Optics is the branch of physics that deals with visible light and other electromagnetic waves. Light has a “dual personality” since it sometimes behaves like a wave and other times like corpuscles or discrete packets of energy called photons. This is known as its “wave-corpuscle duality”. Just as the term electronics was derived from electron, in recent years the term Photonics has been coined from photon. Although the terms optics and photonics are often used indiscriminately, the latter is sometimes used to underline the corpuscular nature of light. The number of devices and systems that operate with light is constantly increasing and the many different fields in which these are used are referred to as “light-based technologies”.

Reflection holograms of the Treasure of Villena made by J. A. Quintana at the University of Alicante (http://en.wikipedia.org/wiki/Treasure_of_Villena) Credit: A. Beléndez


