Measurement of Active Optical Fibers

Abstract

Active optical fiber owns its special optical properties to laser-active dopants in fiber. This chapter presents key properties and their characterization, including measurement principles, experimental techniques, as well as test results, of active optical fiber. Firstly, the fundamental optical properties and relations between light and matter in active fiber are introduced, including Einstein relation, the absorption and emission cross sections, energy transfer, as well as up-conversion. Then the measurements of the absorption, emission, and gain are described.