Damaged eyes?

[Quazar]

I have been working professionally with lasers for almost 10 years. Back then, there were no DPSS lasers aroud, just big heavy argons and kryptons. A laser typically weighed 60 lbs, needed a 100lb 3 phase power supply and generated a whole load of heat. They were also fragile and didnt like being moved around much. After all, most were designed to be used in laboratory conditions. OPerating one on top of a scaffold tower in a club full of smoke and haze was never what they were intended to do.

Having spent the equivalent of $5000 on your new toy, you kind of looked after it, the 400 volts @30 amps electricity supply and 2 gallons of water a minute were never a good combination!! Therefore utmost respect, almost to the level of paranoia was given to laser equipment. Admittedly, we used to do the cigarette lighting trick (at arms length), but that was about it.

Unfortunately, with the advent of cheap mass produced DPSS lasers that are available for the cost of a decent torch, much of the respect for what is essentially a piece of industrial equipment has been lost. Nowadays, kids can buy lasers with the money they make for doing a paper round for a few weeks. The laser has become little more than a toy and as such, everyone is "showing off" their latest acquisition without regard for the consequences.

A friend of mine who is also a professional laserist, has a severe eye injury caused by a laser. After sending a 2W argon laser off for regassing, he was checking it over before firing it up. With ion lasers, you need the cathode to warm up for a few seconds before arcing. After regassing, it is essential to have the cathode running for a while longer before the first strike is attempted. My friend was (carelessly) looking into the back of the tube to check the cathode was glowing nicely, when the tube ignited. Unknown to him, the tube had been refitted the wrong way round and he got a 2W argon beam into the eye from about 4" away. This accident happened over 6 years ago and to this day he still has a large black spot in his vision.

Please treat lasers with the utmost respect, they are not toys by any means. Misuse them and they will bite back, hard. You dont get a second chance, its too late. Be warned, play safe.

 

[k00zk0]

Very well written. ^

So I saw an optometrist (EDIT: I think just an optician, but he knew his stuff) and he looked at my retina using some sortof scope and said that he sees no damage. He said he sees the blood vessels, etc and it looks healthy. I still see a little bit of missing vision though. He made an appointment with an opthamologist for me soon and I'll see what happens then.

On a side note, the optometrist had decent english, but didn't know what a laser module was. I told him it was about 170mw of infrared and he was like "so this was a toy of some sort?" I had to explain to him that I am an electronics enthousiast but to avoid embarrasment I didn't tell him it was a laser pointer but a high quality professional one.

Well, he said he normally sees lesions on the retina when it's burns but there was nothing this time. I just hope this goes away.

 

[TorchBoy]

He made an appointment with an opthamologist for me soon and I'll see what happens then.

On a side note, the optometrist had decent english, but didn't know what a laser module was.

That's a worry. I hope your opthalmologist knows what a laser module is. He/she will hopefully know the kind of damage to look for so will be better able to explain what's happening to your retina. Hang in there.

 

[Gazoo]

Hello k00zk0,
Thanks for the update. I too find it very interesting the optometrist didn't know what a laser module is. I am certain your ophthalmologist will know or at least have an understanding of how a laser can damage an eye. Please keep us updated. Glad to know it is getting better.

 

[stephenmadpotato]

Hi all.
The spot i have I noticed has turned translucent purple any idea what this means?

 

[chuck]

So, it's gone from being completely black (basically dead) to seeing at least some color?

I'd say it's in the process of healing. Either that, or your brain is rewiring itself slightly, to correct for the optical error. Either way, it sounds like a good sign.

Did you ever go see an eye doctor? What did he say?

-- Chuck Knight

 

[Gazoo]

Hi all.
The spot i have I noticed has turned translucent purple any idea what this means?

Shortly after it happened you reported seeing a gray spot. If you are now seeing purple and you can see through the purple, I would think it is a good sign. You should still see an eye doctor if you haven't.

 

[siggis]

Hi stephenmadpotato,

please edit you sig. The "green" radiation is as bad as the IR and since it is
the "primary" frequency it's worse because it has more power and is better
focused. To be on the safe side one has to wear goggles blocking out 532nm AND 1064nm.
Telling people to wear "IR BLOCKING GOGGLES" doesn't help.

Actually one should wear safety glasses for everything above 1mW. A close
shot with 5mW can give you permanent damage.

Apart from that I think you got lucky, the purple spot is a good sign, could be
that the red+blue part of your vision is recovering, green might come later
since it got most of the energy, a specialist can tell you what's going on
exactly.

Good Luck, Siggi.

 

[stephenmadpotato]

Actually one should wear safety glasses for everything above 1mW. A close shot with 5mW can give you permanent damage.

I agree with everything else you stated. However the FDA says that it takes about 10-60 seconds of exposure to do damage retinal damage. The FDA is uptight as it is about these lasers

so I doubt they would be incorrect.

 

[siggis]

Hi,

I agree with everything else you stated. However the FDA says that it takes about 10-60 seconds of exposure to do damage retinal damage. The FDA is uptight as it is about these lasers

so I doubt they would be incorrect.

the FDA is not everything. Here in Germany you have to take security measures when operating anything above 1mW. Above 5mW it get's quite strict. It's correct that it is "unlikely" to cause permanent damage with 5mW. Especially since those normal lasers are not that well collimated and getting hit from a few meters distance will give you only temporary problems. But if you do have a 5mW greenie, which put's out actuall 5mW with a well collimated beam and you look right into the thing from a few inches distance you will get a nice little black spot if you don't happen to close you eye quick enough. It might go away after a few weeks/months, might not, depends on the person. There are some people which have problems looking at the dot of a 30mW green laser on the wall, it actually "hurts" their eyes. I case you happen to shine you laser into the spyglass from someone 100m away at night he will have a big problem.

So this is likely the reason why the FDA considers 5mW as "safe". I can do damage under certain circumstances, it will not do damage under most circumstances. Getting damaged by 1mW will be hard and would require intentionally looking into the beam for extended periods of time even using optical instruments.

I any case, a laser is a laser. And with "cheap" laser pointer you have to be especially carefull, specs are not guaranteed. I've been doing stuff with lasers since years and I did get burned by my own stupidity a few times. Luckily only by the HV from the power-supplies and not by the beams.

I personally consider all those cheap green laser-pointers as dangerous. I'm not going to say they should be forbidden, knifes are as dangerous and freely available. BUT one has to treat them with care and respect.

Do yourself a favor and think about this a bit. The reason why this accident happened was disrespect. Saying 5mW is safe is still disrespect. The right approach IMHO is to pay respect to things. Keep playing with lasers but be aware every moment that every one of them can bite you, even the smallest one and you will stay out of trouble.

We've been looking right into 100mW Argon lasers with safety goggles to adjust them. But we made sure to be two people. Made sure that the goggles are working and in place and so on.

Enjoy playing with lasers and don't take anything for granted. The FDA have some so funny ideas about some stuff as have the respective Organisations here in Germany. One thing is legal here the other there, doesn't really tell anything about the dangers of it.

Bye, Siggi.

 

[Lew Fong]

I agree with the post from stephenmadpotato about the time required for damage to occur, per the FDA. The Army just recently completed a study of the usefulness of lasers for combat use, and divided the devices into two categories: "Blinding" lasers, and "Dazzling" lasers. In short, their conclusion is that a laser is considered "dazzling" if it's power output is less than 500 mW.

Their conclusions were based upon data returned from the field in actual combat situations where Coalition forces were using medium to high powered DPSS laser systems mounted on their infantry weapons. The study was prompted by concerns that lasers now in the field might violate the Geneva Conventions outlawing weapons designed to blind an enemy.

The data pertinent to this discussion is that the human blink response, together with other actions taken by the enemy to avoid direct laser exposure to the eyes such as reflexively moving one's head, etc., made permanent eye injury unlikely at any power less than 500 mW @ 532 nm. So the Army classifies those devices as "dazzling" weapons. For a weapon to be considered "blinding" the Army sez it must be at least 500 mW. This is the minimum power level at normal CQB ranges (< 200 yards) that even begins to deliver enough energy to the eye in the 200 milliseconds before the victim blinks or moves to cause permanent damage. Of course, the Army has a vested interest in setting the "blinding" power threshold as high as possible, because it allows them to deploy the weapons legally. But they also are interested in finding the threshold from the standpoint of combat effectiveness...in other words, how high does the power need to be to be useful as a blinding weapon, if need be? This point was the secondary focus of the study, and the Army concluded that <500 mW lasers were essentially useless as blinding weapons under normal circumstances.

The fact is that the mechanism of destruction of macular tissue by laser light is the same as that for popping a balloon: Sufficient energy must be concentrated for a length of time to produce enough heat to cause burning. I find it highly unlikely that anyone could sustain even mild permanent visual impairment with only a few hundred milliseconds of exposure at the 35 mW level with a beam spot approaching 1 mm in diameter. There is simply not enough energy on target long enough to cause permanent damage. That is not to imply any relaxation of the respect one must have for any laser. But the continuing claims made by many of "instantaneous" and "permanent" eye damage at power levels below 50 mW is simply absurd, and factually inaccurate. One would need to stare into a 50 mW beam at the same spot for a few seconds to do any permanent damage. It is nearly impossible for a person to do so, because of the automatic, reflexive response to bright light. Even the FDA recognizes the general safety of lasers of less than 50 mW in power. There has never been a case of permanent eye injury reported in the US with a laser of less than 50 mW output power. Ever.

What may have happened here could be much simpler: All of us have "floaters" in the eye....spots that swim around. We ignore them usually. If you look for them, you can probably find one. Now, if you accidentally flashed yourself and were prone to be a bit paranoid, you might identify one of these floaters as a laser eye injury, especially if the floater happened to lie under the impact zone. Then, as the initial desensitization or "flash blindness" slowly dissipated, the floater could be interpreted by the victim as a vestigial permanent injury. Maybe that's why the doctor couldn't see anything wrong. Even a pinhole in the retina should not have gone undetected during the examination.

Please keep us updated. I hope by now your situation has improved. Best of luck to you,

Lew

 

[TorchBoy]

The study was prompted by concerns that lasers now in the field might violate the Geneva Conventions outlawing weapons designed to blind an enemy.

Yes, the US Army has a vested interest in not wanting to appear to break international law (not that they actually care much for international law) so I wouldn't place a huge amount of faith or weight in their study.

My own red laser pointer was tested at 4mW output with a fresh battery. From the size of its dot I worked out that it's about the same intensity as sunlight over an area about the size of a pupil. (Of course, in dim light the pupil opens, making it more likely that the full laser beam width will enter the eye.) In my reckoning that means that >5mW is not safe for anything more than a fleeting glance. No, it won't be instantaneous, but serious and permanent damage can and will be done at levels much less than the US Army's acknowledged unsafe "blindness" level.

I'm also not convinced that retinas need to be burned to cause permanent damage. Retinas are a whole lot more complex than most people realise. There are more ways to hurt them than frying them.

 

[stephenmadpotato]

Hi,
Thank you all for your input, it is really good to hear everyones point of view. I know what a "floater" is and I know that I am not seeing one. My problem is a permenant (so far) translucent light purple spot in my eye. There has been many cases of eye damage. I enourage all of you to go to this website http://www.mayoclinic.org/news2005-rst/2800.html I just found and it conquers with my 60 second exposure-damage ratio. I also encourage you to go to this website: http://www.drgreene.org/body.cfm?id=21&action=detail&ref=607 and read some of the facts. That website states it could take 10 seconds. I do believe, with the information provided, we could all argue this matter for eternity as this subject is so contradictory.:thinking:
Regards,
Stephen

 

[insaned]

Hi,
Thank you all for your input, it is really good to hear everyones point of view. I know what a "floater" is and I know that I am not seeing one. My problem is a permenant (so far) translucent light purple spot in my eye. There has been many cases of eye damage. I enourage all of you to go to this website http://www.mayoclinic.org/news2005-rst/2800.html I just found and it conquers with my 60 second exposure-damage ratio. I also encourage you to go to this website: http://www.drgreene.org/body.cfm?id=21&action=detail&ref=607 and read some of the facts. That website states it could take 10 seconds. I do believe, with the information provided, we could all argue this matter for eternity as this subject is so contradictory.:thinking:
Regards,
Stephen

You should consider one thing before relying in any "paper" experience. Your own!
Science is contantly changing, so you must not take it written in the paper as it is! You have your own experience, you looked the laser at a few seconds, and something happened! May not be serious, but something it was! And if I were you, definitly, would not want again any uncautious beam in the retina cells!

Also be safe and wear decent protection glasses.

ps- also military engennering is design to reach specific demands! In analogy, a .22LR ammo based pistol used for rim firing, in the point of view of the army is completelly useless in any way. Altough with this caliber, a burgler can break into a familly house and if something goes wrong, kill everyone in it. (less likelly than obviously a 9mm, but the "less likelly" also implies that it is likelly to happen, even in low %. So for the safe side, you need to bee OFF the %)

So, along in your life, always take a conscious view with opinions, even scientific ones, a try to see beyond paper, because they will not certainlly cover everything, because they had a purpose or intent when written that might not match yours!

 

[Lew Fong]

Excellent links, stephenmadpotato! Thank you!

 

[k00zk0]

Alright. I saw an opthamologist, and he looked at the spot and told me that that's what it looks like when people stare at the sun. He saw a redish burn, but very small. He told me its healing (I can see that it is too) but it will leave a small spot. My other eye and brain will compensate..

He gave me 5 sample packs of Vitalux multivitamin, used for age-related macular degeneration, told to take 2 per day:

Each tablet contains:
Beta-Carotene: 12,500 IU (7.5mg)
Vit C: 250 mg
Vit E: 200 IU
Zinc (Gluconate): 40mg
Copper (HVP chelate): 1mg

And, he gave me these drops called Maxidex:

Dexamethasone 0.1%

He told me those may help with the healing.

I hope that info can help someone who maybe cant see a doctor but can get those medications..

 

[Kiessling]

Taking medications without seeing a doctor and getting a proper diagnosis as well as therapy is never a good idea.

 

[chuck]

One of the pills is a vitamin -- probably pretty much harmless, regardless of whether anything is wrong. It's likely impossible to go wrong with this.

The actual medicated drops, however, should definitely be used under the supervision of a doctor -- medicines are not to be fooled around with.

I'm very happy to hear that you eye is getting better...thrilled, in fact! Have a wonderful 4th of July, and CONGRATULATIONS!

-- Chuck Knight

 

[k00zk0]

I'm in Canada

Stephenmadpotato, how's your eye going?

Yes, the first pill is a multivitamin and it's available in more drug stores I believe.

EDITED: Read following posts and do not use the drops unless directed by a doctor.

 

[jefft]

And, he gave me these drops called Maxidex:

Dexamethasone 0.1%

He told me those may help with the healing.

I hope that info can help someone who maybe cant see a doctor but can get those medications..

As for the drops, they are just an anti-inflammatory and they aren't even to be used for anything related to the macula.. they're for the inside of the eyelids, but the doc said that it may work its way back there and help. I would think that signifies that they're pretty damn safe to use when he gives them without a reason. On the dropper it says you can drop as fast as you want it. 2 drops every 30 minutes, or more if inflammation gets worse. I would think it's pretty safe. It's available without prescription too methinks.

Your eye drops are _steroids_, not simple anti-inflammatory drops. Corticosteroid eye drops _have_ to be used with appropriate caution and are not available without a prescription. Improper use can be associated with cataracts and glaucoma and God forbid, you have a secondary corneal infection while using the drops. Say goodbye to your vision. That little fuzzy spot would be welcome in that case. Very dangerous to make medical assumptions and comments in a general forum without the appropriate training to back them up. Good luck with your eyes. Remember, you only have two of them and they don't grow back.