Photonics Dictionary

A fluorescent screen refers to a phosphorescent or fluorescent-coated surface that emits visible light when exposed to other forms of electromagnetic radiation, such as x-rays or ultraviolet light....

A fluorophore is a molecule or a portion of a molecule that has the ability to emit light upon excitation by an external energy source, such as ultraviolet or visible light. The process by which a...

The phenomenon whereby an electron within a band absorbs radiation by transferring from a low-energy level to an empty high-energy level.

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a beam of accelerated electrons as the lasing medium. Unlike traditional...

Fusion ignition refers to the point in a controlled nuclear fusion reaction where the energy released by the fusion reactions becomes self-sustaining, leading to a continuous release of energy...

A GaAlAs laser is a type of semiconductor laser diode that emits light in the near-infrared region of the electromagnetic spectrum. It is composed of layers of gallium, aluminum, and arsenic, hence...

Gain-switching is a technique used in lasers to generate short pulses of light by modulating the gain of the laser medium. This method is distinct from Q-switching and mode-locking, two other common...

Gallium nitride (GaN) is a compound made up of gallium (Ga) and nitrogen (N). It is a wide-bandgap semiconductor material that exhibits unique electrical and optical properties. Gallium nitride is...

Gallium nitride-based light-emitting diodes (GaN-based LEDs) are semiconductor devices that emit light when an electric current passes through them. These LEDs are constructed using gallium nitride...

One of the first lasers to find practical application. Generally, the pumping mechanism is an electric discharge, although some high-power forms employ chemical reaction or gas compression and...

Germanium crystal refers to a crystalline form of the element germanium (Ge), which is a metalloid and semiconductor commonly used in various electronic and optical applications. Germanium crystals...

A halogen lamp, also known as a tungsten halogen, quartz-halogen, or quartz iodine lamp, is an incandescent lamp that uses a tungsten filament surrounded by a small amount of halogen gas, such as...

Harmonic generation refers to a nonlinear optical process in which incoming photons interact with a material and produce new photons at integer multiples of the frequency of the incoming photons....

A helium-neon (HeNe) laser is a type of gas laser that emits visible red light at a wavelength of 632.8 nm. It operates based on the principle of stimulated emission of photons from excited helium...

High harmonic generation (HHG) refers to a nonlinear optical process in which intense laser light interacts with a gaseous medium, typically an atom or a molecule, to produce harmonics of the...

A cloud chamber designed to maintain the gas within it at a high pressure as a means of reducing the range of the high-energy particles and, subsequently, increasing the chances of observing...

Holmium lasers are a type of medical laser that utilizes holmium-doped crystals as the gain medium. The term holmium laser is often associated with a specific type of laser used in urology for...

Indium phosphide (InP) is a compound semiconductor material composed of indium (In) and phosphorus (P). It belongs to the III-V group of semiconductors, where elements from groups III and V of the...

Inertial confinement fusion (ICF) is a method of achieving nuclear fusion, a process where two atomic nuclei combine to release energy. In the case of inertial confinement fusion, the fusion reaction...

Inertial fusion energy (IFE) refers to a proposed method of generating electricity by harnessing the energy released from the fusion of light atomic nuclei, typically isotopes of hydrogen, through a...

An infrared camera, also known as a thermal imaging camera or IR camera, is a device that captures and visualizes the infrared radiation emitted by objects, revealing temperature variations across...

An interband cascade laser (ICL) is a type of semiconductor laser that operates based on interband transitions between energy bands in a semiconductor material. Unlike traditional semiconductor...

A filter that controls the spectral composition of transmitted energy partially by the effects of interference. Frequently, these filters are made up of thin layers of metals and dielectrics,...

Interferometric modulator display (IMOD) is a type of display technology used in electronic devices, known for its energy efficiency and ability to produce high-quality reflective color displays....

Ion-beam sputtering (IBS) is a physical vapor deposition (PVD) technique used for depositing thin films onto substrates. It involves bombarding a target material with a beam of energetic ions,...

Laser ablation is a process that involves the removal or erosion of material from a target surface using laser energy. This technique is widely used in various scientific, industrial, and medical...

A laser cavity, also known as an optical cavity or resonator, is a fundamental component of a laser system. It is a confined region or space where light undergoes multiple reflections, leading to the...

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of lasers. The primary function of the laser crystal is to amplify light by...

Laser lithotripsy is a medical procedure that uses laser energy to break down or fragment stones in various parts of the body, particularly in the urinary and biliary systems. The term "lithotripsy"...

The laser output refers to the generated and emitted light produced by a laser system. This output is characterized by several key properties that distinguish lasers from other light sources. These...

Laser peening is a surface enhancement technique used to improve the mechanical properties of materials, particularly metals. It involves the use of high-energy laser pulses to generate shockwaves on...

Laser powder bed fusion (LPBF) is a type of additive manufacturing (AM) or 3D printing technology that uses a high-power laser to selectively fuse or melt layers of powdered material to build up a...

A nondestructive test, also referred to as LASAT, that uses a high-energy laser pulse that is targeted on an adhesively bonded part, resulting in the formation of plasma on its surface and,...

Laser shock peening (LSP) is a surface treatment process used to enhance the mechanical properties and durability of materials, particularly metals. It involves the use of high-energy laser pulses to...

Laser texturing is a manufacturing process that involves using a laser beam to selectively modify the surface of a material, creating textures, patterns, or microstructures. This technique is...

A laser, which stands for "light amplification by stimulated emission of radiation," is a device that produces coherent and focused beams of light through the process of optical amplification based...

Laser-induced fluorescence (LIF) is a spectroscopic technique that involves using a laser to excite molecules or atoms, leading to their emission of fluorescence light. This technique is widely used...

Laser-mediated gene transfer refers to a technique in molecular biology and genetic engineering that utilizes lasers to introduce genetic material into cells. This method is a type of gene delivery...

An LED, or light emitting diode, is a semiconductor device that emits light when an electric current passes through it. LEDs are widely used in various applications due to their energy efficiency,...

Fiber that emits luminescent radiation excited by ultraviolet, x-ray or high-energy particles.