Akihiko Kasukawa, Toshikazu Mukaihara, Takeharu Yamaguchi, Jun'jiro Kikawa
Optical fiber communication systems using a WDM (wavelength division multiplexing) system are being introduced in long-haul networks to manage the explosive increase in transmission capacity. Erbium-doped fiber amplifier (EDFA) is one of the key components to support WDM systems. High power lasers emitting at both 980 nm and 1480 nm are essential for pumping sources for EDFA. In this paper, state-of-the-art high power pumping lasers are reviewed. Furukawa Electric has succeeded to release high performance and high reliable pumping lasers. In particular, ultra-high output power of 250 mW-1480 nm modules have been commercialized. These high output power laser modules are of great importance for Raman amplifiers as well as EDFA applications.