There is documented evidence that for the first few days, babies do see everything UPSIDE DOWN. This is because their visual cortices have not yet recognised that the image reaching the retina is inverted. Whether babies can see anything at all is another debate. The approximate visual acuity from birth is between 6/120 to 6/240.
It’s not been established when babies invert things to see the ‘right way round’ but it’s likely to take only a few days/weeks to adjust.
Between 4-8 weeks, babies can mainly focus on objects 8 to 10 inches from their face or the distance to parent’s face or other person near them.
Babies begin to follow moving objects with their eyes and reach for things at around 3 months of age and their Visual acuity is approximately 6/60.
From 4 months depth perception and eye-hand coordination begin to develop.
By 5 months colour vision starts to develop and from
6 months the visual acuity is approximately 6/30.
It will take children on average between 4-6 years old to achieve 20/20 or 6/6.