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How To Turn a Mini Maglite Into a Laser
Lucas123 writes "Using the laser from a DVD burner, this instructional video shows you how to create a hand-held laser that is powerful enough to light a match and pop a balloon. There's some soldering involved and the Maglite's bulb housing needs to be drilled out to fit the new laser diode, but with some basic skill, most people could do this. Just plain cool." Update: 07/09 12:23 GMT by KD : Warning, the device that results from following these instructions will blind you if you look into it.
So basically you're not making a laser, you're just moving a laser from a drive into a flashlight case.
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Know what I'm doing this weekend :) now if only this could be modified for Laser tag
actually ignite a match like that? I didn't know that 2 AA batteries could put out that much power in a laser beam... this is clearly a lot more powerful than your standard run-of-the-mill laser pointer used in presentations. I'm so tempted on doing this.
~ In Trust, We Trust ~
Now when I go to the movies, instead of worrying about Brad Pitt having a red dot on his face, I have to worry about the screen igniting. Good times.
In the words of Rainier Wolfcastle:
My eyes! The goggles do nothing!
So where did I put those frikin sharks?
Ok, so where do I get the shark ? and where is the manual on how to mount it on the shark ?
"Do not look into Laser with remaining eye!"
"To those who are overly cautious, everything is impossible. "
Nope. None of those things.
Articles about making lasers? Yes! Yes! It can light things on fire too?
Excuse me. I think I may have just wet my pants.
Custom, hands-free Linux installs. Instalinux
DVD players use a red laser; presumably Blu-Ray players use a blue laser (though why you're cannibalizing the operative piece of a $1k+ piece of... oh, wait, maybe you already converted your PS3 into a grill)... but there isn't anything that uses a green laser that's readily obtainable, is there?
"Is that necessary? Is it just a metal tube or does it serve a more substantial purpose."
Yes.
Now do you understand why they don't allow optical media writers in your carry-ons?
Next week...how to turn a laser into a repeating rifle - all part of our DIY Firearms Convergence Series, here on the 'Defending the Homefront' Channel. Brought to you by 'Ahmed's Security Stuff' - at ASS, we pick up on the first ring!
There's going to be a lot of blind hackers in the next couple of weeks. If you're smart, you'll figure out how to wrangle this as workmans comp before you build the thing.
I like music
The problem isn't the current draw - it is the heat. The big laser pointers tend to ensure there is better thermal coupling to the case so the waste heat is removed. With this, it will tend to heat up the module until pssst... and your laser is dead. Should be ok for less than a minute or so.
I see you have constructed a new lightsaber. Your skills are complete, indeed you are powerful as the emperor has foreseen. - Darth Vader
Sorry about the writing. Robot fingers, you know? Cliff Steele in DOOM PATROL #23
Is that a strange way of pronouncing 'soldering'?
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
Think of (all?) the people who now have a good use for their BluRay players. ;P
What part of "This product contains a Class 2 laser. Do not power on without enclosure" did you not understand? This has the potential for causing serious bodily harm, including but not limited to permanent blindness!
"No problem. I have the capacity to do infinite work so long as you don't mind that my quality approaches zero."-Dilbert
A shorter wavelength laser will have more energy. Ultraviolet would be the best. Unless you modify the laser module's circuit, using bigger batteries would not make any difference to the output other than the fact that they will last longer before going flat.
If you can pop a balloon with it, it is probably in the 100mw range which is enough to do permanent eye damage in 1/100th of a second. That's faster than you can blink. You won't go blind instantly, you'll just burn out a bunch of optic nerves, producing a 'hole' in your vision. Chances are, your brain will correct for the hole and you won't even know its there, unless an object ends up right at that point in your field of view, at which point it will 'magically' disappear.
When information is power, privacy is freedom.
Yes. But the main problem is that you need some way to limit the electric current through the diode. Laser diodes behave a bit like LEDs, electrically: below a threshold (2.5 V or so) there is little current and they don't do much, and above that threshold, every 0.1 V you add will increase the current and light output enormously. Too much current and the diode will die in a matter of seconds. Apparently the laser diode he used was just right at 3 V from two penlites, although I doubt that he had a calibrated laser power meter to measure whether the output power matched the nominal power rating for the diode. The simplest way to limit the current is to use a higher voltage and a series resistor. Something else is that the laser assembly in different optical writers sometimes doesn't have the collimating lens attached to the laser diode itself: without lens a laser diode produces a very divergent beam.
Now for safety: I work with fairly high-power lasers (up to 25 W) for a living and consider a hand-held 250 mW laser in the hands of someone without appropriate training in laser safety hugely irresponsible. According to the IEC60825 standard on laser safety, 200 mW will lead to permament eye damage within 1 microsecond (!) of exposure. The reason laser pointers are restricted to 1 or 5 mW (depending on the country) is that for those powers, eye damage will occur after 0.3 seconds, which is about the time for the blinking reflex to close your eyes in the event of accidental exposure. Unexpected reflections from things like glass can be up to 10% of the beam power - 20 mW (eye damage in 10 microseconds).
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So you could do some real interesting things with a Blu-ray diode then...
Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
Sure, cool and simple it is, but do you want to start placing bets on how many people are seriously going to think before pointing this at a mirror? This is the kind of article you'd expect to have a page of safety instructions in big flashing letters before ANY instructions. Free speech it is, but the author AND editor need to have some fscking sense of responsibility, too.
. . .but read and understand the safety FAQ first:
http://www.laserfaq.org/sam/lasersaf.htm#safssl2
Torben
How long will 2 AA batteries last shooting so much power ?
My
MY EYES! The googles do nothing!
"Things are more moderner than before- bigger, and yet smaller- it's computers-- San Dimas High School football RULES!"
Re: Is the metal housing really necessary? ....Yes, for the most part.
....Mine didn't work because I could not find a way to get the laser diode out of the original steel heatsink it came in. It was glued inside a hole about 6mm deep in a odd-shaped steel heatsink. You could maybe grind the heatsink away a bit at a time with a Dremel & cutoff wheel, but laser diodes are sensitive to heat, so you cant let the laser get too hot. I tried using mine still in its heatsink with other optics (telescope objectives and whatnot), and with those set in front of it, it would melt a garbage bag a little but wouldn't do much else.
I tried this some time back, and it didn't quite work, but I'll relate what I know anyway:
1. There's TWO laser diodes in a DVD burner--remove them both out carefully, preserving as much of the leads already-soldered-on as you can! The leads of the laser diodes are very short (maybe 2mm) and only about a half-millimeter apart, it's damn tough to get the longer leads soldered back on if you cut them off, and there's no need to cut them off and then attempt to solder them back on anyway.
2. Inside the DVD burner you will find TWO laser diodes, with mirrors that feed them both into the same beam. Each will be glued inside its own heatsink, a piece of metal that may be a very odd shape, and then these are attached to a bigger copper plate. To tell them apart, just test them--try applying 1.5V power to both diodes one at a time, the CD one is IR and won't appear to do anything. The DVD one will light up visible red. (if all the lenses are removed from them at this point, you cannot burn your eyes out, that's in the next step...)
3. The bare laser diodes don't put out a laser "beam", they just create a pinpoint light (that's safe to look at!). To get the beam, you must mount a fisheye lens with its concave side set very close to the diode, almost touching it.
4. The laser housing is a metal tube with a fisheye lense set in it. The laser diode will get warm with 1.5V on it, and will get too hot to hold in ~30 seconds with 3V on it. The laser housing serves partly as a heatsink, and also as a way to hold the lens without melting (the DVD-drive optics will have a fisheye lense, but those optics are usually set into little plastic frames, and they may melt in this use).
IF you manage to get one out and do this, don't run it for more than ~20 seconds at a time without letting it cool down for a minute or so. The laser diode will work with 3V batteries hooked straight to it, but you're definitely not going to get that 100,000 hour lifetime. You'd be lucky to get 1000 hours. The DVD laser output power is typically around 210mW, and more than 150mW is enough to burn stuff (the CD laser won't burn stuff because it's only around 40-50mW max).
~
Green lasers can put out more energy because of their design in general. Now from the demo, it looks like this red diode is more powerful than the ones normally used in laser pointers, not sure on its power. I don't know what the maximum is, but it is in the 100s of mW. I don't know about the orange or blue diodes, haven't really looked at them. The problem is that they are rather expensive so I don't think you'll want to buy them. D batteries have the same voltage as A batteries, just more storage capacity. So using those will make it last longer. As a practical matter, the voltage you feed it needs to be whatever it was designed to take, so if 3 volts is what is called for, do not go over or under that, you'll probably just screw up your stuff.
One thing to note though is that green laser are more complicated. There isn't actually a single diode that does green, rather it is an IR light that's generated and then frequency doubled to make green. In fact one would probably get more energy per square mm by simply using the IR output. Of course that is even more dangerous since you can't see IR and thus could be lasing your eyes and not know it.
Before you do this, note three things:
1) You can buy lasers over 5mW commercially. Just search Google for it, it isn't illegal or anything.
2) To own and operate any laser over 5mW requires a license. You are responsible for getting it from the FDA.
3) Messing with high power lasers (and yes over 5mW is high power in the laser world) is rather dangerous. That's why there's the limits. If you have a 100+mW laser, which is around what you'd need to light a match, even the reflected light could damage your vision permanently if you hit your eye. Given that you don't seem to know much bout lasers, best not to fuck around with this. Consider that the sun provides about 1000 watts per square meter to the earth, and that looking right at it will damage your sight in a few minutes if you aren't protected. That works out to about 1mW per square mm. So take a laser, who's dot is only around a square mm or two, then consider its power. Yes, it really is brighter than the sun. When you are talking about some of these high power 3B lasers, they are MANY times brighter than the sun. Don't play with powerful lasers until you learn about them.
You are wrong! Great freedom comes with great responsibility, and freedom of speech does not have to be harmful.
Freedom of speech or not, it is irresponsible to tempt people with limited or no knowledge to mess with technology that is likely to blind them or others. There is no age limit for readers of this site, so you have to assume that you might be speaking to teenagers or even kids. I would have thought that americans, with their love of lawsuits, would have learnt that by now.
Especially IR lasers (invisible lasers) are dangerous, because they will damage your eyes and you will not even blink or know what happened. The first thing that happens is you feel pain, and the damage is done.
Kids, have a game of soccer instead.... you might actually get a tan and some friends
Pepper spray? My balls! Nothing to teach an assailant a lesson like losing vision in one eye.
actually the one thing I am VERY interested in is if can produce enough pinpoint heat to start a flammable liquid on fire from a distance...oh.. I think I just came.
"Thank you for using Stop-n-Drop, America's favorite suicide booth since 2008"
Please remember not to look at them with your remaining eye
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In all probability, the batteries will probably limit the current all by themselves - AA batteries typically are fairly high impedance sources and just can't deliver an awful lot of current. I have high power LEDs without much in the way of current limiting because the impedance of the battery (plus the Rds(on) of the MOSFET that turns them on) is such that the current is a little less than nominal (300mA rather than 315mA, with an absolute max. of 550mA).
Oolite: Elite-like game. For Mac, Linux and Windows
What the article doesn't, and should say:
This is a very dangerous toy
IT WILL BLIND YOU IMMEDIATELY IF:
- You look at it
- You shine it on a reflective surface that shines it back into your eye
No joke, people. Don't try this at home. I'd actually argue that this video is irresponsible since it does not mention the dangers of the item being built at any point. It will probably be uploaded on Youtube and a lot of innocent, curious kids will end up with one fewer eye as a result of this video.
DO NOT USE UNSAFE LASERS WITHOUT WEARING THE APPROPRIATE PROTECTIVE GEAR (special goggles can be obtained for specific wavelengths, which will ensure that you cannot see the laser - and hence it can't hurt you).
Daniel (who was paying attention during the Physics Dept 'laser safety' lecture)
Carpe Diem
I seriously hope someone sues the fuck out of this guy SO badly that he'll never be able to afford a flashlight or a DVD burner again.
I'd rather get shot with a gun than be blinded with that thing. And unlike guns, any asshole (or kid) can assemble one from parts, with absolutely no regulation, and leave me permanently blind.
Don't realize how bad this is? OK, imagine this: Someone brings this to a disco and points it towards the revolving sphere = dozens blinded, permanently. This is not a joke. This can be used for terrorism, pure and simple.
Such weapons are illegal under the Geneva Convention, as is any other weapon expressly designed only to maim. Laser weapons also have further clarification in the form of The UN Protocol on Blinding Laser Weapons.
Weapons that do maim are undeniably effective, since it not only deprives your enemy of the soldier, but also the resources required to provide him with medical attention, and to support him when he is no longer able to be productive. Anti-personnel land mines are the chief example of weapons which fall into a grey area here - most of them are potentially lethal, but most often fall short and leave their targets maimed.
There have been various plans to produce merely incapacitating light-weapons, but in practice, it is difficult to produce a device than can dazzle your opponent without at least some chance of permanent damage.
Bush: We've go to do something to get rid of all those dangerous hackers.
Vader: Perhaps we could post a video showing them how to make a dangerous weapon that they would accidentally use on themselves.
Jobs: Hmmm... there's a dangerous laser in DVD burners.
Gates: Yeah, let's hope that works better than your plan to make them all deaf with your stupid iPod, or get them run over walking across the street, playing with their iPhone.
Place nail here >+
Or do you think a DVD reader or CD writer will do?
sigs are hazardous to your health
Laser diodes generally require some type of current limiting to prevent damage. In the DVD burner circuit, that is the function of the third pin on the diode package (that the article simply blows off as "not used"). This pin connects to an internal photodiode, which is used to measure output power, and provide feedback through an external driver circuit to continuously control the current applied to the laser diode junction.
The article simply places the laser diode directly across the 3V battery supply, with not even a ballast resistor to limit the current. You might get away with this with AA batteries, but if someone were to try this trick with a D-cell maglite, they would most likely let the magic smoke out of the laser very quickly.
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Do not meddle in the affairs of lasers, for you are soft and absorptive.
Anyone know an inexpensive source for protective gear (ie goggles) for those amateurs who will insist on playing with something like this, but would like to do so responsibly?
(And thanks to dhalgren for the very helpful Safety FAQ.)
A laser from a DVD burner is 200-250mW or thereabouts. You can legally (in the US, anyway) buy ready-made laser "pointers" of comparable power. For example, wickedlasers.com sells the handheld 200-300mW Spyder II GX green laser with 1.5mm diameter beam and beam divergence below 0.8 mrad. Red lasers up to 125mW and blue lasers up to 30mW are also available.
No, I don't have one. They're almost certainly illegal in my country.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
Laser Standard Operating Procedures
Laser Safety
Check your particular DVD Rom, chances are fairly good that it's rated as a class I laser (non hazardous, but try not to stare directly at it...because like everything else it's probably made in china I wouldn't be surprised if to save a penny they underclassy the mW output to skip a safety inspection over in the usa heh)
However, if it's a class II....
The reason I am offering these links is because I doubt many people know that a class II laser beam will cause eye damage within as little as .026 seconds?
1-2 seconds could be more than enough to cause snow blindness style affects, headaches, and temporary eye tissue scarring?
I got caught not wearing my ansi rated safety goggles at corning from a light gun and I couldn't see for about 3 days (snow blindness from intense UV exposure for 2 seconds). So let's practice some good sense people.
[so much for the modding I'd done in this thread.]
Due to an infection I obtained when I was 2, I've got partial blindness in both eyes. The infection caused scar tissue to form on my retina smack in the good part (center of the optic nerve junction) of my left eye. I can see objects and make out large things but I can't read with that eye at all. Think of it like your peripheral vision. Try this: put a page of text a foot from your ear and try to read it--while looking straight ahead. That's what my vision is like when I close my right eye.
The right eye has some similar damage, but luckily the scar tissue formed only over a smaller area which is not positioned over the center of the optic nerve junction. So back to the parent's comment about your brain compensating, I can tell you from experience--it depends on how much damage there is. I can read, I can drive and so on, but my brain has to work a bit harder to make a complete image. I don't have 20/20 vision (even with glasses), it's more like 20/50. (I can read text at 20 feet that you can read at 50 feet.) I have to hold things closer to read them than most people, and it's pretty hard to read road signs while driving.
So the moral to the story is twofold:
1. Sandboxes are bad, toxoplasmosis bacteria likes to grow there and kids that play in sandboxes inevitably will rub their eyes.
2. Don't mess with lasers. Holes in your vision--not cool.
(I almost died laughing when I saw the "donotlookatlaserwithremainingeye" tag. I have a special place in my heart/right-eye for that line.)
So did I, to be honest, although never several seconds. But: at 1 mW (visible light), the MPE (maximum permissible exposure) is about 1 second. The MPE represents the largest exposure which under worst-case circumstances does not lead to eye injury for 90% of the population. Worst case means that the eye and the laser source are stationary over the given exposure time, and that the eye lens is focused such that the laser light is concentrated onto the smallest possible spot size on the retina. If the eye lens is a bit out of focus, resulting in a blurry spot, you have some extra margin. I think the MPE values take into account that the eye is never completely motionless.
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As I said in another post, DVD burning uses lasers rated for over 200 mW. You can buy a DVD burner for under $40 and strip out the laser, or you can often buy replacement/repair carriages for burners on ebay for even less.
I haven't yet seen a straight green laser diode -- mine are all frequency doubled. However, many new green LED's are created using silicon nitride, essentially being blue lasers that emit at a longer wavelength, and it's not clear to me why they couldn't do the same thing with a blue diode.
Lasing your eyes with IR sucks, but not as bad as with visible, because the front of your eye is mostly (*mostly*) opaque to IR so you'll just fry your cornea, which can be replaced. Visible will go through the eye optics system, get even more focussed, and fry holes in your retina, which is not repairable. I've worked with people who have gotten big blasts of UV, IR, and green, and only the people who got hit with green had blind spots in their vision. The others had to wear glasses or have lens/cornea replacements, but they had reasonable vision despite that.
Nostalgia's not what it used to be.
A lot of people here have mentioned how dangerous this laser is in terms of the ability to fry eyes and/or cause blindness. Is there anyone here who can indicate what the proper safety gear would be when dealing with lasers of this variety? I'm guessing that anti-UV sun-glasses aren't quite good enough... and welders goggles perhaps a bit too dark to accomplish any work?
informative?
Funny, mayhaps. But informative? No.
God have mercy on their heathen souls.
Faster! Faster! Faster would be better!
Just hit 'em with a hammer!
SAFETY WARNING: Don't hit bullets with hammers!!
SECOND SAFETY WARNING: Because hitting a bullet with a hammer can cause it to explode!!
THIRD SAFETY WARNING: A bullet moves very fast and can kill or injure anything in its path!!!
FOURTH SAFETY WARNING: YOU COULD EVEN YOUR EYE OUT DOING THIS!
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
The optical DRIVE is class I, because it's enclosed by a metal box and has interlocks, thus posing no danger if operated normally. The diode inside can be class II, III, IV, or whatever. Every DVD drive would have similar power output, since that's what it takes to burn DVDs.
If you shine the beam into your eye - on purpose, by accident - or by bouncing it off of something shiny, it will burn holes in your retina. That's not "may" that's "will". We're talking about permanent eye damage, the kind that makes people blind.
Operating one of these in your house or outdoors is dangerous not only to yourself but to others. Our world is full of shiny things; even imperfect "mirrors" can reflect enough beam energy to harm yourself or an innocent bystander; just one quick "flash" sighting of the beam's reflection is enough to cause permanent eye damage.
I know that there's too many of you who will say "it'll never happen to me" and go happily waving your new super laser pointer around. I have one helpful tip for you: if you have a "wow, that's bright!" experience followed by things getting darker - get yourself to the hospital RIGHT NOW and tell them you got a look at a class IIIb laser. They'll know what to do and can probably save your eye if you get there soon enough.
Laser safety goggles are a great idea - but only if you're playing with your laser indoors in a room with all windows covered and all shiny / reflective things removed or covered. If you take it outdoors and start waving it around, someone's going to get hurt.
Visible means little when you're blind.
Warning: Do not look into LASER with remaining eye.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way