Parameters
wx : half width of the incident beam waist in the XZ plane
wy : half width of the incident beam waist in the YZ plane
lam : wavelength
M2x : M square factor (M2) in the XZ plane
M2y : M square factor (M2) in the YZ plane
z distance from the the curved refracting surface vertex to the waist of the incident beam
R : radius of the curved refracting surface
n0 : refraction index before the surface
n1 : refraction index after the surface
wix : half width of the refracted beam waist in the XZ plan
wiy : half width of the refracted beam waist in the YZ plane
zix : distance from the curved refractive surface vertex to the waist of the refracted beam in the XZ plane
ziy : distance from the curved refractive surface vertex to the waist of the refracted beam in the YZ plane
