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IR laser deflourescenating?

randomlugia

randomlugia

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Hey, I found something really weird today. I was lighting up a glow in the dark star with a flashlight, and I thought it would be cool if my ~10mW IR laser could make it glow (my 650nm could). So I pointed it at the still-glowing star, and it acually made it stop glowing! The laser dot also turned dark red (usually invisible). It's like the oposite of a BR- you can draw on stuff that's already glowing. Mabye because it's on the opposite side of the spectrum? Anyway, it's just barely visible. Has anyone tried this with a powerful IR laser?
 





Xplorer877

Xplorer877

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Sounds to me like you're right the IR light does have an adverse effect on how long a glow in the dark item holds its glow. :p
 
Switch

Switch

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I noticed this with my red.It needs way more power and exposure to discharge still slower than it gets charged with BR, but for sure it happens.For example if I leave it on for like 5 seconds on the same spot, the spot almost completely discharges, can't really "draw" but it does happen.If only 10mW of IR does this, maybe deeper IR will have a better effect. :D
 
Crossfire

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I'll need to try this with a GITD cap and my 1100mW 808nm laser. I'll charge it up with some blu-ray then discharge.
 
Switch

Switch

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Crossfire said:
I'll need to try this with a GITD cap and my 1100mW 808nm laser.  I'll charge it up with some blu-ray then discharge.
Click to expand...
Well go for it! ::)
 
Benm

Benm

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This effect is quite wellknown. Phosphorescense (which is what actually happens in gtid materials) thanks is long lasting effect to a forbidden electronic transition - this results in electrons remaining at a higher energy level for a long time.

Shining light onto such materials will actually aid in removing electrons from this higher energy state, 'discharging' the gtid material. It should be possible to do this with a red laser as well, but the effect might not be so apparant because the red light overwhelms your vision.
 
Switch

Switch

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But it's definatly wavelenght dependant.I wonder where the peak is. :D
 
randomlugia

randomlugia

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Acually my red charges it if held long enough.  I think it's in the higher IR wavelengths. I tried it with my night vision camera, and the second I placed the star over the night vision light, a spot in the middle instantly went dark in the shape of the light. :D
 
Benm

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Switch said:
But it's definatly wavelenght dependant.I wonder where the peak is.  :D
Click to expand...

The most effective wavelength to discharge a gtid material would be whatever the material emits. If you have ones that glow a green-cyan color, a 532 nm laser might be very effective.

IR can be effective too sometimes, resulting in decay from the charged state through a route that is normally present too, but invisible because it's IR.
 
Crossfire

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I charged up a GITD cap with quality UV from a fluorescent blacklight then irradiated it with my 1.1W 808nm laser. I didn't notice any appreciable dimming other than the normal decay in darkness.
 
billg519

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Maybe the effect described is unique to the material? I just lit up a piece of gitd plastic with a bluray, and then ran my 2w 808nm over it. I didn't detect any effect on the glow. My 4w 960 nm also had no effect. Did the experiment in darkness to make sure I would notice any effect.
 
Schrecken_Licht

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That's funny....I noticed that effect a few nights ago with a piece of GITD plastic (typical greenish-glow) - I hit it "point blank" with my 173mw 660 red, and where the beam hit it pretty much killed all the glow. I had always thought light of any color would charge up GITD stuff, but apparently not. I have some GITD paint around that glows orange, I'll have to try my red with that and see what it does.
 
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