| 摘要 |
PURPOSE:To eliminate a stop control of an exciting light source in an optical amplifier. CONSTITUTION:Applied light from an application light source 20 is synthesized to signal light by a wavelength filter 19. In this case, a wavelength band of the signal light is different from that of the applied light. By an erbium dope fiber 16 serving as an amplification medium, the synthesized signal light in which the signal light and the applied light are synthesized is amplified according to exciting light of a predetermined wavelength band and the amplified signal light is outputted. Then, the applied light from the amplified signal light is separated by the wavelength filter 19 and the output signal light according to the input signal light is outputted. By always applying the applied light in this manner, an unstable operation does not occur when the signal light is not received and a stop control of an exciting source 13 is eliminated. |
