Nov 23, 2016 | I had a great question from a patient this week "I used to tint the lenses in my old glasses to be my prescription sunglasses... can I still do that?" I have been practicing for over 20 years and tinting old lenses was a very common thing... so what changed as tinting is rarely done these days!? The answer is two parts: lens materials and coatings. #1 spectacle lenses are more-and-more being made from materials that just do not tint well e.g. poly-carbonate or hi-index plastics #2 the increased prevalence of anti-reflective coatings and tough anti-scratch coatings. These coatings harden the lens surface and make it impenetrable to tints. To tint a lens these days, the tints are applied prior to these coatings being applied. Dr.j Studioeyecare.com