New transition lenses

[OptiBiz]

How long does it take a polycarbonate transition lens to clear up after being activated?
Optibiz

[Jim Schafer]

Hello OptiBiz,
Fade back time of a photochromic lens is hard to pinpoint in absolute numbers. Conditions of activation and fade are never a constant.
UV energy activates the lens and absence of UV energy plus visible light bleaches the lens to the clear state.
Transitions Polycarbonate, 1.67 Hi Index and soon to be released Trivex products have very fast activation and fade times. In ambient 73° room temperatures with good incandescent lighting ( flourescent lighting emits low level UV that partial activate lenses), these products will go from 22% Transmission to 60% Transmission in 5 minutes or less.
regards,
Jim