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 an innovative Plasma Ion Immersion Deposition (PIID) coating technology for hybrid organic/inorganic-based thin films as durable adherent non-delaminating optical coatings for polycarbonate because: 1) SwRI and INTER Materials have already demonstrated the feasibility of Plasma Ion Immersion Deposition as a new technology for depositing AR optical coatings; 2) INTER Materials already has its own large 84"diameter x 60"deep vacuum chamber for PIID plasma deposition of AR-hard optical coatings for large-curved polycarbonate components located close to the Virginia Tech University campus; 3) INTER Materials has access to the state-of-the-art laboratory equipment at 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 design, engineer and build pilot capabilities at our facilities in Radford, Virginia, that will allow us to establish Plasma Ion Immersion Deposition (PIID) as an innovative coating technology to manufacture superior multi-layer graded-index AR-hard optical coatings for polycarbonate. This new plasma deposition technology will enable the fabrication of environmentally durable AR-hard optical coatings for polycarbonate that meets the Air Force specified requirements including R<0.5% and T=99.5%. 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 pilot capabilities get established for manufacturing AR-hard optical coatings, SwRI and INTER Materials have already made formal arrangements to work with a well established US supplier of eye protective solutions for aircrew to commercialize this technology.