First order optical differentiator based on an FBG in transmission

In this paper we experimentally demonstrate a first-order optical differentiator based on an FBG in transmission. In order to prove the concept, we characterized the FBG with an optical vector analyser, and performed an optical pulse differentiation experiment where the signals were characterized using an optical spectrum analyser (OSA) and a second harmonic generation (SHG) frequency resolved optical grating (FROG) system. We show that the resulting differentiated pulse is in very good agreement with the numerically predicted differentiated pulse, validating this simple and inexpensive solution for the fabrication of first-order optical differentiators.