Graded-Index: Fiber optic cable design in which the refractive index of the core is lower toward the outside of the fiber core and increased toward the center of the core; thus, light rays are focused inward which allows them to travel faster in the lower index of refraction region. This type of fiber provides higher bandwidth capabilities for multimode fiber transmission.
Wavelength: The distance between two successive points of an electromagnetic waveform, usually measured in nanometers (nm).
LASER Diode: Light Amplification by Stimulated Emission of Radiation. An electro-optic device that produces coherent light within a narrow range of wavelengths, typically centered around 780 nm, 1310 nm, or 1550 nm. Lasers with wavelengths centered around 780 nm are commonly referred to as CD Lasers.
Light Emitting Diode (LED): A semiconductor device used to transmit light into a fiber in response to an electrical signal. It typically has a broad spectral width.
Mode: A term used to describe an independent light path through a fiber, as in multimode or singlemode.
Multimode Fiber (MM): An optical waveguide in which light travels in multiple modes. Typical core/cladding size is 62.5µm /125µm (measured in micrometers).
Multiplex: Combining two or more signals into a single bit stream that can be individually recovered.
PVC: Abbreviation used to denote polyvinyl-chloride. A type of plastic material used for cable jacketing. Typically used in flame-retardant cables.
Plenum: An air-handling space such as that found above drop-ceiling tiles or in raised floors. Also, a fire-code rating for indoor cable.
Radio Frequency Interference (RFI): Electromagnetic radiation which is emitted by electrical circuits carrying rapidly changing signals, as a by-product of their normal operation, and which causes unwanted signals (interference or noise) to be induced in other circuits.
Singlemode Fiber (SM): An optical waveguide (or fiber) in which the signal travels in one mode. The fiber has a small core diameter, typically 8.3 µm.
Buddy Oliver is a recording engineer with degree in audio engineering. He’s also director, professional audio for FiberPlex as well as the company’s lead engineer for the Light Viper pro audio product line.