Photonics Dictionary: I

Any object that emits radiation of a wavelength lying between about 0.75 to 1000 µm. A calibrated secondary source usually is a heated cavity (blackbody) or a filament lamp rated in wattage...

Generally, any radiation that can form ions, either directly or indirectly, while traveling through a substance.

Application of radiation to an object.

A theoretical instrument conceived of as a box that receives a beam of radiation of any arbitrary polarization angle and produces a new beam, coaxial with the incident beam, having a specified new...

Source of radiation defined or specified by its spectral power distribution.

An electron tube that employs electromagnetic radiation to produce a visual replica of an image produced on its cathode. Electrons ejected from the cathode by the incident radiation are accelerated...

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 radiation detector with its active medium mounted within a lens that focuses the radiation signal. The improvement in detector performance is a function of the indices of refraction of the lens...

The emission of light by thermal radiation of a temperature high enough to render the source of radiation visible.

A thermal source that emits less radiation than a blackbody under identical temperature conditions.

The light formed by visible radiation that, in traveling from light source to object, undergoes one or more reflections. In microscopy, it is the light that falls on the object at right angles to the...

Infrared radiation absorbed by crystals as a result of the excitation of lattice vibrations in which ions having opposite charges move relative to one another. These vibrations take place in a narrow...

A system that uses infrared detectors and related instrumentation to determine when abnormal amounts of infrared radiation, usually in the form of heat, are present in an area; used for the detection...

A superconducting bolometer, operating at very low temperatures, that is used to detect infrared radiation.

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 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,...

Any of the photoelectric and thermal detectors, spectrographs and monochromators, thermographs, scanners, amplifier tubes, snooperscopes and related equipment developed for use with infrared...

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...

A type of microscope that uses radiation in the infrared region to illuminate objects that are opaque to visible radiation. The microscope consists of two illumination systems (transmitted and...

Infrared optics refer to optical components and systems designed to manipulate and control infrared (IR) light, which lies beyond the visible spectrum. These components are crucial for various...

A phosphor, such as sulfide or selenide, that can be excited to luminescence by incident infrared radiation simultaneous to or following its excitation by visible radiant energy.

A photoconductor that demonstrates increased conductivity during its exposure to infrared radiation.

The photographic recording of images on a medium sensitive to infrared radiation, using a source capable of emitting in the infrared and a filter that transmits only infrared radiation.

Photographic recording that uses infrared radiation as the light source to form an image of a microscopic object and a system of lenses and objectives that are transparent to the radiation. The image...

An optical component coated to reflect infrared radiation. Gold, silver and aluminum are typical coating materials.

A spectrophotometer having a prism or, more frequently, a grating for the study and recording of infrared spectra. It usually consists of a radiation source such as a Nernst glower, a monochromator,...

The measurement of the ability of matter to absorb, transmit or reflect infrared radiation and the relating of the resultant data to chemical structure.

Used to detect radiation from the infrared region. The functional process includes absorption of infrared radiation, which causes a temperature change, consequently altering the physical properties...

A thermistor that uses a semiconductor that is sensitive to infrared radiation to measure the radiation's intensity.

A vidicon that has a photoconductive surface that can be excited by infrared radiation.

Infrared (IR) refers to the region of the electromagnetic spectrum with wavelengths longer than those of visible light, but shorter than those of microwaves. The infrared spectrum spans wavelengths...

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...

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...

With respect to laser radiation, the subjection of the human eye to all or a portion of the laser beam.

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....

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.

Collisional absorption of energy that occurs in inertial confinement fusion systems when hydrodynamic expansion of the plasma causes an electron passing through the field of an ion to absorb...

A filter that transmits infrared and ultraviolet but is opaque to visible radiation.

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,...

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...