STOKES PARAMETER CORRECTION METHOD AND STOKES PARAMETER MEASURING APPARATUS

摘要

PROBLEM TO BE SOLVED: To correct errors by calculations to improve the accuracy of measuring a Stokes parameter.;SOLUTION: Electric signals I0, I1, I2, and I3 corresponding to a four-part split component, a 0-degree linearly polarized component, a 45-degree linearly polarized component, and a circularly polarized component respectively obtained from incident light are determined (10 to 34). An equation is suggested for calculating a Stokes parameter with a corrected minimum current error resulting from the fact that the minimum value of the electric signals I1 to I3 is not necessarily zero. An equation is suggested for calculating a Stokes parameter of which the relative angle error between axes defining a Poincare sphere resulting from an error of the absolute angle between a polarizing element and a phase element of an optical system or of the relative angle between the elements is corrected by calculations. Parameters used in these equations are determined by nonlinear least squares fitting (the step 70). By preparing the parameters for the equations by frequency and using different parameters for each frequency, the measuring accuracy can be further improved.;COPYRIGHT: (C)2007,JPO&INPIT