Heliomat effect of eye glasses?

Question

i have a pair of eye glasses which have the type of lens that gets black when facing sunlight. i think it's called HELIOMAT.

they are very good and make my eyes feel a lot more relaxed. i've had them for 1 year this month, and they are great. however, i noticed that the heliomat effect has kinda worn out. they don't get so dark as before anymore. WHAT TO DO?

p.s. i heard that if you place them for 2 hours in the refrigerator, and then leave them at room temperature a couple of hours ( better to be done before bedtime), the effect re-activates the cells that make their colour change. Thus they change colour faster and darker than before. I am not sure, though.

Answer 1

The correct name for these type of lenses are photo-chromatic: Heliomat, transitions, reactors are all brand names; they do tend to have a shelf life of approx 2 years in which time they will start to slow down and have a slight permanent tint to them. Photochromic lenses react best to direct UV light and cold temperatures. So storing them some where cool before you leave your house will help in the reaction time. However, you will notice that over time they will become slower and slower.

Answer 2

They are Transitions, or Colormatic lenses. ( different companies) both are of the photochromic family of lenses.

No, freezing them or even putting them in the fridge won't do anything to reactivate them...

Leaving them under a UV light for a few hours sometimes helps though.