luminescent target means , for converting to luminescence values {HEAD ~ the photoelectron emission} from {TAIL ~ test points}  
from
luminescent target means , for converting to luminescence values { HEAD ~ the photoelectron emission } from { TAIL ~ test points }
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH