Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Benham top?

  1. Jul 30, 2010 #1
    When i spin a benham top why do i see colors ,
    Is this because of the dashed black lines , that i am now pulsing white light , so now the white light is out of phase and the red , green , yellow photons are interfering so i see colors ,
    Is this is what is going on .
  2. jcsd
  3. Jul 30, 2010 #2
    Last edited by a moderator: May 4, 2017
  4. Jul 30, 2010 #3
    ok then whats going on , i know it as something to with pulsing white light so my brain will see colors .
  5. Aug 1, 2010 #4
    someone has to know something about a benham top .
    we are just spinning something with black and white on it .
  6. Aug 1, 2010 #5
    From a quick search, it seems that precise reasons are not known, but it may have to do with the reaction times of vision cells on our retinas.

    For example, cells that detect red may have a slighly different reaction time than cells that detect blue. In this case, the various white light pulses would be time-resolved by the nerve cells.

    But apparently, different people see different colors at diffrent areas and times, so I believe this is mostly a neurological issue, beyond what can be precisely described by physics.

    Perhaps someone could measure the reflection spectra with a spectrum analyser. I suspect no colors would be detected, other than the original white.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook