| 摘要 |
<p>An optical fiber amplifier comprising, in addition to an amplification medium for amplifying signal light, an excitation light source which generates excitation light to be launched into the amplification medium and photocoupling means for coupling the excitation light to the amplification medium, modulating means for amplitude-modulating the excitation light, sub-signal generating means for generating a sub-signal which is superimposed on the excitation light for amplitude modulation and a frequency filter for converting the frequency characteristic of the sub-signal to input it to the modulating means, for superimposing the sub-signal due to change in gain of the amplification medium for pulse modulation of the excitation light. High-frequency components of the sub-signal is previously emphasized through the frequency filter, and the excitation light is amplitude-modulated by the sub-signal with the emphasized high-frequency components, to superimpose the satisfactory, waveform distortion-free sub-signal on the signal light. <IMAGE></p> |
