Views: 0 Author: Site Editor Publish Time: 2023-03-13 Origin: Site
From backbone, metropolitan area network, access network to LAN, the distance requirement of optical fiber is becoming shorter and shorter.
The performance of optical fiber is no longer important. The dispersion is larger and the loss is smaller. Because the transmission distance is shorter, it is acceptable.
On the contrary, low-cost light sources are attracting more and more attention. LED and VCSEL are much cheaper than FP, DFB and EDFA.
LED is considered in the first generation of LAN, which is old and cheap. Even the light spot is big and the light source of VCSEL is big, so multimode fiber has been studied a lot in 80-2000, with a diameter of 62.5 and 50 microns.
Today, let's talk about multimode fiber. At that time, the research was mainly used for LAN optical transmission (now it is extended to be used in data center)
Single-mode fiber has limited transmission mode of light, small dispersion, high requirements for light source, and long transmission distance
Multi-mode fiber, the mode of light is random, the dispersion is large, the requirements for light source are low, and the transmission is not far
