Software for Quantification of the NA dependent change of shape in the image formation of a z-polarised fluorescent molecule using vectorial diffraction simulations

The point spread function of a fixed fluorophore with its dipole axis colinear to the optical axis appears donut-shaped when seen through a microscope, but can change to a spot when increasing the tube lens numerical aperture. This phenomenon can be simulated and studied using this Matlab software package, which implements vectorial Jones matrix formalism for the optical setup and the Debye diffraction integral for synthesis of the electric field and intensity distribution in the focal region.