| 摘要 |
Provided are an optical amplifier, for amplifying a light signal; first and second light dividers, optically connected to an output terminal of the optical amplifier; and first and second light receivers, for receiving light divided by these light dividers. A variable wavelength filter is located between the first optical coupler and the second optical couler. In addition, provided are a filter driver, for sweeping a center wavelength that passes through the variable wavelength filter; a counter circuit, for counting output peaks of the second light receiver; and an output controller, for controlling an output of the optical amplifier so as to maintain a constant output by the first light receiver. The output controller employs a voltage output by the count circuit as a reference voltage for controlling changes in the light output power of the optical amplifier that are in consonance with the value held by the counter, i.e., in consonance with the number of signal light wavelengths. When the number of multiplexed wavelengths is changed, a constant output level for one wavelength can be maintained. |
