In other words, I wanted to know if there is a limit for this "loss of directionality" information Scott correctly mentioned when you have angles hitting the pinhole, with the fiber tip very close to it. And how it affects (if it does) the observed diffraction pattern.
Thanks Scott.
Yes, but the spatial filter analogy would hold for the case in which I put a lens to focus the beam at the pinhole position, right?
In my case I am really interested in the effect on diffraction of the deltaZ change for the diverging wave scenario. Not the overall energy...
Case (a) is the textbook of a planar incident wavefront and below it in the figure is the known simple formula for the central spot and fringes, or minima and maxima, angular distribution with respect to the optical axis.
So, the question here is regarding case (b). The position (usually...