{TAIL ~ A laser unit} 7, wherein said base includes one of a step portion and a cut away portion at a laser light emission end of said base, and wherein {HEAD ~ said photodiode} is disposed at said step or cut away portion 
{ TAIL ~ A laser unit } 7 , wherein said base includes one of a step portion and a cut away portion at a laser light emission end of said base , and wherein { HEAD ~ said photodiode } is disposed at said step or cut away portion
TAIL 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 OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH