| 摘要 |
PURPOSE: To measure spontaneous emission noise in the presence of a signal by speedily turning off a light signal of a specific intensity and measuring the optical output of an optical circuit thereafter. CONSTITUTION: The light signal of an input 12 of an optical amplifier 10 is detected by an optical spectrum analyzer 24. It is represented as a pulsed input light signal 30. The optical spectrum analyzer 24 is set to a zero span at the wavelength of a light signal generator 16, and the intensity of the signal is plotted as a function of time. At a time T0 , the input light signal 30 is switched off by a switch 18. The intensity of an output light signal, right after the input light signal is turned off, represents an ASE noise in the presence of a light signal having the wavelength and intensity of the input light signal 30. Thus, a spontaneous emission noise of an optical circuit in the presence of the signal is measured. |
