Fiber Optic Glossary

• E O
  Abbreviation for electrical-to-optical converter.
• E2000 Connector
  The E2000/LX-5 is like a LC but with a shutter over the end of the fiber.
• Eccentricity
  In the tolerancing of optical elements, the displacement of the optical axis from the mechanical axis.
• EDFA
  Erbium-doped fiber amplifier, an all optical amplifier for 1550 nm SM transmission systems.
• EDFA Erbium Doped Fiber Amplifier
  An optical amplifier that boosts all channels in the optical signal at the same time.
• Edge Emitting Diode E LED
  A LED that emits from the edge of the semiconductor chip, producing higher power and narrower spectral width.
• Edge Emitting Laser
  A semiconductor laser that emits light in the plane of its junction from the edge of the chip.
• Effective Area
  The area of a single-mode fiber that carries the light.
• Effective Cross Sections
  A modified type of transition cross sections which apply to optical transitions between Stark level manifolds.
• Effective Mode Area
  A quantitative measure of the area which a waveguide or fiber mode effectively covers in the transverse dimensions.
• Effective Mode Volume
  For an optical fiber, the square of the product of the diameter of the near-field pattern and the sine of...
• Effective Numerical Aperture
  The real numerical aperture (NA) of a fiber when the computed NA is not valid because of change in the...
• Effective Refractive Index
  A number quantifying the phase delay per unit length in a waveguide relative to the phase delay in vacuum.
• Efficiency
  A measure of the fraction of the input energy that is converted into output energy. Depending on the context, the writer/speaker...
• EGA
  Abbreviation for enhanced graphics adapter. A medium-resolution color standard for computer monitors.
• EIA
  An acronym for Electronic Industries Alliance.
• Elasto Optic Effect
  A change in the refractive index of an optical fiber caused by variation in the length of the fiber core...
• Electric CO Laser
  An electrically excited laser having carbon monoxide as the lasing material and in which lasing occurs in a partial inversion...
• Electric Dichroism Spectroscopy
  The use of a krypton laser system for the measurement of small molecules aligned by an electric field, by analyzing...
• Electrical Length
  Of a transmission medium, its length expressed as a multiple or submultiple of the wavelength of a periodic electromagnetic or...
• Electro Absorption Modulated Laser
  Has integrated CW laser with EA modulator on the same semiconductor chip.
• Electro Absorption Modulator
  A semiconductor diode reverse-modulated so it modulates light passing through it.
• Electro Optic Deflection
  The effect whereby a light beam is deflected by a birefringent prism when its polarization is changed by voltage applied...
• Electro Optic Effect
  The phenomenon that the refractive index of a material can be modified with an electric field.
• Electro Optic Modulators
  Optical modulators based on the electro-optic effect.
• Electro Optic Sampling
  An optical sampling technique based on the electro-optic effect.
• Electroabsorption Modulators
  Optical modulators based on the Franz–Keldysh effect.
• Electroluminescence
  The nonthermal conversion of electrical energy into light in a liquid or solid substance. The photon emission resulting from electron-hole...
• Electromagnetic Interference
  Any electrical or electromagnetic interference that causes undesirable response, degradation or failure in electronic equipment. Optical fibers neither emit nor receive...
• Electromagnetic Pulse
  A burst of electromagnetic radiation that creates electric and magnetic fields that may couple with electrical/electronic systems to produce damaging...
• Electromagnetic Radiation
  Waves made up of oscillating electrical and magnetic fields perpendicular to one another and traveling at the speed of light....
• Electromagnetic Spectrum
  The range of frequencies and wavelengths emitted by atomic systems.
• Electromagnetic Wave
  A disturbance, which propagates outward from an electric charge, which oscil lates or is accelerated. Includes radio waves; X-rays; gamma rays;...
• Electron
  A particle of matter that affects electricity and electrical current.
• Electron Beam
  A stream of electrons emitted by a single source that move in the same direction and at the same...
• Electron Device
  Any device in which the passage of electrons through a vacuum, gas or semiconductor is the principal means of...
• Electron Microscope
  A device utilizing an electron beam for the observation and recording of submicroscopic samples with the aid of photographic emulsions or...
• Electron Mirror
  An electron instrument used to reflect an electron beam totally.
• Electronic Band Edge
  The point at which short-wavelength transmission is cut off.
• Electronic Dispersion Compensation
  A method for mitigating the effects of chromatic dispersion in fiber optic communication links with electronic components in the...
• Electronically Controlled Coupling
  The use of an electric field or signal to couple a lightwave from one dielectric waveguide into another dielectric...
• Electrostatic Lens
  The electrical distribution that serves to influence an electron beam in the same way that an optical lens affects a light...
• Electrostatic Printer
  An instrument used to print an optical image on a specially treated paper. Light and dark portions of the original image...
• ELED
  Abbreviation for edge-emitting LED.
• Ellipticity
  Describes the fact that the core or cladding may be elliptical rather than circular.
• EM
  Abbreviation for electromagnetic.
• Embedded Laser
  The laser inside an enclosed laser device. Usually, an embedded laser is a laser that exceeds its MPE but is...
• Emergent Ray
  In optics, the light ray leaving a medium in contrast to the entering or incident ray.
• 
  EMI
  An abbreviation for electromagnetic interference. EMI is the interference in signal transmission or reception caused by the radiation of electrical...
• Emission
  Act of giving off radiant energy by an atom or molecule.
• Emitter
  Term used for a light source.
• Encapsulation
  The provision of end-to-end support of communication using a network protocol X across a network which only supports protocol Y by...
• Enclosed Laser Device
  A laser or laser system positioned within an enclosure to prevent dangerous optical radiation from leaving the enclosure.
• Enclosure
  A cabinet used to organize and enclose cable terminations and splices for use within main equipment rooms, entrance facilities, main...
• Encoding
  A means of combining clock and data information into a self synchronizing stream of signals.
• 
  End Face
  Term often used to describe the end of a ferrule. The end face is finished or polished to have a...
• End Finish
  For an optical fiber, the optical quality of the surface at the end of the fiber.
• End Fire Coupling
  Method of coupling two waveguides for optical fibers or integrated optical circuits by butting the two up against one...
• End of Bandwidth
  Defined by data arriving out of order in regards to its time domain.
• End Pumping
  A technique of optically pumping a laser medium in a direction along the laser beam.
• End Separation
  The distance between the ends of two joined fiber optic cables. End separation causes an extrinsic loss that depends on the...
• End Separation Loss
  The optical power loss caused by distance between the end of a fiber and a source, detector, or another fiber.
• End to End Loss
  The optical loss on an installed fiber optic cable data link path. This loss consists of the loss due to...
• 
  Endoscope
  A medical instrument used to view inside the human body by inserting the instrument into a natural or created aperture....
• Endscope
  A fiber-optic bundle used for imaging and viewing inside the human body.
• Energy
  Total amount of power emitted by the laser.
• Energy Level
  Discrete energy states that an electron in orbit around an atom is allowed to have. Electrons may jump to a higher...
• Energy Sharing Laser
  A laser that distributes its output power among two, three or four optical fibers simultaneously.
• Energy Source
  High voltage electricity, radio waves, flashes of light, or another laser used to excite the laser medium.
• Energy Transfer
  The phenomenon that dopant ions in laser-active media can exchange excitation energy among each other.
• ENG
  Abbreviation for Electronic News gathering.
• Enhanced Pulsing
  A type of laser pulsing with high laser power at the beginning of the pulse.
• Enhancement Cavities
  Optical cavities for exploiting the resonant enhancement of the power of circulating light.
• Environmental sealing
  Designed in a connector using grommets, interfacial seals, peripheral seals, gaskets or potting material to keep contaminants such as dirt...
• Epoxy
  A thermosetting resin used to secure the fiber with the connector ferrule.
• Epoxy Connector
  A type of fiber optic connector that is terminated onto a cable with use of epoxy to perform a...
• Equalibrium Length
  For a specific excitation condition, the length of multimode optical fiber necessary to attain equilibrium mode distribution.
• Equilibrium Modal Distribution EMD
  Steady state modal distribution in multimode fiber, achieved some distance from the source, where the relative power in the modes...
• Equilibrium Mode Distribution (EMD)
  The steady modal state of a multimode fiber in which the relative power distribution among modes is independent of fiber...
• Equilibrium Mode Simulator
  For an optical fiber, a device or optical system used to create an approximation of the equilibrium mode distribution.
• Erbium
  Optical fibers are sometimes doped with the rare earth element, erbium, which can amplify light in the 1550 nm region...
• Erbium Doped Fiber Amplifier
  A type of fiber optic cable that amplifies 1550 nm optical signals when pumped with a 980-1480 nm light source.
• Erbium Doped Fiber Amplifier (EDFA)
  Optical fibers doped with the rare earth element, erbium, which can amplify light in the 1550 nm region when pumped...
• Erbium Doped Gain Media
  Laser gain media doped with erbium ions.
• Erbium Doped Waveguide Amplifier
  An optical amplifier similar to an EDFA, but derives a higher gain through a small waveguide rather than several meters...
• Error Correction
  In digital transmission systems, a scheme that adds overhead to the data to permit a certain level of errors to...
• Error Detection
  Checking for errors in data transmission. A calculation is made on the data being sent and the results are sent along...
• ESCON
  IBM standard for connecting peripherals to a computer over fiber optics. Acronym for Enterprise System Connection.
• ESKA
  Trade mark of plastic fiber optic cable manufactured by Mitsubishi Rayon Corp.
• Etalon
  Also Fabry-Perot Interferometer. Frequency tuning device that exploits the properties of interference between two adjacent flat, parallel surfaces.
• Ethernet
  1. A network of high-speed transmission cables and software. 2. A 10 Mbit/sec Carrier Sense Multiple Access with Collision Detection (CSMA/CD)...
• Ethernet Bridge Connectivity
  Used to connect two or more networks.
• Ethernet Converted to Fiber
  A 10 Mbit/sec CSMA/CD standard, converted to fiber optics.
• Ethernet Standards
  Not all Ethernet and IEEE 802.3 standards are identical. In fact, in some instances, there are enough differences in Ethernet standards...
• Evanescent Field
  In a waveguide, a time-varying field having an amplitude that decreases monotonically as a function of transverse radial distance from...
• Evanescent Wave
  Guided light waves that extend beyond the boundary of a fiber core into the cladding. Evanescent waves can transfer energy...
• Excess Loss
  The amount of light lost in a coupler, beyond that inherent in the splitting to multiple output fibers.
• Excess Noise Factor
  A factor, F, indicating the increase in shot noise in an avalanche photodiode as compared with the ideal multiplier, which...
• Excimer Lasers
  Lasers where optical amplification occurs in a plasma containing excited dimers with an anti-binding electronic ground state.
• Excited State
  Atom with an electron in a higher energy level than it normally occupies.

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