6
•
Single mode fiber
—It has a core size of 10 µm or smaller, and has a lower modal dispersion. It
carries only a single ray of light. It is mostly used for communication over longer distances.
•
Multi-mode fiber
—It has a core size of 50 µm or 62.5 µm or higher, and has a higher modal
dispersion than single-mode optical fiber. It is mostly used for communication over shorter
distances.
Table 5 Allowed maximum tensile force and crush load
Period of force
Tensile load (N)
Crush load (N/mm)
Short period
150
500
Long term
80
100
Optical fiber cable
An optical fiber cable is a cable containing one or more optical fibers. The optical fiber elements are
typically individually coated with plastic layers and contained in a protective tube. Optical fiber cables
fall into single-mode and multi-mode.
Patch cord
A fiber that has connectors at both ends is called a patch cord. A patch cord connects one optical
device to another for signal routing. Patch cords fall into single-mode and multi-mode patch cords.
•
Single-mode patch cord
—The jacket is yellow. It permits transmission over longer distances.
•
Multi-mode patch cord
—The jacket is orange. It permits transmission over shorter distances.
Patch cords are classified into SC, LC, FC, and so on based on interface type. The length of a patch
cord can be 0.5 m (1.64 ft), 1 m (3.28 ft), 2 m (6.56 ft), 3 m (9.84 ft), 5 m (16.40 ft), 10 m (32.81 ft),
and so on.
Pigtail cord
A pigtail cord is an optical fiber that has an optical connector on one end and a length of exposed
fiber on the other. The end of the pigtail is fusion spliced to a fiber, connecting the fiber cable and
transceiver.
Pigtail cords fall into single-mode (yellow) and multi-mode (orange), and can also be classified into
SC, LC, FC, and so on based on interface type.
Fiber connector
Fiber connectors are indispensable passive components in an optical fiber communication system.
They allow the removable connection between optical channels, which makes the optical system
debugging and maintenance more convenient and the transit dispatching of the system more
flexible.
