The Transitions lenses are photochromic, which is the name of the process of the lenses changing color.
Showing a demo of the lenses changing can be influenced by the material of the lens chosen , they come in Polycarbonate or CR-39 plastic, or different Hi - Index compositions. Each different material can have a slight different effect on how fast or dark it changes to compared to the demo.
The amount of UV present also affects how much a lens will change and so does the temperature.
They are just protecting themselves so someone can't claim false advertising because they don't look the same as in the ad.
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The Transitions lenses are photochromic, which is the name of the process of the lenses changing color.
Showing a demo of the lenses changing can be influenced by the material of the lens chosen , they come in Polycarbonate or CR-39 plastic, or different Hi - Index compositions. Each different material can have a slight different effect on how fast or dark it changes to compared to the demo.
The amount of UV present also affects how much a lens will change and so does the temperature.
They are just protecting themselves so someone can't claim false advertising because they don't look the same as in the ad.