In one form {TAIL ~ the detected photoluminescence} is compared to {HEAD ~ detected scattered excitation light} to determine temperature 
In one form { TAIL ~ the detected photoluminescence } is compared to { HEAD ~ detected scattered excitation light } to determine temperature
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH