IDL in Numerical Simulation of X-Ray Components

The IDL program "pwg_gui", developed at the Department of X-Ray Physics at the University of Göttingen, caculates the electric field inside a planar x-ray waveguide. This is done by numerically solving the so called parabolic wave equation. The algorithm used consists mainly of solving a tridiagonal matrix equation that is done using the LAPACK routines provided by IDL.

The screenshots show the graphical user interface of the program. On the left hand side, geometrical paramaters of the waveguide like its thickness or length as well as some calculation and display parameters can be entered and the simulation can be started by clicking on the "calculate current field" button.

On the right hand side of the first screenshot you can see the electric field intensity inside the x-ray waveguide. The waveguide is hit by an incident plane wave coming from the left. Far away from the entrance non-zero intensitity is only seen inside the guiding layer.

The second screenshot gives a graphical representation of the eigenvalue equation for the eigen modes of the waveguide. The intersections of the white and the yellow curves are calculated numerically.