1. In optical communications, a device that converts an electrical signal into an optical signal.
Note: The two most commonly used optical sources are light-emitting diodes (LEDs) and laser diodes.
2. Test equipment that generates a stable optical signal for the purpose of making optical transmission loss measurements. [After FAA]

By custom and practice, the electromagnetic spectrum between the wavelengths of the vacuum ultraviolet at
0. 001 m and the far infrared at 100 m.
Note: The term "optical spectrum" originally applied only to that region of the electromagnetic spectrum visible to the normal human eye, but is now considered to include all wavelengths between the shortest wavelengths of radio… (Read More →)

See directional coupler.

A switch that enables signals in optical fibers or integrated optical circuits (IOCs) to be selectively switched from one circuit to another.
Note 1: An optical switch may operate by (a) mechanical means such as physically shifting an optical fiber to drive one or more alternative fibers, or (b) electro-optic effects, magneto-optic effects, or other methods.
Note 2: Slow optical… (Read More →)

See power margin.

1. The product of the physical thickness of an isotropic optical element and its refractive index.
2. Of an optical system, the total optical path length through all elements.

An opto-electronic instrument used to characterize an optical fiber.
Note 1: An OTDR injects a series of optical pulses into the fiber under test. It also extracts, from the same end of the fiber, light that is scattered back and reflected back. The intensity of the return pulses is measured and integrated as a function of time, and is plotted… (Read More →)

See transmittance.

A device that accepts an electrical signal as its input, processes this signal, and uses it to modulate an opto-electronic device, such as an LED or an injection laser diode, to produce an optical signal capable of being transmitted via an optical transmission medium.

The use of optical fiber networks to transport data frames from multiple data sources over an optical wavelength channel.