Finite source effect on the polarization degree induced by a single   microlens
  We investigate the effect of a single microlens on Stokes parameters.   Semi-analytical formulae of the microlensed Stokes parameters are derived. The formulae not only reduce the double integrals in the estimations of those quantities but can also be approximated to a useful form in the bypass case. By using our formulation, we show that a combination of polarimetric data with photometric data enables us to estimate not only the finite source effect but also the direction of the microlens motion. 
Hiroshi Yoshida (Fukushima Medical University)