Trends in fiber optic sensors and applications

In recent years, the sensor toward the sensitive, accurate, adaptable, compact and intelligent direction. In this process, fiber optic sensors that a new family of sensors acclaimed. Fiber has many excellent properties, such as: anti-electromagnetic interference and radiation properties of atoms, small diameter, soft, light weight, mechanical properties; insulation, no induction of the electrical performance; water-resistant, high temperature, corrosion and other chemical properties, It can reach a place in the human (such as high temperature or harmful to people in areas such as nuclear radiation area), play a role in people's eyes and ears, but also beyond the limits of human physiology, the recipient's sense of feel outside information.
Basic working principle and applications

The basic working principle of fiber optic sensors is the light from the light source through the optical fiber into the modulator, the measured parameters and the interaction of light into the modulation region, the resulting optical properties of light (such as light intensity, wavelength, frequency, phase, Polarization-state, etc.) changes, known as the modulated signal light, after the fiber into the optical detector, the demodulated to obtain the measured parameters.

Fiber optic sensor applied to the magnetism, sound, pressure, temperature, acceleration, top, displacement, surface, torque, light sound, current and strain and other physical measurements. Fiber optic sensor wide range of applications, involving almost all the important economic and defense fields and people's daily lives, in particular, can safely and effectively in harsh environments, to solve a number of industries over the years there has been technical problems with great market demand. Mainly in the following areas of application:

● urban construction, bridges, dams, oil and other grating interferometer gyroscope and pressure sensor applications. Fiber optic sensors can be embedded in the concrete, carbon fiber reinforced plastics and various composite materials for stress relaxation tests, dynamic load stress and the stress of construction, to assess the short-term bridge construction phase and long-term operating performance of the state structure.

● in the power system, need to determine the temperature, current and other parameters, such as high voltage transformers and large motor stator, rotor temperature detection, the electrical type sensors susceptible to electromagnetic interference, can not be used in such cases, only with fiber-optic sensors. Distributed optical fiber temperature sensor is developed in recent years as a space for real-time measurement of temperature distribution in high-tech, distributed optical fiber temperature sensing system not only has the general advantages of fiber optic sensors, also has various points along the fiber temperature distribution of sensing capabilities, we can use this feature along the continuous real-time measurement of optical fiber point temperature within a few kilometers, the order of positioning accuracy can be Damien, measurement accuracy of up to 1 degree level, ideal for a wide range of temperature of the intersection applications.