Under the gun, Smith and Boyle went into an office and, in one hour, emerged with the basic plans for the CCD, the sensor still used in digital photography today. A CCD works like this: Light hits a tiny grid of photosensitive silicon cells, each which build a charge proportional to the intensity of the light hitting it. This charge can be measured precisely and we can know exactly how bright that portion should be. Add filters, and color can be discerned too.

Source: In just one hour, two Bell Labs scientists had a breakthrough that won the Nobel prize — and changed photography forever