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