The mode dispersion is very small, which is suitable for long-distance communication, but there are also material dispersion and waveguide dispersion, so the single-mode fiber has higher requirements for the spectral width and stability of the light source, that is, the spectral width should be narrow and the stability should be good.
Characteristic
The single-mode fiber has a core diameter of 10micron, which can allow the transmission of single-mode light beam, and can reduce the limitation of frequency width and mode dispersion. However, because the core diameter of single-mode fiber is too small, it is difficult to control the transmission of light beam, so an extremely expensive laser is needed as the light source. The main limitation of single-mode optical cable is the material dispersion, and the single-mode optical cable can obtain high frequency width mainly by using laser, while LED will emit A large number of light sources with different frequency and width are put in, so the material dispersion requirements are very important.
Compared with multimode fiber, single-mode fiber can support longer transmission distance. In 100Mbps Ethernet or 1g gigabit network, single-mode fiber can support more than 5000m transmission distance.
From the cost point of view, because the optical terminal is very expensive, the cost of using single-mode fiber is higher than that of multimode fiber cable. Single mode fiber is used in long-distance and large capacity optical fiber communication system, optical fiber local area network and various optical fiber sensors.
Choice
The nominal core diameter of single-mode fiber is (8~10) μ m/125 μ m. Specifications (number of cores) include 2, 4, 6, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, 96 cores, etc. The cable outer sheath materials are common type, common flame retardant, low smoke and halogen-free type, low smoke and halogen-free flame retardant type.
When the user has confidentiality requirements for the system, and the signal is not allowed to be sent out, or the system transmission index cannot meet the requirements, shielded copper core twisted pair cable and shielded wiring equipment shall be used, or optical cable system shall be used
