Photonics Dictionary: I

In semiconductor physics and materials science, the term "III-V materials" refers to compounds composed of elements from group III and group V of the periodic table. More specifically, these...

A method used in imaging to detect subtle differences between two apparently similar pictures. It can be achieved by superimposing the negative of one photograph over a contact print of another, by...

A machine vision technique that compares a template of the desired image (the correlation kernel) with the actual camera image of an object and generates a new image (the correlation image) that...

An image intensifier, also known as an image intensification tube or image intensification device, is a specialized electronic device used to amplify low-light-level images to make them visible to...

The technique that uses light to detect and analyze the antibodies produced by a specimen stained with an organic dye.

In the context of optical materials, the term "impurity level" refers to the presence of foreign atoms or molecules within the material that deviate from its regular or intrinsic composition. These...

In vitro is a Latin term that translates to "in glass." In scientific contexts, particularly in biology and medicine, it refers to experiments or procedures conducted outside of a living organism,...

In vivo is a Latin term that translates to "within the living." In scientific contexts, particularly in biology and medicine, it refers to experiments or observations conducted within a living...

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)....

An InGaAs (indium gallium arsenide) camera is a type of imaging device that utilizes InGaAs sensors to capture images in the near-infrared (NIR) spectrum. InGaAs is a semiconductor material that is...

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...

Induced pluripotent stem (iPS) cells are ordinary cells that are genetically reprogrammed to an embryonic stem cell-like state to allow the human cells to be used for therapeutic purposes....

A thermal infrared imaging procedure developed for quality control of printed circuit boards. The thermogram of each board under test is compared with a standard thermal profile and then with a...

An infrared source, set in a stationary position, that is used as a reference in certain navigational systems.

An infrared detector is a device that is used to detect and measure infrared radiation, which lies beyond the visible spectrum of light. These detectors are utilized in various applications,...

A countermeasure used against heat seeking missiles to reduce their effectiveness. Normally it involves the emittance of infrared radiation at a level that will overload the missiles' detectors.

An infrared lens is an optical component specifically designed and optimized for transmitting, focusing, or manipulating infrared (IR) radiation within the infrared spectrum. These lenses are used in...

An infrared light source is a device that emits light in the infrared spectrum, which lies beyond the visible spectrum of light. Infrared light has longer wavelengths than visible light and is...

An infrared light-emitting diode (IR LED) is a semiconductor device that emits infrared light when an electric current passes through it. Similar to standard LEDs that emit visible light, IR LEDs are...

The range of materials that, unlike glass, may be used in the infrared. Water-soluble salts, such as cesium iodide, and other substances such as arsenic sulfide, selenium, thallium bromide-iodide and...

An InGaAs photodiode refers to a photodetector device that is constructed using a semiconductor material composed of a combination of indium (In), gallium (Ga), and arsenic (As). The term InGaAs...

A method of producing high-quality plastic optics in large volumes by injecting the heated, liquified plastic at high pressure into a tooled mold with polished chromium stainless steel inserts to...

Instantaneous field of view (iFOV) is a term commonly used in the context of remote sensing, imaging systems, and optical instruments. It refers to the specific portion of a scene that an optical...

Integration time, in the context of optics, imaging systems, and sensor technology, refers to the duration over which a sensor collects and accumulates incoming light or signal. It is a crucial...

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...

Sharp and narrow absorption lines found in the spectra of stars. They result from the absorption of a part of a star's emittance by interstellar gases.

An absorbing coating medium between fibers, used in some fused fiber optic plates to absorb unwanted light. Such coatings are sometimes called EMA (extramural absorption).

That distortion resulting from dispersion of the group velocity of a propagating mode. It is the only distortion occurring in single-mode waveguides.

Intravital microscopy is an imaging technique used to visualize biological processes within living organisms, typically in real-time. Unlike traditional microscopy, which involves the examination of...

The absorption of a photon raising an electron across the forbidden gap from valence to conduction band of the semiconductor where conductivity is increased and incident radiation may be measured.

An atom that has gained or lost one or more electrons and, as a result, carries a negative or positive charge.

A laser in which the transition involved in stimulated emission of radiation takes place between two levels of an ionized gas. The gases are electrically excited in a container called a plasma tube,...

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,...

Also known as gas focusing. The introduction of an inert gas into a cathode-ray tube for the concentration of the electron beam. The gas molecules are ionized by the electrons, producing a core of...

A closed vessel with electrodes of different potentials that is used to determine how much ionization took place in a gas after its exposure to x-rays or radioactive emissions.

A type of radiation detector that depends on the ionization produced in a gas by the passage of a charged particle through it. One of the best known is the Geiger-Müller counter, although cloud...

The gas of charged particles that begins approximately 50 km above the surface of the Earth and contains a sufficient quantity of electrons and ions to affect the propagation of radio waves.

The points on a photographic negative that are of equal density.

In the context of electronics and optics, an isolator refers to a device that allows the transmission of signals in one direction while attenuating or blocking signals in the opposite direction. The...

A direct recording photometer that is designed to scan a photographic negative to determine its points of isodensity.

That property of a material that determines that velocity of propagation within the material is the same for all directions.