"Black" LEDs

[ExpAnonColin]

Do you think it would be better to go with purple LEDs?  That's generally perceived as the darkest color, no?  And do they make blacklight bulbs in 5mm size?



-Colin

[Ansil]

they make blacklight leds
chekc out bettycats page for a link

[idlefaction]

heh, i don't speak german and couln't find a link for any blacklight LEDs - but i liked bettycat's tele collection!

i did find a UV LED on mouser.com tho, i just searched for 'ultraviolet LED'.

[Peter Snowberg]

If you want less brightness, just use a larger dropping resistor. I wouldn't install UV LEDs in anything intended for looking at. UV is damaging. Some sources actually require you to sign a waiver in order to purchase. There are some near-UV or deep purple LEDs that I do like the color of, but then there are also LEDs that put out UV-A. You can stare at a UV source and go blind without realizing it.

Just because it doesn't look bright doesn't mean that it's not bright.

Take care,
-Peter

[ExpAnonColin]

Ansil-what's bettycat's site?  Can you direct link me to the blacklight LEDs?

Idlefaction-there's TONS of UV's on ebay.

Peter-I don't want less brightness, I want really bright black LEDs.  Plus, you couldn't create black by using more resistance.

-Colin

[Ansil]

heh, i don't speak german and couln't find a link for any blacklight LEDs - but i liked bettycat's tele collection!

i did find a UV LED on mouser.com tho, i just searched for 'ultraviolet LED'.

http://www.blauetachos.de/

thats from her site.  but its still in deutsch
sorry i am germanic in descent

[Ansil]

you can select english.. and then click on the shop link i din't see the black lights but ith oguht iwas her site i saw someone talkin about them i could be wrong.

they have white green blue pink violet red yellow orange

[ExpAnonColin]

heh, i don't speak german and couln't find a link for any blacklight LEDs - but i liked bettycat's tele collection!

i did find a UV LED on mouser.com tho, i just searched for 'ultraviolet LED'.

http://www.blauetachos.de/

thats from her site.  but its still in deutsch
sorry i am germanic in descent

You can select english, and I see no such black LEDs

-Colin

[Peter Snowberg]

Peter-I don't want less brightness, I want really bright black LEDs.  Plus, you couldn't create black by using more resistance.

-Colin

:?

Black is the absence of light in the visible spectrum. You can't create black with any light emitting anything. It's an oxymoron worse than airline food (airline 'food' is at least caloric).

I'm having trouble understanding what you're looking for.

-Peter

[Ansil]

colin there is a blacklight xenon type strobe bulb that i have seen before i think ratshak had them at one time. but that ahs been years ago.

[Peter Snowberg]

If by chance you're looking for something to illuminate fluorescent pigments, all you need is a wavelength that's shorter than the dye you want to make fluoresce. Blue LEDs do this surprisingly well.

If you have a theatrical supply house near you, ask them for a swatch book of gels. Gels are filters made of either polyester or acetate for coloring stage lighting. There are larger books that they sell, but they should also have giveaways with pieces about 1 inch by 3 inches in all the colors they make. The three largest produces are Roscoe, Lee, and GAM (Great American Market).

if you want UV LEDs, try http://www.superbrightleds.com

Take care,
-Peter

[ian87]

thats from her site.  but its still in deutsch
sorry i am germanic in descent

just for the record, "bettycat" AKA Dirk, is a man.

[ExpAnonColin]

:?

Black is the absence of light in the visible spectrum. You can't create black with any light emitting anything. It's an oxymoron worse than airline food (airline 'food' is at least caloric).

I'm having trouble understanding what you're looking for.

-Peter

Black light-you know the trippy effect they used a lot in the 80s, where the lights were actually sort of purple, and they made white glow... black light, you know?

I have a source for UV LEDs, my question was, how "dark" (not not-bright dark, but black light dark) will these be?

-Colin

[ExpAnonColin]

colin there is a blacklight xenon type strobe bulb that i have seen before i think ratshak had them at one time. but that ahs been years ago.

Hmm... A small, blacklight bulb, you mean?  I'm not sure if I understand.

-Colin

[ExpAnonColin]

10pcs 5mm Ultra Bright 8000mcd U.V. Blacklight LEDs
Features:
Super Luminosity U.V. LED
InGaN / Sapphire chip
Standard T1 ¾ LED
I.C. Compatible
Low Power Consumption
Long lasting (>100,000hrs)
Detects forged bank notes
Water Clear Package
10 FREE Resistors    Specification:
Emitting Color: Purple (U.V.)
Peak wavelength: 395nm
Luminosity: 6000-10000mcd @ 20mA
Viewing Angles: ±15 degrees
DC Forward Current: 30mA max
DC Forward Voltage: 3.3V typical
Reverse Voltage: 5V max
Soldering Temp.: 260 °C for 5 secs   
In Stock
YES
   
£5.95 (10 pcs)


Score!  Too bad it's in england.  I knew that blacklight had to be UV, or at least produceable by it.

-Colin

[Kilby]

I have a few UV LEDs.

Basically they are a very bright blueish white from the ones I used http://www.maplin.co.uk/products/module.asp?CartID=031128125002188&moduleno=33371&Products=1 to me anyway.

They are pretty damn cool looking though.

If you are gonna use it on something desktop based, then I suggest not bothering, as previously said it's visible band bright, and it's UV componant is probably brighter (but only insect life can see it).

If it's a floor based box it will probably be OK as I doubt it is giving off that much UV. Though you could mount it inside and use something with facets to desperse the light.

This would is particurlarly cool if the substance is UV reactive which was what I was going to do, as most of the UV is absorbed then discharged as visable light it should be safer to use.

If you want it to wash across the top of your pedal to show up UV ink or something then use a light pipe.

Rob...

[BillyJ]

OK I was keeping this to myself but really I have no reason to so here is an idea I had.
If they can be found or made think of a little semi circle half dome...more like a quarter slice of a ball...or kinda like those fancy ampitheaters where classical music comes to mind...
Ok anyway find these little buggers that will fit over the UV LEDs get yourself some day glo paint and if the light refratcs well enough you could have control lettering and such just beam out at you without getting an eyefull of UV.
Probably still not the best idea in the world but better than having the UV pointing out where it could do some harm.
I have a couple and I have seen the warning sticker that came with them..I won't be looking at one ever!
Anyway there is my super original idea.
Now if anyone ever comes across those little domes deal I'd love to get some.

[j.everman]

You might try www.hosfelt.com, I think I saw some UV black or purple LED's there once.

[Peter Snowberg]

Black light-you know the trippy effect they used a lot in the 80s, where the lights were actually sort of purple, and they made white glow... black light, you know?

I have a source for UV LEDs, my question was, how "dark" (not not-bright dark, but black light dark) will these be?

-Colin

Ah man... the 80s? Now I'm starting to feel old!  :lol:  I remember it a bunch in the early 70s   I know it predates me by a long while too.

If you can get a super bright blue which are cheap & efficient and combine that with the gel filters I mentioned above, you can knock out most of the blue frequencies can leave only the upper end. When you do that, they take on a 'dark' shade of purple just like fluorescent "black lights". The light is still visible BUT enough comes through to easily trigger green-yellow fluorescence, as well as anything of longer frequency (going towards red), plus, it's not harmful to the eyes the way point source UV lamps are. When blue light hits yellow orange or red fluorescent materials, the fluorescence will generally be bright enough that your eye's greater sensitivity to the green-yellow to red area of the spectrum to make the fluorescence jump out and the blue isn't noticed as much.

If you use a UV LED, be sure you don't allow it to be viewed directly. It should pointed down, away from eyes. If you have something backlit, it should filter blues out quite well so you may be able to use a blue LED by itself and it should glow brightly.

Try walking around your house with a blue LED running at 25mA and see what glows.

Try getting some fluorescent dye like a stamp-pad re-inker refill, add the dye to de-ionized water to taste, and add a little "pearlescent" soap. Put that mixture into a glass container on the effect, and backlight or sidelight it with blue LEDs. I have a feeling you'll like it.

Take care,
-Peter

[ExpAnonColin]

Thanks everyone for the tips.  I think the gel is too much of a hassle.  If I was to get UV LEDs, I'd without a doubt get them on eBay.

I'll probably just use red LEDs... how boooring.  That way I can avoid destroying my eyes at such a ripe age.  

-Colin