# Playing with blu-ray laser pointer



## PhotonWrangler (Jul 22, 2011)

Out of curiosity I aimed my blu-ray pointer at a CRT tv set and it caused a bright greenish-blue glow. Inspecting the glowing phosphors up close I found that the blu-ray wavelength produces a strong fluorescent response in the CRT's green phosphors, a moderate response in the blue phosphors and no response at all in the red phosphors.

I've also found that it creates a striking but brief reddish-orange phosphorescent (after-glow) response in a rock that I have yet to identify.

If you have one of these violet laser pointers, aim it at some rocks and see if you get a response.

Yeah, I'm easily amused.


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## norman$ (Jul 23, 2011)

PhotonWrangler said:


> I've also found that it creates a striking but brief reddish-orange phosphorescent (after-glow) response in a rock that I have yet to identify.
> 
> If you have one of these violet laser pointers, aim it at some rocks and see if you get a response.


 
I've also used one of these guys for gemological purposes- stones having chromium as a chromophore fluoresce nicely.


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## bshanahan14rulz (Jul 25, 2011)

Try peanut butter


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## PhotonWrangler (Jul 25, 2011)

bshanahan14rulz said:


> Try peanut butter


 
I don't have any PB in the house. What does it do?


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## bshanahan14rulz (Jul 26, 2011)

It glows for about a half second after exposure. I also have some switchplates (like, on wall switches for the lights) that glow for some reason, although they weren't designed to do so. Also, if you have any glow-in-the-dark items, 405nm will charge it up nice and fast.


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## PhotonWrangler (Jul 26, 2011)

Wow, so peanut butter has a phosphorescent compound! I'm going to have to try that sometime. It seems that a blu-ray laser can charge things up more aggressively than a regular fluorescent blacklight bulb, and thus it tends to reveal some weaker sources of phosphorescence. It opens up a whole new range of materials to test with it. 
:huh:

Of course this raises the big question: chunky or creamy?


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## bshanahan14rulz (Jul 27, 2011)

I personally tried it on some creamy, but I can't imagine chunky being that much different. Get whatever kind you like best!

Also, if you can ever find them, I use yellow-lensed goggles to block 405nm and 445nm, they are great for picking up fluorescence because you don't see the 405nm, but you do see whatever wavelengths it gets converted to.


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## PhotonWrangler (Jul 27, 2011)

Just tried it on a peanut butter energy bar. No phosphorescence but I noted a whitish fluorescence.


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## FRITZHID (Oct 11, 2011)

PhotonWrangler said:


> Out of curiosity I aimed my blu-ray pointer at a CRT tv set and it caused a bright greenish-blue glow. Inspecting the glowing phosphors up close I found that the blu-ray wavelength produces a strong fluorescent response in the CRT's green phosphors, a moderate response in the blue phosphors and no response at all in the red phosphors.
> 
> I've also found that it creates a striking but brief reddish-orange phosphorescent (after-glow) response in a rock that I have yet to identify.
> 
> ...



yeah, i know, beatn a dead horse on a dead thread,,,,, BUT i have quit a bit of exp w/ the so called "blacklight" or UV lasers.... try scoping out some diamonds art a low end jewelry store and have some fun, letting them know, if they don't fluoresces, they are ether cheap or fake even! lmao. i always bring mine when diamond shopping!  i also use it for picking out the best in GITD materials, weather or not teeth are clean, and they do a great job at finding that small lost thing on the floor (IF it fluoresces.) they do well on the GITD Cryaola boards, and i often use it to charge any other GITD items before i leave home.


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## bshanahan14rulz (Oct 11, 2011)

I believe that the amount of fluorescense in a diamond isn't in itself an indication of fake vs. real, but more an indication of purity. Natural diamonds will vary much more than lab ones. Of course, I'm sure high-end stores would use that as one of the criteria for picking cleaner, more pure diamonds. You don't want diamonds fluorescing cloudy blue on a sunny day...


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## FRITZHID (Oct 17, 2011)

bshanahan14rulz said:


> I believe that the amount of fluorescense in a diamond isn't in itself an indication of fake vs. real, but more an indication of purity. Natural diamonds will vary much more than lab ones. Of course, I'm sure high-end stores would use that as one of the criteria for picking cleaner, more pure diamonds. You don't want diamonds fluorescing cloudy blue on a sunny day...



to an extent this is true, but also look at the Hope Diamond.... when exposed to UV for a few mins, it then glows a deep red/maroon color for a short time in the dark afterward.... and it's the most valuable diamond to date.


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## Longwinters (Nov 13, 2011)

Isn't that because of it's size?


FRITZHID said:


> to an extent this is true, but also look at the Hope Diamond.... when exposed to UV for a few mins, it then glows a deep red/maroon color for a short time in the dark afterward.... and it's the most valuable diamond to date.


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## MikeAusC (Nov 13, 2011)

I shone UV on green Pistachio nuts - they fluoresce Red - no afterglow.


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## FRITZHID (Nov 13, 2011)

Longwinters said:


> Isn't that because of it's size?


the glow, or the value?


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## xxcat (Nov 16, 2011)

any photos would be good~~~:naughty:


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## bshanahan14rulz (Nov 17, 2011)

I thought the hope diamond was natural?


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## FRITZHID (Nov 17, 2011)

bshanahan14rulz said:


> I thought the hope diamond was natural?



ya, it is


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## jspeybro (Nov 21, 2011)

MikeAusC said:


> I shone UV on green Pistachio nuts - they fluoresce Red - no afterglow.


fluorescence is an effect that happens on a nanosecond scale which we percieve as instantanious since our eyes have a rather slow reaction time (quarter of a second), while phosorescence happens much slower so it can be percieved as an afterglow depending on the material and is often less intense.

many food products (like nuts) show natural fluorescence but little show a phosphorescence effect.


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## bshanahan14rulz (Nov 22, 2011)

red postage ink is fluorescent, and those colored stickers that you sometimes find on boxes after you ship them, those are too. Some of my lightswitch covers in my apartment are phosphorescent, although not by design.


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## richard william (Nov 25, 2011)

where can i buy a blu ray pointer from?


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## FRITZHID (Nov 25, 2011)

richard william said:


> where can i buy a blu ray pointer from?



ebay has 100's of them, just search UV, purple or blacklight laser pointer


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## reehasmith (Dec 14, 2011)

I never use these laser pointers and i also recommened every to take care of others while playing with them because mostly kids disturbs us with these lasers pointers.


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## bshanahan14rulz (Dec 14, 2011)

The danger with wavelengths like 405nm is that they are so hard for the human eye to detect that we see it as a feint dot when really it is much more powerful than it looks. 5mW of 405nm is quite dim-looking. Compare it to 5mW of 532nm radiation, which is blinding to look at the dot.


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