the optic fiber end surface is oriented at an angle of {TAIL ~ 15°} to a normal plane of {HEAD ~ the optic fiber center axis} 
the optic fiber end surface is oriented at an angle of { TAIL ~ 15 ° } to a normal plane of { HEAD ~ the optic fiber center axis }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD