{HEAD ~ Another example} of improvement in structure of {TAIL ~ an optical element} is shown in FIG 11 
{ HEAD ~ Another example } of improvement in structure of { TAIL ~ an optical element } is shown in FIG 11
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH