At its core, a grating is an optical component that diffracts light into various beams based on its wavelength. Classic gratings are typically made from a single material, such as glass or plastic, featuring a periodic structure that can scatter light in specific directions. Composite gratings, however, integrate multiple materials with varying refractive indices, allowing more complex interactions with light. By cleverly designing these interactions, researchers can engineer gratings that offer improved efficiency, reduced losses, and enhanced spectral performance.
