FIELD EMITTER ARRAY CATHODE ELECTRON "BULB" FOR ELECTROSTATIC ATOMIZATION AND DISPERSAL

BY COUPLING AN ELECTRON TRANSPARENT THIN FILM WINDOW TO AN ELECTRON GUN IT IS NOW POSSIBLE TO MAKE FREE STANDING ELECTRON SOURCES (BULBS) THAT OPERATE AT MODEST VOLTAGES (<30 KV). THESE SOURCES OF FREE ELECTRONS HAVE BEEN DEMONSTRATED TO BE CAPABLE OF SUSTAINED OPERATION AT ELECTRON BEAM CURRENTS OF ORDER 0.1 MA IN AIR, AND CAN BE USED TO CHARGE INJECT BOTH LIQUIDS AND AEROSSOLS FOR ELECTROSTATIC ATOMIZATION AND DISPERSAL. THE WINDOWS ARE SUFFICENTLY ROBUST TO BE USED FOR DIESEL AND GAS TURBINE NOZZLES AND OTHER DEMANDING ATOMIZER APPLICATIONS. SINCE THE WINDOWS HAVE TO BE KEPT AT OR NEAR GROUND POTENTIAL, THE NEED TO MAINTAIN THE CONVENTIONAL THERMIONIC CATHODE AT ELEVATED POTENTIAL REPRESENTS THE MAJOR IMPEDIMENT RESTRICTING THE APPLICABILITY OF THESE "BULBS". THE USE OF A FIELD EMITTER ARRAY, AS THE GUN CATHODE, NOT ONLY ELIMINATES THE NEED FOR AN ISOLATED HV FILAMENT SUPPLY, BUT PROVIDES INHERENT ROBUSTNESS THAT PERMITS APPLICATION TO THE PHYSICALLY MOST DEMANDING APPLICATIONS. THE PROPOSED PROGRAM WILL DEMONSTRATED THAT FIELD EMITTER ARRAYS CAN BE USED TO PRODUCE COMPACT, RUGGED, AND INEXPENSIVE ELECTRON BULBS THAT WILL BE CAPABLE OF PROVIDING ATOMIZATION AND DISPERSAL OF ALL FLUIDS FROM FUELS AND LIQUID METALS TO AEROSOLS. ANTICIPATED BENEFITS: THE AVAILABILITY OF FIELD EMITTER CATHODE ELECTRON "BULBS" WILL PERMIT THE DEVELOPMENT OF COMPACT, RUGGED, AND INEXPENSIVE ELECTROSTATIC ATOMIZERS, AND THE FULL EXPLOITATION OF CHARGED SPRAYS UNIQUE CHARACTERISTICS. THIS TECHNOLOGY WILL ENABLE DEVELOPMENT OF: POWDER COATING GUNS, LIQUID PAINT SPRAYERS, METAL SPRAYERS, DIRECT POLYMERIZATION COATING GUNS, SPRAY DRIERS, HIGH FLOW RATE ENGINE NOZZLES, OIL BURNER AND AGRICULTURAL SPRAYERS, AND X-RAY SOURCES.