An optical fiber grating is a small segment within an optical fiber altered to act as a selective filter for light. This treated area functions like a specialized mirror, reflecting a specific wavelength of light while allowing all other wavelengths to pass through. This technology relies on periodic structures within optical fibers that modify the propagation of light, enabling a myriad of applications ranging from telecommunications to environmental. 📦 For purchasing, use the RP Photonics Buyer's Guide for fiber Bragg gratings. It provides an expert-curated supplier directory, buyer-focused technical background information, and structured selection criteria to support professional procurement decisions.