WAVELENGTH STABILIZED MODULE, STABLE WAVELENGTH LASER BEAM GENERATING DEVICE AND OPTICAL COMMUNICATION SYSTEM

摘要

A wavelength stabilized module and a stable wavelength laser beam generating device which are minimized in reflection light returning to a light source from an FBG. The wavelength stabilized module comprises an optical branching filter (122) for branching a laser beam, led from a light source (110) via a fiber (143), into first and second beams, an FBG (210) for transmitting a beam of a specified wavelength included in the branched first beam and reflecting a beam of the other wavelengths, and a light quantity change operation unit (311) for detecting a change in quantity of light transmitted the FBG by using the second light beam as a reference beam, the module being so constructed as to guide a beam reflected off the FBG (210) to the outside and to feed back the detected change in light quantity to the light source (110).