once a transmission optical path is adopted, the dual-wavelength differential temperature measuring system comprises a first optical source, a second optical source, a coupler, a sensitive optical fiber, a wavelength division multiplexer, a first detector, a second detector, a detecting circuit and a computer; once a reference optical path is introduced, the dual-wavelength differential temperature measuring system comprises a first optical source, a second optical source, a first optical splitter, a second optical splitter, a coupler, a sensitive optical fiber, a wavelength division multiplex, a multi-channel detector, a detecting circuit and a computer; and therefore, the optical source interference resistance of the dual-wavelength differential temperature measuring system is improved. A reflecting device can be arranged at the tail end of the sensitive optical fiber to form a reflective dual-wavelength differential temperature measuring system. According to the dual-wavelength differential temperature measuring system, the optical fiber subjected to irradiating and annealing serves as a temperature sensitive element, and the system is simple to manufacture; and by adopting a dual-wavelength differential measurement scheme, the dual-wavelength differential temperature measuring system improves the measuring signal intensity, effectively inhibits common-mode noises in the optical path due to the bending of the optical fiber, and improves the measurement precision. The dual-wavelength differential temperature measuring system can be applied to high-precision temperature measurement.

Description

technical field [0001] The invention relates to a dual-wavelength differential temperature measurement system based on the temperature dependence of optical fiber radiation-induced attenuation, and belongs to the technical field of temperature measurement. Background technique [0002] Temperature is a fundamental physical quantity. Temperature detection plays a very important role in modern industrial systems and engineering applications. Traditional temperature sensors represented by thermocouples, platinum alloys and semiconductors have been widely used many years ago due to their simple principle, low cost and high precision, and play an irreplaceable role in many occasions. However, in the harsh environment of flammable, explosive, narrow space, corrosive environment or electromagnetic interference, the traditional temperature measurement technology is greatly limited or even unable to work. [0003] Optical fiber has the advantages of small size, light weight, flexib...

AI Technical Summary

Problems solved by technology

Since the fiber radius of the optical fiber Fabry-Perot cavity interferometric temperature sensor is only on the order of 10-125 μm, the F-P manufacturing process is complicated, and the consistency is difficult to guarantee; the change of the interference power with the cavity length is not a single correspondence, but a constant For attenuated periodic signals, the demodulation system is complex; if the wavelength domain signal is used for demodulation, the system is relatively complex; the F-P cavity length changes very little with temperature, and the sensing temperature range is very limited

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