The only thing that Gemstone has NOT mentioned is that the famous clear UV solution stops absorbing UV at 382nm.
Every plastic lens today absorbs UV up to 365 nm. (called UVB) Those are the wavelength that create direct burns, skin and eyes, specially around 324nm.
UV A that reaches from 360 to 400 nm is the culprit that will provide long term damage to the eye, for example cataracts etc.
Now if you are sick and the doctor prescribes a drug whose taste you do not like...........are you just not going to take it or you only take half of it?
A clear UV gives you only protection to half the wavelength it should, namely 382nm and NOT 400nm. At 400nm the visible light starts and to compensate for the first bit of blue light some yellow is added.
A clear UV treated lens is not worth the money spent for the treatment, because it stops protecting half way between 360 and 400nm.
Some companies even sell UV meters that will show a full 100% protection at 382nm.
Of course there are thousands of opticians and optometrists that agree that the yellowish tinge of a full 400nm absorbing lens is esthetically not nice, so they choose the lesser protection over just giving the lens a cosmetic tint to make it look better.
Some years ago I wrote an article on the subject that got printed in optical magazines in many countries. You can look it up at:
http://optochemicals.com/prism_article.htm
:hammer:
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