Electrophysics AstroScope 9350, Operating Manual

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1.4 How Image Intensifiers Work
Image intensifiers are predominant in night vision applications due
to their ability to amplify low-light scenes at night, making them
visible to the human eye and commercial cameras and camcorders.
Unlike thermal images, image intensifiers can be used to read
vehicle license tags and registration markings on boats and aircraft,
as well as to recognize faces, which can be entered as evidence in
criminal prosecutions.
The sequence to image formation in an image intensifier is as
follows: light is converted to electrons then converted back to light,
making intensifiers very simple devices featuring very high
resolution and extremely low power consumption.
Photons Electrons Photons
Photo
Cathode
Microchannel
Plate
NVD Image
Phosphor
Screen
Unenhanced
Image
A night vision system based on an image intensifier operates as
follows:
1. The very dim light reflected by scenes at night (lower than 0.1
lux) is focused by an objective lens onto a highly sensitive
1-5