Why so much hate on lasers?

Grix said:

I had a blindspot in the middle of my vision for several months after mirror-bounce hit with only a 30mW greenie.
Also there was a local indicent where someone shone a very powerful laser on a plane that was landing, I think it was 500mW or so. Anyways, the main pilot suffered 70% permanent blindness and the copilot got blindspots, I don't remember how severe.

So basically:

Because people are going blind from lasers.

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Somehow I doubt that. Unless he had a very expensive green laser with a beam expander it's just not likely. Something like a herc 500 with X10DR might be able to do that, but anyone with the cash to buy one probably wouldn't be stupid enough to go shining it at planes. If they were doing it intentionally as a terrorist act then the problem isn't lasers. It's the psycho holding the laser. If lasers were unavailable he'd probably just bring an ak47 to the mall and go on a shooting rampage or something.

A cheapo laser would probably have really bad divergence/low output and flashblind the pilot at worst. Also the culprit would practically need to be right at the end of the runway and would most definitely get caught.

A cheapo laser would probably have really bad divergence/low output and flashblind the pilot at worst. Also the culprit would practically need to be right at the end of the runway and would most definitely get caught.[/QUOTE]

Typical pointer, say 100 mW....

NOHD, the distance at which nasty damage can/surely will occur, 700-1000 feet or more.

CZED, the distance around which you cant complete flight control tasks, are flashblinded, and need time to recover, around 3000 feet.

SZED, the distance your annoyed by the unit, 7000-10,000 feet or more.

Some of the thresholds for these are measured in nanowatts per square centimeter, so it IS important.

Note, just because I posted a typical NOHD, please DO NOT try this with a friend. I've seen 100 mW average power pointers do 180-200 mW, as the internal temperature control/heatsinking is often poor.


If you give me exact numbers, I have commercial software which WILL calculate FAA accepted numbers for a given laser at powers of 100 mW and up.

FAA's required numbers are based on testing done in a simulator with a DPSS green of variable power and divergence, with multiple volunteer pilots.

The calculations used are for scientific and laser show applications, but it applies equally well to a pointer in airspace. Note scientific uses of lasers in airspace include artificial guide stars for adaptive optics in telescopes, and LIDAR for various atmospheric measurements.

And yes, under certain circumstances, a hot pointer could be detected at 10,000-20,000 feet of slant range, and a approved rescue device, with a upcollimated beam, is sold for this purpose. A similar radar guided device is used to warn pilots if they stray into the DC restricted airspace region, it produces weak green and red flashes that scatter off the windshield of the aircraft. Another application is the Navy's proposed laser guidance system for carrier landings, and it only needs a few MILLIWATTS of visible power.

The eye is the best photo sensor ever built, and one that can be produced by really unskilled labor. ( Small Joke)

Granted, in most cases, more irritation is done when pilots rub their eyes after a flash, but it is a serious concern.

Steve

This guy sound like Wes playing his games again.

T_J :wave:I had the SAME thoughts--or some other Banhammered fool.:banned:.

.I hope not.

If so he won't be here long--

If not lets hope he gets with the program asap.

safety is not a joke- especially NOW.

ck my sig for my new laser!!

Hey hey, you got it going!!! No pix???

Mine is still sitting. I've been packing and painting. It'll be around a month before mine is assembled.

Yeah-- I 'got it going'-- 'bribed' another great friend to build it- all I did was put in the 18650 and marvel---waitng for dark to fire up the fogger.

will do a side by side comparison w/ my argons- 27mW SL and 147mW ML , 111mW Red labby, 6X BR-149mWs and 100mW dpss green aixiz labby.

hope the move goes by quickly and w/o much pain-bend yer knees -take yer time old friend.

I hate movin' worse than warts!!

hakzaw

Nothing wrong with having some help with a project. If I didnt have help on mine, I'd still be using my DX 20mW.

This is my 6th move in 12 years. I've got a good moving crew thankfully. I cant really do too much with my back situation.

Thanks for the good words brother. :beer:

LA5ER said:

I personally never heard or known about a kid getting permanently blinded by a laser!

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I personally do know someone who has been permanently blinded (not completely, but a big blind spot) by a laser! It was by a 250mW, and it wasn't temporary... (PWNED)

Captain Dan said:

I don't think anyone has gone permanently blind by a laser, if your eyes get exposed to a high powered laser it's like a flashbang you'll be blind but not forever. It will have to be exposed in your eye for about maybe 30 seconds straight for you to be permanently blind and no one is that stupid to do that.

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NO NO NO. Can't you read? You WILL get permanently blind from lasers, even at very short exposures. Your eye is like a lense and it focuses the beam down to a tiny dot on the retina. OF COURSE it will burn the retina beyond repair.
Stop spreading these dangerous and false claims. You should not be allowed to own a laser.

Captain Dan, you are wrong. You're wrong in every way a person could be wrong. Did you even see my post? That was from a laser hitting an eye for a split second. It doesn't even take more than a millisecond to get a blind spot like that for the rest of your life. If you don't believe me, then why don't you buy a 1 watt blue laser here, look into the beam (just not more than 30 seconds! -_-) and tell us how your eyes feel after that.

sounds like hes basing the blindness idea on the retina burning at the same rate and way as your arm lol. worse even, since my arm tends to burn quicker than that

This discussion is nuts. The research has been done a long time ago:
1. A Submodel for Combat Casualty Assessment of Ocular Injury from Lasers
R. E. Miller, II , 1978
2. Flourecein analysis of rhesus Monkey retina with laser induced keratosis
Proc. roy. Soc. Med. Volume 66 September 1973

Energy densities of 0.4 joules means lights out forever. thats about 400mWx1second.
And yes, I am a doctor. Glasses everyone, keep your laser safe and enjoy the hobby!

Dave

Regarding a pilot, there is a safety story we tell at the lab I work at (truth or not, I'm not sure).

A guy once borrowing a very high powered laser from the lab to trim a tree he couldn't reach - with no thought to the beam that was going into the atmosphere. (It was also a laser that was designed for long range). It hit an airplane's wing, and caused malfunction that forced him to crash land.

It's serious business.

ShaOwned said:

Regarding a pilot, there is a safety story we tell at the lab I work at (truth or not, I'm not sure).

A guy once borrowing a very high powered laser from the lab to trim a tree he couldn't reach - with no thought to the beam that was going into the atmosphere. (It was also a laser that was designed for long range). It hit an airplane's wing, and caused malfunction that forced him to crash land.

It's serious business.

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Give me a break... "to trim a tree"...

We didn't all fall off the Turnip truck today....


Jerry

Hey, they probably got the laser from aliens too. :na:

yeah, right.... Maybe if its a YAL-25 he took home...

Another fun one is to tell a new student or engineer that (Insert name of big laser company here) cuts white bread at high speeds with lasers, we need to learn how they do it, and stick her/him in a lab with a big co2 or YAG. Toss a couple of loaves of discount stale bread on the optical table before you close the door.

Steve