CCD-Camera
A camera that uses a charge-coupled device (CCD) to gather light of
the object being photographed and to transfer this information into
a computer in a digital format.
CCD: An electronic imaging device widely used in astronomical
applications and, nowadays, in consumer digital cameras. The CCD
consists of semiconducting silicon; when photons
of light fall on it, free electrons are released. To preserve the pattern
of light falling on the CCD, the photons are collected in a matrix of small
picture array of electrodes, called gates, formed on the surface of the CCD.
The electric charge in each pixel is then transferred to the ends of the
rows by systematically changing the voltages on each gate so that the charge
passes along as if on a conveyor belt. Finally, the electrons in each
little packet of charge from individual pixels are counted and converted
into a form in which the whole image can be stored in a computer or
displayed on a television screen. (Mitton, 1993, Dictionary of Astronomy,
London: Penguin Books)