What is optical fiber’s core size?
Core size is the physical dimension of the fiber core. The core’s size has a big impact on coupling light into a fiber. The core’s size has to be at least as big as the light source in order to collect light efficiently. If the light source is larger than the fiber core, much of its power goes into the fiber cladding and escape quickly. Multimode fibers comes in a variety of core sizes between 7um and 3mm, of which the most usual are 50um, 62.5um, 100um and 200um. The industry standard for data communications is now 50um and 62.5um multimode using silica glass fibers. Single mode silica glass fibers typical has a 8.3um core size. Telecommunications uses exclusively single mode glass fibers, though data communications also shows a slow but steady adoption of single mode glass fibers. For plastic optical fibers, the fiber core size ranges from 0.25mm to 3mm of which 1mm is the most popular.
