{HEAD ~ a photoelectric conversion element} that converts {TAIL ~ an optical signal} into an electrical signal and that accumulates signal electric charge, 
converts
{ HEAD ~ a photoelectric conversion element } that converts { TAIL ~ an optical signal } into an electrical signal and that accumulates signal electric charge ,
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH