Originally developed to enhance night vision in military applications, image intensifiers combined with improved CCD imaging sensors emerged as serious contenders for low-light scientific imaging applications in the early 1990s. Today many intensified CCD cameras employ the same CCD sensor found in cooled scientific cameras, the goal being to combine a high-gain amplifier with a good low-light image sensor.
A typical intensifier has three key elements. The first stage is a flat, circular photocathode formed from various semiconductor materials within which photon energy is converted to electrons. Electrons emitted from its rear surface travel tens of microns across an electric field to a two-dimensional microchannel plate, which, by virtue of a high-voltage differential acting across it, can dramatically amplify the number of electrons passing through it (gain multiplications of 10,000 to 80,000 are typical). These then impinge on a phosphorescent output screen on one side of a fiber optic faceplate, forming an amplified image that can be visualized on the faceplate. With standard night-vision goggles, that is the extent of the intensifier components..

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