Photonics Dictionary: I

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...

Also called calcite. A natural hexagonal crystal of calcium carbonate. It cleaves readily into rhomboids useful in the study of polarized light.

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...

In optics, an image is the reconstruction of light rays from a source or object when light from that source or object is passed through a system of optics and onto an image forming plane. Light rays...

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...

A camera tube widely used in television broadcasting. It consists of three sections within a single vacuum envelope. 1. A photosensitive film sometimes called the photocathode. The scene to be...

Immunohistochemistry (IHC) is a method for detecting antigens or haptens in cells of a tissue section by using labeled antibodies to bind specifically to their antigens. IHC is used for disease...

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...

The decrease in the refractive index at the center of a fiber's core, caused by certain fabrication techniques. Also called profile dip.

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...

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...

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 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 impurity-doped silicon detector array sensitive to long infrared wavelengths, installed in optical collecting systems capable of detecting the presence of infrared-emitting objects at extensive...

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...

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 intensified charge-coupled device (ICCD) camera is an advanced imaging device that combines the capabilities of both an image intensifier and a charge-coupled device (CCD) sensor to achieve...

A CCD image sensor that uses a proximity-focused image intensifier to provide greater sensitivity at low light levels.

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....

In a heterodyne optical receiver, the frequency that is the difference between that of an incoming laser signal and that of the local oscillator laser. Also called beat frequency.

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).

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...

A photodetector composed of a photoconductive material that, when exposed to radiation, conducts without the aid of added impurities and does not have to be cooled to the level of extrinsic material....

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 the Bragg spectrometer. A system used for the x-ray analysis of crystal structure. In the instrument, a homogeneous beam of x-rays is directed on the known face of a crystal and the...

Radiant flux incident per unit area of a surface. Also called radiant flux density.