PURPOSE: To make it possible to measure the degree of polarization in real time without a movable part, by measuring the optical intensities of the linearly polarized components of three different angles, and operating the results using specified expression.
CONSTITUTION: Elliptic polarization to be measured is split into three light paths. The optical intensities of the linearly polarized components, which are transmitted through analyzers, are measured by a light detectors. Namely, in the orthogonal coordinates of (x) and (y), an angle formed by the axis, at which the optical intensity of the linearly polarized component of the ellitic polarization to be measured becomes the maximum value, and the (y) axis is made to be . Three angles θ1, θ2 and θ3 formed with the (x) axis are made to satify the relation 0≤θ1<θ2<θ3<π. Thus the optical intensities I1, I2 and I3 of the linearly polarized components are measured. As the sets of the a values of (x) and (y), 1) x=I1cosθ1, y=I1sinθ1, 2) x=I2cosθ2, y= I2sinθ2 and 3) x=I3cosθ3, y=I3sinθ3 are substituted in the Expression I. The maximum value Imax and the minimum value Imin are obtained by operations. The maximum value Imax and the minimum value Imin are substituted in the Expression II, and the polarization degree of the elliptic polarization to be measured is obtained.
ISHIKURA AKIHIKO
MIYAUCHI MITSURU
