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Fluorescence in Gel Balls

Hiemal

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Alright before you say "what" I shall explain.

A few days ago I stumbled upon a video for a scientific toy known as "water balz", basically a type of gel ball that absorbs water. Watching the video, I noticed the properties of the balls match the same exact properties of the balls inside of an air freshener I keep in my dorm (my roommate is smelly).

I took out some of the balls, and put them in a cup of water, and came back the next day to find they had swollen to about 3 times their size.

So they were the same exact thing, just as I had guessed!

So, having my lasers around I decided to play around and point some colors into it. Red and blue did nothing, but green, green caused the light inside of the ball to turn yellow...

j8ojy.jpg


Slightly better picture

mqUAy.jpg


It's kind of hard to see, since the camera was saturated. But, it was yellow as can be, something around 589 nm I think, based off of the pictures I've seen online. It was pretty neat, needless to say to see green turn to yellow! :)
 
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what kind of air freshener?! i have the next best idea. let me know what air freshener and ill post my pics on how it turned out using a special powder i have.

Thats really cool that you got a green to "fluoresce" yellow
I can clearly see that it is yellow (:
 
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Sounds like the Renewzit "Pearl Scents" air freshener my fiancée brought home a few weeks ago (had to ask her what it was called). She figured out, on a whim, a few days ago that they abosorb water and "re-inflate". I'll have to try this...
 
Nice exploration. I guess that the outcoming beam comes back to 532, in other way, you would have added a new wavelength for the laser palette.

I have done similar experiments with my lasers, and the ones producing strange colors is always the 405´s. Through thick old glasses, sometimes it changes completely the hue, but in the output turns to be 405. Curious, maybe someone here could explain us why.
 
I have seen a 405 laser turn old window glass an orange color where the beam passes through it and some plants green parts turn a kind of deep magenta color.
 
I wonder what would happen if you let the balls soaked in fluorescence water. I got some fluorescence dye from the powder set.
 
I've had green flouresce into yellow and orange colors on some bright-orange colored plastics, like the plastic clamps I sometiems use to hold stuff into place when I solder them.

It's fun :D
 
Nice exploration. I guess that the outcoming beam comes back to 532, in other way, you would have added a new wavelength for the laser palette.

I have done similar experiments with my lasers, and the ones producing strange colors is always the 405´s. Through thick old glasses, sometimes it changes completely the hue, but in the output turns to be 405. Curious, maybe someone here could explain us why.

All you're seeing within the medium that fluoresces is the 405nm photons that hit a molecule, were absorbed, then re-emitted in a random direction at a longer wavelength (490nm, for example).

Most of the 405nm beam passes through without exciting any fluorescence at all.

Trevor
 
does the GITD powder dissolve in water? I think you can see where im going here....

Not very well unfortunately, the GITD powder tends to fall out of solution pretty quickly and the particles are probably too big to be easily absorbed by sodium polyacrylate.

I wonder what would happen if you let the balls soaked in fluorescence water. I got some fluorescence dye from the powder set.

I would be interested to see what it does if it soaks up some fluorescent dye as well.

@Le Quack, if you PM me your address I can send you a vial of dye to try it out :san:
 
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Not related to the gel balls... are those some buck/boost drivers I see in the background there?:whistle:
 
This must have something to do with the index of refraction of the gel balls. If my memory serves me, the frequency of light as it passes from one medium to another is constant. However, the velocity of light and the wavelength may change.

edit: Some proof, i think. :p

λ1 = wavelength of light in one material
n1 = refraction index of the material
λ2 = wavelength of light in the other material
n2 = refraction index of the other material

formula: (n11) = (n22)

edit: ah screw this. this doesn't seem right. I tried calculating the wavelength of a 532nm laser in water and the results show 400nm but when I tried to test it the beam in the water is still green. :thinking:
 
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Not related to the gel balls... are those some buck/boost drivers I see in the background there?:whistle:

They are boards, yes. They're the new layout ones that I mentioned a while ago, but I've been rather busy the past few days to really get any made unfortunately. Got 4 types to try this time around. Rounds, mini's (adjustable and non adjustable), and micros.

Anyway, I'll PM you in a second, Addonex.

Also, Zeebit, the balls actually have the same refractive index as water, so ... yeah, that theory should be gone immediately. The only thing that makes sense in this case is Trevor's explanation. Just instead of 405 nm, it's fluorescing under 532 nm light.
 
Brightness Rating: Very High (33000)
Duration: Very Long (24+ hours)
Glow Color: Green-Yellow
Daytime Color: Very Light Green
Not compatible with water-based mediums
Grade 0, 55-85 micron
Brightest Glow Powder Sold Anywhere


Bummer. Thought it was a cool find tho. Nice informs on that subject.
 
formula: (n11) = (n22)

edit: ah screw this. this doesn't seem right. I tried calculating the wavelength of a 532nm laser in water and the results show 400nm but when I tried to test it the beam in the water is still green. :thinking:

Actually, it is the frequency of the electromagnetic wave that determines its colour. It's true that wavelength is compressed by a factor of the ratio of the two refractive indexes, but frequency remains constant. Hence, no colour change should be observed due to change in wavelength.

And when viewed from the outside, the wavelength would be back to normal anyway, since the ray has passed through the water-air boundary to reach our eyes.

Water's absorption of EM radiation is greatest for IR, hence, in the visible range, red is most readily lost.

But then again, Green - Red = Yellow doesn't make sense... Hmm... :confused:
In fact, R+G=Y...

Outsmarted by a gel ball...
 


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