{TAIL ~ a first focusing reflector} which directs {HEAD ~ source} provided radiation to the sample in the transmission mode 
{ TAIL ~ a first focusing reflector } which directs { HEAD ~ source } provided radiation to the sample in the transmission mode
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH