Theelectricfieldforcereceivedbythepaintparticlesisdirectlyproportionaltothevoltageoftheelectrostaticfieldandthechargeamountofthepaintparticles, andinverselyproportionaltothedistancebetweenthespraygunandtheworkpiece.Whenthevoltageishighenough, theareaneartheendofthespraygunformsanairionizationzone.Intenselyionizedandheated, formingadarkredhaloaroundthesharpedgeofthespraygunoraroundthepoleneedle, whichcanbeclearlyseeninthedark.Atthistime, theairproducesastrongcoronadischarge.
