Jetbeam        
Results 1 to 8 of 8

Thread: 365nm UV LEDs???

  1. #1

    Default 365nm UV LEDs???

    Hey guys, Iím wanting to make a UV LED flood light and Iím having trouble finding some true 365nm LEDs
    I know thereís plenty of UV cobs, strips, crees on ebay BUT thereís a lot of bogus ones there too as the majority of them are 395nm.
    Strips would be the best for mounting and wiring but unless I can get ultra bright LED strips then Iíll have to go several crees or a couple of cobs.
    Iíve used a 100w uv cob light before but you get a lot of visible light that kills the glow effect so I'd say that light would be 395nm.

    Anyone know where I can get genuine 365nm ones from? any type: cobs, strips, cree
    Cheers

  2. #2

    Default Re: 365nm UV LEDs???

    All over Ebay. You are correct that 395nm is really violet and visible, 365nm is UV. But note the 365nm will not put out the same optical power, glowing things will be brighter under the 395nm. And note even the 365nm has some non-UV light, you'll need a filter for real black light.

  3. #3

    Default Re: 365nm UV LEDs???

    Thankyou so much for your reply
    I think I prefer the lower wave length as I have put a mercury vaper discharge UV lamp up against a 100w UV cob and they both make things glow basically the same BUT the 395nm LED cob has a lot of visible light that tends to light up the surroundings that arenít UV reactive. I think the mercury vaper discharge would be a lot lower wavelength?
    Would it work if I put more 365nm LEDs than I anticipated into my project to composite for the lower wavelength not putting out the same optical power?
    I have heard of filters but what are the best to get?
    Cheers

  4. #4

    Default Re: 365nm UV LEDs???

    i've used filters similar to these. you have to get specific ones for wavelength you're using. they will stop almost all visible light but will reduce some of the uv.
    https://www.ebay.com/i/232899453207?...8aAtGyEALw_wcB

  5. #5

    Default Re: 365nm UV LEDs???

    Quote Originally Posted by mercrazy View Post
    i've used filters similar to these. you have to get specific ones for wavelength you're using. they will stop almost all visible light but will reduce some of the uv.
    https://www.ebay.com/i/232899453207?...8aAtGyEALw_wcB
    Thankyou mercrazy I'll definitely look at it and if they do filter 99% of visible light out then could I add more leds to compensate for the little bit of 365nm loss that the filter gives???
    It's just I've seen UV lights that make things glow bright and they have next to no visible light making the effect real trippy and cool BUT I don't know

    how they have done it..... maybe what you said with the filter???

    Now if I do get the filter then I'll have to work out the size of the filter as I need one 40x15cm
    if they even come that big haha
    thankyou so much!!

  6. #6

    Default Re: 365nm UV LEDs???

    I've purchased a lot of LiteOn and Luminus 365 nm LED's for work which are used for optical inspection (probably upwards of 500 in total). They're both pretty good, but the LiteOn LED's tend to have more variation. Most produce very little visible light, however occasionally you'll get few that have a pale violet/white light. The Luminus LED's are more consistent, but also slightly more expensive.

    I haven't had much luck with using UV-A bandpass filters. They knock out some of visible light, but it wasn't a significant change. Depending on where you buy them, your results may vary.

    Check Digikey, Mouser or any of the other big name component suppliers for high quality UV LED's.

    By the way, I don't think Cree has made a UV LED in over a decade. As a matter fact, I remember reading that they bought the die's from someone else and repackaged them. Someone can correct me if I'm wrong.

  7. #7

    Default Re: 365nm UV LEDs???

    deleted

  8. #8
    Flashaholic
    Join Date
    Nov 2009
    Location
    Ottawa Ont. Canada
    Posts
    287

    Default Re: 365nm UV LEDs???

    Just curious, is there a cheap method of checking approximate wavelength of UV emitters, without resorting to expensive detectors/instruments? I was thinking of a series of patches of material which fluoresce at different wavelengths. At least the relative brightness between patches would give a idea; or would it likely be thrown off by the visible light? Dave

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •