Virtual image cannnot be obtained on screen but seen through eyes, even if our retina is a screen ?

Question

Example- plain mirror show virtual image, but we can see our selves

Answer 1

A real image is only formed when light rays converge on an actual point in space...the light actually has to pass through that point to form the image.
A virtual image if formed when light *appears* to be diverging from a certain point (if its path were traced backward to where it appears to be coming from). When we see a virtual image, the light just looks as if it is coming from an actual point, but if one was to place a screen at that location, no image would be formed.

In the case of a plane mirror, the image we see appears to be coming from behind the mirror, but obviously any light which enters our eyes cannot be originating from that point...it cannot pass through the opaque backing of the mirrored glass. We see the light rays in the way they reflect off the mirror surface and we assume that if we follow their path backward that we will find the object they originated from...the virtual image in this case, but obviously we will not.

By contrast, in a real image, light actually does pass through the point. If we place a screen there, we will actually see an image form.
The lenses in our eyes act to form real images on our retinas to allow us to see.

Answer 2

Your retina is a screen... with a lens in front of it! Virtual images consist of diverging light rays. The lens in your eye converges the rays to form a real image on your retina.