This part of IEC 61290 applies to all commercially available optical amplifiers (OAs) and optically amplified modules. It applies to OAs using optical fibre amplifiers (OFAs) based on either rare-earth doped fibres or on the Raman effect, semiconductor OAs (SOAs) and planar optical waveguide amplifiers (POWAs). The object of this standard is to establish uniform requirements for accurate and reliable measurements, by means of the optical spectrum analyzer (OSA) test method, of the following OA parameters, as defined in IEC 61291-1: a) nominal output signal power; b) gain; c) polarization-dependent gain (PDG); d) maximum output signal power; e) maximum total output power. In addition, this standard provides the test method of: f) gain ripple (for SOAs). NOTE All numerical values followed by (! ) are suggested values for which the measurement is assured. The object of this standard is specifically directed to single-channel amplifiers. Test methods for multichannel amplifiers are standardized in the IEC 61290-10 series [1]2.