FIGS 16, 17A, and 17B illustrate {HEAD ~ a grid electrode} 124B according to {TAIL ~ a second exemplary embodiment} 
according to
FIGS 16 , 17A , and 17B illustrate { HEAD ~ a grid electrode } 124B according to { TAIL ~ a second exemplary embodiment }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL