{HEAD ~ Further definition} of {TAIL ~ the produced line} of light, or scan line, is provided by non parallel sides which extend between the reflective surfaces 
of
{ HEAD ~ Further definition } of { TAIL ~ the produced line } of light , or scan line , is provided by non parallel sides which extend between the reflective surfaces
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH