Patent ID: 7061667
Filing Date: 2006-06-13
Classification: H01S

Abstract:
1. An erbium doped fiber amplifier (EDFA), comprising: first and second amplifier stages, the first amplifier stage including a high power pump laser and an erbium doped fiber for generating amplified spontaneous emission (ASE) at a first wavelength band, and the second amplifier stage including an erbium doped fiber arranged to be pumped by the ASE from the first amplifier stage to generate gain in signal channels at a wavelength band longer than the first wavelength band, the second amplifier stage including a removable length of erbium doped fiber arranged as a plug-in unit and which is selectable to produce a required output power for a given input power and which has connectors at ends of the removable length of the fiber for connection to the amplifier.