| 摘要 |
PROBLEM TO BE SOLVED: To provide a gain equalizer which can equalize respective polarized waves in transmission loss wavelength dependency when the gain of the light amplified by a polarization plane holding optical amplifier is equalized. SOLUTION: A 1st gain equalizer 2 and a 2nd gain equalizer 3 are cascaded. The light signal amplified by the polarization plane holding optical amplifier has insertion loss of only X polarization by the 1st gain equalizer 2 in an in-use wavelength band. The 2nd gain equalizer, on the other hand, gives insertion loss of only Y polarization. Consequently, the respective polarized waves are equalized in transmission loss wavelength dependency. |
