The apparatus 1, wherein said second and third reflectors {HEAD ~ each} respectively describe in {TAIL ~ cross section}, segments of parabolas intersecting one another, each of said segments of parabolas lying along a generally arced line 
respectively describe in
The apparatus 1 , wherein said second and third reflectors { HEAD ~ each } respectively describe in { TAIL ~ cross section } , segments of parabolas intersecting one another , each of said segments of parabolas lying along a generally arced line
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL REL 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 OTH