Photonics Dictionary

The digitization process by which an image is manipulated to increase the amount of information perceivable by the human eye.

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 television camera tube that preceded the development of the vidicon tube and incorporated a method to separate reflected and scattered portions of the return beam so that only the scattered...

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...

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...

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 hologram in which the image of an object, or the object itself, is located near the hologram recording plane, for optimum image reconstruction. Because the images are close to the hologram plane,...

A measure of the closeness with which an optical image is capable of resembling the original object. The factors that affect image quality are lens aberrations, diffraction, dirt and stray light...

Filtering procedures aimed at estimating the original image by removing the blurring and noise suppression that occur during image processing.

Image segmentation is a fundamental process in computer vision and image processing that involves partitioning an image into multiple segments or regions based on certain criteria, such as color,...

An image signal processor (ISP) is a hardware component or subsystem in digital imaging devices responsible for capturing, processing, and enhancing images from a camera sensor. The ISP performs...

An eyepiece having a special prism arrangement linked to a micrometer screw to allow reading of the angular relations between the two prism segments to be varied. When the prism faces are parallel,...

A modified form of an image-retaining panel that can be used in subdued daylight. This is achieved by adding a layer of zinc oxide between the panel's phosphor layer and its rear electrode. The zinc...

A method used to compare two pictures of the same subject taken at different times. See image comparison.

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...

The processing of an image or portion of an image by transform coding and analysis. Fourier, Hadamand, Kronecker and Eigenvector transforms are applicable to image transformation.

Photogrammetric compensation for incidental camera movement (which prevents attainment of true vertical photographs) whereby the imagery is copied in an oblique plane camera system.

A thermoplastic or thermosetting material used to hold an object fixed and keep it from deterioration. In microcircuitry, the process of imbedding is known as potting.

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...

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

An oil required by oil-immersion objectives that is applied between the exterior of the objective lens and a cover glass or appropriate specimen.

A type of refractometer designed to measure the refractive indices of liquids. A section of the instrument is immersed into the sample being measured.

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...

Qualitatively, the inverse of the amount of velocity produced by the application of a sinusoidal force to a system; therefore, if velocity is high, impedance at that point is low. Quantitatively,...

An alien, electrically charged atomic system in a solid; an ion substituted for the constituent atom or ion in a crystal lattice, or located in an interstitial site in the crystal.

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 situ, from Latin meaning "in place," refers to a method or approach where measurements, observations, or experiments are conducted directly at the location of interest or within the natural...

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 formation of a hologram by single reference-beam interferences with waves that are diffracted or scattered from a small object.

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

An exposure meter designed to measure the light striking an object and used at a suitable location in a scene.

The presence, within the body of the glass, of extraneous or alien material. See seed; striae.

In optics, the term denoting the lack of a fixed phase relationship between two waves. If two incoherent waves are superimposed, interference effects cannot last longer than the individual coherent...

The production of holograms initially from either conventional photographs or incoherent optical equipment.

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

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

The ratio of the velocity of light in a vacuum to the velocity of light in a refractive material for a given wavelength.

In an optical waveguide, the refractive index as a function of radius.

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.

Generally, a rotatable table with scales marked in degrees. The fiducial marking also may be a vernier scale. The same scheme is applied to linear movement. Such devices are often applied to...

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 energy transition concerned with the combination of a photon and a phonon.

Indirect time-of-flight (iTOF) is a method used in 3D imaging and depth sensing to measure the distance to an object based on the time delay between the emission of a light pulse and the detection of...

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 gallium arsenide (InGaAs) is a semiconductor compound composed of indium (In), gallium (Ga), and arsenic (As). It belongs to the III-V group of semiconductors and is commonly used in...