Is there something wrong with my MATLAB code for calculating the point spread function?

I have the two following PSFs for the same image; the first has a detector pitch of 0.2mm and the other of 0.015mm.

I'm curious as to whether or not this is a problem with my code (because I have spent days debugging to no avail), or is this the expected outcome of a smaller detector pitch? If so, I will keep on debugging, but I want to be sure there's a light at the end of the tunnel if so.

[DGM]

We don't know what your inputs were or what your code was, so it's hard to say. It's not a subject with which I'm familiar enough to confidently intuit, but I'm sure others who are more familiar would appreciate the clarification.