Updated: 04/26/2017 by Computer Hope

An optical time-domain reflectometer, or OTDR, is a device used to test optical fiber. It can be used to test for attenuation and overall fiber length, as well as accounting for splice and mated connector losses. OTDR helps to locate faults in the optical fiber and determine loss from optical return, which is light that is scattered or reflected back from various points in the fiber line.

Note: Using an OTDR, optical fiber can be characterized from the time it is manufactured to the time it is installed and spliced.

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