Diploma Lecture 2014

It was only a few centuries ago that the best source of light came from burning oil scooped out of a whale's head. Innovation expert Steven Johnson discovers the unsung heroes of invention in the surprising journey from the candle to the neon lights of Las Vegas and the world of lasers.

Two-part series in which Professor Jim Al-Khalili shows how, by uncovering its secrets, scientists have used light to reveal almost everything we know about the universe.

In the mid-1660s, Isaac Newton bought a pair of prisms at a fair near Cambridge, which were to be the basis of a series of experiments that would unlock a secret that had occupied scientists for centuries - the nature of light itself.