The aspheric surface of {HEAD ~ revolution} is of a design to reduce {TAIL ~ natural aberrations} inherent in imaging using surface of revolutions of the conic family of curves 
The aspheric surface of { HEAD ~ revolution } is of a design to reduce { TAIL ~ natural aberrations } inherent in imaging using surface of revolutions of the conic family of curves
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH