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FrozenGate by Avery

Green laser spot being orange on orange surface

KabaT

KabaT

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I have recently bought a cheap green laser pointer. It's power I assume is much greater than 5mW it should have but I didn't measure it yet. Today I noticed that when I shine it on the kind of orange plastic scrap the dot changes itself into orange one. Same happens with red/pink one. But on the same kind of plastic scraps colored blue, green and yellow the dot seems to be the same kind of green as on other surfaces.
I have heard about 405nm lasers that they produce this kind of effect on various surfaces, but never heard of green behaving like that.
Could someone explain me why this happens?
I can also provide a video if needed.
 





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This happens with all green lasers :)
 
But only on orange like surfaces? And why is that happening? I mean on the molecular level?

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So I read some wikipedia articles on that subject.
I read that the wavelength of fluorescence is longer than the light's shining on object so I think I get it why only reddish ones do that.
But there they say that things fluorescence when under the ultraviolet radiation what I knew before but I never heard about the case of green one.
 
It's the same thing. Wikipedia is world editable and often edited by people with limited knowledge.

This has been observed in quite a few different materials and wavelengths and I have been meaning to
do a video on the subject. "Hot colored" materials and dyes often use this trick to make an article
appear unusually bright by actively stokes shifting higher wavelengths instead of merely selectively
reflecting incident light. It doesn't matter what the wavelength of the incoming light is, as long as it is
high enough to cause excitation.
 
Simply , the orange material is absorbing the 532nm photons , then re emitting it at a lower energy photons ( its fluorescing ) ( orange in this case )

I have yellow plastic this will emit a strong green/yellow light when it absorbs 473nm ( blue ) light .
 
Not only DPSS, even the 520nm green diode laser will have the same effect on fluorescent plastic even the laser dyes in the range from 560nm yellow to 680nm red. As such, there is NO infrared light of any kind from the green laser diode, if you are curious.

Fluorescence is also what makes Glow In The Dark plastic lit - green laser may excite it or kill the fluorescence action, not sure as it have been a while since I have had any GITD piece but if you have purple (Blu-ray Disc) diode laser and the GITD plastic piece, you would also observe the same (or similar) effects as you would with green laser and fluorescent orange plastic.

*** EDIT: Being said, it doesn't have to just be plastic, wherever the fluorescent dyes are, the better chance you would be able to light it up - fluorescent orange towel would do fine, BTW. Fluorescent orange plastic (perspex) tend to light up intensely when lit by either green or UV laser for some reason - slightly higher doping percentage of the dyes (6 - 10 % per oz) used therein may be the reason.
 
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I dont think this is fluorescent behaviour just reflective properties of the plastic taking IR photons and emitting lower energy orangeish red photons out and the plastic heats up in return as excess energy is produced. In study physics and it seems more likely to me judging by pictures I see.

Also what I described is a possibly definition for fluorescent action btw... edit

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xirrious said:
I dont think this is fluorescent behaviour just reflective properties of the plastic taking IR photons and emitting lower energy orangeish red photons out and the plastic heats up in return as excess energy is produced. In study physics and it seems more likely to me judging by pictures I see.

Also what I described is a possibly definition for fluorescent action btw... edit

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Click to expand...

It is flourescence. IR photons have lower energy than red photons. Flourescense can be demonstrated using green emitting led. Obviousely green leds do not emit any amount of thermal radiation to heat a material.
 
Didn't know it worked with leds guess your correct like I said what I described could be considered fluorescence .. or maybe its black body radiation I was describing? Eh who cares
 
HUH?! Infrared converted to red light by fluorescence? Cannot compute. Cannot compute.

It would break optical physics unless you mix several IR wavelengths (or halve it) of several tens / hundreds of milliwatts power through nonlinear optical crystal then you can get red light or any color as long as it is the sum of wavelength.

Fluorescence is much cheaper to obtain multiple longer wavelength light - like ultraviolet source light = resultant visible to infrared light. So infrared is definitely NOT involved in "Ooh, bright orange light!" that you get with green laser pointer and fluorescent orange plastic. Try that with 520nm green or 450nm blue Gallium Nitride LED, it couldn't be clearer.
 
I am aware of the Anti-Stokes infrared detector cards (I have used them before), however this post was somewhat about Stokes process with green light, and not everything exhibits anti-stokes process (like most fluorescent plastics). And, as an interesting matter of fact, Anti-stokes IR detectors definitely will light up with 520nm green laser light from the diode (if you want to be sure there's no infrared light) or even purple (405nm) laser.
 
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