David Calderón from VisioramaSport explains it to us in detail!
The photochromic lenses They are characterized by being photosensitive, darkening according to the UV light intensity that affects them.
There are several colors (brown, green, gray, even mirrored) and are defined by their category at rest and their category when they are fully activated. For example, category 0 is absolutely transparent and category 4 is a special lens for high mountain.
We find photochromic lenses of Cat 0 / 3, 1 / 3, 1 / 2 and 2 / 4
Depending on the type of activity you do, your optician will recommend one or the other.
As for the speed of activation / deactivation has also evolved a lot by the manufacturers, they can move from 0 to 3 in 1 minutes 30 seconds and clarify from 3 to 0 in about 2 seconds.
Unless you look for a very specific lens for a certain sport activity, the photochromic lens is the most indicated for its versatility in any climatic condition, with what especially in long outdoor tests where the weather is variable, are your perfect ally to protect your eyes from sunlight.
Find out at VISIORAMASPORT, an optician specialized in sports glasses.
David Calderon Rodriguez
With 8017
c / Alcarria, 8 - Alcalá de Henares (Madrid)