A Black Metal-dielectric Thin Film for High-contrast Displays

We demonstrate a thin metal-dielectric structure that delivers low reflection and high absorption over the entire visible spectrum. The thin black film consists Of SiO2/Cr/SiO2/Al layers deposited on a glass substrate. The measured reflectance and absorptance of the black film are 0.7% and 99.3%, respectively, when averaged over the range 380 - 780 nm. The total thickness of the black film is only about 220 nm, and it can be used as a thin absorbing layer for displays that require both broadband antireflection and high-contrast characteristics.