Patent ID: 8446591
Filing Date: 2013-05-21
Classification: G01B,G01M,G02F

Abstract:
1. A method for evaluating characteristics of an optical modulator including a first Mach-Zehnder, MZ, interferometer, wherein the MZ interferometer includes a branching section, two arms, a coupling section, and electrodes, wherein the method comprises a step of applying driving signal, a step of adjusting bias voltage, a step of measuring output intensity and a step of evaluating characteristics, wherein the step of applying driving signal is a step of applying driving signal to an MZ interferometer, wherein the step of adjusting bias voltage is a step of setting phase difference between the bias voltages to be applied to two arms of the MZ interferometer to it or a step of setting the phase difference between the bias voltages to be applied to the two arms of the MZ interferometer to 0, wherein the step of measuring output intensity is a step of measuring the output intensity from the MZ interferometer whose bias voltage is adjusted at the step of adjusting a bias voltage, and wherein the step of evaluating characteristics is a step of evaluating characteristics of the MZ interferometer using intensity of the sideband component of the second-order component in the output from the MZ interferometer measured at the step of measuring the output intensity.