Development of an optical amplifier in phosphate glass for LIDAR applications Thanks to its solubility of laser-active rare earth ions, phosphate glass host represents a very promising alternative to the more traditional silica glass platform to develop compact active devices, such as lasers and amplifiers, expecially for LIDAR applications, where sometimes heavy and certainly not compact source solutions can represent a considerable limit. In this work there are reported the on-going activities, the solutions for the encountered problems and the recent results obtained during the development of an optical amplification bench designed for LIDAR applications.