LOW-COST HIGH-CURRENT IMAGING ELECTRON MULTIPLIER DEVICE

CONVENTIONAL MICROCHANNEL PLATES (MCPS) ARE TOO NOISY FOR EXTREMELY LOW PHOTON-COUNTING DETECTOR APPLICATIONS AND THEIR LOW OUTPUT CURRENT DENSITIES LIMIT THE FRAMING SPEEDS OF MCP-BASED SIGNAL PROCESSING DEVICES SUCH AS THE MICROCHANNEL SPATIAL LIGHT MODULATOR. PHOTOMULTIPLIER TUBES, HOWEVER, HAVE EXCELLENT NOISE CHARACTERISTICS BUT NO IMAGING CAPABILITY. WE PROPOSE AN IMAGING ELECTRON MULTIPLIER (IEM) DEVICE THAT SIMULTANEOUSLY OFFERS THE LOW-NOISE GAIN OF PHOTOMULTIPLIER TUBES AND THE IMAGING PROPERTIES OF CONVENTIONAL MCPS AT HIGH OUTPUT CURRENT DENSITIES. THE PROPOSED IMAGING ELECTRON MULTIPLIER (IEM) DEVICE INCORPORATES AN AXIALLY ALIGNED STACK OF DISCRETE HIGH-RESOLUTION, POROUS DYNODES EMPLOYING A HIGHLY-CONDUCTIVE SECONDARY-ELECTRON-EMITTING MATERIAL. ITS MODULAR DESIGN PERMITS THE USER TO TAILOR THE DEVICE FOR SPECIFIC APPLICATIONS: E.G., IN A LARGE-AREA MCP PHOTOMULTIPLIER TUBE, THE IEM IS EXPECTED TO OFFER SIGNIFICANTLY IMPROVED SIGNAL-TO-NOISE RATIO OVER A CONVENTIONAL MCP. THE IEM IS ALSO CAPABLE OF VERY HIGH CURRENT OUTPUT WHEN COMPRISING A LARGE NUMBER OF DYNODE STACKS ( 10), FUNCTIONING AS A POWER MICROCHANNEL PLATE. THE IEM SHOULD FIND APPLICATIONS IN ASTRONOMICAL IMAGING, SPECTROSCOPY, NIGHT VISION IMAGING, AND IN MCP-BASED HIGH-SPEED SPATIAL LIGHT MODULATORS.