Long period fiber grating and its preparation method

Abstract

The invention provides a long-period fiber grating and a preparation method. The long-period fiber grating comprises a side-hole fiber and common fibers welded with two ends of the side-hole fiber respectively, and is characterized in that one end of the side-hole fiber is provided with a first hole (3-1), the other end of the side-hole fiber is provided with a second hole (3-2) and a third hole (3-3), three steel pipes (4-1, 4-2, 4-3) with the lateral parts being provided with through holes are vertical with the side-hole fiber, axially arranged in the side-hole fiber in a sleeved mode and fixed in the first hole, the second hole and the third hole respectively, the steel pipes and the side-hole fiber are sealed, the second steel pipe (4-2) is connected with a first micro pump (6-1), the third steel pipe (4-3) is connected with a second micro pump (6-2), and an air cavity in the side-hole fiber is injected with a first liquid (7) and a second liquid (8), which are distributed at an interval, through the first micro pump (6-1) and the second micro pump (6-2). The long-period fiber grating provided by the invention has the advantages of simple structure, easy manufacturing, low cost, ability of being used repeatedly, controllable length and period of the fiber grating, and the like.

Description

technical field [0001] The invention relates to a fiber grating, in particular to a long-period fiber grating. The invention also relates to a preparation method of the fiber grating. Background technique [0002] Long-period fiber grating is a new type of optical fiber passive device that has only appeared in recent years. It has better optical properties than fiber Bragg grating in some aspects, and has an extremely important position in the field of communication and sensing. Its application potential, such as gain flattening, dispersion compensation for fiber amplifiers, and temperature, strain, and biochemical sensors, etc. The basic light transmission principle of long-period fiber grating is the coupling between the core mode of forward transmission and the higher-order modes of each order in the same direction. The energy conversion occurs under the condition that the higher-order modes are attenuated after traveling for a certain distance, forming a loss peak. It...

AI Technical Summary

Problems solved by technology

Although this type of fiber grating has a simple structure and small size, the preparation process is complicated, the period control of the fiber grating is unstable, and the photonic crystal fiber is expensive.

In summary, no matter the traditional method of preparing fiber gratings or the combination of optical fiber and microfluidic method, there are disadvantages such as complicated preparation process and high cost.

Images