Blue Light Filter Test Kit

Hello, I have a question about blue light coatings. A patient came in wanting a blue light filter for their eyeglasses. We sell mostly essilor lenses. The first thing I thought of was Crizal Prevencia . The patient had a blue light test kit. (a small pen light and a test card). He had a pair of $16.00 clear plano computer glasses that were designed to block 100% blue light. We test the glasses with his checker and the test card did not turn dark. We tested a Prevencia sample and the card turned dark. I called my essior rep and he said prevencia blocked 20% blue rays and Essilor doesn't not make a 100% blue blocker. I tested a yellow sunglass lens with his test light and the card turned dark.
What do you think of these test kits? What kind of light are they emitting? Specs?
Does anyone make a 100% blue blocking coating that we can use on lined bifocal? Would 100% blue blocking be beneficial.

Thanks in advance!

You want to block 100% of light up to what? 520nm? That is going to be a very strongly tinted lens. There is a whole lot of things that don't make sense in your question.

So people are walking around with blue light test kits now? Good grief.

You need to know what spectrum the pen light is emitting. Did you try testing a poly lens?

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Originally Posted by Alex Camblor

You need to know what spectrum the pen light is emitting. Did you try testing a poly lens?

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+1, need to match the lens materiel as well.

:nerd::giggle:

Looks like they are a blue pointer 405 nm +/- 10nm I have one and shone it through a blue protect lens it goes through as normal I have done the same with a Essilor blue protect lens which let the light through also...
I have a cheap set of blue protect glasses ( lenses have a slight tint maybe 5% abs) and they block almost all the blue laser..

Well, then, if you're looking at a blue laser, those are the glasses for you!

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Originally Posted by drk

Well, then, if you're looking at a blue laser, those are the glasses for you!

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Folks. THIS^^^

Please for the love of Zeus - STOP STARING INTO BLUE LASERS! All other blue light is, for dispensing purposes, HARMLESS.

The End.

:cool:

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Originally Posted by Uilleann

Folks. THIS^^^

Please for the love of Zeus - STOP STARING INTO BLUE LASERS! All other blue light is, for dispensing purposes, HARMLESS.

The End.

:cool:

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I feel this way too!

But........ those customers keep coming in with the "stuff" they learned on the internet. So while we will gently explain what we know, most people don't care and have already made up their minds.

So it would be really useful to have our facts well-understood by everyone, which lenses block what particular parts of the spectrum, and what these "testers" ( I haven't seen any yet ) are testing.