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