Optics

Optics is the branch of physics which involves the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.

Most optical phenomena can be accounted for using the classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray-based model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 19th century led to the discovery that light waves were in fact electromagnetic radiation.

Some phenomena depend on the fact that light has both wave-like and particle-like properties. Explanation of these effects requires quantum mechanics. When considering light's particle-like properties, the light is modelled as a collection of particles called "photons". Quantum optics deals with the application of quantum mechanics to optical systems.

Optical science is relevant to and studied in many related disciplines including astronomy, various engineering fields, photography, and medicine (particularly ophthalmology and optometry). Practical applications of optics are found in a variety of technologies and everyday objects, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics.

Read more about Optics:  History, Classical Optics, Modern Optics, Applications

Other articles related to "optics":

Applications - Atmospheric Optics
... Mirages are optical phenomena in which light rays are bent due to thermal variations in the refraction index of air, producing displaced or heavily distorted images of distant objects ... Other dramatic optical phenomena associated with this include the Novaya Zemlya effect where the sun appears to rise earlier than predicted with a distorted shape ...
Soliton (optics)
... In optics, the term soliton is used to refer to any optical field that does not change during propagation because of a delicate balance between nonlinear and linear effects in the ... solitons were discovered first and they are often simply referred as "solitons" in optics ...
Laser Physics (journal) - Topics Covered
... solids, Coherent phenomena and holography, Nonlinear and quantum optics, Ultrafast optics and strong-field physics, Fiber optics, Surface phenomena, Quantum information and computation, and ...
LAMOST - Optics
... The optics of LAMOST comprise two roughly rectangular mirrors, each made up of a number of 1.1-metre hexagonal deformable segments, providing a focal plane 1.75 metres in diameter corresponding ... Using active optics technique to control its reflecting corrector makes it a unique astronomical instrument in combining large aperture with wide field of view ...