Vision guides the growth of the eye: if spectacle lenses cause images to fall either behind or in front of the retina (hyperopia or myopia, respectively), eye growth compensates for the optical effects of the lenses

https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom...

The eyeball is not “just” too long. It elongates as a response to the stimuli from the lens projecting an image at a focal length behind the retina. Most kids are not born nearsighted. It develops over time. This is how.

So, they eye works pretty much like a camera - but it's not a camera: it's a complex dynamic self-assembling, self-tuning adaptive structure.

The fact that it's geometry is roughly static around a focal length that has sharp focus on the retina is a wonder of homeostasis with at least three known tuning loops:

1) the lens Moving on swiftly...

2) a slower feedback loop adjusting the choriod (hence focal length) in the order of hours.

3) an even slower loop adjusting the eye geometry over longer periods of time.

check out: https://www.sciencedirect.com/science/article/pii/S089662730...