▎ 摘　　要

NOVELTY - The method involves fixing a polyimide optical fiber (1) to an optical fiber fixing base (23). The motion parameters of the polyimide fiber and the working path and moving speed of an UV laser (22) are set. The first processing parameter of the UV laser is set. The laser focus of the UV laser is positioned on the axis of the polyimide fiber. The polyimide fiber is moved according to the motion parameters, and the UV laser is configured to operate according to the working path. The second processing parameters of the UV laser are set. The defocus amount Z2 is set, the laser focus is moved according to the defocus amount Z2, and the laser focus is moved up above the upper surface of the polyimide fiber. The polyimide coating of the polyimide fiber is processed by dispersing the laser light emitted by the UV laser to form a graphene coating (5) corresponding to the position of the grating. The performance testing on the polyimide fiber is performed. USE - Method for preparing long-period fiber grating with graphene coating. ADVANTAGE - The same polyimide fiber is processed by UV laser step by step, reducing the delicate and complicated operation of transferring graphene to quartz fiber. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a device for preparing long-period fiber grating with graphene coating. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the installation of polyimide fiber. Polyimide optical fiber (1) Graphene coating (5) UV laser (22) Optical fiber fixing base (23) Displacement platform (24)