Author biographies xiii CHAPTER 5. DYNAMIC AND STATIC GAIN CHANGES OF OPTICAL AMPLIFIERS AT ROADM NODES (ETSUKO ISHIKAWA, SETSUHISA TANABE, MASATO NISHIHARA, AND YOUICHI AKASAKA) Etsuko Ishikawa Is currently director of Research at Fujitsu Ltd. Her achievements include development of S-band optical amplifier using silica-based erbium doped fiber; research in spectral hole burning mechanism in erbium doped fiber amplifier. Ishikawa.etsuko@jp.fujitsu.com Setsuhisa Tanabe received the BS, MS, and PhD degrees in material chemistry from Kyoto University, Japan, in 1986, 1988, and 1993. He became an Assistant Professor of Kyoto University, where he was promoted to a Full Professor in 2008 at Graduate School of Human and Environmental Studies. He is the author of more than 100 original papers, 22 books, and 23 invited review papers. He is also the holder of 24 patents on rare-earth doped optical amplifiers and glass ceramic phosphors for solid-state lighting. stanabe@gls.mbox.media.kyoto-u.ac.jp