Theoretical And Experimental Research On MLPFG Under Complex Stress

The optical communication network constituted by lots of active and passive devices.Especially the LPFG(long-period fiber grating)is one of the passive device which used frequently.The research about the LPFG become more and widely.The study both in theoretic and in experiment are comprehensive.In this paper,the study of MLPFG characteristics is divided into mechanical part and optical part.These two parts are both studied by different methods.By comparing the different methods,a suitable way is chosen for building the theory analysis model of MLPFG.A simple forced type MLPFG was design for constituting a band-rejection filter,which can be used to adjust the grating period and the transmittance.And the attenuation peak near 1550nm can be obtained while the? = 600?m-675?m,the transmittance could reach-10?-20dB with the external force of 50N.At the same time,the MLPFG of the structure was analyzed and calculated by the theoretical model.It was found that the theoretical model has high accuracy and less error by comparing with the experimental result.By improving the grating groove structure of the simple forced type MLPFG,the position of the fiber was stable during work and the grating period was not easy to change.And a six-point forced type MLPFG structure is proposed.Through the comparison with the experimental results,the theoretical model established in this paper has been applied and popularized,which could provide effective support for studying the mechanical characteristics and transmission characteristics of the MLPFGs.