You may know them best for their original use in lighthouses, where they're famously recognised as "the invention that saved a million ships". Or perhaps you initially think of their employment in ...

Fresnel lenses consist of a flat surface with interspaced, concentric steps whereby each step corresponds to the surface of a conventional lens. Each step thereby acts as a refractive surface, much ...

More than 2,000 lighthouses large and small watch over Norway’s fractal, rocky coast. Some have stood for centuries, guiding mariners through treacherous seas and safely to port. Now they all must be ...