Return Loss is a measure of the relative power reflected back from a splice, connection, or defect in the fiber. In the early days, this was a big problem. Lasers could be destabilized by power coming back at them, and analog video would suffer ghosts. This is largely a thing of the past, and measuring RL is something of a historical remnant. In fact – and it may be controversial to say this – measuring Return Loss is no longer critical.

Today, good (high) RL numbers are regarded as a mark of quality. If a connector shows poor RL, it may still perform adequately, but this indicates something is not quite right with the process. If you are not getting high RL measurements, I encourage you to investigate your production process. Also, it’s possible that good RL may contribute to long-term reliability, although I don’t have concrete evidence to support this.


READ THE BLOG: How to Accurately Measure IL/RL


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