Two kinds of tension in fiber Bragg gratings with cladding etched as the sinusoidal function

Abstract

A new grating structure with cladding etched as the sinusoidal function along the length direction is introduced. The cladding area of the grating varies as the sinusoidal function along fiber axes. The coupled mode theory is used to analyze its performance. Compared with the linearly chirped grating, the new structure exhibits an ideal box spectrum with steep edges when the tension is applied on the gratings in two different ways. For the type B grating, without tension after writing, it has a bigger bandwidth utilization (BWU) than that of the type A grating with tension after writing. Compared with the type A grating, the type B one is more adaptable in fiber-optic communications and sensor systems.

Research on FBG High Temperature Sensor Used for Strain Monitoring

“…Firstly, the working condition of the electric strain gauge is not stable because the corresponding circuit is unable to work at high temperatures, secondly eclectic sparks given off from the electric strain gauge can easily result in the explosion accidents in oil and chemical environment. Fiber Bragg grating (FBG) has been one of the popular researching areas in optical fiber sensing technologies in recent years [1][2][3], FBG sensor have so many technical advantages,such as high precision, distributed monitoring ability and easy to form various forms of optical fiber sensing network [4][5][6].…”