{HEAD ~ A thickness} of the same substrate may determine {TAIL ~ a numerical aperture} of the optical element 
determine
{ HEAD ~ A thickness } of the same substrate may determine { TAIL ~ a numerical aperture } of the optical element
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH