The authors have recently utilised a birefringent lens for achieving high frequency enhancement. This motivated them to look into the imaging behaviour of such a lens. When a birefringent lens or Biot Lens is placed between two polarisers, the transmittance of this polariser-lens-polariser combination varies radially. The positions of maxima and minima of transmittance of the system can be changed by changing the relative orientation of the transmission axes of the polarisers with respect to the optic axis of the birefringent lens. Consequently, the effective pupil function of the system changes, producing a corresponding change in its point spread function. It has been shown that such a polariser-lens-polariser combination can give apodisation in one extreme and super-resolution in the other.