{HEAD ~ The optical surfaces} have a high value of elastic modulus, reducing {TAIL ~ coma} and other aberrations associated gravity and acceleration 
reducing
{ HEAD ~ The optical surfaces } have a high value of elastic modulus , reducing { TAIL ~ coma } and other aberrations associated gravity and acceleration
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH