A double nanostructure for wide-angle antireflection on optical polymers

Direct plasma etching is a powerful method for producing antireflective nanostructures on optical polymers, such as cycloolefin polymers. The approved process requires the deposition of a very thin initial layer followed by etching. The structure depth achievable in this way is limited to approximately 100 nm. Due to this limitation, the reflectance performance of materials produced by plasma etching is sufficient in the visible spectral range for normal light incidence on planar substrates only. By depositing and etching an additional organic layer on top of the structure, its antireflective performance can be significantly broadened. This type of double structure is adequate for light incidence angles of up to 60° on planar and curved substrates.