US Patent 10175390 Face protective optical element

An optical element is provided which reflects a reduced amount of light even under a very high intensity lighting system used for a surgical operation, a dental treatment etc., has anti-fogging performance, and is transparent and useful for face protection. The optical element has a flexible transparent substrate and a plurality of structures disposed on opposite surfaces of the substrate at a pitch equal to or less than the wavelength of visible light. The structures are formed from a cured product of a resin having a hydrophilic functional group.