The method 1 further including {TAIL ~ the step} of providing a protective, light transmitting coating on {HEAD ~ the external surface} of said defined envelope 
The method 1 further including { TAIL ~ the step } of providing a protective , light transmitting coating on { HEAD ~ the external surface } of said defined envelope
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH