Have a patient that wants UV and glass lenses. I foolishly thought it could be added to glass.
Lab tells me no, someone know something the lab doesn't?
Chip
Have a patient that wants UV and glass lenses. I foolishly thought it could be added to glass.
Lab tells me no, someone know something the lab doesn't?
Chip
Use either PGX or 1.6 glass.
DragonlensmanWV N.A.O.L.
"There is nothing patriotic about hating your government or pretending you can hate your government but love your country."
There are coatings available.Originally Posted by chip anderson
RGPs
ok, how about http://www.thorlabs.com/newgrouppage...tgroup_id=3569
Last edited by braheem24; 09-20-2011 at 12:51 PM. Reason: decided to be helpful
North American Coating Lab.
http://www.nacl.com/index.php?option...id=6&Itemid=87
Use 1.6 glass. UV coatings on glass give you a horrible yellowish/brownish/greenish hue that's nearly 30% - looks horrid.
I think you'd be best with a PGX lens for UV absorption, if you are not after a sun-glass.
i think this will help solve the problem
Glass has absorbed UV forever. Have you ever got a sunburn behind your car windshield ? Are you photochtomatic lenses activating behind closed windows?
Ophthalmic glass absorbs very little UV. Hoya, a long time ago, brought out some special UV absorbing glass lenses. IIRC, they absorbed only abut 12% of the UV, only a slight increase over regular crown. I'll check to see if i still have any lying around and test them.
DragonlensmanWV N.A.O.L.
"There is nothing patriotic about hating your government or pretending you can hate your government but love your country."
Add AR to it. No UV
Tested with a Phantom UV 400udx unit. Lenses were not clean to perfection, I might add.
surfaced crown: UV transmission 87%
PGX: Uv transmission 24% reducing to 8%
AR coated crown: 73%
Crown FT: 86%
Crown tonelite#1: 13%
Umbral 85(Zeiss): 1%
Stock 1.49 SV: 95% Buchman, Ao Masterpiece SV: 91%
1.7 Glass AR: 65%
Add AR to it . NO UV
Could you please elaborate? You have me confused.
65% block http://www.tru-vue.com/Tru-Vue/Products/museum-glass/
another better possibility http://www.evaporatedcoatings.com/glass-substrates.htm
http://www.opticalcoatings.com/processes/glare.html
while these sites don't specialize in lenses but in things like monitors , I don't know why they couldn't coat lenses.
Last edited by rdcoach5; 09-24-2011 at 08:56 AM.
Thanks, rdcoach5, for replying. I now understand what you were saying. The 65% cut still means a 35% transmission, though.
The way I see it:
Optical quality glass, because of it's chemical composition(s), transmits more UV than automotive, plate, and industrial glass, and therefore, any attempt to fully block UV, in spectacle lenses must involve a tint, and the maximum I recorded is 65% block with a 1.7 index AR. Now, a Tonelite#1(non-coated) recorded an 87% block, PGX recorded a better block, especially activated.
Thanks, rdcoach5, for replying. I now understand what you were saying. The 65% cut still means a 35% transmission, though.
The way I see it:
Optical quality glass, because of it's chemical composition(s), transmits more UV than automotive, plate, and industrial glass, and therefore, any attempt to fully block UV, in spectacle lenses must involve a tint, and the maximum I recorded is 65% block with a 1.7 index AR. Now, a Tonelite#1(non-coated) recorded an 87% block, PGX recorded a better block, especially activated.
When I go to these web sites, it looks like they can design their AR stack to block pretty much what they want. Maybe someone in the lab side can respond to this? I sent e-mails to Zeiss and SLC to get their response. I'll let you know what they say.
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