XBox BluRay Balloon pop

[flogged]

Just had to do it. Here are a couple videos of my just completed xbox bluray pointer popping a couple balloons at 6+ feet. I'm driving the diode at 82.5mA, which should put the output over 50mW. There's some tang there.

More on the pointer, here:
http://www.laserpointerforums.com/forums/YaBB.pl?num=1209940381/348#348

[media]http://www.youtube.com/watch?v=rfQJaTckSYs[/media]

[media]http://www.youtube.com/watch?v=l2W_DHgZi30[/media]

 

[360freak]

Awesome. My DIY materials should be arriving soon, and my vids will be up too once completed. Can you post your parts?

 

[Glaserfan]

I managed 12 feet with mine.. it's all in getting the lens clean and focused.


Although I did notice that 405nm does a much better job at burning in general then 650nm.. I can only imagine what these wil do once they hit 200mw or so

 

[flogged]

Awesome. My DIY materials should be arriving soon, and my vids will be up too once completed. Can you post your parts?

Parts? For the driver I'm using the simple but effective 'DDL' circuit. More than you want to know, here:
http://www.laserpointerforums.com/forums/YaBB.pl?num=1185701612

I got all the electronic parts: LM317T voltage regulator, 47uF electrolytic capacitor, 2 10 ohm resistors, 25 ohm rheostat, and a IN4001 silicon diode.. at radioshack. This includes the box and battery holders,. SPST toggle switch.

I'm using the Meredith LDC-2 lens assembly and heatsink. Look here:
http://www.mi-lasers.com/cgi-bin/shopper.cgi?search=action&keywords=diode_optics

Then combine elbow grease, solder and glue to finish

If you're going to make one of these you need to have a DMM, IMO. Since each diode is unique (along with variances in all the parts) you need to be able to adjust the current, this also allows you to control the brightness of the diode. Hence I use a variant of the DDL circuit with a trim pot (the 25 ohm rheostat) to make this easy to adjust.

 

[flogged]

I managed 12 feet with mine.. it's all in getting the lens clean and focused.


Although I did notice that 405nm does a much better job at burning in general then 650nm.. I can only imagine what these wil do once they hit 200mw or so

Heh, I haven't attempted any distance records yet with mine. Beyond a certain power level the optics become more important for getting a good focus. For example, one of my best burners was 'only' a 120mW red. I had the diode perfectly centered in a fast Meredith acrylic lens assembly which yields a very tight focus. That rig would kill balloons at over 50 feet in less than 5 seconds.

I've got an unused Meredith glass lens I need to figure out a way to get the coatings off - this may yield a 20% increase in power. Unfortunately, outside of a pro optics lab, I know of know easy way to get the AR coating off a glass lens w/out resorting to powerful acids (like hydrofluoric acid) which also damage the glass.

 

[Glaserfan]

My other hobby is projectors..I know once I screwed up bu using a cheap glass cleaner(high ammonia content) and screwed up the AR coating on my lenses.. I wonder if that idea could be put to productive use here?

 

[flogged]

I don't know anything about getting the coatings off. I was aware the lens coatings were for a red laser (~ 650 nm) - I just wasn't aware they attenuated so much of the 405nm light. Ideally somebody will find a supply of quality glass lenses with coatings meant to work at 405nm. That would be ideal. The coatings optimized for 650nm turn out to be rather opaque at 405nm

Wanted to add, I think there are a few reasons 405nm is more effective for burning that 650nm. The higher frequency allows for a smaller spot size at focus. Just one of those physical laws. Also, those high energy violet photons may be better absorbed by some materials.