wherein an incidence angle of the image beam to the optical lens is between {HEAD ~ 0 degrees} and {TAIL ~ 90 degrees} 
wherein an incidence angle of the image beam to the optical lens is between { HEAD ~ 0 degrees } and { TAIL ~ 90 degrees }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL