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How To Turn a Mini Maglite Into a Laser
Posted by
samzenpus
on Thu Aug 09, 2007 12:59 AM
from the a-thousand-tiny-burn-marks dept.
from the a-thousand-tiny-burn-marks dept.
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.
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Uhhh... (Score:5, Informative)
Re:Uhhh... (Score:5, Funny)
Parent
Dangerous (Score:5, Informative)
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)
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Re:Dangerous (Score:5, Informative)
TO EDITORS: PLEASE ADD SAFETY WARNING TO THE ARTICLE SUMMARY!
This is an irresponsibly dangerous video with no safety warning.
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Re:Dangerous (Score:5, Funny)
Next week on
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Re:Dangerous (Score:5, Informative)
http://www.telegraph.co.uk/news/main.jhtml?xml=/n
http://www.criminal-information-agency.com/firear
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Re:Dangerous (Score:5, Funny)
Jacking up the power like this make the ENTIRE BEAM visible, not just the point.
I still want a laser powerful enough to deface bumper stickers and write insults into the paint on cars...
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Re:Dangerous (Score:5, Funny)
Visible means little when you're blind.
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Re:Dangerous (Score:5, Funny)
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Re:Dangerous (Score:5, Funny)
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Re:Dangerous (Score:5, Informative)
I was in a foreign country. The company I worked for rushed me to hospital and this foreign doctor explains to my collegues that she needs to inject a needle in behind the back of my eye. You need to prevent the back of the eye from bruising and swelling up.
She takes out her book of english and says slowly "This will..... hurt". And it did.
Thankfully after 2 weeks my eyesight was back to normal.
So please everyone - do be very careful. And if anything happens, it is _vital_ to get to a _eye_ hospital as soon as possible.
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Re:Dangerous (Score:5, Funny)
If I wet the bed, I'm sending you the laundry bill.
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Re:Dangerous (Score:5, Funny)
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Re:Dangerous (Score:5, Informative)
As it turns out, my injury was severe but not nearly as bad as it might have been. I was not looking directly at the prism from which the beam had reflected, so the retinal damage is not in the fovea. The beam struck my retina between the fovea and the optic nerve, missing the optic nerve by about three millimeters. Had the focused beam struck the fovea, I should have sustained a blind spot in the center of my field of visions. Had it struck the optic nerve, I probably would have lost sight of that eye.
The beam did strike so close to the optic nerve, however, that it severed nerve-fiber bundles radiating from the optic nerve. This has resulted in a crescent-shaped blind spot many times the size of the lesion.
The diagram is a Goldman-Fields scan of the damaged eye, indicating the sightless portions of my field of view four months after the accident. The small blind spot at the top exists for no discernible reason; the lateral blind spot is the optic nerve blind spot. The effect of the large blind area is much like having a finger placed over one's filed of vision. Also, I still have numerous floating objects in the field of view of my damaged eye, although the blood streamers have disappeared. These `floaters' are more a daily hindrance than the blind areas, because the brain tries to integrate out the blind area when the undamaged eye is open. There is also recurrent pain in the eye, especially when have been reading too long or when I get tired.
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Re:Dangerous (Score:5, Funny)
Pussy.
I've got one sitting right here on my desk, and I can shine it in to my eyes with absolutely no problems. Allow me to demonstrate...
Srr?
Sbao;utelu ni orpbkens,
Parent
Re:Dangerous (Score:5, Funny)
This is a very dangerous toy
IT WILL BLIND YOU IMMEDIATELY
Humbug! All my life they have been telling me masturbation does the same exact thing.
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Re:Dangerous (Score:5, Funny)
- RG>
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Re:Dangerous (Score:5, Insightful)
The only saving grace in this article and video is that the beam will hopefully not be that well collimated over a longer distance and when idiots shine it at other people, the damage will be less and the people will have time to look away before they get serious damage.
Also, a laser like this would probably leave lines or dots burned into the retina. It isn't as bad as a pulsed laser that can literally rip the retina off the back wall of the eye because of what are essentially sonic booms in the eye due to the fast rise times and heating pulses. But if it can burn a hole in a piece of paper, imagine what it can do to all your rods and cones when your eye focusses the beam into an even smaller and more intense spot in your eye.
I agree with all the other posters who say the video should be removed and that this article should be pulled.
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Re:Dangerous (Score:5, Insightful)
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Re:Dangerous (Score:5, Informative)
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Re:Uhhh... (Score:5, Funny)
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Great... (Score:5, Funny)
Careful with this thing. (Score:5, Funny)
My eyes! The goggles do nothing!
To repeat an old warning (Score:5, Funny)
Re:To repeat an old warning (Score:5, Informative)
Parent
This is why I read Slashdot (Score:5, Funny)
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.
Re:This is why I read Slashdot (Score:5, Funny)
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Re:This is why I read Slashdot (Score:5, Funny)
At least be complete, you insensitive clod.
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Young Skywalker (Score:5, Funny)
BluRay (Score:5, Funny)
Um, *excuse* me!? (Score:5, Informative)
Re:Um, *excuse* me!? (Score:5, Funny)
Oh, sorry. I was channeling a 14 year old emo girl for a minute.
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Dumbass in the comments (Score:5, Informative)
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.
Re:Dumbass in the comments (Score:5, Informative)
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I know about dead optic nerves (Score:5, Informative)
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.)
Parent
MY EYES! (Score:5, Funny)
Meanwhile, back at the White House, a plan develop (Score:5, Funny)
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.
Laser diode may not last too long run like this... (Score:5, Informative)
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.
Laser Safety, Standard Operating Procedures, Gear (Score:5, Informative)
Laser Standard Operating Procedures [csulb.edu]
Laser Safety [csulb.edu]
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.
Re:Sounds like fun. (Score:5, Funny)
Parent
Re:Nice timing (Score:5, Informative)
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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Re:Shark (Score:5, Funny)
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Re:Shark (Score:5, Interesting)
Just turn the shark upside down before mounting, that makes it go into tonic immobility for about 20 minutes.
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Re:Shark (Score:5, Funny)
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Re:Shark (Score:5, Funny)
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Re:This makes me sad. (Score:5, Informative)
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Re:Laser Housing (Score:5, Interesting)
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).
~
Parent
Re:Sure (Score:5, Informative)
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.
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Re:Mods, wake up! (Score:5, Insightful)
If someone is dumb enough to use the information and blinds himself, he's the only one to blame for it. That something like this is harmful should be obvious. If it's not, this is due to the person having not enough information on the subject to see the problem.
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Blinding lasers are banned. (Score:5, Informative)
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 [wikipedia.org] without at least some chance of permanent damage.
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