405 nm fluorescence in tap water

[Svenvbins]

Bought a <5mw (right) 405nm pointer from dealextreme for just a couple of bucks, so I'd have some kind of pointer other than my projector. Measured it at the lab this week and shows about 60mW, 40mW with the diffraction gratings.

Now, I've heard you can use 405 to get beams in tonic - it's got something that fluoresces. However, it seems my tapwater does that just as well! So I'm wondering, what's in the tonic / tap water that fluoresces?

I'm guessing some minerals in the tonic & water, and some bacteria in the water?

 

[USAbro]

I don't see it flouresing.

 

[Svenvbins]

The blue beam in the water is fluorescence. It's clear tap water, the red beam goes through without showing the beam and it's also clearly a more greenish color (longer wavelength) than the 405.

Edit: I wrote "The red beam goes through". That's when using a red laser, anyone who's still looking for the red laser in the picture can take a break!

 

[USAbro]

The blue beam in the water is fluorescence. It's clear tap water, the red beam goes through without showing the beam and it's also clearly a more greenish color (longer wavelength) than the 405.

Edit: I wrote "The red beam goes through". That's when using a red laser, anyone who's still looking for the red laser in the picture can take a break!

Wow that's odd. My 450nm does the same in my fish tank. Although the 405 does better. I know what you mean though. I own a 380nm flashlight and water shows flouresing that way too.

 

[Svenvbins]

I'll just quote Cyparagon's post here:

Quinine - Wikipedia, the free encyclopedia (Quinine - Wikipedia, the free encyclopedia)

He deleted it because he apparently didn't read my question close enough ( ) But I think the answer is useful anyway, because I also didn't know what was the fluorophore in tonic. So, thanks!

Yesterday I also noticed that I have many red fluorescing spots on my face! A bit difficult to make out, but I think it's (near) the hair follicles. Looks really weird! And of course the small whiteheads also show really well ^^

 

[USAbro]

About whiteheads anything white shows up under high frequency light. Between like 345-410nm.

Also what was flourescing?

 

[sky]

so many useful threads,thanks

 

[hakzaw1]

Pretty much all liquids show the beam --but tonic is much brighter-- I always thought it was the gin!!lol

To see what actual flourescing looks like put a highlighter 'wick' into a small bottle of water any color works - and you will see how much brighter that is compared to tap water..

you can buy invisible ink that only can be seen with 405 or a blacklight- its used in clubs to stamp your hand.. we used that one on those under 21-- and a visible stamp on the rest-- that way my bartenders can see the stamp and with a handheld battery blacklight we(or any bouncer/doorman) can see the stamps on the hands of the minors--