Infrared thermometry for breakage detection of optical fibers embedded in structures

We show that infrared thermometry can be used to detect a breakage point in an optical fiber embedded in a structure.Around the breakage point, incident light induces heat, which is detected using an infrared thermometer.By this method, we can obtain position information of a breakage point, including accurate information on where it is located in the actual structure, on a real-time basis.We experimentally show the practical usefulness of this method by detecting a breakage point in an optical fiber embedded in a composite structure comprising carbon fiber-reinforced plastics.