科研之友
微信
新浪微博
Facebook
分享链接
摘要
We prepared porous antireflection surfaces from spin-coating of poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) latex particles onto bare glass slides. Optical properties resulting from two different coating structures, multilayer and submonolayer of latex particles, were studied depending upon the particle size. In both cases, the characteristic matrix theory based on the classical Fresnel coefficient of reflection applied to estimate the effective refractive index and thickness of the porous coatings from experimentally measured reflectance spectra. The particle fraction in the coatings was estimated by using a volume-averaged refractive index. For porous multilayer coatings prepared from 47 nm PTFEMA latex particles, it was found that the effective refractive indices (n(eff) similar to 1.34) and reflectance minima (R-min similar to 0.7%) were almost constant and independent of the coating thickness. On the other hand, the effective refractive indices were strongly dependent on the coating conditions in the case of submonolayer coatings of 140 nm PTFEMA latex particles. As increasing the solid content of the coating solutions or, equivalently, as increasing the particle fraction in the coatings, the effective refractive indices increased. The minimum specular reflectance was as low as 0.2% when the particle volume fraction in the coating was 0.40.
- 出版日期2008-11-25
