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Is visible light dangerous? Watch

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    If you're hiding it can be fatal.
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    When EM waves interact with matter, a small amount of heat may be produced.
    However the light itself is not dangerous, it's the effect it can have on other things which is (actually if I remember correctly when it interacts it raises electrons to a higher shell and when they return to the ground state they release IR radiation, or any other wavelength depending on the exact conditions)

    When you look at the sun, you're not just looking at a light source, you're looking at a heat source - the IR rays being focused onto your retina is what burns your eyes out. A medical physicist might be able to say if something happens when too much visible light enters your eyes but I doubt it - I reckon it'll be the heat that does the damage (either IR rays entering the eye, or visible light interacting with parts of the eye to produce heat).

    So to sum up, yes, but only indirectly.

    Don't quote me on that though - I'm only a physics undergrad, I don't know everything!
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    Why's everyone mentioning UV or Infrared? It's in a completely different part of the EM spectrum...

    And yes, it can be damaging; to your eyes, if it's highly concentrated, and closer to the "purple" part of the VL spectrum.

    I.e. Lots of "purple" photons passing through an area, in a certain time.

    I.e. Very large \frac{N}{A \delta t}
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    (Original post by ImScaredOfFil)
    http://www.ehow.com/how-does_5220937...age-eyes_.html

    Explanation of why looking at the sun is damaging, its all down to UV. Laser's will be the same I reckon
    lasers would not be the same because they only emit at a certain narrow frequency i.e red or blue etc. its more that you just physically break down your retina cells at the back of your eye if you look at a laser.
 
 
 
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