Patent ID: 6377393
Filing Date: 2002-04-23
Classification: H04B

Abstract:
An optical amplifier apparatus comprising:an optical amplifier for optically amplifying first signal light inputted from an input port thereof and for outputting the first amplified signal light from an output port thereof; an optical circulator equipped with at least four ports through which light is inputted/outputted, in which light inputted from a first port thereof is outputted from another port thereof; a first optical isolator arranged at a pre-stage of said optical amplifier; and a second optical isolator arranged at a post-stage of said optical amplifier, wherein said input port of the optical amplifier is connected to the second port of said four ports, said output port of the optical amplifier is connected to said third port, the first signal light is entered to the first port for outputting light to said second port, second signal light is entered to the fourth port for outputting the light inputted to the third port, and said second signal light is outputted from said first port.