Two shapes, two opposite jobs. Once you know which way each one curves, you can work out its use from first principles rather than memorising a list.
A funhouse mirror makes your reflection taller, shorter or wider. Look closely and you will see that its surface is not flat. Such mirrors are curved mirrors, and curved mirrors distort the images they form.
There are two types, and a spoon shows both at once: the top of a spoon is concave, and its bottom is convex.
A memory hook: a cave goes into a hillside, so concave curves inwards.
Also called a .
You do not need to memorise the application lists if you hold on to what each mirror does.
| Mirror | What it does to light | So it is used where you want… |
| Convex curves outwards diverging |
Spreads rays apart | …to see a wide area from one place: road junctions (around blind corners), shop corners, rear-view and side mirrors of cars. |
| Concave curves inwards converging |
Brings rays together | …to magnify something (dentist's mirror, shaving and make-up mirrors) or to concentrate light into a beam (car headlights, a microscope mirror lighting the specimen). |