OPTICAL TRANSMISSION ELEMENT, HAVING A SUPER-HYDROPHOBIC NANOSTRUCTURED SURFACE HAVING AN ANTI-REFLECTIVE PROPERTY AND COVERED WITH A COMPLIANT HIGH-DENSITY THIN FILM DEPOSIT

摘要

Optical element (10), which is transparent at an operating wavelength λ, having a super-hydrophobic nanostructured surface (4) and having an anti-reflective property, said surface comprising an array of pads, characterised in that the pads have a nanometric width, a height h, an aspect ratio less than 1/2 in that the pitch p of the array is such that p h, and in that the element comprises an upper layer (5) with a thickness less than h/5 which continuously and compliantly covers the nanostructured surface, the upper layer being obtained by an annealing step at a temperature between 500°C and 1200°C and being made of a material with a density greater than the density of the material of the nanostructured surface.