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In this paper, a novel vertical-pendulum-based inclinometer based on fiber Bragg grating (FBG) is proposed. Using the pendulum system, which consist of a blade edge and a V-shaped groove, the damping of the rotation system can be greatly reduced. Owing to the advantages of the rotating structure, a sensitivity of 78.3 pm/° and a resolution of 0.013° have been achieved.

A method of measuring distributed strain over 25 km in single-mode fiber with a high sensitivity is presented in this paper. By eliminating the laser phase noise, 2.5-m spatial resolution and 58-ne strain resolution are achieved.

In this paper, a vibration detection system based on the phase-sensitive optical time domain reflectometer and the optical fiber Michelson interference is proposed for the electrical discharge localization systems of the Gas Insulated Line(GIL).

This paper presents a high sensitive curvature sensor based on a dual core photonic crystal fiber (DCPCF). Its curvature sensitivity reaches 7.3235 nm/m−1, within the measurement range of 0.3078-0.9235 m−1.

We have monitored on-line the spectral characteristics of two lines of five multiplexed Fiber Bragg Gratings under high temperature and high neutron fluence (up to 670°C and 3×1019 nfast/cm2>1Mev). The gratings have been written using a femtosecond laser and the point-by-point technique onto pure silica core (PSC) single-mode fibers. This paper details the evolution of the Bragg wavelength shifts (BWS) during the irradiation conducted at the MIT Nuclear Research Reactor.

This paper conducted a measurement method for mining overburden deformation monitoring with the distributed optical fiber sensing technology, which precisely detects the rock mass destruction and stratum structure forming with the Brillouin frequency shifts characterization.

This paper proposed a novel ultrahigh-resolution optic fiber temperature sensing technique. The free spectral range of a fiber Bragg grating resonator is experimentally calibrated for temperature measuring with a narrow linewidth tunable fiber laser. The results show that this method has a high temperature sensitivity and can effectively eliminate the influence of the frequency instability of the laser source. A temperature resolution of 0.11 mK with good long term stability is demonstrated.