Brightness damage vs Burning damage

[Redfeast]

Heres what I want to know....
Green lasers are the brightest lasers to the human eye.
IR lasers cannot be seen by the human eye.

If I shined a 200 mw Green laser at a white wall and looked at it close range, the brightness would hurt my eye (I mean the physical pain you feel from a light that is too bright)
However, if I repeated the same experiment, using a 200 mw IR laser, I would not feel the pain from the brightness, but it would still damage my eye.
Is the brightness damage (caused by the green) something different from the burning damage (caused by both)?

What exactly is being damaged from looking at a bright light?
What exactly is being damaged from a high powered invisible laser?

Thanks

 

[daguin]

Heres what I want to know....
Green lasers are the brightest lasers to the human eye.
IR lasers cannot be seen by the human eye.
If I shined a 200 mw Green laser at a white wall and looked at it close range, the brightness would hurt my eye (I mean the physical pain you feel from a light that is too bright)
However, if I repeated the same experiment, using a 200 mw IR laser, I would not feel the pain from the brightness, but it would still damage my eye.
Is the brightness damage (caused by the green) something different from the burning damage (caused by both)?
What exactly is being damaged from looking at a bright light?
What exactly is being damaged from a high powered invisible laser?
Thanks

There is really no difference between "brightness" damage and "burning" damage when thinking about lasers.  Wattage is a measure of ENERGY.  200mW of green is the same as 200mW of IR or 200mW of UV.

The "pain" you feel when you see a bright light is NOT from anything burning.   It is caused by the muscles in the eye and surrounding the eye tightening up very quickly trying to shut out the light.  You cannot "feel" laser light burning your retina.

The damage in the eye from laser light is in the retina and the optic nerve.  When the laser light is focused on the retina the energy transferred to the nerve ending causes them to die.  You end up with a blind "spot."  The brain can adapt and adjust for some small burns of this type.  If you get enough of these, your eyesight will degrade.  

If the light is focused on the optic nerve itself, the optic nerve dies.  In this case you are completely blind.

Bottom line  --  It doesn't matter what "color" the light is.  It is the energy that matters

Peace,
dave

 

[Redfeast]

that clears some things up.
(not that I'm going to be doing this or anything....)

Thanks alot

 

[mikeeey]

[quote author=Redfeast link=1235070780/0#0 date=1235070779]
Bottom line  --  It doesn't matter what "color" the light is.  It is the energy that matters

Peace,
dave

How about a 200mW green versus a 200mW Red? you can see red light, but green is still brighter. Does it appear not as bright as green just because it's closer to IR?

 

[daguin]

[quote author=daguin link=1235070780/0#1 date=1235071560][quote author=Redfeast link=1235070780/0#0 date=1235070779]
Bottom line  --  It doesn't matter what "color" the light is.  It is the energy that matters
Peace,
dave

How about a 200mW green versus a 200mW Red? you can see red light, but green is still brighter. Does it appear not as bright as green just because it's closer to IR?[/quote]

Our eye just "see" green better/easier.  The energy is the same.

Our vision is NOT an "on or off" system. We perceive the green area of radiation the best. It gradually decreases as we go toward the "ends" (UV and/or IR). Somebody will post a graph. I don't have a copy of it.

Peace,
dave