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How I got my laser eye injury

funraniumlabs.com

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Re: How I got my laser eye injury

#211

Post by rtkwe »

hinkley wrote: post #190
rtkwe wrote: post #182

Earlier quoted context omitted.

It's a scanning dot moving fast enough to appear as a cone.

The stationary ones used to have a spinning mirror with a laser pointed at it. You used to be able to look in the machine and see it. Dunno how they do it now for the handheld scanners. Smaller mirror or some other trick like piezo?

Hand scanners for a while have been able to use just LEDs to illuminate the barcode it turns out. Way cheaper than having so many moving parts like the older laser based scanners.

Re: How I got my laser eye injury

#213

Post by cyberax »

hinkley wrote: post #184
convolvatron wrote: post #134

Earlier quoted context omitted.

I tig. wear a helmet and have to buy argon every year. this seems like a huge hassle in comparison. is there that big a difference in quality and or range of processes that make it worth it?

I know one of the reasons we wanted pico-second and shorter pulsed lasers is that they can cut material with little to no damage of the neighboring material. There was a demo that I read about when this was all brand spanking new research, where they claimed that a laser scalpel causes no heat damage to tissue outside of a cell’s breadth from the contact point.

That's how LASIC and PRK work, after all!

Re: How I got my laser eye injury

#214

Post by Lramseyer »

anonymousiam wrote: post #178
NotYourLawyer wrote: post #163

Earlier quoted context omitted.

“Low power” lasers are sometimes wildly more powerful than they claim to be. I guess what do you expect when you buy a Chinese laser pointer on Amazon for 5 bucks.

Nd:YAG lasers such as the one in the article use an IR exciter into a crystal to achieve frequency doubling or tripling. Much of the energy from the fundamental exciter makes it past the crystal, so without good filtering, a "safe" class 2 or 3R laser can still produce blinding (but invisible) light. Lots of the cheap lasers don't have good filtering, so be careful what you buy.

Don't forget that the power rating of a laser pointer (unlike literally every other type of light you buy) is the output power, not the input power! More importantly, it's the output power of only the green laser!

The 1064nm exciter laser is pumped by an 808nm pump laser, and based on what I know about how inefficient lasers are, I can guarantee that those beams are way more powerful than the output beam! If those leak because the manufacturer cheaped out on filters, those lasers mat not visible, but they are still dangerous!

Re: How I got my laser eye injury

#215

Post by shaftway »

peepee1982 wrote: post #107
khorne wrote: post #82

Earlier quoted context omitted.

Save $300 on a vasectomy.

They're about twice as much where I live!

Most US insurance will cover this at 100% even if you haven't met your deductible. Something about how babies cost more than a 3 digit outpatient procedure....

Re: How I got my laser eye injury

#216

Post by queuebert »

tlb wrote: post #100
DannyBee wrote: post #17

So I laser weld, and beyond my own PPE, interlocks (gun won't fire if it's not touching metal, etc), the most important part of the whole setup is laser safety curtains. Because it's a 2500 watt laser, if i didn't have laser safety curtains , the relections/etc could very easily blind someone at a fairly long distance. The NOHD (nominal ocular hazard distance) is something like 10km (2500 watt laser, 0.06mm spot size…

Why don't welding/cutting lasers add more divergence with built-in optics? Would it hurt performance? It seems like you could add 1 mrad and it would hardly make a difference at the usual working distance, but spread out to a meter over 1 km, so you can't zap people across town.

Whatever refracts the light will have to stand up to the beam for long periods of time. Maybe it's a materials science problem.

Re: How I got my laser eye injury

#217

Post by yard2010 »

elif wrote: post #85
DannyBee wrote: post #17

So I laser weld, and beyond my own PPE, interlocks (gun won't fire if it's not touching metal, etc), the most important part of the whole setup is laser safety curtains. Because it's a 2500 watt laser, if i didn't have laser safety curtains , the relections/etc could very easily blind someone at a fairly long distance. The NOHD (nominal ocular hazard distance) is something like 10km (2500 watt laser, 0.06mm spot size…

Please provide some more details on your laser welder. Did you import it from China? I want one so bad, but buying them in the USA seems to be 4-5x retail cost in China.

I wouldn't get one from China, no matter what the price is. Money can't buy eyesight, not in this case at least

Re: How I got my laser eye injury

#218

Post by tivert »

b112 wrote: post #47
MeteorMarc wrote: post #4

Earlier quoted context omitted.

Yes, I also dislike the culture in which this can be called a funny story. Such culture will cause more incidents. Worked in a laser lab for 5 years without incident in a time when eye safety goggles were not used for visible light.

If the Germans can joke about it, anyone can. https://www.youtube.com/watch?v=xJ_86lxP36I

This version of Forklift Driver Klaus is much clearer: https://www.youtube.com/watch?v=TJYOkZz6Dck

Re: How I got my laser eye injury

#219

Post by aftbit »

hotsauceror wrote: post #149
ta988 wrote: post #18

Earlier quoted context omitted.

I have seen a drunk employee wrestling with a moving industrial robotic arm trying to "fix it" after having disabled the numerous safeties with screwdrivers. This was at a major car manufacturer plant. Do not underestimate the horrible situations people can put themselves in.

A relative of mine works with assembly-line robots at heavy equipment manufacturers. He told me that while they were calibrating a new robot that was used to move axles for industrial mining dump trucks, a miscalculation caused the robot to fling a 800 lb axle through the air like a marching band baton.

Now that I'd pay to see. If that happened where I worked, I would be so tempted to run the program again with my phone camera out. After telling everyone down-range to get lost of course.

Now would I do it? No... definitely not, as long as the demon on my right shoulder was being quiet that day.

Re: How I got my laser eye injury

#220

Post by scottlamb »

pflenker wrote: post #188
madjam002 wrote: post #175

Earlier quoted context omitted.

One of the things I hate most in tourist hotspots these days are the people selling high powered laser pointers, normally selling them to kids, and they are shining it at their faces, in the faces of others, and at the neighbours. I swear they never used to be so commonplace. Having worked nightclub lighting a long time ago I have a deep appreciation for laser safety haha

When I was ~12 years old one boy pinned me down and another one shone a laser pointer in my eye just for fun. Needless to say, this has been my „bad eye“ ever since (I’m 39 now)

That's terrible, and I'm guessing they faced little if any consequences for it. I'm mad thinking about this, even though I wasn't involved and it was 27 years ago.

I would like to think that people would know today that laser pointers are weapons so this wouldn't happen, and that if it did happen, the schools' zero tolerance policies (the ones that you hear about used to stupidly expel someone for bringing a butter knife to eat their lunch with) would kick in, as school bullies literally damaging your body for life is completely unacceptable.

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