Christiaan Huygens

Biography

Born in The Hague. He studied at Leiden University and Breda University. He worked at the Paris Academy of Sciences, where he enjoyed the patronage of Louis XIV. He returned to Holland at the end of his life. He maintained extensive correspondence with contemporaries, including Newton and Leibniz.

Key discoveries

• Wave theory of light — proposed that light propagates as waves, and successfully explained reflection, refraction, and double refraction in Iceland spar.
• Invention of the pendulum clock — first applied a pendulum to regulate the movement of a clock, significantly increasing its accuracy, and received a patent.
• Discovery of Saturn's rings and Titan — using a telescope he made himself, he correctly described the rings as a system of solid particles and discovered Saturn's largest moon.
• Theory of centrifugal force — derived the formula for centrifugal acceleration and investigated the motion of a pendulum along a cycloid.
• Huygens' principle — each element of a wavefront is a source of secondary waves, which underlies modern wave optics.