a method and apparatus for the stabilizing of napthopyran and spiroxazine photochromic dye in a coating or plastic media is presented . as prolonged exposure to light causes degradation of the photochromic properties of the dyes , a two - tiered layering system is utilized in which a hindered amine stabilizer and / or an ultraviolet light absorber , is placed as a clear coat layer above a bottom layer containing the photochromic dyes . the bottom layer is constructed containing the photochromic dyes by either a coating of a surface of a lens or an imbuing of the photochromic dyes into the lens material , and can further optionally contain a hals and / or uv blocking compound itself .