Analysis of optical and wetting properties of a biomimetic anti-reflective surface for practical application

In this study, moth-eye-inspired structures (MISs), which improve optical performance of surfaces, were developed to enhance light efficiency in various optical fields. As the polymer-based soft lithography process can easily optimize MIS materials and nanostructures, 12 MIS/inverse MIS (IMIS) surfaces of 300, 500, and 1000 nm composed of polyurethaneacrylate (PUA) and polydimethylsiloxane (PDMS) polymers were fabricated, and a thin octafluorocyclobutane (C4F8) layer was deposited on the surfaces to reduce their surface energies. The results showed that the 300-nm PDMS-MIS showed excellent optical properties with 94.44 % transmittance and 3.28 % reflectance. Additionally, two theoretical phenomena, the diffraction effect and double-slit diffraction, were experimentally demonstrated using three single-wavelength lasers. Subsequently, contact-angle measurements demonstrated all MIS/IMIS surfaces to possess hydrophobic and superhydrophobic properties, which can protect devices from outdoor liquids. Finally, we confirmed the applicability of MIS by attaching it to a cell phone display and an ITO glass, which is used as a substrate in various optical instruments.