Micro-displacement Measurement Method Based On Tilted Fiber Bragg Grating

Fiber gratings have a comprehensive prospect in optical communication and sensing systems, due to their excellent optical properties. However, Tilted fiber Bragg grating, an important member of fiber gratings, has been paid much attention for its special structure. In past twenty years, the theoretical and experimental study on TFBG has made some achievements, and it also has been used in the area of optical communication, sensing system and wavelength demodulation.We give a micro-displace measurement method in this paper, based on the study of Tilted fiber grating. The contents are listed as follows:At first, a brief introduction of structural characteristics of TFBG and its history is presented. Its application of optical communication, sensing system and wavelength demodulation is illustrated with an example.Secondly, three theoretical methods used to study in the present period, including their advantages and disadvantages, and applications, are summarizes. Using coupled mode theory and volume current method analyses characteristic of the radiation and reflection in titled fiber Bragg grating. Parameters for TFBG used in the article are given on this basis.Thirdly, the new demodulation system is designed, after theoretical analysis on side detection of strong radiation-mode method based on TFBG,the demodulation system with such method has the ability of simplicity, stability and repeatability.