Are all objects projected as an inversion on to the retina?

Question

how does this work?

Answer 1

Yes, the lens is a convex (converging lens) which produces a real, inverted image.The brain knows this and so we perceive the image as being the right way up.

This also happens in an astronomical telescope, the image is upside-down but this doesn't matter when viewing a star. In a terrestrial telescope there is an inverting lens added to make the image appear the right way up to us.

Answer 2

yes. the brain has amazing ability.  Years ago some people were fitted with prism glasses that inverted the objects...the brain perceived them as being upside down but in a matter of days the objects were perceived as being right side up.