Broadband Optical Antireflection of Plastic Optics by Molded Stochastic Sub‐wavelength Structures

Stochastic sub‐wavelength structures with lateral sizes of below 100 nm and heights of about 250 nm were produced on polymer surfaces by plasma treatment. From these master samples, an embossing nickel tool was manufactured, which, in turn, was used to replicate the master surface form by hot embossing in plastic materials. The geometry of the produced nanostructures was quantified by scanning electron microscopy. The optical surface reflectance of both the master and the replicated samples were measured in the visible wavelength range. A significant reduction of optical reflectance from the expected 4% of untreated surfaces, to less than 0.5% of the master samples, and to values between 1% and 2% of the replicated samples was achieved. The optical reflectance of the stochastic structures was calculated by a finite element‐based rigorous solution of the Maxwell equations. The modeled results show a good agreement with experimental data. magnified image