For example, the infrared light source 92 may be physically separated from the light source 74 by superimposing {HEAD ~ the locator beam} 90 onto the light from the light source 74 with a beam splitter and {TAIL ~ steering optics} 
with
For example , the infrared light source 92 may be physically separated from the light source 74 by superimposing { HEAD ~ the locator beam } 90 onto the light from the light source 74 with a beam splitter and { TAIL ~ steering optics }
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 HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL