Photonics Dictionary: V

A multilayer antireflective thin-film coating, so called because its reflectance rises steeply at wavelengths above and below a narrow band at zero. The v-coat is particularly useful in high-power...

Lasers based on neodymium-doped yttrium or gadolinium vanadate crystals. These include yttrium vanadate (Nd:YVO4), gadolinium vanadate (Nd:GdVO4), and lutetium vanadate (Nd:LuVO4). Vanadate lasers...

See laser Doppler velocimeter; laser velocimeter.

A method of measuring negatively charged phase ions using a color-center or lead-salt diode laser.

A laser that has a surface-emitting semiconductor gain element coupled to an external mirror designed to complete the laser resonator. VECSELs can be electrically or optically pumped. The extended...

A vertical-cavity surface-emitting laser (VCSEL) is a type of semiconductor laser diode that emits light vertically from the surface of a semiconductor wafer. VCSELs are commonly used in various...

Vibrational spectroscopy is a type of spectroscopy that involves the study of the vibrational states of molecules. It is used to obtain information about the molecular structure, bonding, and...

A type of change in the energy levels of molecules in a laser that results in lasing action. Vibronic transitions are those between one electronic level and another.

A disc whose surface contains recorded digital data at high-packing densities arranged in concentric rings. The data, representing video frames, are both recorded and read by a laser beam.

An instrument that uses an erbium:glass laser to determine cloud height from the ground.

Volume Bragg gratings (VBGs) are specialized optical elements that consist of periodic variations in refractive index throughout the volume of a transparent material, typically a photosensitive glass...

Volumetric imaging refers to the capture, visualization, and analysis of three-dimensional (3D) information from a volume of space. Unlike traditional two-dimensional (2D) imaging, which provides...