Both 50 micron and 62.5 micron fiber optic cables use an LED or laser light source. They are both multi-mode fiber. They are also used in the same networking applications. The main difference between the two is that 50 micron fiber can support 3 times the bandwidth of 62.5 micron fiber and 50 micron fiber also supports slightly longer cable runs than 62.5 micron cable. Single Mode is required for Distances over 600 meters (300 m for 10 Gbit/s).