Glossary

Laser: acronym of : « light amplification by stimulated emission of radiation » ; device emitting spatially and temporally coherent light radiation based on the stimulated emission
Waist: position along the propagation axis where a laser beam has the smallest size
Gaussian beam: beam with a gaussian distribution of intensity in the plane perpendicular to the direction of propagation - fundamental transverse mode of a laser
Lens: optical component with two refractive surfaces axially symmetrical for redirecting the light in a controlled manner
Afocal system: optical system without focal planes, so that the image of a point at infinity is also at infinity
Effective focal length: algebraic distance from the primary/secondary principal plane of an optical system to its front/back focal plane