The base is preferably formed such that the registration surface 22 is in a precise location with respect to the optical system so that {HEAD ~ the active surface} 16 of {TAIL ~ the substrate} is at a focal point within a few microns 
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The base is preferably formed such that the registration surface 22 is in a precise location with respect to the optical system so that { HEAD ~ the active surface } 16 of { TAIL ~ the substrate } is at a focal point within a few microns
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH