{HEAD ~ The non spherical annular area} has a progressive reduction from maximum addition to zero addition, which enables vision from reading to {TAIL ~ intermediate and distance vision} 
{ HEAD ~ The non spherical annular area } has a progressive reduction from maximum addition to zero addition , which enables vision from reading to { TAIL ~ intermediate and distance vision }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL