ANALOG OPTICAL TRANSMITTER AND OPTICAL FIBER AMPLIFIER

摘要

PURPOSE:To improve S/N characteristics by using a semiconductor laser element which emits a signal light intensity-modulated by an additional signal of a frequency lower than that representing a spectral beam width of an output laser light in addition to an analog electric signal of a RF band to an optical fiber as a signal light source. CONSTITUTION:An analog optical transmitter comprises a signal semiconductor laser element 3 for emitting a signal light intensity-modulated by an analog electric signal 21 of an RF band, an optical fiber 4 for transmitting the signal light emitted from the element 3, and a photodetector 5 for converting the signal light transmitted through the fiber 4 into an electric signal. The element 3 has a configuration for emitting a signal light further intensity-modulated by an additional signal 22 of a frequency lower than that representing a spectral beam width of the element 3 to the fiber 4. Thus, interaction noise generated by multiple reflections is reduced, and S/N characteristics are improved.