Optical systems are ubiquitous in modern society, with an ever-increasing number of applications covering medical sciences (vision technologies, surgical instrumentation, medical imaging, drug delivery or cancer photothermal therapies), spatial exploration (telescopes, lenses, spectrometers), telecommunications (fiber optics), information processing (quantum computing), industry (from cutting, welding to precision metrology), military/weaponry technology or optoelectronics, to name but a few examples. Furthermore, laser and optical technology are in general essential to perform applied research in areas such as chemistry and biology, providing fundamental analysis tools. The success of optical systems and technologies in high-end scientific research has also found its way into everyday consumer products such as printers, displays, discs, cameras, and eyeglasses, not to forget that optical fiber is crucial to telecommunications in general and internet in particular.