Wavelength calibration method during optical fiber Bragg grating sensing wavelength demodulation

Abstract

The invention relates to a method for on-line real-time marking the wavelength when demodulating the sensing wavelength of optical fiber Prague grating, belonging to the optical fiber sensing measure technique. Wherein, the first end of three-end optical circulator is connected to the broad-band light source, the second it connected to the optical fiber Prague grating sensor, and the third end is connected to the wavelength demodulator, to realize the wavelength mark; it uses one optical fiber Prague grating as the wavelength reference device, to be serially connected with the optical fiber Prague grating sensor, while the reference device is packed in a constant-temperature groove, whose temperature accuracy is+-0.1Deg. C; and the wavelength reflected from the reference device has stability on the spectrum; using it as norm to be arranged at the upper or lower end of Prague wavelength display spectrum of optical fiber Prague grating sensor, to mark the wavelength when demodulating the sensing wavelength of optical fiber Prague grating. The invention has simple operation and lower cost.

Description

technical field [0001] The invention relates to a method for on-line and real-time calibration of wavelength in the process of optical fiber Bragg grating sensing wavelength demodulation, and belongs to the technical field of optical fiber sensing measurement. Background technique [0002] Fiber Bragg Grating (FBG for short) is an all-fiber device formed by periodically modulating its refractive index in the core of a single-mode fiber. FBG has been used more and more widely in the fields of optical fiber communication and optical fiber sensing. FBG sensors have significant advantages such as anti-electromagnetic interference, corrosion resistance, long service life, small size, and multi-point distribution measurement by means of optical wavelength multiplexing, so they play a huge role in situations where traditional sensors cannot be used. In recent years, with the continuous development of FBG sensing technology, its application range is also expanding, and it has begun...

AI Technical Summary

Problems solved by technology

Due to the high price of the standard gas box, it is generally only used for high-precision spectral analysis instruments

In addition, using a standard gas box requires a separate photoelectric detection system, which will undoubtedly further complicate the FBG sensing wavelength demodulation system and increase its manufacturing cost

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