Method of evaluating the optical characteristic of a Mach-Zehnder optical modulator

摘要

PROBLEMS;To provide a method for evaluating characteristics of MZ interferometers in an optical modulator having a plurality of MZ interferometers.;MEANS FOR SOLVING PROBLEMS;When an optical modulator (1) includes a plurality of MZ interferometers (2,3), the output light contains a signal component at the modulation frequency and sideband components at higher orders. It is impossible to accurately evaluate the characteristic of the MZ interferometers on the basis of the component at the modulation frequency (zero-order). The present invention does not use the zero-order component normally having the highest intensity. That is, the characteristic of the MZ interferometers are evaluated by using a side band intensity of the component other than the zero-order component.