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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

#241

Post by jrockway »

meindnoch wrote: post #173
cowthulhu wrote: post #164

Earlier quoted context omitted.

Are lasers typically able to reflect off of surfaces that diffuse light (ie drywall)? I’m totally ignorant when it comes to laser safety, apologies if this is a stupid question .

Do you see a bright spot when aiming the laser at drywall? If the answer is yes, then laser light is being reflected into your eye. Hope this helps!

> Do you see a bright spot when aiming the laser at drywall?

It was red for a second but now what appears to be a black hole is consuming everything.

Re: How I got my laser eye injury

#242

Post by franciscop »

bongodongobob wrote: post #228
franciscop wrote: post #111

I've touched all sorts of things in my "Maker" years, but one of the things I'm never going to touch by far is lasers. I know how bad they are, and I also know how woeful unqualified I'm for messing with lasers. Heck, I've even left a couple of dancefloors in clubs that I heavily suspected were firing actual lasers at the people, wonder how many of those were actual lasers vs light pointers and how many people got un…

They are actual lasers and they're fine. Assuming you're talking about the light shows and not just random people.

I mean the light shows. Why do you say they are fine? It'd depend on who sets it up, right? If it's professionals I'd be a bit less worried, but in my country and many others def-not-professionals handle things that they shouldn't be handling, including setting up official shows.

Re: How I got my laser eye injury

#243

Post by jrockway »

DannyBee wrote: post #50
RealityVoid wrote: post #27

Earlier quoted context omitted.

I'm dying of curiosity how cheap a cheap laser welder can be.

So, to clarify - what i have is a very nice IPG lightweld 1500 XR. They are normally not cheap (30k), and are very nice and well thought out safety wise. One of the fun parts when i lived in the bay area was that as companies got acquired, they didn't know what to do with the stuff they had before acquisition that isn't needed anymore, and it either sits in a warehouse, or gets auctioned off (or both!) So for example…

> They already had plenty of VMC's in the machine shop, etc, and didn't need these, and it was not worth the trouble to sell them. At least back then.

Darn, we were trying to get a mill for the NYC office's makerspace. It was probably a safety issue and not a parts procurement issue, though.

Re: How I got my laser eye injury

#244

Post by gumby »

robertlagrant wrote: post #197
gumby wrote: post #139

Earlier quoted context omitted.

> I was in the Marine Corps and every time we got to test some new piece of gear the safety officer was like "No, you can't live fire... I thought the whole point of the Marines was to cause maximal amounts of damage. Are you implying there is a constraint on that? But now I understand why the marines hate the navy: I had a buddy who'd been in the navy and he said they kept the kids busy by cleaning and painting ever…

> But now I understand why the marines hate the navy: I had a buddy who'd been in the navy and he said they kept the kids busy by cleaning and painting everything but frequently they'd let 'em blow off steam by tossing cardboard boxes and stuff off the end the flight deck and shooting at them with the 50 cal machine guns. If anything this should be why the taxpayer doesn't like the navy.

I’ve always assumed this kind of stuff is cheaper than the damage they’d cause if they were idle.

Re: How I got my laser eye injury

#245

Post by ChrisMarshallNY »

trelane wrote: post #91
RandomThoughts3 wrote: post #87

Earlier quoted context omitted.

I may or may not be aware of hull damage being caused or not caused by a rifle being fired from the flight deck of a ship. My point being, your safety officer had a point.

I think they know that. I read their comment as sarcastic.

OK, you have a bunch of kids, who, under different circumstances, might be playing grabass on campus, instead, are in charge of incredibly deadly stuff.

What could possibly go wrong?

Re: How I got my laser eye injury

#247

Post by cwillu »

oh_my_goodness wrote: post #224
tlb wrote: post #100

Earlier quoted context omitted.

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.

If it's a 1-micron wavelength laser with a 60 micron radius spot, the divergence can't be much less than about 5.7 mrad half angle. What makes eye safety tricky is just that 2.5 million milliwatts is a lot of power. Even when you spread it out some.

‹twitches in metric prefix›

2.5 kilowatts. It's called 2.5 kilowatts.

‹calms down›

2.5 kilowatts is how much power a tea kettle in the UK draws. It's an insane amount of power to pump into a 60 micron point.

Re: How I got my laser eye injury

#248

Post by oh_my_goodness »

cwillu wrote: post #247
oh_my_goodness wrote: post #224

Earlier quoted context omitted.

If it's a 1-micron wavelength laser with a 60 micron radius spot, the divergence can't be much less than about 5.7 mrad half angle. What makes eye safety tricky is just that 2.5 million milliwatts is a lot of power. Even when you spread it out some.

‹twitches in metric prefix› 2.5 kilowatts. It's called 2.5 kilowatts. ‹calms down› 2.5 kilowatts is how much power a tea kettle in the UK draws. It's an insane amount of power to pump into a 60 micron point.

2.5 billion microwatts.

Re: How I got my laser eye injury

#249

Post by sebastiennight »

cwillu wrote: post #247
oh_my_goodness wrote: post #224

Earlier quoted context omitted.

If it's a 1-micron wavelength laser with a 60 micron radius spot, the divergence can't be much less than about 5.7 mrad half angle. What makes eye safety tricky is just that 2.5 million milliwatts is a lot of power. Even when you spread it out some.

‹twitches in metric prefix› 2.5 kilowatts. It's called 2.5 kilowatts. ‹calms down› 2.5 kilowatts is how much power a tea kettle in the UK draws. It's an insane amount of power to pump into a 60 micron point.

This seemed like a wild claim (2500 watts for a tea kettle!? As much as a microwave oven in full blast?) so I looked it up. Wow.

Re: How I got my laser eye injury

#250

Post by porknubbins »

sebastiennight wrote: post #249
cwillu wrote: post #247

Earlier quoted context omitted.

‹twitches in metric prefix› 2.5 kilowatts. It's called 2.5 kilowatts. ‹calms down› 2.5 kilowatts is how much power a tea kettle in the UK draws. It's an insane amount of power to pump into a 60 micron point.

This seemed like a wild claim (2500 watts for a tea kettle!? As much as a microwave oven in full blast?) so I looked it up. Wow.

Brits don’t mess around with tea I guess. I believe they’re mostly on 240v even for residential there. Correct me if I’m wrong but I don’t think it would even be possible to heat water that fast in the US on 120v.
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