  Leakage of diffuse polarized emission into Stokes I caused by the polarized
primary beam of the instrument might mimic the spectral structure of the 21-cm
signal coming from the epoch of reionization (EoR) making their separation
difficult. Therefore, understanding polarimetric performance of the antenna is
crucial for a successful detection of the EoR signal. Here, we have calculated
the accuracy of the nominal model beam of LOFAR in predicting the leakage from
Stokes I to Q, U by comparing them with the corresponding leakage of compact
sources actually observed in the 3C295 field. We have found that the model beam
has errors of less than or equal to 10% on the predicted levels of leakage of
~1% within the field of view, i. e. if the leakage is taken out perfectly using
this model the leakage will reduce to $10^{-3}$ of the Stokes I flux. If
similar levels of accuracy can be obtained in removing leakage from Stokes Q, U
to I, we can say, based on the results of our previous paper, that the removal
of this leakage using this beam model would ensure that the leakage is well
below the expected EoR signal in almost the whole instrumental k-space of the
cylindrical power spectrum. We have also shown here that direction dependent
calibration can remove instrumentally polarized compact sources, given an
unpolarized sky model, very close to the local noise level.
