How much uv protection do you get with polycarbonate lenses?

Question

Is it more than lenses dipped in a uv solution? Also do any lenses protect more than 65% of the uvb. Most seem great for uva, but not on uvb- thanking you in advance. I must say, I'm really impressed with some of the answers on yahoo.

Answer 1

Polycarbonate lenses block 99 - 100% of both UVB and UVA just by the nature of the material itself.

CR39 lenses that are soaked in UV solutions give the same protection.

The solutions block all UV rays from 290 nm to 400 nm

UVB is from 290 nm - 320nm....UVA is from 320nm to 390 nm

So all bases are covered.

I called 3 labs that manufacture UV solutions for the optical industry and they all said the same thing, so I guess they are right.

99% to 100% is  of both types of UV rays are blocked in either type of lens .

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EDIT ****

The numbers are a scientific measurement system of the wavelength of those specific rays.  In Nanometers.

Thats why it is called UV 400...it blocks rays up to the 390nm range. Rounded off to 400 only because it sounds better.

From 390 - 770 nm...is the visible light spectrum...over that is in the infra red.

UV  rays over 400 nm or below 290 nm aren't dangerous.

The UV rays take on  different characteristics when not in the 290 - 390 range and no longer pose a health risk.