[thedoc (OP)]

Ricardo Hernandez  asked the Naked Scientists:
   
Do human eyes have chromatic aberration?

How could we check this?

Thanks,

Ricardo

What do you think?

[Robert Dinse]

Because the amount of defraction is less at blue wavelengths than red, it follows that the human eye and any other lens system is going to have some chromatic aberration, it is just a question of how much.

The easiest way to tell is find a sharp black/white contrast somewhere and see if you see any red/blue fringes at the boundary.  If not, then there isn't enough chromatic aberration there for you to worry about.  Myself, there isn't enough in my eyes for it to be visible, but plastic lens glasses I can see it at the edge of the lens.  With glass lenses I don't.

[evan_au]

Isaac Newton thought that chromatic aberration was inherent in all lenses - so he invented the reflecting telescope which (in theory) doesn't need to use lenses.

Later workers discovered how to partially compensate for chromatic aberration by combining two lenses of different refractive index. To use this method, one of the lenses has to be a diverging lens, but I don't see anything this shape in the human eye.

When an optometrist prescribes glasses, they actually do a test to ensure that chromatic aberration is minimised - at least in the center of the lens.