Will UV LEDs work like a UV tube?

Ahh too late to edit, I can get 385–405nm ones for super cheap, but I can see some 380nm ones for 67 cents each, woud those be better? I’m having trouble finding what the “real” wavelength one UV is.

Edit: ooh, found 100 5mm LEDs, 380–385nm wavelength, only 30 bucks! I wonder if that wavelength works well though.

hey, found this list.

http://www.riskreactor.com/Black_Lights_UV_LEDs/Black_Lights_UV_LEDs_Main.htm

seems 465nm leds are expensive, 2 for 2 bucks on ebay and I need 50 :/

hmm maye I’d get half and half, that way I could save a bit, and be able to do things that need either 380nm or 365 nm leds.

Still expensive though,

Sounds like fun ! Let us know how that works out, and which LED works best for the application.

The risk reactor site you just posted is very good. 365 nm is reasonably safe and won’t hurt you if use lower power and limit your exposure. 380–400 nm is the lower limit of human vision.
Note there are shorter wavelengths but they are not safe to use. Unless you are wearing protection, you will damage your eyes so stick with 365nm.

Don’t believe everything you see on TV. The real inspection units are shuttered and have glasses that are synchronized with the light source but at 180 degrees out of phase – closed when the light is on, open when the light is off. I won’t get into details but some fluids will glow for a short period of time (milliseconds) after being exposed to a very bright flash source of a certain wavelength. Imagine you have a bright strobe that flashes at 30 times per second and wear glasses that are synched with the flash. They close when the flash takes place and open the instant the bright flash turns off. The wearer is not blinded by the light but can see the instantaneous dim glow of the target fluid. Cool huh?
They can’t show that on TV because 1) it is too expensive, 2) the TV is strobed and you’d get nonsense. Instead, they do the easy thing and mix some UV dye into the juice so viewers see the glow and are wowed by the technology. Showmanship. It’s a bit like when they show bullets sparking when they hit metal objects. It’s nonsense but it looks neat. Actually some special effects person either put those flashes there during post processing or, in the early days, planted small charges that were detonated electrically.
Viewers don’t know the difference – or don’t care.

It’s all Physics. That is where the world’s real magic lies.

@LuckyGuy Well I’m going to order some flourescence enhancing glasses to help with showing stuff, that is, if my laser glasses for my blue laser don’t work very well.

If you are talking about the yellow plastic glasses they use for leak detection that is a good move. They block the UV that does eye damage. You are going to have fun with this stuff. When you get a chance check out a yellow higlighter pen . Look at other colors.
There is even a hair dye that glows when exposed to UV.
Have fun!

@LuckyGuy well what I want to get is some flourescing powder that mixes with water, I want to see if what they did on national treasure, putting it on the pin thing, works.

I did n ot see Nation Treasure but i have used fluorescing powder in water. In the stone age (late 60s early 70s) pilots of fighter aircraft would have a yellow pack of the stuff in their survival kit. When they hit the water they could release it and make millions of gallons of water glow so they could be spotted easily. The effect was readily reversed by releasing a bleach-like tablet.
Sometimes that material is used to test septic systems.

@LuckyGuy well in the movie he coated the pin with it, then the person who had access to a vault touched it, getting it on her hands. Then she put her password in on a keyboard, later when they were trying to get in they used a UV light to see which keys she pressed.

Does UV stuff stick around that well?

Well…. Think about it for a minute. The material would need to be selectively sticky and stay that way for a long time. You want it to come off the source object, get on the person’s hands and not come off until they touch the surface of interest. You’re talking some pretty clever chemistry.
I never say anything is impossible – unless it violates the Laws of Physics.

@LuckyGuy yeah, at least its something in the movies thats plausible though and not total BS