| 摘要 |
<P>PROBLEM TO BE SOLVED: To control a signal light level per wavelength to a constant level irrelevantly to ASE light by preventing each signal light level of a wavelength multiplex signal from being relatively small at a reception terminal owing to accumulation of the ASE light. <P>SOLUTION: A light wavelength separating unit separates the output of an optical amplifying unit 11 into respective signal light beams, and electric signals corresponding to levels of the respective signal light beams are obtained by photoelectric converting units 16 to 18 and input to an arithmetic unit 19. The arithmetic unit 19 calculates a mean value from the levels of the respective signal light beams and the optical amplifying unit 11 is brought under feedback control through an output control unit 20 so that the mean value becomes constant. Output control is performed with a signal light level output from a light wavelength separating unit 12 which separates wavelengths other than signal light, so no influence of the ASE light level is exerted. <P>COPYRIGHT: (C)2008,JPO&INPIT |
