Optical phenomena result from the behaviour and properties of light, including its interactions with matter. They include absorption, dispersion, diffraction, polarization, reflection, refraction, scattering and transmission.
- Optics is the branch of physics which 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.
- 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.
- Practical applications of ray diagrams are found in relation to a variety of technologies and descriptions of how everyday objects work, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics.
