Research On Tilted Fiber Bragg Grating And The Demodulation Technology Of Fiber Bragg Grating

As novel passive optical components,fiber gratings have a comprehensive prospect in optical communication and sensing systems,due to their excellent optical properties. Tilted fiber Bragg grating,an important member of fiber gratings,because of its special structure,not only has all properties of fiber Bragg grating,but also has its own unique properties.Now a group of researchers have made their best effort on its applications and it have been used in the area of gain flatten,sensing system and wavelength demodulation.A brief introduction of history,research significance is presented.Three mature technologies of wavelength demodulation,their own characteristic have been recommended and the history of tilted fiber Bragg grating,its sensing characteristic and wavelength demodulation characteristic have been presented here.Using coupled mode theory analysed the mode transmissive characteristic in tilted fiber Bragg grating.The wave equations,modes coupled coefficient and Poynting vector have been got here.The sensing theory of tilted fiber Bragg grating is presented here.Theoretical and Experimental research on its temperature sensing characteristic,strain sensing characteristic and refractivity sensing characteristic have been taken.The tilted fiber Bragg grating has the same temperature sensing and strain sensingcharacteristic as fiber Bragg grating.The transmission power of the tilted fiber Bragg grating decreased linearly with the environment refractive changed and the sensitivity came to 1.718μW/ (10^-3 index changed).Theroecally analysis the principle of edge filtering of TFBG dumped in glycerite which is used as edge filterer.It has been proved in the experiment that the demodulation system with TFBG has a good property of wavelength linearly. There are different positions pointing to the differnet wavelengths of theincident light which comes into TFBG and it has been proved in the experiments.The FBG demodulation system with such method has the ability of simple,stable and repeatble.A brief introduction of Bluetooth,This paper reseaches on the wierless smart sensor system which conbine Bluetooth wierless sensor technique,and has desinged a wireless smart sensor model.It has wireless conmmunicating baility.