| 摘要 |
PROBLEM TO BE SOLVED: To reduce the size by providing means for inputting/outputting a signal light and an amplified signal light at one end of an optical amplifying medium having the other end arranged with an exciting light source, and entering a signal light to the optical amplifying medium through an optical filter transmitting only an exciting light from the other end and reflecting the signal light thereby eliminating a conventional optical multiplexer. SOLUTION: A signal light enters from the optical I/O terminal 1 of an optical circulator 101 into an erbium added optical fiber 103 connected with an optical I/O terminal 2. An exciting light from an exciting light source 107 transmits through a grating fiber 105 and enters into the erbium added optical fiber 103 thus amplifying the signal light optically. The signal light is reflected on a grating fiber 10 to pass through the erbium added optical fiber 103 again and to enter into the optical I/O terminal 2 of the optical circulator 101 thus outputting an amplified signal light from an optical I/O terminal 3. This arrangement eliminates the need of optical multiplexer. |
