8,726 terms
Photonics Dictionary
Ioffee barA fusion system conductor capable of carrying current in opposite directions in alternating time phases.
IOLintraoccular lens
IOLCintegrated optical logic circuit
ionAn atom that has gained or lost one or more electrons and, as a result, carries a negative or positive charge.
ion emissionThe ejecting of ions from the surface of a material.
ion exchange techniqueA method of fabricating a graded-index optical waveguide by means of an ion exchange process.
ion laserA 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 pairTwo oppositely charged particles.
ion-assisted depositionA 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 sputteringIon-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,...
ionic focusingAlso 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...
ionization chamberA 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.
ionization gaugeA 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...
ionization potentialThe 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.
ionization spectrometerAlso 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...
ionizing radiationGenerally, any radiation that can form ions, either directly or indirectly, while traveling through a substance.
ionographyAn electroradiographic process that uses ionization of air by x-rays as a basis for forming electrostatic images.
ionosphereThe 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.
IPindium phosphide
IPDimage photocounting distribution; interpupillary distance
IPPimaging photopolarimeter
IRinfrared
IRAMSinfrared automatic mass screening
IRASinfrared astronomy satellite
IRCCDinfrared charge-coupled device
IRCMinfrared countermeasure
IRCSDinfrared charge-swept device
IREinfrared endoscope; Institute of Radio Engineers
IREDinfrared-emitting diode
iridescenceThe rainbow exhibition of colors, usually caused by interference of light of different wavelengths reflected from superficial layers in the surface of a material.
IRISinfrared intelligent spectro-radiometer; infrared interferometer spectrometer
iris diaphragmA mechanical device designed to smoothly vary the effective diameter of a lens, thereby controlling the amount of light allowed through.
irisThe adjustable membrane located just in front of the crystalline lens within the eye. The iris gives the eye its color. See also iris diaphragm.
IRLDinfrared laser diode
IRMSinfrared measurement system
irradianceRadiant flux incident per unit area of a surface. Also called radiant flux density.
irradiated cross-linked polyolefinA thermosetting material used in the jacket of fiber optic cables.
irradiationApplication of radiation to an object.
IRSinertial reference system
IRSTinfrared search and track
ISAInstrument Society of America
ISDNintegrated services digital network
ISDPintegrated signal and data processor
Ishihara test -> color perception test equipmentEquipment for testing an observer's color vision. Some tests require the identification or ordering of colored samples. The commercially available examples include: the Ishihara plates, on which...
ISIinfrared signature imaging
ISITintensified silicon intensifier target
ISLintersatellite link
ISOInternational Standards Organization
isobarOne of a number of nuclides characterized by an identity between their mass numbers, but each having a different atomic number.
isocandela diagramIndication of emission brightness with degree of emission from an optical source.
Photonics Dictionary