The alignment of lens 1 and 2 is as follows:


The probe was aligned to minimize the offset of the probe from the center of the four circular irised end plates.
If will name the circular end plates 1 through 4, with 1 & 2 belonging to Lens 1 and 1 being the upstream end and
3 & 4 belonging to Lens 2 and 3 being the upstream end.  The offset of the center of the 4 circular endplates from the probe are given in mils:


                {Lens 1}               {Lens 2}           

Endplate #    1             2        3              4 

X offset =     0		     0       -5             +1       mils

---------->  Beam travel

Y offset =    +6            -6       -5             +5       mils


Z = 0 is the outside upstream edge of the Lens 1 (cathode) endplate.  (Not the edge of cathode attachment)

The length of Lens 1 (without gun piece) = 0.1758 m (Gun piece adds 0.00127 m)   Lens 1 Center = 0.08777 m
The length of Lens 2 = 0.1759 m,  Lens 2 Center = 0.3136 m

The space between the lens = 0.0492 m.