Photonics Dictionary

Dewetting is a phenomenon in materials science and physics where a thin film or coating spontaneously undergoes a process of breaking up and forming isolated droplets on a substrate. This occurs due...

Diamond turning, also known as diamond machining or diamond cutting, is a precision machining process used to produce high-quality optical surfaces and components with extremely tight tolerances. It...

Diamond turning refers to a precision machining process used to produce complex optical components, particularly lenses and mirrors, from materials such as metals, plastics, and crystalline materials...

Dichalcogenides are a class of compounds composed of two atoms of a chalcogen element bonded to a single atom of a metal or metalloid element. Chalcogens are the elements in group 16 of the periodic...

A diffraction grating is an optical component consisting of a surface with a periodic structure of equally spaced, parallel grooves or rulings. These rulings act as an array of closely spaced slits...

A microscope objective designed to be used without liquid between the cover glass and the objective, or, in the case of metallurgical objectives, between the objective and the specimen.

An electrochemical process of metal fabrication using an electrolyte, an anode to supply the metal, and a control of the electrical current and of the deposit of metal on the matrix of a reflector.

The deposition of a metallic coating, usually nickel, on a component by chemical means rather than by electroplating; the component is immersed in a solution containing a reducing agent.

The bending of an electron stream that occurs when the stream travels through a medium such as very thin metal foil.

That branch of metallurgy that uses electron microscopic techniques in the examination of the nature of metals.

The recording of the information contained in a modulated electron beam onto photographic or silicon resin-coated materials. A direct recording method involves the passage of the recording medium...

A small xenon-filled tube with metal electrodes fused into the ends. The gas flashes brilliantly when a condenser is discharged through the tube. The duration of the flash is primarily dependent upon...

That branch of science involved in the study and utilization of the motion, emissions and behaviors of currents of electrical energy flowing through gases, vacuums, semiconductors and conductors, not...

Emission spectroscopy is a technique used to study the emission of electromagnetic radiation (light) by atoms, molecules, or ions when they undergo transitions from excited states to lower energy...

An endoscope is a medical device used for visualizing and examining the interior of hollow organs, body cavities, or confined spaces within the body. It consists of a flexible or rigid tube equipped...

Also referred to as a bulb. The glass housing that encloses an incandescent source, or the glass or metal housing that encloses an electron tube.

Epitaxial deposition is a process used in semiconductor manufacturing and materials science to grow a thin crystalline layer, known as an epitaxial layer, on a substrate. The term epitaxial refers to...

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 acid used to etch the surfaces of particular materials. For glass, hydrofluoric acid is used either as a liquid or a vapor. Metals are etched by means of suitable acids or other liquids, often to...

The light spectrum formed by an explosive reaction or by the electrical explosion of a metallic wire by a strong current.

A shield of rubber, plastic or metal used to protect the eyes of the observer from stray light and wind, and to maintain the proper eye distance.

A laser with output over a wide range of wavelengths spanning the far-infrared region of the spectrum (30 to 1000 µm); typically, it consists of a metal or dielectric waveguide one to two...

The Fermi liquid state refers to a specific state of matter in quantum mechanics, particularly describing the behavior of interacting fermions (particles with half-integer spin, such as electrons) at...

A fiber laser is a type of laser in which the active gain medium is an optical fiber doped with rare-earth ions such as erbium, ytterbium, or neodymium. Fiber lasers generate coherent light through...

A fiber optic spectrometer is a device used for measuring the spectral content of light. It utilizes optical fibers to transmit light from a source to a spectrometer unit, where the light is...

A device that is designed to automatically turn electric lamps on and off in a rapidly repeating sequence. The device may use a motor-driven mechanism or a combination heater filament and bimetallic...

Fluorescence and phosphorescence spectroscopy are techniques used to study the emission of light (photons) by molecules following their excitation by external energy sources. While both processes...

A highly stable heavy-metal fluoride glass made from the fluorides of zirconium, barium, lanthanum, aluminum and sodium.

A solid-state laser consisting of active atoms or ions of a transition metal, rare-earth metal or actinide, imbedded in a crystal or glass material, often garnet. Excitation and transfer to different...

Gallium arsenide phosphide (GaAsP) is a semiconductor alloy composed of gallium (Ga), arsenic (As), and phosphorus (P). It is commonly used in the fabrication of optoelectronic devices, particularly...

The emission of radiant energy produced by the passage of an electrical current through an appropriate electrolyte in which an electrode, made of certain metals such as aluminum or tantalum, has been...

Also called Geiger-Müller counter. An instrument designed to detect and measure radioactivity through the use of a gas-filled metallic tube containing a needle electrode. Radiation traveling...

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 noncrystalline, inorganic mixture of various metallic oxides fused by heating with glassifiers such as silica, or boric or phosphoric oxides. Common window or bottle glass is a mixture of soda,...

Gold colloid aggregates refer to clusters or assemblies of gold nanoparticles suspended in a liquid medium. These aggregates are formed when individual gold nanoparticles come together due to various...

Describing a surface that is coated with a film of metal of such thickness that it transmits about one-half of the incident light and reflects about one-half.

A test for spherical aberration, coma or astigmatism in which incident rays from a point source are isolated by small holes in a metal disc located close to the lens or mirror under test....

The heat-affected zone (HAZ) refers to the portion of a material, typically metal, that experiences changes in its microstructure and mechanical properties due to the heat generated during welding,...

A heat sink for a laser is a device designed to absorb and dissipate the excess heat generated by the laser during operation. This is crucial to maintain the laser's performance, prevent overheating,...

The process of subjecting glass to temperature cycling to produce physico-chemical reactions that alter its properties. Similar processes can be accomplished with a laser -- most commonly a CO2,...

A high-speed motion camera, also known as a high-speed camera or slow-motion camera, is a specialized imaging device designed to capture fast-moving events or phenomena at extremely high frame rates....

A lamp that emits light when an electric current passes through a resistant metallic wire situated in a vacuum tube.

Metal used in components of the crystalline semiconductor alloys indium gallium arsenide (InGaAs), indium gallium arsenide phosphide (InGaAsP), and the binary semiconductor indium phosphide (InP)....

Injection molding is a manufacturing process used to produce parts by injecting molten material into a mold. It is widely used for creating a variety of plastic products, but it can also be used with...