Microchannel plates

For more than forty years researchers have applied the phenomenon of photoemission to convert absorbed incident radiation into an electron stream, which is then amplified by a secondary-emission process. The resulting fast high-gain photon detectors, such as photomultipliers and electron multipliers, are among the fastest and most sensitive devices for recording the collision of a photon (or electron, atom or energetic ion) with a target surface. These detectors have gained wide acceptance in research instrumentation, particularly in mass spectroscopy and scintillation spectroscopy, as well as in optical ranging and optical communication systems. Recently a new—faster, less noisy and more efficient—type of radiation detector has been developed, consisting of a plate traversed by a large number of microscopic channels that serve as electron multipliers.