Utilizing the photo-curing characteristics of photosensitive materials, a fiber-optic-like grating polymer long-waveguide structure was constructed between two multimode optical fibers through stepwise curing. This paper employed Norland Optical Adhesive (NOA) as the photopolymerization system. Initially, the optical adhesive was applied between two aligned fibers, followed by curing with a 405 nm laser to solidify the droplets, thus forming a polymer channel between the aligned fiber cores. By applying an external force to detach one end and repeating the operation, a grating-like structure was obtained. After forming the grating-like structure, a long waveguide was further cured to complete the grating-like polymer long-waveguide. The mechanical response of these waveguides was studied. By varying the dimensions of the gratings, the optimal grating polymer long-waveguide was identified. The results indicate that the introduction of the grating-like polymer long-waveguide leads to an extremely linear trend in optical transmission with waveguide spacing. Specifically, when the grating size of the grating-like polymer long-waveguide is 5 μm, the linearity can reach above 0.99, with a strain sensitivity of 49/με.