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Registered Member #99
Joined: Thu Feb 09 2006, 06:10PM
Location: florida, usa
Posts: 637
Eric wrote ...
$77 is a very good deal. I'm sure you could sell it for twice that if you wait a little.
I don't like the whole close your eyes thing... Just one mistake and things could suck a lot. I just know I'd be the one to do it too. (<--that's me with no eyesight)
Yup, i am building a much more powerful PFN for it right now...It will have a 88uF 1200volt oil filled capacitor, a suitable inductor, and a small Power supply for charging. A grill ignitor triggers it right now, but i pan to build a trigger circuit later for it.
I may end up selling it later, as my GF doesnt like it But not after plenty of pictures!
Registered Member #75
Joined: Thu Feb 09 2006, 09:30AM
Location: Montana, USA
Posts: 711
I dont know where this misconception comes from that any laser will instantly blind you if it hits your eyes. Actually causing an explosion big enough to fuck up your entire retina requires a couple of joules of pulse engery, and I have seen very few amateur lasers capable of doing that. The far more common mJ pulses will just erase a tiny bit of your retina, and leave you with a pinhole-sized black spot. Incidentially the retina is far from perfect as it is anyway, and the brain does a great deal of image reconstruction based on the crappy information it gets from the retina. So you really have to blow big chunks out of your retina before your sight gets noticably worse. If it was so easy to blind people with lasers, terrorist would be doing that all over the world, think about it. I have seen laser labs with a bunch of multi-watt lasers running and not a single person bothering to wear goggles.
This is not to say that lasers are not dangerous, by all means, they are, but I don't like this "dont play with matches" attitude, and I think you should know what you are doing. And with flashlamp pumped lasers, electrocution is by far the greatest hazard.
Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
Well, it's by no means true that any laser will instantly blind you. But, some lasers will, so it pays to be careful with them. You should read the appropriate laser safety information for the type and power level of laser you are working with. Invisible beams are especially bad because your blink reflex doesn't work. Any wannabee laser experimenter should read Sam's Laser FAQ, especially the safety section. If you can't be bothered then check this out
I work for a company that makes low-powered laser equipment. I casually wave around He-Ne and red diode lasers of a few milliwatts, but I get a little worried around our 150mW 980nm pump lasers. I believe they are pretty harmless to the eye since the beam is uncollimated and diverges very steeply on exit from the fibre, but the fibre end will burn holes in anything black
Registered Member #99
Joined: Thu Feb 09 2006, 06:10PM
Location: florida, usa
Posts: 637
Here is my laser. I set it up on a baord with PSU and all...Triggering is via grill ignitor... The capacitor is HUGE...weighs 8lbs and is about 9in tall...88uF 1200volt oil filled...
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Nd:Yag Lasers or your own Lasers
(<--that's me with no eyesight)
But not after plenty of pictures!
