APPARATUS AND METHOD FOR DETECTING POLARIZATION

摘要

An apparatus and method for detecting the state of polarization (SOP). The apparatus of the present invention includes a phase retarder and a polarizer which rotate with different speeds. In the method of the present invention, optical signals passed through the rotating phase retarder and the rotating polarizer are detected and their harmonic components related to rotating frequencies of phase retarder and polarizer are analyzed, which gives the Stokes parameters representing the state of polarization. According to the present invention, the amount of phase retardation at the phase retarder can be obtained together with the state of polarization using frequency component analysis, reducing measurement errors. The present invention has advantages in SOP measurement of wide wavelength range, increasing the measurement accuracy.