University of Edinburgh

BSL Physics Glossary - image - definition

An image is what you see, like this hammer. But how is the image made? In fact the image that appears on the back of your eye is very small, and upside down! If you have a tree, then a lens and a screen, light will come from the tree, through the lens to make an image of the tree upside down on the screen. The tree looks small and upside down (inverted). An image is also formed by a mirror. What you see in the mirror is not real, it is an image. You are real; the image looks as if it is behind the mirror. It looks exactly like you.