The camera module

A stack of lenses smaller than a coin.

A phone camera is a stack of lenses smaller than a coin. Behind the lenses, a sensor turns light into numbers. Tiny motors move the whole stack to focus and to soak up the shaking of your hand. The rest of the work, the photograph itself, happens in the processor. The light path, which explains how an image becomes numbers, is waiting its turn. It will begin with a photon hitting silicon.