Durable, Index Matching, Coatings for Low Cost AlON Finishing

Triton Systems proposes a nanoparticle-enhanced polymer coatings approach to significantly reduce the costs associated with polishing and finishing of large area AlON windows. We will develop novel, high refractive index (RI) coatings that will match therefractive indices of aluminum oxynitride (AlON), spinel, and other transparent armor ceramics. This solution-based coating will be able to fill/level the surface imperfections of unfinished or partially finished AlON and provide an optically smoothsurface in a single coating step. This will significantly reduce the time, number of steps, and the cost of finishing these high hardness ceramics. We will use Triton's low viscosity solution-based NanotufT abrasion-resistant coating as the platform, andthen incorporate surface-compatibilized nanoparticles to tailor the specific optical and other properties of the coating system. We will achieve index-matching by controlling the index and concentration of the nanoparticles, and will thus design coatingsystems with indices ranging from 1.46 to ~1.9. This range of indices will be used to form graded index and other coating systems with anti-reflection properties. The mechanical properties of the coatings will also be tailored by using this approach.Our approach will make these materials economically viable for a variety of military and civilian applications.Reduced cost, large area AlON windows will see application in variety of military, law enforcement, safety and other civilian applications. Thevariable index coatings developed here will be useful for a wide range of optical coatings and high index materials may be of use in electro-optic devices.