Random request: Help calculate the minimum power density needed to pop a black balloon

[CurtisOliver]

As the thread title suggests,
I am asking for those with a bit of spare time on their hands to help me out with a fun little problem.
I'm not going to give away the reason why yet, but I appreciate it is a random request.
These are the conditions:

1. The laser/s used must be LPM'd
2. The laser must not be focused in any way
3. The dot size must be accurately determined on both axes.
4. The balloon must be black.

I will then do the calculations myself.
Thank you.

It's probably best that you avoid testing with high power Class 3b's/4's. Stick to <100mW.

 

[Anthony P]

Instantly pop? or over some seconds?

 

[CurtisOliver]

I’d say maximum 3-4 seconds. Doesn’t necessarily have to be instant. I’ve basically got to simulate a much more powerful laser over a large distance.

 

[paul1598419]

Are you looking for the least power that will pop a balloon? I don't see what you are trying to do here.

 

[Anthony P]

I have a CO2 laser that I can vary output power and meter. Also expand beam and measure diameter to calc power density. Just need to find some black balloons. Let me know if you think this could help.

 

[CurtisOliver]

Are you looking for the least power that will pop a balloon? I don't see what you are trying to do here.

Paul, specifically I am looking for the least power density to pop a black ballon. Because power alone isn’t enough to know on it’s own. If I can work out the rough W/cm2 required, then I can calculate how far away I can pop the balloon with a Class 4 with known beam specs.

I have a CO2 laser that I can vary output power and meter. Also expand beam and measure diameter to calc power density. Just need to find some black balloons. Let me know if you think this could help.

Shame it’s a CO2 as your setup would of been perfect. Ideally it has to be a visible wavelength as the absorption will differ at that part of the spectrum. I’m not sure how much the absorption changes with something like a black balloon however. Probably not much that can be found out with a trivial object like that.
Thanks a lot anyway.

 

[Seoul_lasers]

hmm, not a very scientific study. You've got to get more control of your variables. --- What wavelengths at what powers?
Maybe listing 20 wavelengths of lasers from NIR to NUV and then show results over a range of power levels might yield better results? Documenting the testing conditions will also be equally as important.

 

[Alaskan]

This may be of interest to others following this thread:

What is the minimum power needed too....

Pop a dark colored balloon? Pop any balloon? See the beam at night? See the beam during daylight? Melt electric tape? Light a match? Blind someone? ...with a green laser pointer? I just think this could be a handy reference, especially for those of us who would like to know the power of...

www.candlepowerforums.com

Edit: I just noticed this is an old thread...

 

[Lifetime17]

HI,

Rich

 

[CurtisOliver]

Thanks for replying Seoul. This thread is old and I have partially solved it through experimenting and calculating. I used a 4.25W 532nm at a set distance and measured the beam spot and calculated the intensity. I then used a temporal cut off due to the application of which I was needing it for. I haven’t got the results on hand at this moment.