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 Post subject: Omega Bob offering SW UV isolating filters.
PostPosted: Tue Dec 22, 2009 12:09 am 
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Joined: Tue Jan 02, 2007 8:20 pm
Posts: 2658
Bob Johnson of Omega Filters has some SW UV up on ebay.
They are half inch and one inch in diameter. Notice how low the transmission is even at the wavelength you want ie. 254nm.


and here

For comparison here is Hoya Opticals pages on UV filters. Notice they don't have anything dyed in the glass that will really separate SW UV. This is the same as all the previous glass companies that used to make these things like Corning and Schott and Chance. They do have a glass that will isolate the LW UV from a mercury source but not the SW.

Here is the corresponding page from Schott Advanced Optics. Same thing.

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PostPosted: Sat Dec 26, 2009 12:48 am 
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I purchased one of these about a year ago. I think it was narrow-band filter, but I'll have to check next time I am in lab. Anyways, the small size and the dismal transmission % makes it not so useful for a mercury lamp, but it does a good job of cleaning up the output from a 250nm LED.

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