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If you wear glasses please look at this picture! optical illusion?

  1. Nov 15, 2011 #1
    While drawing a computer chassis i'm designing, i came across a really weird optical illusion. it only seems to work with my glasses on. i put sun glasses on and could see it move a little, but with classes if you stare at the hexagons and move your head while looking at them, everything shifts, not just a little like a full inch back and fourth.

    if you zoom in a lot it still does it. i think it's the coloration of the pixels and how my glasses (polycarbonate lens no anti glare coating) reflect the different colors, making it appear to shift. I can't figure it out completely and its making me trip balls.

    i'm in a fluorescent lit room if it makes a difference.

    does anyone else with glasses see this?

  2. jcsd
  3. Nov 15, 2011 #2
    on second thought it could have something to do with the way my monitor is set up. samsung LED monitor, maybe it has oblong shaped pixels that look different from a different angle. freaking me out either way.
  4. Nov 15, 2011 #3


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    Yeah, its not doing anything to me. It's probably your monitor.
  5. Nov 15, 2011 #4


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    yeah, the blue ones (hexagon and the rectangle) moves with my head while others stay still. doesn't work without glasses, my monitor is a cleap TN viewsonic
  6. Nov 15, 2011 #5


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    I wear glasses, see nothing happening.
  7. Nov 15, 2011 #6


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    What he/she said, except for the part about the monitor (because I don't have that kind of monitor).
  8. Nov 15, 2011 #7
    No, nothing.
  9. Nov 15, 2011 #8

    Ben Niehoff

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    It is not your monitor, it's your glasses.

    In most glass, the index of refraction is not the same for all wavelengths of light. White light tends to break up into many different wavelengths, just like shining a white beam of light through a prism. This phenomenon is known as "chromatic aberration," and causes no end of headaches for designers of camera lenses.

    You can observe chromatic aberration from your glasses in more ordinary circumstances if you pay attention. Hold up a piece of white paper (under reasonably-white light) and look at the edge of the paper while turning your head side-to-side. You should see the left edge appearing blue while the right edge appears yellow, or vice versa, depending on which way you've turned your head. The more you turn your head, the more pronounced should be the effect.

    The reason this happens is that the image of the white paper is being split into several images of different colors. Bluer images shift one direction, while more red/yellow images shift the other direction. Most of these images overlap, so you see mostly a white sheet of paper. But near the edges, some of the images do not fully overlap, allowing you to see the individual color.

    In your computer drawing, the blue hexagons are a pure shade of blue, so there is no yellow image to shift in contrary motion to the blue. Hence all you see is that the blue moves back and forth. If you look closely at the grey band on the left, you should also see a fringe of either blue or yellow appear as you turn your head.
  10. Nov 15, 2011 #9


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    I see nothing happening with and without my glasses, with and without zooming, with and without looking through the part of my lenses with the most chromatic aberration.
    My monitor is also a LCD, LG.
  11. Nov 15, 2011 #10
    ok for those of you without glasses, i don't want this to be unequal because of you're from a "superior visioned species" so you will have to take a hit of LSD, wait 42 seconds, and retry.
  12. Nov 15, 2011 #11
    thanks, i thought it was something to this effect. but, what i don't get though (not sure if you can see the effect or not) is how far the blue box actually moves, i can see turning a different shade, but it looks like it shifts about an inch, i will hold my finger next to it and it will shift into my finger. really weird.
  13. Nov 16, 2011 #12
    i see the blue ones move as i turn my head left or right. it's a pretty big shift, too, but i've also got the thin, high-index-of-refraction lenses, too. neat trick.

    speaking of this, i guess it might also explain why i loathe the combination of Blue/Red or Blue text on Black background on web pages. it feels like it makes my eyes vibrate.
  14. Nov 17, 2011 #13


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    Woooaaaahhhhh!!! :bugeye:
  15. Nov 17, 2011 #14
    Same. With or without glasses. And I almost always see whatever optical illusions are supposed to make you see.
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