Choosing a
Camera
The camera is the ‘eye’ of a CCTV
system and at its core lies CCD
(charge coupled device) technology.
The CCD is comprised of about 500,000 light sensitive cells called picture elements
(pixels) which convert the light falling onto its surface into an electrical signal. The
performance of the camera, and ultimately the surveillance system, is more
dependent upon the quality of the CCD than any of the other camera components.
Currently, the popular formats are:
■
Half-inch
High performance for high sensitivity and low noise
■
Third-inch
Most popular and ideal for a wide range of applications
■
Quarter-inch
A more recent development
Benefits of CCD Technology
■
Long Life
Produced with a design life of up to 10 years
■
Shock Resistant
Much more rugged than older tube technology
■
Size and Weight
Have enabled the miniaturisation of cameras
■
Spectral Response
Responsive in the near infra red area
Pixels (Picture Elements)
■
Total Pixels
This is the total number of pixels on the CCD faceplate.
They are not all usable
■
Active Pixels
This is the real figure giving the number of pixels
that are actually in use
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For more information contact the Sony Business Information Centre: 01932 816340