Why is it Bright LED lights seem to blind or......

[cslinger]

To me at least, why is it that bright LED lights seem to blind or irratate my eyes much more than more powerful incandescent lights. For example if I shine say a Surefire A2 or SL TL2 into a mirror at my face they obscure my vision but don't really irratate me. If I do the same with say a Surefire KL1 or Inova T1,T2 or T3 it tends to irratate me much more and I am more likely to turn my head away. I realize the T3 is pretty powerful but the KL1 and T1 and T2 are not all that bright in comparison to the Incans I mentioned.

Do LED's flicker at an imperceptible rate or something that causes them to be a bit more irratating to the eye? I have spoken with other folks who seem to agree.

Thanks
Chris

 

[unnerv]

I think it might be a combination of things, like more blue content, and the fact that it get's to full brightness much faster, not allowing as much time for your pupils to close as much.

 

[DimBeam]

I would not make a regular habit of looking at lights through the mirror. Try pointing lights at a wall or a distant tree and it won't hurt as much. /ubbthreads/images/graemlins/wink.gif

 

[MaxaBaker]

LED lumens also comes from a smaller area than high power incans so I think it may have to do with LEDs having a higher surface brightness.

 

[Kryosphinx]

Re: Why is it Bright LED lights seem to blind or..

I notice the same thing. I think it has something to do with the wavelengths in the light. Sort of how red light can preserve your night vision. I also notice how red light doesn't hurt my eyes too bad. And since LED's don't give of red light (I think), and since incans do give off red light, thus the incans would hurt less.
Edited for clarity

 

[Mags]

Re: Why is it Bright LED lights seem to blind or..

Excellent question! Honestly, I dont know. /ubbthreads/images/graemlins/stupid.gif. I do wish someone who knows comes along and explains. It is one of those questions I keep in my mind, but dont bother to try to answer. I just accepted it as a fact, and ignored why. But nevertheless, I would like to know too!

 

[UVvis]

Re: Why is it Bright LED lights seem to blind or..

Red light doesn't exactly preserve your night vision, it just harms it less.

Basically you have three types of cones (Color seeing thing) in your eyes. These are basically red, green, and blue (RGB wow!) detectors. You have less red detectors than the others. Your eye is most sensitive to greens, which is why there are so many shades of green.

The rods in your eye, (Black and white) take a certain amount of light energy to stimulate these. You have more of these in your eye than the color sensitive cells, hopefully.

So basically, a low level of red light is stimulating perhaps 10% of your color sensitive cells, and a portion of your rods depending on intensity.

A blue green light is going to be stimulating perhaps 90% of color sensitive cells, and more of your rods. This is because the lower wavelength EM packs more energy than higher wavelengths (planks's times speed of light over lambda). So it takes less high energy particles to do the same work as many lower energy particles.

So when you have a LED putting out something near UV and the phosphor giving off more higher energy particles, you can stimulate more of the eye quickly. The same amount of energy in red vs blue green light will have the blue green causing more reaction as you are stimulating more of the eye than with red (which isn't going to stimulate blue green cells).

This is basically a simplified version off the top of my head. I might have some of it wrong.

What I am most amused by is discussions of "white" light. This to me depends on what you want white to be, and equal amount of energy of all wavelengths, a spectrum that matches our sun's output per wavelength (which incan's do better than most LED's), or what one individual call's white.

 

[cheapo]

Re: Why is it Bright LED lights seem to blind or..

hmmm, tl2 LED, is it good for throw?

-David

 

[cslinger]

Re: Why is it Bright LED lights seem to blind or..

Sorry my TL2 is actually an incan. I was just saying that it is very bright, much brighter by all rights then say my E1L but that little E1L will hurt your eyes.

 

[Roy]

Re: Why is it Bright LED lights seem to blind or..

Probably has to do with the light off an led is almost monochromatic so almos all of the light energy is concentrated in a very narrow bit of spectrum. I once had a blue-green MadMax LS that seemed so bright to my eyes that the reflection off of a white object would hurt my eyes.

 

[Donovan]

Re: Why is it Bright LED lights seem to blind or..

Yeah, I noticed the same thing! Even low power LED's like keychain lights or other bright single LED lights seem to irritate my eyes much more than even my high power incans do. My cat is terrified of the light that a small 1AAA Dorcy puts out, but just looks away when I shine a MaxFire LX at him!

 

[chrisse242]

Re: Why is it Bright LED lights seem to blind or..

I guess it's the same effect that makes HID-headlights in cars so annoying. When Mercedes and BMW started using them in germany, people started complaining about how they felt blinded when looking into those lights from an upcoming car. Personally I got used to it, but I still feel a difference when a hid and non-hid car are passing by. So I think it's the blueish colour of the light that is responsible for this effect.
The funny thing is how manufacturers keep insisting that their lights are not blinding anyone.

Chrisse

 

[CPFMan]

Re: Why is it Bright LED lights seem to blind or..

Good news indeed. More iritating than incandes. Now your leds are a more potent weapon. /ubbthreads/images/graemlins/str.gif

 

[Donovan]

Re: Why is it Bright LED lights seem to blind or..

Someone was asking about a light for defense in another thread... Even though LED's are nowhere near as bright as high power incan's, I wonder if they would be more effective?

 

[Donovan]

Re: Why is it Bright LED lights seem to blind or..

[ QUOTE ]
chrisse242 said:
I guess it's the same effect that makes HID-headlights in cars so annoying. When Mercedes and BMW started using them in germany, people started complaining about how they felt blinded when looking into those lights from an upcoming car. Personally I got used to it, but I still feel a difference when a hid and non-hid car are passing by. So I think it's the blueish colour of the light that is responsible for this effect.
The funny thing is how manufacturers keep insisting that their lights are not blinding anyone.

Chrisse

[/ QUOTE ]

Whats MUCH more annoying are those fake "HID look" bulbs some people put in their cars. Those are much more irritating to my eyes than real HID...

 

[UnknownVT]

preserving night vision

[ QUOTE ]
UVvis said: Red light doesn't exactly preserve your night vision, it just harms it less.

[/ QUOTE ]

Sorry to stray off topic -
but Red, longer than about 650nm will and does preserve human Scotopic night vision -
please see this reference thread:

Human Night Vision Preservation

Red is well documented and supported by authorities on the subject - where human scotopic night vision is critical - like the military -

USAF Flight Surgeon's Guide: Chapter 8
(about 2/3 down the page under the heading "Night Vision")

 

[IsaacHayes]

Re: preserving night vision

I agree LEDS seem brighter more irritating when viewed DIRECTLY. But I disagree about HID. For some reason it seems less irritating, and more soothing than an intense yellow beam shining in all directions at me. Plus the HID in factory vehicles have a vertical cut off so it doesn't shine high up.

 

[MaxaBaker]

Re: preserving night vision

I definitly think it's easier to look at HID than incans (high power ones that is). Although a Havis-shields light puts out more light than a Husky spot, it hurts more to look into the husky. I think the heat that incans give off also has something to do with it.

 

[UVvis]

Re: preserving night vision

Also,

Some colors are more mentally soothing than others, like pinks in some supermarkets, hospitals, and places. Most LED's do not put out spectra that are as mentally soothing. As vision is physical response plus mental interpretation.

UknownVT, I'll send you a PM to discuss this more offline. I'm intrigued.