An electrode to be used for an electrostatic lens, wherein the electrode at least includes: a first substrate having a first through-hole and a second substrate having a second through-hole; the first substrate having a thickness smaller than the second substrate; the first through-hole having a diameter smaller than the second through-hole; the second substrate having a specific resistance smaller than the first substrate, wherein the first substrate and the second substrate are superimposed so that the first through-hole and the second through-hole are aligned relative to each other. Notching taking place near any of the through-holes in a dry etching process can be reduced, and thus, the through-holes can be formed accurately.