Making a laser more powerfull

So I got myself a nice 50mW, im happy but now I want to do some stuff with it and I see vids of people on youtube who hold smalls lens infront of their laser even as low as 40mW and get it to burn stuff.


Im not looking for some kind of laser spreader to make my laser look like star wars lightsaber but something that will consentrate it and will produce more heat to melt stuff. Would something like a loup to magnifie stuff work? Or I heard that you should buy a cheep dolar store laser and cut it off at the sticker and take its lens and hold it over your laser when you shoot it. I have also tried binuculars and they dont work....

Any help please!

I've used small magnifying glass helps lasers burn someone told me a disposable camera has some nice lenses inside that are useable

I just found one of my old cheep 1$ lasers and took all the crap out of it and finaly got the lens, it spreads the beam out if you got past 3 feet but before that it makes it realy consentrate and my 50mW can now burst ballons in like 2 seconds insted of 10, NO POT MOD. ;D

Im just going to clean it up and install it on a tooth paste cap and then its going to be nice.

xJ --

Be careful of your eyes. You are probably getting your nose right down there to focus that lens. If you get close, use goggles.

Mike

Problem is that my goggles are to bulky and I cant see well through theme so I keep missing when trying to focus the lens, but as long as I keep clear of the beam and it does not reflect off stuff I should be just fine. I can now light a match with a 50mW Green Laser and as I said NO pot mod or resistors modified and no IR filter removed.

Anyway with that problem now solved, is their some sort of lens I can get so the laser will go further, I dont want a lens like what I got that makes a realy small dot but only for close up, after that its just huge, I need a lens that will keep it smaller and allow me to reach further distances, any idea on somet stuff I can DIY with household items or cheep things I can buy?

You need an adjustable beam expander, but 50mW won't go a long way....

Yea now see I dont want something that will make my laser larger but thiner for close up burning and long range shooting, no something where at 3 feet I will have a basketball sized laser dot. If the correct term for what I am looking for is actualy called a beam expander (strange since I dont want to expand it, lol) than my bad and im sorry but if it actualy is than those things close a crap load of money and I would be looking to build myself one.


And as for 50mW not being good well I love my 50mW and 6km range is good for what I need to do with it and it can light matches, cap gun caps, pop ballons and melt plastic bags and I dont need to take the IR filters off and like I said no mods on the laser in any way, shape or form. (But I do use the lens sometimes to speed things up alot)

There's lots of optics terms used here like collimator and beam expander which as I understand are the same thing -- a telescope. The beam expander enlarges the beam with a diverging lens and then a magnifying lens is adjusted to focus the beam at distance. Mine shrinks a beam from ~8" Dia down to ~2" at 150 yards. I'm using cheap lenses too.
Look into it - mine is removeable for the close fun stuff.

Mike

If you look in the mods and experiments section theirs a thread that talks about a Rifle Scope for a beam expander, would that be good for what I want, close up focus than long range beam expand?

It's called a beam expander because it does expand the beam, it makes it fatter.Even though you might think this is bad, actually a thicker beam can be focused better at a longer distance than a thin one(that's why you need an adjustable one).If you make your beam thinner , it will increase divergence making it more useless at distances, so basicly if you want long distance burning, a beam expander is your best bet.
I guess the daisy rifle scope mod should work well for your needs, you might need a little more power to compensate from the losses within the scope and to have more effect farther away.

Yea now see I dont want something that will make my laser larger but thiner for close up burning and long range shooting, no something where at 3 feet I will have a basketball sized laser dot. If the correct term for what I am looking for is actualy called a beam expander (strange since I dont want to expand it, lol) than my bad and im sorry but if it actualy is than those things close a crap load of money and I would be looking to build myself one.

Click to expand...

xJumper,
Just a note, the "beam expander" is usually just (2) lenses, as explained earlier, and if you reverse the order of these lenses, they become a beam-condenser, (which is what you are asking for, but maybe not what you want). So if you want to focus to a point at long ranges you will need to expand at the lense and focus to a point to overcome natural divergance. But if you make your beam expander removable and reversable, you can fire the laser through the magnifying lense first, and the expander lense will correct the beam into the now thinner beam. For instance, a 2x beam expander will make your beam twice as thick at the pointer, but your dot twice as small at a distance, pop ballons twice as far, reverse your 2x expander, and your beam will be 1/2 as thick as without it, but your dot will be twice as big at a distance, popping ballons at only 1/2 the distance. I started down the exact same road, I want a very thin Blu-ray beam, it is really a trade off.
If you want a less expensive alternative to the $500 beam expander on youtube, you could try one from Lasermate:
http://www.lasermate.com/optics.htm#Compact Beam Expanders
They offer 2x, 3x and 10x, I bought the 10x for $48+ which is way too much loss through the lenses, I would not recommend it for "thermal experiments", you lose like half of your power. When reversed it also makes a 10x thinner beam than with just the Aixiz lense alone, but it spreads out into a haze after about 12ft. Next I would try the 3x, I think these are $38. One note: these are made to screw into something like an aixiz module, except a little bigger, the Aixiz module uses 9mm threads, and these beam expanders use 11mm dia threads. You would have to come up with a mounting method, I am working on one.

Experiment with a monocular, binocular, or telescope to view these effects directly beofre deciding what you want to do.
Laser through the eye-piece= beam expander
laser through the objective lense= beam reducer
Alignment is critical, also, I understand reflections from the lenses back into your diode may damage the diode, just a warning.
Hope this helps, Good luck! ;D ;D
Dark Horse

Thats all! You realy helped me out in understanding all these things about lenses and beam expanders and stuff and im going to be picking up the right gear to make my own soon. Home Depo is the first stop on the list and then il use some old lenses from cameras and binocs and I should get some nice results for cheep.

xJumper,
I hope it helps, I have had quite a bit of trouble finding these few simple and practicle tid-bits of optical knowledge with regards to lasers, (and that is about all I have btw). More to follow, if you find anything practical, make sure and share I believe the optics are as important as the electronics.
Good hunting!,
Dark Horse

n fire the laser through the magnifying lense first, and the expander lense will correct the beam into the now thinner beam. For instance, a 2x beam expander will make your beam twice as thick at the pointer, but your dot twice as small at a distance, pop ballons twice as far, reverse your 2x expander, and your beam will be 1/2 as thick as without it, but your dot will be twice as big at a distance, popping ballons at only 1/2 the distance.

Click to expand...

Um, I think you got it a little wrong there.It makes your beam twice as thick and halves your divergence.This is not the same as saying "it will make your dot twice as small at distances".Well it depends on the distance, at the right distance it's gonna be exactly twice as small, but essentially , the farther you go, the smaller the dot WITH the expander than the dot WITHOUT the expander.The closer you are, the better it is without the expander.
And it's not gonna make your laser pop ballons from twice as far.Let's say that you have a 50mW with a 5mm thick beam and 1mRad that barely pops a ballon really close.Through the 2x expander it will be a 50mW 10mm thick beam with 0.5mRad and it isn't gonna be able to pop a balloon at all....

There really isn't a clear proportional relation between how many times the expander thickens your beam and the dot diameter at distances or the distance you can pop balloons at , like you said. :-/

Thanks for the clarification,
I did know that they were not directly proportional, but I was trying to keep it practical, It is more like a trigonometry funtion, with a modifier for the divergance. The longer the distance, the more divergence comes into play, although the beam expanders are often advertised this way, as a simple equation, but you are right, it is not that simple. Maybe it is slide-rule time?
It would be great to have some sort of FAQ on just the “laser related optic stuff” with a really practical "theme". Maybe a beam-shaping FAQ. For instance: my hypothesis-"simple telescopes, (2-3 lenses) will suffer from less light loss than telescopes with prisms". Is this true?, I think it is, the prisms help with keeping an image clear, and the telescope short, but we are only worried about a spot, not about a "distortion-free image”, and the thickness of the prism must rob us of a lot of power, but other than experimentation, I have no idea where to reference this info.
I have read the "Optics post", this was very informative and well done, but it left me with the feeling-"what do I do with my laser now?". Just knowing about using "telescopes" for these purposes, (for beam enlargement, or reduction), has made it so that I can experiment without developing an optical breadboard.(yet ;D).
Thanks for the info,
Dark Horse

one pass ( not the mirrored folded ones) binoculars work well i have some old ones that only use 3 lenses so not much loss and they work good as a expander or condenser ( depending on which side i put it through) they make my 3mm green beam 8x wider and that looks great as a light saber