ABSTRACT
In both the eye (see Section 4.2.1) and a camera, the light coming
from a source is focused with a lens onto a detection plane. In
the former case, the detection plane is the retina where cells,
which are sensitive to changes in light intensity, encode the image
and send it to the brain, while in the latter case, the detection
plane contains either a photographic film (see Section 1.4.2) or an
electronic detector, inwhich light intensity is converted to an electric
signal. In the electronic camera, the photodetectors are required to
detect light, which put out an electrical signal whose amplitude is
proportional to the photons striking the surface. Such cameras can
be either analog or digital. In the former case, the detectors coupled
acquisition and display together and provide higher resolution but
with limited dynamic range and fixed detector contrast, while in
the latter case, the detectors have separated acquisition and display
system providing higher dynamic range and noise-limited contrast
but with lower resolution.
