An aerodynamic nozzle for aerosol particle beam formation into a vacuum comprises a tubular column having a first stage section with a plurality of spaced aerodynamic lenses therein so that an aerosol entering the inlet end of the first stage section is formed into a beam of generally aligned particles. The beam exits the first stage section through an outlet orifice into a second stage section also having a plurality of spaced aerodynamic lenses to maintain the aerosol in its beam form. The beam then exists through a nozzle to an orifice at the discharge end of the second stage section into an evacuated region. The pressure decreases from the first stage (which is preferably at atmospheric pressure) to the second stage to the evacuated region.