SUNBOND OPTIX / LENS TESTING The first batch passing tells you the formula works. It does not tell you the hundredth batch will. A photochromic lens is not a coating with a colour in it. It is a chemical system that has to take in UV, change state, and come all the way back, tens of thousands of times. How well it does that is decided during manufacture. Dye concentration. Imbibing time and oven temperature. Resin lot. Cure schedule. Coating thickness. Every one of those move

Which means it does not reach final test until it is coated either. Anti-reflective coating can change how a lens behaves under impact. That is why the impact test has to come after the coating goes on, not before. The standards are explicit about it. ISO 8980-4 requires at least twenty four hours to elapse after coating before any type test is carried out - an acknowledgement, written into the text, that a freshly coated lens is not yet a finished one. EN 168 and ISO 12312-1