Ask Bruno

Ask John Bruno

John shares his knowledge of fiber optics by answering your specific questions


When troubleshooting fiber optic systems, I spend a lot of time inspecting connector endfaces. What can you suggest to speed things along?

Bruno's Answer

A. Use a microscope with sufficient magnification. Although 100x may be okay for multimode fiber, I would use 200x or higher for singlemode fiber, which has a smaller core diameter and cannot easily be seen with just the 100x microscope. The increased magnification of the 200x is easier on the eyes and will enable you to detect problems quickly. Another way to speed up your inspections is to use a video microscope, which displays a large image of the endface on an LCD screen. FIS offers a battery-powered Portable Video Microscope that is great for field use. You can learn more about FIS' video microscope offerings here: