What are Real and Virtual Images?

Looking at a mirror

When you look at a mirror, you see your own image on it.

A plane mirror reflects any light falling on it, which enables us to see the image.

Let us see the image formation with an example

Suppose an object is placed in front of a concave mirror at some distance.

If a screen is placed near the object, an inverted image is observed on the screen.

Let’s understand this in detail with the help of a ray diagram

A mirror in which the reflecting surface is curved inwards is known as a concave mirror.

When a parallel beam of rays is incident on a concave mirror, it reflects and converges at a point.

This point is known as the focal point and its distance from the mirror is the focal length.

Focal length(f) is half of the centre of curvature(c).

Now we’ll see the images obtained for different cases

If the object is placed beyond the focal point, a real and inverted image is obtained.

If the object is placed at the focal point, a virtual image is obtained.

If the object is placed within the focal point, an erect, virtual and magnified image is obtained.

So, a real image is formed when the light rays coming from an object actually meet each other after reflection.

A virtual image is formed when the light rays coming from an object do not actually meet,

but appear to meet when produced backward.

A real image can be obtained on a screen while a virtual image cannot be obtained on a screen.

Let us now study the image formed by a plane mirror

Consider an object that is placed before a plane mirror.

Then, a virtual is formed in the mirror.

And since it is a virtual image, no image can be obtained on a screen.

Revision

A real image is formed when the light rays coming from an object actually meet each other after reflection.

A virtual image is formed when the light rays coming from an object do not actually meet but appear to meet when produced backward.

A real image can be obtained on a screen while a virtual image cannot be obtained on a screen.

The End