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Absorbing and reflecting light

  1. Jul 18, 2011 #1
    Is there anything that absorbs light from one side and reflects it on the other?
  2. jcsd
  3. Jul 19, 2011 #2
    Virtually every common surface both absorbs and reflects light. Did you mean something that absorbs ALL light on one side and reflects ALL light on the other? If so, I do not believe that any such contraption exists. Prove me wrong, someone!
  4. Jul 19, 2011 #3
    whatelse do you think transperent substances do ??
  5. Jul 19, 2011 #4
    I read that you can trap light in a box using one way mirrors, but I read the way one way mirrors work is that one side must be dark (the clear and transparent side) and the lighting on the other side must be normal (the mirror side)
  6. Jul 19, 2011 #5
    The event horizon of a black hole?
  7. Jul 19, 2011 #6
    A mirror painted black on its back will strongly reflect light incident on its front surface and strongly absorb light incident on its back surface. Do you have something http://www.scientificsonline.com/solar-radiometer.html" [Broken] in mind?
    Last edited by a moderator: May 5, 2017
  8. Jul 19, 2011 #7
    This is interesting but it is not what I had in mind. I am trying to make a wave guid, by absorbing light from outside and then having the light bounce around inside my project.
  9. Jul 19, 2011 #8
    "Absorbing" may not be the proper term for what you want. It seems that you want the wall to be transparent for light coming from outside and reflective for light coming from inside the guide.
    If the light is absorbed by the wall you'll have no light going inside the guide. It will just heat up the wall.
  10. Jul 19, 2011 #9
    Yes this is what I want, does this exsist ?
  11. Jul 19, 2011 #10
    Or even how can I make it
  12. Jul 19, 2011 #11
  13. Jul 19, 2011 #12


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    No, the event horizon is merely a boundary around a black hole where the gravitiational pull becomes strong enough to trap light. It is not a physical object. It also doesn't absorb or reflect light.
  14. Jul 21, 2011 #13


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    There's nothing that is reflective on one side and transmissive on the other side. Such a material would violate the second law of thermodynamics. But there may be other ways to achieve what you are trying to do, maybe by concentrating light with mirrors. Are you building a solar oven or something?
  15. Jul 25, 2011 #14
    Kinda in a way. But how can this be achieved while maintaining a cost efficient standard? Any recommendation or suggestion is helpful.
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