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