Calling BS on this one.

Laser strike said to give ferry pilot 3rd degree burns on his eyelid | Ars Technica

Third degree burns?!? Unless someone has managed to get the divergence of their 7W+ diode under 0.1mR I gotta call BS on this one. Not that it's a good thing to be lighting up ferries, planes or cars with a laser but the hype in the media is just ridiculous. It's like they're deliberately trying to kill our hobby:yabbmad:

I agree 100%. I have a couple 5+_watt blues that are focusable. It is very difficult to even light a match at the distance described and over a body of water from boat to boat.

Where's the pic of the burnt eyelid?

I don't believe this at all, the physics based on the distances suggested in this article make the claim impossible.

Maybe they meant retina, not eyelid, even still I have serious doubts.

He would have to have a 2 foot wide lens and a tripod with x-y motorized tracking to burn even paper at 350 feet, and that's just the length of the boat.

I would like to see the laser and know the distance, but it appears to be highly unlikely with anything some fool can buy in a HH blue.

I think society doesn't realize how often the news is wrong and report false information. When I was a skydiving instructor and safety officer we had some fatalities over the decade I worked there and part of my job was to speak to the media. They never once reported the incidents correctly. Some were so bad i wondered why they bothered sending out the crew to ask what happened and get the facts. They clearly just made up whatever sounded more gripping and reported THAT as fact. The media pisses me off to no end. Its hard enough having to tell a persons family how and why their loved one is dead, but then they read the medias BS and start thinking foul play or we were covering our asses causing these families additional unnecessary stress and suffering. But hey, as long as they sell more papers and get better ratings who cares, right?

"He does have third-degree burns on his eyelid and his vision is still not quite back at 100 percent."

Not quite back at 100 percent??????? Just think what his vision SHOULD be like lol

It doesn't sound feasible at all. The 3rd degree burn basically means the damage goes as deep as the entire skin layer, which is about all there is in an eyelid.

Practically this would equate to a laser burn so powerful that it chewed through the eyelid, obviously blindin a person permanently.

This would be odd even on any body part. You can certainly get a second degree burn (blister etc) from exposure of skin to a laser beam, but you'd normally get away from that if you could by any means.

Surely you can stick your hand in a 5 watt beam and get burned, but you would not let that last to a 3rd degree burn unless your hand has held in place by something or someone. Practically laser burns to the skin are limited to first degree because people get out of harms way when in starts to hurt, and diode lasers are not powerful enough to cause more severe burns before you can.

The story links to a TV report which shows a picture of the laser used. It appears to be this one, which claims to be a 10 watt, 450 nm, handheld sold for $97 to $110.

Focusable High Power Blue Laser Pointers 10000mw 10w 450nm Burning Match/Dry Wood/Candle/Black/Burn Cigarettes+Glasses+Charger+Gift Box From Haoyunfa88899, $107.86 | Dhgate.Com

Ed

CoherentRays said:

It appears to be this one, which claims to be a 10 watt, 450 nm, handheld sold for $97 to $110.

Click to expand...

Lol

-Alex

Oh well, the media and whatever they come up with without doing any fact checking.

I seriously doubt that anyone could construct a laser that is no larger than say a 6D maglite overall that could cause a skin burn at 1 km distance, especially given a budget of $10.000 to do it.

By overall i mean including any optics - it may be feasible with a few watts of blu(ray) and a telescope, but that would no longer really be a handheld device. I reckon it would require a tripod to keep aim at all, regardless if the whole system was light enough to be 'hand held' at all.

Even if one were to assume the laser was powerful enough... The blink reflex was fast enough to avoid most of the retinal damage of a laser powerful enough to cause third degree burns? Maybe his eyes were already closed when the laser struck? Okay, then why were there burns on ONLY his eyelid?

Nope.

The part of the story regarding burns is complete and utter bullshit. With one notable exception (burning man incident) I don't think I've come across any other story with permanent damage to vision, let alone actual burns.

Was a laser pointed? Yes. The rest is just just sensationalism.

This Is the Laser That Someone Allegedly Pointed at the Captain and Chief Mate of a State Ferry Last Week - Slog - The Stranger

10W... that laser is not.

Oh well, that's the media for you.

Yes that laser can probably light a match - within a couple of meters. Looks like a multimode 445 to me, i think o-like sold something like it for a while. I'd presume it's about half a watt with very poor divergence typical of multimode lasers.

I light cigarettes with similar lasers at point blank range, but there is no way that it could cause a skin burn 100 meters away.

I'm not sure what the distance between the laser and the ferry boat was, but it would seem unlikely that this laser could even exceed MPE limits at a kilometer, although it would be bloody bright to look into.

Ha! 10 W in a handheld battery-operated laser? That's funny. What's more funny, I clicked the link and saw there was another item marked as 20 W in an even smaller host. I suppose you could drive a 440 nm diode to 10 or 20 watts, but with today's diodes, that output would only result from the diode self-destructing over the course of a few (maybe several) microseconds.

Anyway, I've seen internet videos (the best source for true unadulterated information LOL), where a guy put his leg in a 40 W CO2 laser cutter to give himself a "tattoo," and received what appear to be second degree burns at a distance of a couple cm from the laser head. I suppose since we're dealing with completely different wavelengths, it doesn't make much of a point, but, anyway, if he got third degree burns on his eyelids, wouldn't the high intensity light be permanently blinding.

Anyway, the whole discussion is probably just undermining the point that you never point a laser at another person.

Not so HA-HA, Probably not so much BS in this case... The media is wrong, but they have it half-assed correct.

Quote ""burns on the outer coating of the eye and broken blood vessels.""

Its probably a "Secondary Injury", something that you only find mentioned in a few really good laser safety textbooks.

Classic definition of secondary injury: Your climbing a ladder and get flashed by the laser, your startled, and fall off the ladder. Or you trip over something in the lab, and hit your head, because you can't see in the dark because your wearing safety goggles... The laser strike does not have to do damage, but the "Startle" reaction can initiate something else.

In this case, he has probably done what many pilots and other folks have done when flashed with a laser, immediately wipe his eye, violently, with his dirty hand.

Think about it, what would happen if you rapidly wiped your cornea with a sandy, sweaty, glove. Especially one that would have bunker fuel on it from filling the diesel tanks... Or worse, sea salt...

Hardest thing to do with you've been hit in the eye with something physical ,or have gotten a chemical in it, is to stop rubbing your eye.. The eye is very directly tied to the brain. Ask a seasoned paramedic or many parents about practically having to restrain people/children when there is a eye injury or the eye has gotten badly poked.

You rub the eye, and then it gets more irritated, and you rub it some more...

Results: conjunctivitis and friction burns..

It DOES happen..

Trust me on this... It happens more then you think... We actually train for this reaction, when given the brief on eye-wash stations in the chem lab.

Steve

Are you saying that the man possibly received third degree burns from (the friction of) rubbing his eye with a dirty hand?

Also, the quote you gave was in reference to a copilot from another incident, and was not given to pertain directly to the ferry pilot who received "third degree burns on his eyelid" from the laser, according to the article, which, it sounds like we all agree, is, at best, misleading.

I think, more likely, the article is wrong, the product description of the laser is wrong, and the only things that are right for sure are that someone pointed a high powered laser at a boat, that the boat's crew were distracted, and the situation was dangerous. News outlets don't make money telling the whole truth, so they have to twist things. Most of the general US public likely believes that you can go online and buy a death ray laser and then shoot someone with it. These people are more likely to spread buzz about a news story that panders to that, then whatever the actual story is, which is probably something to the effect of "Two drunk guys point a high powered laser at a boat and put a bunch of people in danger, and prove that drunk people and idiots shouldn't play with lasers."

BoostJan,

I think the man received corneal and tissue abrasions from rubbing his eye. Considering the measured NOHD of a 1.1 watt Wicked Lasers blue pointer is ~600-800 feet, I have nothing more to work with as I do not know the exposure distance, exposure time, speed of the vessel, and true divergence in both axis of the "pointer".


Let me throw in a few more things here, based on hanging out around commercial shipping when I was a kid. Plus something often neglected in the simplified view of laser safety, which is "Optically Aided Viewing".

IF he was wearing eye glasses and thus had an effective 50 mm collection aperture, instead of a 7 mm pupil aperture, what he is saying may become somewhat plausible.

If he had binoculars in front of his eyes, the numbers get "believable".

But we can safely assume he irritated his eye rubbing it. It is a common, and I mean common, reaction to laser flashes. The media might have taken a common American Phrase "Rub Burn" and turned it into a "third degree burn".

Anyone who has played baseball or soccer knows sliding abrasions can hurt like hell.


This is the probably the situation as the Delta Airlines pilot, who claimed he had corneal damage from a non- Q-switched green laser.
If you read his statement, he rubbed his eye profusely after the beam hit him.

Which is more plausible, secondary injury or a thermal burn on a small spot of his face from a diverging blue LD? At close range, I'd admit he could easily have a thermal burn and eye damage, but at more then a few hundred feet, something else happened.

Without a doctor's statement, all I can do is speculate, in the hopes that a few LPFers learn about secondary injury and OAV.

After 20+ years in the business, I'll use one of my titles.. Which means I do have some formal education in this area. From what I am reading, I can speculate that you are hearing about an abrasion.

We don't have enough data to reconstruct anything, which is why I said "probably" in my first post.


Steve Roberts, Certified Laser Safety Officer...