One method for producing the halftone screen is now explained in {HEAD ~ formal terms} for {TAIL ~ the gradation correction} using a non periodic screen function 
for
One method for producing the halftone screen is now explained in { HEAD ~ formal terms } for { TAIL ~ the gradation correction } using a non periodic screen function
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH