The specific scanner disclosed also includes an arrangement for monitoring the profile, position and orientation of the beam spot at {HEAD ~ a plurality} of {TAIL ~ different points} along the scan path 
of
The specific scanner disclosed also includes an arrangement for monitoring the profile , position and orientation of the beam spot at { HEAD ~ a plurality } of { TAIL ~ different points } along the scan path
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH