What measurement tool to use after insertion loss for fiber optic?

After measuring insertion loss in fiber optic systems, the next important measurement tool to use is an Optical Time Domain Reflectometer (OTDR). The OTDR helps identify faults, splices, and connectors along the fiber link by providing a visual trace of the fiber's performance over distance. This tool is essential for troubleshooting and ensuring overall link quality. Additionally, it can also measure return loss, which is crucial for assessing the quality of connectors and splices.