How is it possible for our vision to work?!


Question: How is it possible for our vision to work?
I have a few questions about vision and the eye that I'm trying to understand, since it seems that we shouldn't be able to see as well as we do:

1.) Why is peripheral vision blurry? Is it simply because there aren't any cones in this area of our visual field, or is it because light isn't actually focused there by the cornea and lens?

2.) Is there any functional reason that has been discovered as to why the fovea is not aligned with the optical axis of the eye, but rather at an angle to it? Shouldn't this mean that light isn't focused as much on the fovea as on the area next to it which is in line with the optical axis of the eye?

3.) Is there any reason why the retina doesn't extend over to cover the surface of the optic nerve?

4.) If the lens of the eye has different refractive indices in its different layers, doesn't this introduce aberrations since light isn't all focused the same amount?

Thank you so much, I really appreciate your answers!

Answers:

i think you already asked all these, didnt you?

1) BOTH of those. both no cones AND not the center of focus
2) this is what God decided to do. no, no real "functional" reason for it. maybe He decided it had something to do with stereopsis?
3) the axons (wires) of the retina have to exit the eye somewhere...
4) yes

optometrist
http://myeyepod.blogspot.com/



It is awesomely complex, #4 I believe partially explains #1. I believe #2 has to do with the greatest visual acuity causing a blind spot, as more work is concentrated in one spot and so other parts are cheated. If the two blind spots were in the same spot the eyes (plural) could not compensate to cover the spot. I read the explanation of 3. It was very technical about the creation and re absorption of chemicals involved in nervous transmission.




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