Optical amplifying apparatus

摘要

A plurality of pumping light sources (1) which generate pumping light having wavelengths different from each other are connected to respective input ports of an optical multiplexer via optical reflectors (3). The respective pumping light is stabilized by optical reflectors with respect to the oscillating wavelengths, and is multiplexed by an optical multiplexer (4). The multiplexed pumping light is multiplexed to signal light passing through an optical fiber (6) for amplification. In the respective optical reflectors (3) and optical multiplexer (4), the optical lines are formed of materials whose differential coefficients of changes in the center wavelengths with respect to changes in temperature in the usage wavelength band are almost the same, and the set wavelengths of the respective input ports of the optical multiplexer (4) are made almost coincident with the center wavelengths of the input side optical reflectors (3), wherein the respective optical reflectors (3) and optical multiplexer (4) are disposed in almost the same environmental temperature atmosphere. Therefore, it is possible to always make coincident the center wavelength of the optical reflectors and that of the input ports of an optical ports of an optical multiplexer corresponding thereto regardless of changes in temperature without compensating for the temperature.