Photonics Dictionary: I

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,...

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

Generally, the orientation of rays of light striking a surface.

Also referred to as image visibility, the contrast of an image is the variation in the intensity of an image formed by an optical system, where the image pixels are defined on a gray scale scheme of...

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...

In optics, the term image jump refers to a displacement or shift in the apparent position of an image when a change occurs in the optical system. This phenomenon is often observed in certain types of...

The active control of various aspects (optical element position, airspace thickness, etc.) of an optical system that compensates for unwanted movement of the image that is caused by mechanical and...

Photon flow created by imaging of light into a detector array; IPD is the electrical signal used by the image processor in a laser radar angular tracking system.

A plane in which an image is formed. A real image formed by a positive lens would be visible upon a screen located in this plane.

Any arrangement of a bundle of optical fibers that alters the shape of the image. For example, by systematic regulation of the spacing of the fibers from the entrance end to the exit end, a...

Term synonymous with refractive index liquid, but related more to tank or chamber immersion of crystals, fibers, lenses, photoelastic models, etc.

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

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...

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

A bundle of filaments of optical glass or other transparent materials that transmit only light, not optical images. The arrangement of the individual fibers in the bundle is not sufficiently regular...

A flaw deliberately introduced into an optical fiber to prepare it for cleaving.

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

A material, often a liquid or cement, whose refractive index is nearly equal to the fiber's core index, used to reduce Fresnel reflection from a fiber end face.

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...

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...

A device used in thin-film deposition; the material to be evaporated is placed in a crucible that is heated inductively by current passing through a coil around it.

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...

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,...

A filter exhibiting transparency, absorption or reflectance characteristics specifically for spectral control of wavelengths longer than 700 µm.

An image converter that produces a visible image based on the infrared emittance of the object. The infrared energy is focused on a photocathode that emits electrons. These are accelerated and...

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.

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...

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...

An infrared source combined with reflecting projection optics to illuminate a target making it visible when observed through an infrared viewing device.

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...

A semiconductor diode operating in either a coherent or incoherent mode that is used as a near-infrared or visible source in triggering light-activated devices.

The total optical power loss caused by the insertion of an optical component such as a connector, splice or coupler into a fiber optic system. See attenuation.