1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help! Why can't we see ultra-violet light?

  1. Sep 2, 2007 #1
    Help! Why can't we see ultra-violet light??

    1. The problem statement, all variables and given/known data

    Can someone please tell me in a nutshell why we can't see ultra-violet light??

    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Sep 2, 2007 #2
    Most of the light emitted by the sun is what now for us is 'visible light'. Our eyes evolved to become sensitive for a range of light in which the sun emits the most. Ultra-violet is emitted far less by the sun than visible light, so it would not be that useful to be able to see this.
     
  4. Sep 2, 2007 #3

    Astronuc

    User Avatar

    Staff: Mentor

    The eyes adapted to light in the 'visible' range. The cones react to particular color, and the optics of the lens do not favor UV.

    http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html
    http://en.wikipedia.org/wiki/Cone_cell
    http://en.wikipedia.org/wiki/Rod_cell

    http://hyperphysics.phy-astr.gsu.edu/hbase/vision/visioncon.html#c1


    The other factor is the UV is generally absorbed rather than reflected. Bees and perhaps some other insects are sensitive to UV and certain flowers do reflect low frequency UV. So as da_willem mentioned, it is more beneficial for eyes to adapt to frequencies with more intensity.

    http://hyperphysics.phy-astr.gsu.edu/hbase/vision/solirrad.html#c1
    http://hyperphysics.phy-astr.gsu.edu/hbase/ems3.html#c3
     
  5. Sep 2, 2007 #4

    DaveC426913

    User Avatar
    Gold Member

    "...Snow-blindness is another example of uv inflamation; the snow reflects uv while most other substances absorb it strongly...."

    Huh. Now I know.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Help! Why can't we see ultra-violet light?
  1. How do we see violet? (Replies: 2)

Loading...