Fiber Optic Glossary

• T Carrier
  A system transmitting signals at one of the standard levels in the North American digital hierarchy.
• T Coupler
  A passive optical coupler having three ports (three fibers).
• Tachyons
  Tachyons are hypothetical particles, traveling with velocities above the vacuum velocity of light. Formally, such particles would appear to be...
• Talkset Fiber Optic
  A communication device that allows conversation over unused fibers.
• Tap
  To draw energy from a circuit.
• Tap Loss
  In a fiber optic coupler, the ratio of power at the tap port to the power at the input...
• Tap Loss
  In a fiber optic coupler, the ratio of power at the tap port to the power at the input...
• Tap Port
  In a fiber optic cable coupler in which the splitting ratio between output ports is not equal it is the...
• Tap Port
  In a coupler in which the splitting ratio between output pods is not equal, the output port containing the lesser...
• Taper
  A section of optical fiber or a micro-component that has a continuously changing outer dimension, along its length, from one...
• Tapered Fiber
  An optical fiber in which the cross section, i.e., cross-sectional diameter or area, varies, i.e., increases or decreases, monotonically with...
• TAXI
  Transparent synchronous transmitter-receiver interface.
• TCP IP
  A protocol specification that conforms to the latest DOD ARPANET standard. The TCP/IP protocol module corresponds to layers three and four...
• TDDM
  An abbreviation for time division demultiplexing.
• TDM
  An abbreviation for time division multiplexing.
• TEC
  Abbreviation for thermoelectric cooler. A device used to dissipate heat in electronic assemblies.
• Tee Coupler
  A three-port optical coupler.
• Tee Coupler
  A Three-Pod Optical Coupler
• Telecom Fibers
  Telecom fibers are optical fibers which are used in optical fiber communications.
• Telecommunications Management Network
  A network that interfaces with a telecommunications network at several points in order to receive information from, and to control...
• TEM00
  A Gaussian-curve mode.
• TEM01
  Divided into two equal beams for special applications.
• Temporal Walk Off
  Loss of temporal overlap of pulses caused by group velocity mismatch.
• Tensile Strength
  The strength of an optical fiber when placed in tension. Usually given in units of kilo-pounds per square inch...
• Tensile test
  Pull test – a controlled pull test on the contact crimp joint to determine its mechanical strength.
• Terminating
  Terminating a fiber is accomplished through preparing the fiber for connection to another fiber or device such as a connector....
• Termination
  Termination of fiber optics is the process of cutting and adding a connector at the end of the fiber, making...
• Termination and Splicing
  Termination and splicing equipment for fiber optics include tools or kits for cutting, finishing, positioning, aligning and joining fiber optic...
• Termini
  More than 1 terminus. See Terminus[http://www.timbercon.com/Terminus.html].
• 
  Terminus
  A device used to terminate, position, and hold an optical fiber within a connector.
• Test Cable
  A short single fiber jumper cable with connectors on both ends used for testing. This cable must be made of...
• Test Kit
  A kit of fiber optic instruments, typically including a power meter, source and test accessories used for measuring loss and...
• Test SFP
  Test port operations in hub, board, system and other applications with SFP Electrical Loopbacks from Timbercon.
• Test Source
  A laser diode or LED used to inject an optical signal into fiber for testing loss of the fiber or...
• TFF
  An abbreviation for thin-film filter.
• 
  TFOCA
  TFOCA stands for Tactical Fiber Optic Cable Assembly. They are developed to be extremely strong and rugged so as to...
• 
  TFOCA II Connectors
  TFOCA II ®[http://www.timbercon.com/About-Timbercon/trademarks.html] Connectors are military style fiber optic connectors designed for rugged use in harsh environments. TFOCA stands for Tactical Fiber Optic...
• Thermal Lensing
  Lensing effect induced by temperature gradients.
• Thermal Noise
  Noise resulting from thermally induced random fluctuation in current in the receiver's load resistance.
• Thermal Stability
  A measure of the insertion loss variation as the device undergoes various environmental changes.
• Thermal Stability
  A measure of insertion loss variation as the device undergoes various environmental changes.
• Thermistor
  A temperature-sensing element composed of sintered semiconductor material, which exhibits a large change in resistance proportional to a small change...
• Thermocouple contact
  A contact made of special material, used in connectors in high temperature applications as a means of measuring temperature electrically.Materials...
• Thermoelectric Cooler
  s a semiconductor heat pump which ulilizes the Peltier effect. The TEC operates as follows: For ambient temperature greater than...
• Thermooptic Switches
  Optical switches controlled by temperature-induced changes in refractive index.
• Thick Wall Tubing
  Quartz or silica tubing which has a large OD to ID ratio. It can have a very small inside diameter (e.g.,...
• Thin Disk Lasers
  Solid state bulk lasers having a very thin disk of laser-active material as gain medium.
• Thin Film Optical Waveguide
  A slab-dielectric waveguide that consists of multilayered films of material of different optical characteristics, is capable of guiding an optical...
• Third Order Dispersion
  Dispersion related to a third-order dependence of the phase change on the frequency offset.
• Third Window
  Of silica-based optical fibers, the transmission window at approximately 1.55 m. Note: The third window is the minimum-loss window in...
• Threaded coupling
  A means of coupling a mating pair of connectors by engaging threads on the exterior of a receptacle with interior...
• Threshold Current
  The forward bias current at which the diode starts to emit stimulated emission (thus becoming a laser, or lasing). I...
• Threshold Current
  The minimum current needed to sustain laser action in a diode laser.
• Threshold Power
  The optical output power at threshold current.
• Threshold Pump Power
  The pump power for which the laser threshold is reached.
• Thresholdless Lasers
  Lasers with a threshold power which is virtually zero.
• Throughput Loss
  In a fiber optic cable coupler it is the ratio of power at the throughput port to power at the...
• TIA
  An acronym for Telecommunications Industry Association.
• TICL
  Abbreviation for temperature induced cable loss. Optical loss as a result of extreme temperatures outside a fiber optic cable’s environmental...
• Tight Buffer
  Protective material surrounding the cladding of an optical fiber that allows the fiber no play within it.
• Tight Buffer
  Type of cable construction whereby each glass fiber is tightly buffered by a protective thermoplastic coating to a diameter of...
• Tight Buffered Cable
  A protective coating extruded tightly over fiber for mechanical and environmental protection. The coating material is either nylon or PVC....
• Time Bandwidth Product
  Product of temporal and spectral width of a pulse.
• Time Division Multiplexing
  A multiplexing technique operating in the time domain.
• Time Domain Reflectometer
  See Optical Time-Domain Reflectometer (OTDR).
• Time of Flight Measurements
  Time-of-flight measurements are often used for measurement of some distance, e.g. with a laser range finder, used e.g. in an...
• Time To Failure
  This term applies only to gradual failures. In general, the characteristics (e.g. optical power, threshold current, operating current) of the...
• Time-Division Multiplexing (TDM)
  A transmission technique whereby several low-speed channels are multiplexed into a high-speed channel for transmission.
• Timing Jitter
  Fluctuations of the temporal positions of pulses.
• Timing Phase
  A phase reflecting timing deviations by relating them to the pulse period.
• Titanium Sapphire Lasers
  Lasers based on a Ti:sapphire gain medium.
• Token Ring
  The IEEE 802.5 Token Ring protocol provides a deterministic method of shared media access. Two standards exist, one with 4-Mbit/sec operation...
• Tolerance
  Amount of variance from a standard that is allowed.
• Topology
  The manner in which the nodes or stations of a network are connected.
• Topology
  The physical layout of a network
• Total Bandwidth
  The combined modal and chromatic bandwidth.
• 
  Total Internal Reflection
  Total internal reflection is an optical phenomenon that occurs when a ray of light strikes a medium boundary at an...
• Total Internal Reflection
  Total reflection of light back into a material when it strikes the interface of a material having a lower index...
• Tracking Error
  s a ratio of fiber-coupled power at two different case temperatures measured in dB.
• Transaction Monitors
  Systems that control access to databases to ensure consistency, integrity and recovery. A new generation of products that perform this function...
• Transceiver
  An instrument or system capable of both transmitting and receiving a signal.
• Transceiver
  An electronic device which has both transmit and receive capabilities.
• Transducer
  A device for converting energy from one form to another, such as optical energy to electrical energy.
• Transform Limit
  The minimum pulse duration possible for a given optical spectrum.
• Transistor
• Transition Metal Doped Gain Media
  Lasers based on gain media which are doped with transition metal ions.
• Transmission
  In optics, the passage of radiant energy (light) through a medium.
• Transmission Loss
  Loss associated with light attenuation during transmission.
• Transmission Loss
  Total loss encountered in transmission through a system.
• Transmission Loss
  Total loss encountered in transmission through a system.
• Transmission Media
  Anything such as wire, coaxial cable, fiber optics, air, or vacuum, that is being used to carry an electrical signal which...
• Transmittance
  The ratio of transmitted radiant energy to incident radiant energy, or the fraction of light that passes through a...
• Transmitter
  In fiber optic communications, a light source whose beam can be modulated and sent along an optical fiber, and the...
• Transmitter
  An electronic package which converts an electrical signal to an optical signal.
• Transmitter Central Wavelength
  In optical communication, the total allowed range of transmitter central wavelengths caused by the combined worst-case variations due to manufacturing,...
• Transmitter XMTR
  A device which includes a LED or laser source and signal conditioning electronics that is used to inject a signal...
• Transparent
  Describes the operation of a network such that a user is unaware that a service is being provided by the network;...
• Transparent Network
  A fiber-optic network that is entirely light based with optical switches and other optical-only devices.
• Transponder
  Also called Transceiver with MUX and DEMUX. An integrated device that integrates laser source, detector, MUX and DEMUX in one...
• Transport Layer
  The fourth layer of the OSI model of data communications. High level quality control (error checking) and some alternate routing is...

Suggestions?
The Timbercon Fiber Optic Glossary continues to expand and improve. If you have suggestions for improvement, we would enjoy hearing from you. Please contact the webmaster here.