The improvement 1, wherein said adjusting means further comprises a light shielding member restricting {HEAD ~ the amount} of {TAIL ~ light} leaving said main reflecting means 
The improvement 1 , wherein said adjusting means further comprises a light shielding member restricting { HEAD ~ the amount } of { TAIL ~ light } leaving said main reflecting means
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH