Chromatic dispersion measurement of EDFA using optical sampling oscilloscope

Summary form only given. In this report, we directly measured relative group delay time of a highly Er-doped EDFA (Er-doped fibre amplifier). (MFD: 6.9 /spl mu/m, Er/sup 3+/ density: 1760 ppm, Al density: 13800 ppm, EDF length: 20 m) under 1480-nm pumping for the first time, to our knowledge, using an optical sampling oscilloscope and an optical short-pulse generator. We also derived its dispersion.