Optical properties: the transmission is ~90% through a 6mm layer (including Fresnel losses) and is fairly featureless between 400 and 900 nm, though it drops rapidly at short wavelengths, and rises at longer wavelengths [Lowry, JH: Optical Characteristics of Teflon AF fluoroplastic materials, Optical Engineering, 31(1992), 9, 1982-1984].
Teflon AF is available in various grades. Commonly used are AF 1600 and AF 2400. AF 1600 is sold as a 6% solution in Fluorinert FC75, or as a white powder. The number after the AF represents the glass transition temperature (160 and 240 degrees Centigrade respectively). The lower the transition point, the more traditional Teflon (tetrafluoroethylene, TFE) is in the polymer, and the more soluble the resulting product is in fluorinated solvents (eg. those sold as Fluorinert by 3M). AF 1600 contains less than 40% TFE, the rest of the polymer (copolymer) is PDD, a ring shaped monomer.
Teflon AF can be spin coated, but needs baking afterwards. Adhesive films can by evaporated onto substrates. It is claimed that the refractive index of the film can be varied by altering the substrate temperature during evaporation.