Flat diffraction grating

NIRIRpolychromatic light

Ruled diffraction gratings separate polychromatic light (white light) into its component wavelengths. Straight and parallel grooves are ruled into the surface of an aluminium coated substrate at 300 to 1200 lines per millimetre. Ruled diffraction gratings are used particularly in the NIR and IR range because of the larger spaces between lines, whereas visible and UV applications suffer from stray-light and ghost spectra. Generally, ruled gratings have a higher efficiency than other types of diffraction grating and are well suited for high precision applications.