# ever looked into the light beam of a bright flashlight by accident?



## mccririck (May 18, 2013)

I did with a 400lm flashlight at work, I accidentally turning it towards my eyes when it was switched on. It made a weird burn line that I could still see when I closed my eyes. Are there any stories of people causing permanent eye damage with flashlights?


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## Showmethelight (May 18, 2013)

Lol, by accident yes, but as a flasholic, more times on purpose because I'm dumb. Very tempting to look at the light, not sure why, at least for me. No, I haven't looked at solar eclipses or the sun for long periods.

i do wonder what lumen mark might become harmful to eyes though, I can testify anything under about 2000 has no lasting damage lol. Jokes aside I'm much more careful with my lasers and would never play around with them.


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## melty (May 19, 2013)

Are you forgetting what forum you're on? _Everyone_ here has looked into a powerful light on purpose (or on "accident"). I don't think leds have yet reached the intensity at which "accidental" exposure could cause permanent eye damage.


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## StarHalo (May 19, 2013)

Gotta ask the laser guys about permanent damage, flashlights will only temporarily blind you. Remember that streetlights are ~40,000 lumens, and you see those all the time.

The bigger concern is chip weevils..


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## jorn (May 19, 2013)

It's the intensity of the light (lux or cd) that will hurt your eyes, not the lumens. I can stare all day at my ~ 1000 lumen lightbulb in my livingroom. but i cant stare at a 100000 lux flashlight for long


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## bluemax_1 (May 19, 2013)

jorn said:


> It's the intensity of the light (lux or cd) that will hurt your eyes, not the lumens. I can stare all day at my ~ 1000 lumen lightbulb in my livingroom. but i cant stare at a 100000 lux flashlight for long



Exactly.

The intensity matters more than the total output. For what it's worth, in testing flashlights for their effectiveness in temporarily impairing vision in lower light environments, lights with hotspots in the 20,000 - 30,000 candela range appear to be the sweetspot from distances from 6-30 feet. Once the lights get above the 40,000-50,000 cd range, they're actually painful to get flashed in the face/eyes with. Obviously, the closer the range, the greater the intensity as well. Even lights with lower intensities though, can leave a temporary afterimage in your vision (especially if your pupils were dilated from dark adaptation) for up to several minutes.

I'm not sure what intensity levels start becoming dangerous though. I'd imagine someone holding your eyelids open and shining a 100,000 cd light into your eye from 6" away probably isn't healthy for your eyesight. Fortunately, the instinctive response to a bright light in your face is to close your eyes, turn away and/or raise a hand to shield your eyes from the light. As far as how much light it takes to cause instantaneous damage, I know looking at a nuclear blast without eye protection can do it. No idea what the intensity hitting the retina is though.


Max


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## AnAppleSnail (May 19, 2013)

Flashlights often reveal existing eye damage, but usually won't cause it without secondary optics (focusing a 1000 lumen light so all the light hits your retina would be about 3W. This would require careful planning and difficult equipment.


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## jorn (May 19, 2013)

It's not healty to stare at the sun. Direct sunlight is somewhere between 32000-130000 lux and we got throwers that are more intense than 130K. lux. But i dont know if it's the uv rays or the intensity of the sun that makes it bad for the eyes. If you watch someone welding, it's the same thing. Bright, lots of uv radiation, and it will give your eyes a really good "sunburn" if you watch it too long.


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## kj2 (May 19, 2013)

Happened to me multiple times. And will happen to me as long I've flashlights


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## pikachu_chiu (May 19, 2013)

Always tempted to look at them when turned on, especially after a new purchase:devil:.......


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## Swede74 (May 19, 2013)

It has happened to me a few times, but I try to avoid it. I don't think a few tenths of a second every now and again is likely to cause anything worse than temporary discomfort, but as in so many other areas of life, it is better to be safe than sorry. It seems the brain is very good at "filling in the blanks", so perhaps it is possible to sustain a minor eye injury and not be aware of it because your brain compensates for blind spots, creating the appearance of an unimpaired vision. Self-deception at its best


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## Echo63 (May 23, 2013)

Yes, by "accident"
i have accidentally done it, done it on purpose too

the worst was my new (at the time) Thor i had taken to work
the guys and i were shining it around an oval, when one of the guys turned round to talk to us, and managed to catch me in the beam.
Not much fun experiencing a few thousand lumens in a nice big reflector with dark adapted eyes - instant headache and spots that took 15 mins to go away - i dont think my night vision recovered for a few hours either


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## Mattaus (May 23, 2013)

All the time and only because I'm too stupid/lazy to set up a better test rig :/

Sent from my Galaxy Nexus using Tapatalk 2


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## andurilgc (May 24, 2013)

It's inevitable. That's why, like my pocketknife EDC's the lights are out of reach of the kids

Even a 14500 light on max output in a darkened room is a lot and kids will always look down the barrel then turn something on


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## jaycyu (May 24, 2013)

1500 people viewed this thread. How many of them tried it after reading this > <"
Flashaholics are hopeless 

I had a dead pixel in my right eye for a few years. It was either from oxy welding in my metal-work class or from looking at the sun with a telephoto lens. 
I haven't notice any damage dealt by my 1200-1500 lumen lights. Maybe I should do a run-time test to make sure


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## Mattaus (May 24, 2013)

The number of times I've done the old "I wonder if this will wor....argh!" I couldn't count on all my hands and feet Lol.

Sent from my Galaxy Nexus using Tapatalk 2


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## Stereodude (May 25, 2013)

We'll need to keep you all away from the Nightsword project being worked on in the Spotlights and HID Flashlights subforum. It's reported to be capable of causing instant permanent blindness.


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## dc38 (May 25, 2013)

Stereodude said:


> We'll need to keep you all away from the Nightsword project being worked on in CPF's Custom & Modified Flashlights subforum. It's reported to be capable of causing instant permanent blindness.



Also from saablusters deft x...


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## greatscoot (May 25, 2013)

Like many things there are those of us who have and those of us who will. It is inevitable.


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## FartLighter (May 26, 2013)

Yes, I seem to have tremendously less respect for flashlights than I do for other directional tools.

That is why I cannot bring myself to own a high mW laser... Just not worth the risk, no matter how cool.


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## hikingman (Jul 14, 2013)

dc38 said:


> Also from saablusters deft x...



As perhaps the very first actual holder of a Deft-X, I have avoided any temptations, except turned all the way down to lowest of 6 levels. However, a friend of mine, who is a metal sculpter and uses a welder, walked several hundred feet down the street from me at 6pm a couple weeks ago (so it was very bright out) and I aimed the light square at him on high. He had to quickly shield his eyes and when he got back to me, said it was very similar to seeing an arc welder close up.

Dave


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## mhanlen (Jul 15, 2013)

Actually on purpose several times.


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## NitecoreFan (Jul 23, 2013)

Showmethelight said:


> Lol, by accident yes, but as a flasholic, more times on purpose because I'm dumb. Very tempting to look at the light, not sure why, at least for me. No, I haven't looked at solar eclipses or the sun for long periods.
> 
> i do wonder what lumen mark might become harmful to eyes though, I can testify anything under about 2000 has no lasting damage lol. Jokes aside I'm much more careful with my lasers and would never play around with them.



I just bought a nitecore SRT7 960lm and looked into it on full and strobe and its bright alright. Like you said its so tempting ive had other lights 50-280lm wasnt so bad


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## Cataract (Jul 24, 2013)

Can't believe I never posted in this thread. Yes, I have both on purpose and by accident. The stupidest was looking into my TK40 just for a flash. It hurt for 2 hours.

To answer the OP's question: I doubt we could cause permanent damage with flashlights that barely emit any UV's. The DEFT and high powered HID's might do it, but I still haven't seen a claim about permanent damage, possibly because people know better. I have blinded myself multiple times, I have read multiple posts about people blinding themselves or other people and still no report of permanent damage. (hopefully no one went permanently blind and could not report back) I'm not saying we should look into bright flashlights, our eyes do hurt for a reason, but I wouldn't worry too much about eyesight artefacts during the first hour after exposure.


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## Obijuan Kenobe (Jul 24, 2013)

You must know...too much light will permanently damage your eyes. Why else would a visible laser be dangerous??

Looking directly into an aspheric beam could damage your eyes easily I'd bet.

Don't be foolish. The brightest lights on CPF are not toys.

obi


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## georget98 (Jul 25, 2013)

It took me 5 minutes to learn the interface to my Zebralight SC52 and 2 hours for my eyes to stop hurting. It seemed much easier to turn it on high than low.


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