Blue balloons resistant against blue laser

[Stadsjaap]

Hi,

I've been doing some experiments with range popping of balloons with a 1000mW 450nm blue and I've found blue balloons to be highly resistant, even at close range. This has been consistent, too. One of them took 37 SECONDS to pop!

Does this hold for lasers of different colous (ie, red balloons resistant to red lasers, green to green and so on)?

I also notice that the whole balloon glows bright blue when the laser is aimed at it. Different coloured balloons go almost instantaneously, so I can't be sure if they yield the same glow without some serious slow-mo. But I'm willing to bet they don't.

Does anyone know how the physics behind this resistance works? Can a layer that thin really provide enough scatter to last 37 seconds?

Still, awesome trick with people who don't know anything about lasers:

(SAFETY NOTE: The laser should be well mounted on a mic stand for this, or people might drop it or point it somewhere unintended!)

1) Show your audience with a same-coloured balloon until it eventually pops (yawn!).
2) Swap the balloon out for another colour and let them have a go at turning the laser on.
3) Laugh your butt off when the balloon pops as soon as they touch the on switch ]:-}

 

[Blord]

You are doing something wrong.

A 180mW blue laser popping balloons in seconds. I am sure a 1000mW 445nm blue will pop any balloons instantly. You must focus the dot into a point at the balloon.

 

[Stadsjaap]

It does. It pops all other cloured balloons instantly and lights my smoke if my Zippo quits.

Youtube "Balloon death row - custom 1100mw blue laser." I'm not the only one...

 

[Stadsjaap]

Sorry, here's the link:

http://www.youtube.com/watch?v=RVBzhPZwaD0

 

[justinjja]

A balloon that appears blue to your eyes, appears blue because it reflects blue light into your eyes, while absorbing other colors,
makes sense to me...

 

[piferal]

Speaking of the visible spectrum of the light, what is certain is that if the balloon (in this case) has the same color (wavelength)
as the laser beam, the balloon will take longer to explode, or will not explode.

Of course, and speaking of a simple balloon, if we use a powerful laser, well focused, and a short distance, you may not see much
difference between one or another color (but there is).

When you use the same color balloon-laser beam, following happens, the balloon (or other objects) is blue (or other color) because
it is the light (or predominant) light (wavelength(s)) reflected, and for this reason is perceived by our eyes as color blue, or other.

That means that if the balloon is blue and the laser beam has the same color, a very important part of this wavelength will be reflected out,
and that is why it is, something, more difficult, or not possible explode the balloon.

The same "or similar" with the other colors.

That's why balloons with "black color" explode very easily, because absorbs all visible wavelengths, with white, very light colors,
and with the same color of the laser beam, is the opposite.

 

[Stadsjaap]

Thanks, that makes sense.

I'll time with some different colours at different distances and report back.

 

[piferal]

Apart from black or very dark colors, "generally" work very well the complementary colors, that is, if for example
we have a blue laser, to explode up a balloon get its complementary color, ie orange.

Try it and see what happens.

 

[Blord]

In fact any non-blue balloons pop faster than a blue balloon with a blue laser. But against the power of Mordor there can be no victory, oeps I mean 1+ Watt lasers pop any color instantly.

@Piferal : Good explanation about the colors.

 

[Lethere Belight]

So if the military develops a laser to shoot down planes or missles, all the enemy has to do is make their missles and planes the same color as the laser.

 

[Blord]

So if the military develops a laser to shoot down planes or missles, all the enemy has to do is make their missles and planes the same color as the laser.

That doesn't work. What color has a CO2 laser ?
The military lasers shoot thru everything, even polish metal I think.

 

[piferal]

So if the military develops a laser to shoot down planes or missles, all the enemy has to do is make their missles and planes the same color as the laser.

Hahaha, I guess it's a joke, right?

Already exists various military laser weapon, and the colors have nothing to do here because
is a very high power lasers, and also those laser working in a diferent wavelength, normally IR.

Here one example.

 

[Lethere Belight]

Hahaha, I guess it's a joke, right?

Already exists various military laser weapon, and the colors have nothing to do here because
is a very high power lasers, and also those laser working in a diferent wavelength, normally IR.

Here one example.

Yes it was a joke. You just need to make the planes invisable.

 

[Stadsjaap]

@Blord: I guess mine isn't as 1000mW as it makes out to be. (A proper 1000mW should be able to ignite steel wool at point blank range, right?)
It actually gives only one "rating" on the device itself, but I won't repeat it here for fear of making my name ass.

 

[nouthyella]

Most high power blues are in fact 1w lasers, since there are few diodes at the price point of ~$50 which can output blue, with the exclusion of the single mode 445 Osram which costs more than the C@$io diode used in virtually all 445nm lasers.
You just need to focus the point. A 1w 445 can indeed make steel wool glow and instantly pop balloons, even blue or transparent ones. When properly focused, it could melt through a transparent PET bottle if focused on an imperfection in the plastic.

 

[Stadsjaap]

Grrr, I'm having trouble with purple balloons too!
So, I pointed the laser at the very top of the balloon where the material is at its thickest and something interesting happened... It quickly burnt a tiny hole, but cauterized the tear, causing the balloon to deflate gradually rather than pop. Bizarre.

@nouthyella: where do I start looking for focusing lenses? And please tell me they're all a standard size ]:-}

My laser is a serious no name brand, which may make fitting lenses easier... or a lot more difficult!