| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical amplifier which can make wavelength dependency of the gain of an EDF in a so-called a non-temperature-control stimulation light source unit. <P>SOLUTION: The optical amplifier 21 is equipped with the EDF28, a light source unit 1 having a semiconductor laser element 5 emitting stimulation light and a housing 14 storing it, and an optical multiplexer 26 having an input 37 optically coupled with the light source unit 1, an input 38 for receiving signal light, and an output 39 for providing the stimulation light and signal light for the EDF28; and the semiconductor laser element 5 has an active layer 15 which contains a compound semiconductor between clad layers 16 and 17 including mutually different conductivity compound semiconductors and is so constituted that the oscillation wavelength of the semiconductor laser element is 440 to 1470 nm at 20°C. In this case, the variation in the gain of the EDF28 to the oscillation wavelength can be made sufficiently small and NF can be made sufficiently small. <P>COPYRIGHT: (C)2003,JPO |
