What is a CCD ?
Charge Coupled Devices (CCDs) were invented in the 1970s
and originally found application as
memory devices. Their light sensitive properties were
quickly exploited for imaging applications
and they produced a major revolution in Astronomy. They
improved the light gathering power of
telescopes by almost two orders of magnitude. Nowadays
an amateur astronomer with a CCD
camera
and a 15 cm
telescope can collect as much light as an astronomer of the 1960s equipped
with a
photographic plate and a 1m telescope.
CCDs work by converting light into a pattern of
electronic charge in a silicon chip. This pattern of
charge is
converted into a video waveform, digitised and stored as an image file on a
computer.