| 摘要 |
PROBLEM TO BE SOLVED: To make the output flat by using a gain-equalizing optical fiber also applicable as an amplifying optical fiber for equalizing the power of an output signal light, by absorbing the wavelength dependence in the amplification characteristics to compensate. SOLUTION: An isolator 1, a wavelength combining coupler 2, an optical fiber 3, an isolator 4, an optical fiber 5 and a stimulation light source 6 constitute a main part. The optical fiber 5 reveals an absorption property due to the loss of itself and has approximately the reverse characteristic to the amplifying characteristic in stimulating the optical fiber 3, thereby equalizing the gain of the output light having a wavelength dependence over a wide wavelength range. When a stimulating light from the light source 6 is inputted to the optical fiber 3 through the coupler 2, a signal light is inputted to the optical fiber 3 through the isolator 1 and the coupler 2, the signal light is amplified and inputted to the optical fiber 5 through the isolator 4 and the output of the signal light is equalized on the optical fiber 5. |
