Quote:
Originally Posted by Khaleesi Dane
This is he face shield, does it apply to the glasses as well?
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Yes, the catalog from the Oberon website says that the options are available in glasses (called Image EyeWare (tm) Spectacles).
Quote:
Originally Posted by Khaleesi Dane
From above; "Didymium glass lenses are not designed to provide protection from this radiation. Its purpose is to filter out the yellows in the visible spectrum. ".
Does this apply to our current basic purple didys? Guess I am still confused... Sorry!
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Yes and no. Glasses generally referred to as didymium these days are not what they used to be. Didymiums were the original glassworker glasses designed to reduce sodium flare, but did not provide protection. What we have now are the Schott filters, ACE 202, AuraLens 92 (and the more recent AuraLens filters) which do protect from IR. Complicating this is that the current trend is toward polycarbonate filters (e.g. Wale S and SB, and recent Phillips offerings, including shields), with glass being less and less available. (Mike Aurelius states the opinion that plastic is not as durable and is prone to fading ... paraphrased, but I don't think I am misinterpreting his words.) In summary, Oberon is speaking of the didymiums as a product, while the way you are referring to them is as a generic term for lampworking safety glasses.
Quote:
Originally Posted by Khaleesi Dane
"Didymium-2 does not provide the protection we need and Oberon does not claim it does, but claims that it uses the gold coating to do so."
This is the sentence that is confusing me.... :-/
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So, the old didymium was a glass formulation developed to cut sodium flare with no protection from IR. Oberon replicated this in polycarbonate, but it still has little protection from IR. (I'd say no protection, but their literature is a little confusing on this point.) Oberon recognizes the need for IR/UV protection, and claims the gold coating will do so. Didymium-2 (or didymium II) is an Oberon formulation. Schott/Phillips/ACE202/AuraLens are designed to both reduce sodium flare and protect from IR. (Yes, I've left out UV because this is just off the top of my head and I don't remember which ones claim to do what, but that probably isn't important right now.)
This doesn't exactly have anything to do with this topic, but since I have a place to put this, it might as well be here. I've found my folder of information on my computer and compared the AuraLens 92 chart with the Schott S8806A chart. The transmission peaks are almost exactly the same, but the AuraLens attenuates about 5% more. The Schott chart stops at 800 nm while the AuraLens chart goes to 1000 nm, but I don't believe that it definitively says the Schott filtering stops at 800 nm, just that no data is given. Both the Schott and AuraLens transmittance at 800 nm is 0%. The AuraLens chart labels hazardous IR as 950+nm, at which the transmittance is about 73% and increases from there. My opinion is that the Schott chart was intended to emhasize filtering characteristics in the visible region, whereas the AuraLens chart was intended to emphasize attenuation characteristics in the IR and UV regions (i.e., difference in intended audiences). Also based on this, the Oberon claim for IR attenuation actually looks very good.