Clearwing‐Inspired Invisible Thin Membrane

Abstract Advanced highly transparent films or membranes are required for diverse optical applications, including ophthalmology and the display industry. In general, bioinspired engineering is the most promising technology for obtaining highly transparent surfaces. This study proposes a novel perfluoropolyether (PFPE) highly transparent thin membrane with nanopatterns on both sides of the surface, inspired by the wings (clearwing) of Greta‐oto. PFPE is a superior material for achieving this goal because of its low refractive index and low surface energy. A clearwing‐inspired antireflective membrane (CAM) composed of PFPE is fabricated using a well‐designed polymer replica method. CAM exhibits outstanding optical properties and intriguing demonstrations of invisible trap sensors, both in air and water, with long‐term stability.