Around these parts we like bright lights..
We have all had that moment “Ahhh!!! The flashlight got in my eyes!!!”
And we have definitely told our kids not to look in the sun or our crazy bright flashlights…
And there is a whole group of lights designed for combat situations called tactical lights. Most military or law enforcement would never go without one.
Lets get into the facts and different conditions…
Can I get eye damage from bright lights?
The answer here is a clear YES!
From Bright Focus a non-profit with one of its focuses being Macular Degeneration we learn that studies have been done in mice that show that light with the same intensity as the sun can cause retinal damage in a very quick amount of time.
There have also been studies that show that long term exposure to light not that bright can cause permanent damage. It is believed that the retina becomes overloaded and creates molecules that make it over-reactive.
From the American Academy Of Ophthalmology we found a specific question asking “Can a flashlight harm your eyes?” In this article, a doctor answered that “Light from a standard flashlight cannot cause ocular damage.” later it is stated that laser pointers can.
It needs to be noted that this question was answered in 2013 and if we look at somebody like Fenix flashlights their brightest light at that time was 3500 Lumens.
Now it is 12000 Lumens… And there are flashlights with over 100,000 Lumens right now.
Truly Lumens is not the right measurement to use here since it is total light output as opposed to amount of light in a specific direction. This is called Candela or in the old days was called Candlepower. For more on this check out our article on converting from lumens to candlepower.
So in 2013 the same Fenix flashlight was 126,000cd and the highest Candela current light from Fenix is 213,000cd.
And there are flashlights with over 1,200,000cd…
We were not able to find a figure that mentioned the Candela of a laser pointer in 2013.
To take this one step further we are going to move from Candela to Lux since lux has to do with how much of the light actually shines on a target.
According to Wikipedia the lux of direct sunlight can be upto 100,000 but as low as 32,000 depending on where it is in the sky. This is a number per square meter. And is a reading of how much light actually gets to that square meter so distance is a factor.
The formula for Candela to Lux in meter is: Lux = Candela/(distance)^2
So at 1 meter the old fenix light at 1 meter still has more lux than the sun if it is 1 meter away 126,000lx.
At 10 meters the old fenix has Lux = 126,000/(10)^2 which is 126,000/100 = 1,260lx.
At 5 meter the 1,200,000cd light still has 48,000lx which is still in the sun range.
The one caveat here is that the sun rays do include UV light and other wavelengths that might do the damage but on a pure brightness level if the sun can damage your eyes due to brightness so can these lights.
It is likely even higher than the most recent lights but our point is that we can not take this 2013 eye damage statement as true since there have been so many advances.
What is flash blindness?
The best way to describe flash blindness is when you are taking pictures with a camera, and the flash goes off and temporarily blinds you.
This most frequently happens in portrait studies as their flashes are more powerful than those found on ordinary cameras or phones. This same thing can happen with brighter flashlights when they are shone directly in the eyes.
How flash blindness occurs is the light temporarily bleaches the retinal pigment. Once the bleaching wears off, and the pigment goes back to its normal color, you can see again. At most, the bleaching takes a few minutes to wear off.
The only time it lasts longer is when you are in the dark because your pupils are more restricted and open already.
Can a Flashlight Permanently Blind You?
The short and simple answer is that no flashlight has ever been reported that permanently blind someone, but it can cause some temporary side effects and damage to your vision.
While no light has been recorded to cause permanent blindness, that doesn’t mean they don’t create other vision problems. When a light is shined directly in somebody’s eyes, there are temporary effects to deal with. Some of the more common effects are temporary blindness, seeing dots, and mental confusion.
In extreme cases, a lesion may form of the retina temporarily. In most cases, these temporary effects go away in a few seconds, but it’s always good to be careful when shining flashlights directly in somebody else’s eyes.
Does Eye Color Make a Difference?
It could, eye color doesn’t make a difference in terms of blinding people as flashlights haven’t been reported to blind anyone.
Eye color does create some important differences because lighter colored eyes are more sensitive to lights. People with light-colored eyes already take extra precautions with sunlight, and flashlights are no different.
There is a higher risk of damage occurring to those with lighter colored eyes than darker colored ones with constant exposure to bright lights directly in the eyes. People with light eyes generally have to be more careful with a brighter light than those with darker eyes, but both should take precautions for prolonged exposure.
Short exposure, such as a light briefly shining into your eyes, probably makes no difference with eye color. Both light and dark colored eyes will see spots or suffer from temporary blindness for as long as a few minutes. Once the temporary effects are over, your vision goes back to normal.
Use Temporary Light Blindness For Self Defense
Many people look to a flashlight as a form of self-defense because they are under the impression it will blind their attacker. This is true to a point, as it only causes temporary blindness if the light is bright enough to prevent your attacker from seeing anything as they advance towards.
So you can run away or hit them while they are disoriented. For this reason lights are great non-lethal self defense tool.
This is also why police always have a bright duty light with them, they can easily find and disorient a suspect.
Something else to consider with shining lights into people’s eyes is the disorienting effect it can have on you. Especially in a small space where the light can bounce off of a wall and have the same temporary effects on you.
Some other effects that have been reported from light is, strobe lights often cause confusion in people, as well as nausea. Seizures have also been linked to strobe lights. With all this in mind, it’s best to avoid shining lights directly into your eyes whenever possible.
Conclusion
Flashlights are probably not going to blind you, and the chance of lights doing any permanent damage is low. Even the brighter lights have a low risk of causing eye damage since prolonged and constant exposure to high power light in the eyes is what causes permanent negative effects on a persons vision.
Flashlights aren’t the primary source of eye damage, it’s more lasers, flashes, and the sun that create the most problems.
Thanks for visiting the site. Hope you found what you were looking for here. Feel free to look around at our other light focused articles and if you are looking for a flashlight jump over to our overall light round up guide.