Document Type


Publication Date



In this work, we present an experimental demonstration of our previously published modeling work on reflective long period grating (LPG). To provide the practical realization of the modeling work, we coat a long segment of fiber both in the tail length and the end facet beyond the gratings with silver to invert the transmission mode LPG to reflection mode LPG. We then measure the LPG characteristics in both the transmission and reflection mode and validate our findings from modeling work. We further build temperature and refractive index (RI) sensors and demonstrate temperature sensing from 21 °C to 191 °C with similar temperature sensitivity coefficients of 54.4 ± 2.9 pm/°C and 53.2 ± 2.6 pm/°C for transmission and reflection mode LPG, respectively whereas same RI sensitivity coefficient of 370 ± 2.2 nm/RIU.