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physical object > artifact > device > instrument > optical device > detector > imager

imager
subject			fact

imager	is a kind of detector
instrument	has operator
artifact	has creator
	has creation date
	has purpose
	has owner
physical object	has location or center of gravity
	has angular momentum
	has mass
	has velocity
	has momentum
	has temperature
	has volume
	has extent
	has material

Kinds of imager :

• image intensifier (1 kind, 5 facts) - 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 (15 kinds, 38 facts) - 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 (1 kind, 4 facts) - 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 (2 facts) - Precision Analogue Photon Address.