An OTDR is a fiber tester used to test the characteristics of optical communication networks. An OTDR is designed to detect, locate, and measure events anywhere on a fiber link. An OTDR only requires access to one end of the link and works like a one-dimensional radar system. By providing a graphical trace feature of the fiber under test, the user can get a graphical display of the entire fiber link.
Items measured by an OTDR
By injecting a light pulse into one end of the fiber and analyzing the backscattered and reflected signals, an OTDR can measure:
Optical path
· To components: splices, connectors, splitters, multiplexers…
· To faults
· To the end of the fiber
Loss, optical return loss (ORL)/reflectivity
· Splice and connector loss
· Link or segment optical return loss test