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ArcticMyst Security by Avery

Learn From Mistakes That Can Happen To Anybody...

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Lets see...

I have fried a rather painful hole into my palm putting batteries in my 2.2W 445nm with a G1 set to very close range focus for a burn I was working on. Lesson: Never put the tail cap on with the laser facing you or without a cap on the lens or both.

I have, fried a Mitsu 300mw with my bench PSU due to a lose wire being bumped and the weak connection sparking. Lesson: always make sure your connections are solid and never touch wires actively powering a diode.

Pulled my Osram 450nm build reaching for a flashlight and momentarily flash blinded myself when the beam hit my hardwood flooring. Lesson: Duh... now all my lasers are kept without batteries in them and in a box.

ESDd an M140 walking across my house wearing socks on carpet. Lesson: always protect diodes in ESD protection bags and short the pins for storage/transport.

Burned a spot on my computer screen setting up my bench test rig with a S06J and couldn't see the beam with my goggles on. I realized it was on when I heard a sizzling sound... Lesson: never mess with lasers around expensive screens. Always assume the laser is powered up and act accordingly.

Good thing I learn fast...
 





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owch! I have a bunch to tell too but nothing that awfull Is there a fund I can donate to for dumb asses that burn out there eye's??? I may need it someday!!! just spent another 180$ on goggles for the project.. Truth hurts the pocket. Saves the EYE'S. I will fire up the 5W after I get my goggles..
 
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Luckily the flash blind only lasted a short time because the beam only flashed across my face and was slightly diffused. There is no instantly apparent permanent damage from it luckily. After a while everything looked normal again(colors were off a tad) so I don't think the beam went straight into my pupils but rather hit my irises. I didn't see an optometrist since nothing hurt and I didn't get a headache and there wasn't any blind spots left behind. I think I was damn lucky on that one.

I am normally the one who wears goggles indoors but that time I was expecting a flashlight and not a laser...
 
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Jun 25, 2011
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i've had Another mishap with my 12x phobos. a bit of teflon got stuck on the window:wtf:
it destroyed my beautiful single mode spot and seriously dropped the output.
what to do?:thinking: i used the search function!
i read about de-canning. i knew i'd screw that up even if i removed the diode from the module intact. then there was info on cleaning it with iso and acetone. so i tried acetone and q-tips - lots of them.
and it worked:thanks:
lesson learned: keep it clean and go EASY on the teflon. the layer i had wound onto the lens housing had frayed and just the smallest bit made it to the window. i was very lucky that it didn't burn into the window and was just stuck onto it.
the nice tight dot is back along with all 585mW of 405 goodness:wave:
 
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Thats exactly the reason I use an internal and or an external spring. I do not want to have to deal with teflon tape getting stuck to my diode window nor do I want to have to bother replacing it.

I also found that the tiniest spec of damping grease on the threads makes for a super smooth focus and can be wiped off if you don't want it anymore. I pretty much only put it on lenses that I have no intention of swapping out though.
 
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Always wear your safety glasses while inside, if I did not have them on when lighting a candle I would be blind as the wax reflected the 1498mw 445 beam after it meled into a drop. It hit my goggles no perma eye damage yay for me
 
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Always wear your safety glasses while inside, if I did not have them on when lighting a candle I would be blind as the wax reflected the 1498mw 445 beam after it meled into a drop. It hit my goggles no perma eye damage yay for me

Lol, I did just about the exact same thing lighting a candle with my 2.2W 445. Thankfully I already possessed the intelligence enough to wear my goggles beforehand as well. Yay for not requiring that to be a bad lesson?

Another story:
I was shining my 9mm 445nm with a fresh set of IMRs in it across my basement like I always do to focus for infinity and my buddy walked in and thought it would be amusing to wave his hand through the beam. Unfortunately for him, He chose the exact spot where the beam hit super focus which was about 4 feet from the lens(stock lens on it at the time). The burn resembled a cut that I would expect off a razor blade rather than burning it. I suspect this is because it was so insanely fine focused that it created enough heat fast enough to melt(or something?) his skin rather than just burn it.
 
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Jul 22, 2012
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If your diver requires you to run the ground through it, remember this if your laser diode is case negative! I once built a driver with a LM2941CT which requires you to run the ground through it, I forgot this and I have been waiting for a month to receive a LPC-826, and I was just about to put it in the host when I got a little excited and wired the ground directly to the heatsink. The little diode got 12V from my power supply and went to laser heaven:angel:.... after a total of 2 minutes run time:banghead: May he LED in peace:cryyy:
 
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My mistake is letting my dad find out that u I owned highnpowerd lasers just when the law came into place here in Australia. My dad who I do t get along with told the cops and $300 worth of lasers got confiscated .
he doesn't live with me so I restarted my collection about 3 years ago.
 
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Mar 24, 2013
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No story here.
Awesome thread, I just read through it even though I dont know what half of what you are saying means.
I've not built my own laser before, but ive got a 30mw and a 50-80mw green laser
Looking forward to making some mistakes with you guys. :) lol
 
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I pointed my 200mW 650nm into a mirror and the beam reflected straight back at the laser and destroyed the diode in a split second... Only using mirrors from angles from now on
 
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How close to the mirror was the laser? I believe it is very unlikely that the beam went so perfectly back into the diode that it killed it unless you basically stuck the laser against the glass. On a few occasions I have had high powered 445nm lasers accidentally reflect back at themselves while trying to set up mirrors 6 inches away and never had any issues.

Not to mention the losses from beam expansion(increased with distance), passing through the air(increased with distance), passing through the glass on the mirror both directions, losses from reflection(mirrors are never perfect), and then traveling back through the lens would drop the power quite considerably.

You may want to look into the possibility that the diode's death was caused by something else and just had an interesting timing.
 
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How close to the mirror was the laser? I believe it is very unlikely that the beam went so perfectly back into the diode that it killed it unless you basically stuck the laser against the glass. On a few occasions I have had high powered 445nm lasers accidentally reflect back at themselves while trying to set up mirrors 6 inches away and never had any issues.

Not to mention the losses from beam expansion(increased with distance), passing through the air(increased with distance), passing through the glass on the mirror both directions, losses from reflection(mirrors are never perfect), and then traveling back through the lens would drop the power quite considerably.

You may want to look into the possibility that the diode's death was caused by something else and just had an interesting timing.

A solid 8 feet away. The MILLISECOND the beam reflected directly back onto the laser it died, basically giving nowhere over 5mW output as it's best... (It still lased, but was hard to even see it with a bit of light, I got a good shot of it with high ISO). You can read my thread HERE.

Here's some content from a thread I posted a while back;

14wyf6q.png


40694d1358983324-laser-mirror-reflection-pics-untitled.png
 
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Amalan

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Please do not judge me on my use of this, but I have a <5mw presentation laser pointer in my car (the only one I keep in my car) I use to circle street signs (like no turn on red except for curb lane and the car infront of you is sitting there waiting for green, I pull it out and start underlining except for curb lane instead of blaring my horn a few cars back, I consider it polite road rage)

but I did this to an old lady on a speed limit sign cause she was going 5 below, she didnt find it amusing and went down 10 below.. thats the last time I messed with the elders. lesson being, respect your elders.
 
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A solid 8 feet away. The MILLISECOND the beam reflected directly back onto the laser it died, basically giving nowhere over 5mW output as it's best... (It still lased, but was hard to even see it with a bit of light, I got a good shot of it with high ISO). You can read my thread HERE.

Here's some content from a thread I posted a while back;

-img snip-
-img snip-

I still believe it to be highly unlikely especially at 8 feet. I would estimate that after losses you would get less than 100mW actually returning back into the module. IDK, I just find it hard to believe that it would be enough to instantly kill the diode. I guess its physically possible just insanely unlikely.

@Amalan
Personally, I do not bother trying to point mistakes out to people who are clearly too unintelligent to grasp the error since almost every time they will just jump to anger towards you and learn nothing because they are in denial of being unintelligent in the first place. At least that's what I have observed. Lol, I mentioned this once to my Dad and he thought it was highly amusing and agreed.
 




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