| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical relay amplifier reduced in noise figure. SOLUTION: This optical relay amplifier consists of an optical circulator 22, that outputs an input from a terminal 22a to a terminal 22b and outputs an input from the terminal 22b to a terminal 22c, a fiber Bragg grating 25 that reflects a light of the wavelength of monitor light, a fiber amplifier 26, an optical filter 23 that interrupts a spontaneously emitted light of the fiber amplifier, and a monitor light OE element 24. The terminal 22a of the optical circulator is used for an input terminal of the optical relay amplifier, the terminal 22b of the optical circulator is connected to the input terminal of the fiber Bragg grating 25, an output terminal of the fiber Bragg grating 25 is connected to the input terminal of the fiber amplifier 26, the output terminal of the fiber amplifier 26 is used for an output terminal of the optical relay amplifier and the terminal 22c of the optical circulator is connected to an input terminal of the optical filter 23, and an output terminal of the optical filter 23 is connected to the monitor light OE element 24. |
