Organic&Hybrid Organic/Inorganic-Based Graded-Index/Layered Optical Coatings by Physical Vapor Deposition (PVD)

ABSTRACT: One of the Air Force main interests is to improve the antireflective (AR) optical properties of polycarbonate by exploring new coating materials or coating techniques to eliminate delamination and stress cracks due to the mismatch in the coefficient of thermal expansion between the coatings and the polymer substrates. SwRI and INTER Materials are in a unique position to assist the Air Force with the development of a novel Plasma Ion Immersion Deposition (PIID) coating technology for hybrid organic/inorganic-based optical thin films as durable adherent non-delaminating coatings for polycarbonate because: 1) SwRI and INTER Materials have experience with PIID coatings for abrasion protection of polycarbonate and acrylic windscreens for rotary wing aircraft; 2) INTER Materials already has its own large 84"diameter x 60"deep vacuum chamber for PIID plasma deposition of AR-hard thin film optical coatings for large-curved polycarbonate and acrylic components located close to the Virginia Tech University campus; 3) INTER Materials has access to the state-of-the-art laboratory equipment at SwRI and ICTAS for the characterization of AR coatings and thin films; and 4) INTER Materials has been working closely with Dr. Kent Coulter and Dr. Ronghua Wei at SwRI, recognized world experts in the field of plasma deposition. BENEFIT: Southwest Research Institute (SwRI) and INTER Materials propose to investigate a novel Plasma Ion Immersion Deposition (PIID) thin film coating technique that will meet the Air Force requirements for developing an environmentally durable coated surface onto polycarbonate substrates with optimized AR optical properties. An innovative multilayered coating will be investigated using PIID to custom design the adhesion, hardness, and optical properties of the new AR optical surface coating. Our research indicates that an abrasion resistant and optically reflective surface coating can be deposited on a polycarbonate substrate using a technology that SwRI and INTER Materials have been using for improving the abrasion resistance on aircraft windscreens. Because the proposed technology will utilize current aircraft windscreens manufacturing infrastructure, it is predicted to have a good commercial potential and a low investment risk when adopting the new environmentally durable organic/inorganic antireflective (AR) coating technology with controlled thickness, minimal stress, minimal water content and controlled porosity. Should this concept prove successful, SwRI and INTER Materials have already made formal arrangements to work with strategically placed aircraft transparency suppliers and recognized transparent armor manufacturers to commercialize this technology.