Mapping Focal Branches via Implicit Equations: The Half-Wave Zone Slit Model
Applet Description: Focal Curves in Near-Field Slit Diffraction
This applet derives explicit equations for the focal curves within the Half-Wave Zone Model of slit diffraction.
1. Visualization of Stationary Points
The ap plet identifies the stationary points of the 2D distribution J(x, y) using a distinct color-coded system:
- Red & Blue Points: Represent local maxima and minima, respectively.
- Crosses (Multiple Colors): Represent saddle points positioned between the extrema.
- Symmetry: Note that the distribution of these points is symmetric with respect to the y-axis.
- Curve Cuf1: Corresponds to the real part of the first complex function, f1(z). This branch coincides perfectly with the original implicit function eq00.
- Curve Cuf2, Curve Cuf3 : Correspond to the real part of the complex functions f2(z), f3(z), respectively, and represent subsequent transformations and additional branches of the cubic solution.
Notes: Rendering complex functions is computationally intensive. Please be patient or use a desktop computer for a smoother experience. Below the applet, you will find images of the CAS transformations and the behavior of the curves related to the solutions f1(z), f2(z), and f3(z).
Obtaining the implicit equation (eq00) of the focal curve:

Obtaining the implicit equation of the focal curve (eq0) from the equation (eq00) by eliminating irrationality from it:

1. The transformation to eliminate irrationality in the focal curve introduces additional branches to the implicit function

2. Branches of the complex solutions for the cubic polynomial
