LASERS

A comprehensive set of flashcards covering key terms, concepts, and definitions related to lasers and their applications in medicine.

Spontaneous Emission

The process in which an atom in an excited state emits a photon without external influence, resulting in incoherent light.

Stimulated Emission

Emission of radiation from an excited atom that is induced or stimulated by an incoming photon of the same energy.

Population Inversion

A condition in which the number of atoms in an excited state exceeds the number in a lower energy state, enabling laser action.

Optical Resonator

A structure formed by mirrors that allows light to travel back and forth through the gain medium, amplifying the light.

Gain Coefficient

A measure indicating the increase in light intensity per unit distance in the laser medium, typically requiring population inversion.

Bouguer-Lambert Law

A principle that relates the absorption of light to the properties of the material through which it is traveling.

Einstein Coefficients

Coefficients that represent the probabilities of spontaneous and stimulated emission and absorption processes.

Thermal Radiation

Incoherent radiation emitted by bodies at finite temperatures as a result of thermal processes.

Coherence

The property of light waves that allows them to maintain a constant phase relationship, essential for laser operation.

Excimer Laser

A type of laser that uses excimer gases (like noble gases combined with halides) to produce ultraviolet light.

Maser

A device that produces coherent microwave radiation similar to how a laser produces optical radiation.

Wavelength (λ)

The distance between successive crests of a wave, typically associated with the type of laser and its applications.

Refractive Index

A measure of how much light slows down as it passes through a medium compared to its speed in vacuum.

Photodynamic Therapy (PDT)

A treatment that uses light-sensitive drugs and light exposure to destroy cancer cells.

Photochemical Reaction

A chemical reaction initiated by the absorption of light, often relevant in biological processes.

Selective Photothermolysis (SPTL)

A method where laser light is selectively absorbed by tissues containing specific chromophores, minimizing damage to surrounding areas.

Laser Scalpel

A surgical tool that uses the focused light of a laser to cut or destroy tissue with high precision.