comparing the types of the necessary optical parts with {HEAD ~ the types} of {TAIL ~ the installed optical parts} which have been identified by the sensors to recognize at least one mismatched optical part; and 
of
comparing the types of the necessary optical parts with { HEAD ~ the types } of { TAIL ~ the installed optical parts } which have been identified by the sensors to recognize at least one mismatched optical part ; and
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH