{HEAD ~ A light beam output unit} 212 combines two circularly polarized light beams having {TAIL ~ opposite handedness} to each other to produce a composite light beam CB 
{ HEAD ~ A light beam output unit } 212 combines two circularly polarized light beams having { TAIL ~ opposite handedness } to each other to produce a composite light beam CB
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH