Phase-modulation method for AWG phase-error measurement in the frequency domain

摘要

We report a phase-modulation method for measuring arrayed waveguide grating (AWG) phase error in the frequency domain. By combining the method with a digital sampling technique that we have already reported, we can measure the phase error within an accuracy of ±0.055 rad for the center 90% waveguides in the array even when no carrier frequencies are generated in the beat signal from the interferometer.