Photonics Dictionary: E

An Er:YAG laser is a type of solid-state laser that uses a crystal made of erbium-doped yttrium aluminum garnet (Er:Y3Al5O12) as the gain medium. The erbium (Er) ions are introduced into the crystal...

An optical fiber that can be used to amplify an optical input. Erbium rare earth ions are added to the fiber core material as a dopant in typical levels of a few hundred parts per million. The fiber...

An etalon is an optical device that consists of two parallel reflecting surfaces separated by a precise and known distance. It operates based on the principle of optical interference and is used to...

An excimer laser is a type of ultraviolet laser that emits short pulses of light in the ultraviolet spectrum. The term excimer is derived from excited dimer, reflecting the nature of the gain medium...

In laser pumping, parasitic absorption that occurs at certain wavelengths, decreasing pump efficiency and gain.

An exciton is a quasiparticle that represents the bound state of an electron and a hole in a solid-state material, typically a semiconductor or an insulator. In simpler terms, an exciton is a paired...

Extreme ultraviolet (EUV) refers to a specific range of electromagnetic radiation in the ultraviolet part of the spectrum. EUV radiation has wavelengths between 10 and 124 nanometers, which...

Wavelengths between 400 and 1400 nm (VIS to NIR) are focused onto the retina by the cornea. Because the retina is sensitive to light, these wavelengths can be damaging even at low energies. It is the...