Definitions: I

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

The ejecting of ions from the surface of a material.

A method of fabricating a graded-index optical waveguide by means of an ion exchange process.

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,...

Two oppositely charged particles.

A technique for improving the structure density of thin-film coatings by bombarding the growing film with accelerated ions of oxygen and argon. The kinetic energy then dissipates in the film, causing...

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 amount of energy required for a particular kind of atom to remove an electron to infinite distance. The ionization potential is usually expressed in volts.

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...

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

An electroradiographic process that uses ionization of air by x-rays as a basis for forming electrostatic images.

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.

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...

A system that transmits and receives identification codes to facilitate the discrimination between enemy and friend in a tactical situation.

The general term for the application of light to a subject. It should not be used in place of the specific quantity illuminance.

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

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...

In computer graphics, the coordinated two-dimensional or three-dimensional area of increased resolution where graphics entities may be defined. The screen represents a viewing window for this area,...

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.

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

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

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.

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.

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.

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

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

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.

A device used to accelerate the electrons in a free-electron laser by supplying electrical energy to the electron beam through a series of transformers.

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...

Inertial fusion energy (IFE) refers to a proposed method of generating electricity by harnessing the energy released from the fusion of light atomic nuclei, typically isotopes of hydrogen, through a...

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...

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...

The use of two lasers as a master-slave pair in order to control frequency and prevent chirp. When light from the master is injected into the slave, the slave becomes locked to the same frequency as...

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.

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...

The use of a small ultrastable master oscillator (a diode-pumped Nd:YAG laser) to achieve single-frequency operation of a large pulsed Nd:YAG host laser, providing improved bandwidth and temporal...

A process by which a plastic cell is molded around a glass lens or lenses to create a mount, eliminating the metal barrel and the need for glass-to-metal seals.

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.