| Subject |
has definition |
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| image intensifier | An electronic device for increasing the brightness of a faint optical image. The image is first formed on a thin metallic surface called a photocathode from which electrons are then ejected. The stream of electrons is accelerated and focussed onto a phosphorescent screen which glows brightly as a result of the impact. |
| integrating detector | Any imaging device, like a photographic emulsion or CCD, which can build up more signal and contrast by a longer exposure to light or other electromagnetic energy. |
| microchannel plate | A compact electrostatic high-voltage electron multiplier with a very large number of narrow pores or channels. A photoelectron generated at the entrance face (photocathode) stimulates a cascade of secondary electrons down the nearest channel to produce a huge cloud of charge at the output face. The output pulse can be used in many different ways to record the event. If it impacts a phosphor screen then light emission can be detected with a CCD. Direct electrical detection can be obtained using a Multi Anode Microchannel Analyzer. |
| PAPA | Precision Analogue Photon Address. |
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