Patent ID: 8364043

Claim:
A method of controlling a reflective semiconductor optical amplifier (RSOA), comprising: setting a threshold current, at which a light source starts to oscillate, to be constant regardless of a wavelength of seed light by controlling a driving temperature for driving a RSOA; and adjusting an optical characteristic, which is produced differently according to each wavelength of the seed light, to be constant by controlling a driving current, wherein the adjusting of the optical characteristic comprises: injecting seed light into a RSOA of an optical line terminal (OLT) for each wavelength and computing an optical power value according to a driving current for driving a RSOA of an optical network unit (ONU) or an optical network terminal (ONT); and setting the driving current to control an optical output characteristic, which is produced differently according to a wavelength of the seed light, to be constant using the computed optical power value.