Graded-index AR surfaces produced by ion implantation on plastic materials.

The damage tracks of high energy ions in dielectric materials can be etched until overlapping conical etch pits are obtained. If the depth of the pits is >lambda/2, an effective graded-index layer with very low reflectivity is obtained. Broadband antireflection treatment achieving reflectivities of <10(-4) has been applied to plastics like Lexan and Mylar.