Metallic High Reflection (HR) Coatings

Metallic high reflection coatings are metal thin films deposited on optical substrates to increase the reflectivities of optical components (often times optical mirrors). Metallic mirror coatings reflect light because of the high densities of free electrons of metals. Metallic mirrors have limited reflectivities compared to dielectric mirror coatings, but have wider reflection spectral ranges and are less sensitive to changes of AOI.