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