is positioned between second pair of plates 44 46 and outputs negative ions uncharged projectile 13 is output from projectile generator 11 and is propelled through the hole in plate 48 projectile 13 then passes through the hole in plate 48 into region 60 first ion generator 54 outputs positive ions into region 60 which charge projectile 13 to a positive polarity first ion generator 54 thus comprises charging means positioned between second pair of plates 48 50 for positively charging projectile 13 as it passes through first split plate 66 because projectile 13 is positively charged as it passes through the hole in plate 50 into region 94 acceleration occurs in region 94 due to positively charged plate 50 and negatively charged plate 44 as projectile 13 enters region 56 second ion generator 52 outputs negative ions into region 56 which neutralize projectile 13 to a neutral polarity second ion generator 52 thus comprises opposite charging means positioned between first pair of plates 44 46 for neutralizing the polarity of projectile 13 as it passes through second split plate 64 neutrally charged projectile 13 then exits accelerator 220 through the hole in plate 46 fig4 illustrates a second preferred embodiment of a single stage electrostatic projectile accelerator 230 embodying the teachings of the present invention as discussed above in connection with fig3 projectile generator 10 is provided to generate projectile 12 this time charged projectile 12 is here shown for purposes of illustration only as having a positive polarity accelerator 230 further includes plates 44 46 68 an ion generator 52 and a voltage source 62 plate 68 is charged to a positive polarity by.