{HEAD ~ The apparatus} 1, wherein {TAIL ~ said light source unit} has a ring shaped light source 
wherein
{ HEAD ~ The apparatus } 1 , wherein { TAIL ~ said light source unit } has a ring shaped light source
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH