A computer controlled wireless focus mechanism is used to regulate {TAIL ~ the vertical distance} between the focused laser assembly and {HEAD ~ the work surface} 
A computer controlled wireless focus mechanism is used to regulate { TAIL ~ the vertical distance } between the focused laser assembly and { HEAD ~ the work surface }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD