By Peter Weiss
Two thousand years ago, Roman Emperor Nero peered through an emerald monocle to better see his gladiators in combat. Twelve hundred or so years later, eyeglasses started to adorn faces. Up to the present, lenses have primarily served one purpose: to render the world more visible–to people, that is. Now, there are inanimate observers that can also benefit from lenses. More and more, computers are being tasked with making sense of the visual world in ways that people can’t.