Why are images laterally inverted

That is to say the image seen is inverted from left to right but not from top to bottom. When facing a mirror the left side of an object appears to be on the right side of the virtual image.

Similar to how a lens with rays going through the center go straight through without refracting, a concave mirror has the rays from an upright object bounce back at the center at the same angle and below principle axis so that the image formed by converging rays ends up inverted. The real images formed by the concave mirrors are inverted. The rays from the top edge of the object are reflected downwards below the principal axis by the concave mirror. Similarly, the rays from the lower edge of the mirror are reflected upwards.

This forms an inverted image. The only way we could look like that is if we turn round. Right and left are not actually reversed in the image; it is just our interpretation of the image. In fact what the mirror does is swap front for back. The back of our heads are furthest from the mirror and end up furthest behind it in the image.

Our faces start closest and end up closest. The mirror just turns us back to front. Here is something that sometimes convinces a class. First, find a large mirror which is safe to stand on without breaking and be sure you are wearing clothes which allow you to stand on the mirror trousers!

When the class see the image it is clear this time top and bottom have been swapped, not left and right. As before, in fact, the mirror has turned us back to front. And here is the final test to show that it is not really about left and right. Get a pupil to lie in front of a biggish mirror. The pupil will tell you that left and right have been swapped.

Virtual objects are points towards which light converges. If there were no eye or optical instrument in the way, there would be real images at these points. When an object is placed between pole and focus, the image created by the concave mirror is magnified, virtual and erect. When an object is placed beyond the centre of curvature, an image of it happens between centre of curvature and focus which is a real image of real object.

Concave mirrors can produce both real and virtual images; they can be upright if virtual or inverted if real ; they can be behind the mirror if virtual or in front of the mirror if real ; they can also be enlarged, reduced, or the same size as object. Plane mirrors and convex mirrors only produce virtual images.