{HEAD ~ The photoconductor unit} 7, wherein {TAIL ~ the grid electrode} extends in a long side direction that is orthogonal to the short side direction, and the grid electrode has different thicknesses in a thickness direction that is orthogonal to the long side direction and the short side direction 
wherein
{ HEAD ~ The photoconductor unit } 7 , wherein { TAIL ~ the grid electrode } extends in a long side direction that is orthogonal to the short side direction , and the grid electrode has different thicknesses in a thickness direction that is orthogonal to the long side direction and the short side direction
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH