θ
θ
Z axis
Laser Beam
X’
h
q = polar angle
X’ = the pointing distance into the halfraum
h = the focus offset distance
To calculate h, choose a value for X’, Look up q in VisRad and use the following relationship:
h = X’/cos(q)  (assuming we want the focus on the z-axis at the LEH plane)
Key:
Side view of Halfraum
The specification of beam pointing and focusing
R axis
The main variable in this set of calculations is X’.  We want to see how the DANTE and witness plate radiation temperatures and their incident spectra compare to each other as X’ varies every 200 microns from 200 to 800.