Trying to help my son

[iqsavvy]

I have to help my son come up with a project at school that we will take and put together. I will be the one operating it and I am an adult. I am trying to figure out what kind of laser diode I need in order to pop a balloon. Thats all I want to do. This would totally make my sons day and being a single mom its hard to be cool so I want to do something that will get him interested and make me the cool mom. I have looked on ebay and I see all sorts of nm and mws but I don't want to get something that doesn't work and waste our time.

 

[brendon7358]

What is the due date? A good DIY laser that anyone can do would be this. Some people may suggest building a 1W 445nm but that would not be appropriate for this purpose. I suggest you pop black balloon's as they will pop the fastest with minimal effort, also try pointing the laser at the ceiling and popping the balloon rather than horizontally as you may hit someone in the eye by mistake. If you want to do more than a quick balloon pop you will need goggles for everyone watching, so I suggest pointing the laser at the ceiling then putting a balloon in front of it POP and turn it off, it is unfortunate that laser does not use a key but maybe you could take the battery out when you aren't using it. Remember black balloons for a fast pop and minimal reflection.


If you want to do everything yourself you can use this diode but remember you will also need an appropriate driver, lens, and host as well as batteries to fit the host. I am unsure whether or not the survival lasers laser comes with batteries or not but I assume it doesn't.

 

[Cyparagon]

Firstly, are you certain that "popping a balloon" meets the project criteria? It doesn't sound very scientific to me.

 

[ARG]

Do you have a soldering iron, multimeter and materials to make something yourself? You're probably looking at the 60$-80$ range for something pre-built. (without goggles)

If you are making this yourself get:

One of these diodes:
https://sites.google.com/site/dtrlpf/home/diodes/3-8mm-650nm-300mw-diode

One of these at 378mA:
Mohgasm Linear Driver - $4.99 : Mohgasm LLC, Have you experienced one lately?

One of these for the module:
Cooling Heatsink Heat Sink for 12mm Laser Diode Module | eBay

Power supply: (Batteries can be used)
AC 100 240V to 9V 1500mA Power Supply Charger Adapter Converter Adaptor US Plug | eBay

For the operator of the laser and anyone near it:
http://www.survivallaser.com/Eagle_...0nm_Laser_Safety_Goggles/p556088_5258175.aspx


You'll have to shine the laser on the balloon such that any light reflections terminate on a wall. The balloon should be held down such that it can not move and reflect the light in the wrong way. You'll also have to have a screen for the laser to terminate on after the balloon is popped.
If an accident does happen the beam will probably be diffused enough so that it does not exceed the maximum permissible exposure, but I advise against doing this at all. Bringing a laser this powerful into a classroom is a bad idea. If there is any other "experiment" you can do with your son in front of the classroom I advise you to choose the other one. There is much that can go wrong with a laser this powerful, especially with kids around.

These lasers are dangerous and are not toys. They can cause permanent eye damage.
It's still a fun thing to do with your son at home if you both have eye wear, but it's a bad idea for the classroom in my opinion.

 

[Bionic-Badger]

It's not just the laser diode that makes a functioning laser device. You also need a driver, host (heatsink), optics for focusing -- and most importantly, laser protection goggles. If you're going to assemble the laser device yourself, you need also tools to build the laser, like a soldering iron, clips for holding the parts together, and other electric circuit building parts. So if you're prepared to go through all the above, we can help you, otherwise you might as well just buy a pre-made laser and be done with it. Oh and be aware that it is quite possible that if you build a laser you'll burn it out before you even get to see it work; they're very sensitive devices, but it can be very rewarding to build your own laser.

Either way you need to have laser protection goggles for all the operators. This is something that you should not even contemplate overlooking, and could be part of the demonstration, to show that you're safety aware. Safety goggles will probably cost you about $40-$50 a pair.

For the experiment/demonstration, it should also take place in a secured, safe environment that won't have environment/eye hazards such as shiny surfaces, or objects that can burn. It's important, because these lasers can be very dangerous to peoples' eyes.

 

[RA_pierce]

Will the laser be the project or be part of the project?

Do you have the tools and skills for DIY?
Basic soldering is necessary as well as an understanding of what goes where and why.

If you don't want to go the DIY route you can find a complete laser for a low price.

A red laser (650/660nm) will be easy and inexpensive. 100mW to 200mW is plenty of power.
A green laser (532nm), however might be more impressive and fun to play with.
A 50mW green laser can pop a black balloon. It will be brighter than the red laser and safer since it is lower power.

I would recommend something like this if you do not want to solder:
Green laser module 50mW For custom build or lab [OLGLM50] - $19.00 : Zen Cart!, The Art of E-commerce
or
150mW Industrial Red laser module diode/driver built-in [OLRLMB150] - $28.00 : Zen Cart!, The Art of E-commerce
All you need to do is connect a battery and you will be good to go.

Additionally, fixing the laser in a stationary position (zip-ties, glue, clamps) and using a beam stop will ensure that risk of injury is reduced.
A beam stop can be any hard, non-reflective surface (preferably black) that will block and absorb the beam so it does not go somewhere you don't want it to.

 

[pschlosser]

I'm dubious. :thinking: