The sensors used in DSLR nowadays are made from either CCD (charge
coupled device) or CMOS (complementary metal oxide semiconductor). Both
function as converting light into electrons.
CCD is a device specially made to convert the light to electron, it
works with the same theory as the solar panel used. The light hits on
the surface of the pixel and each will convert from analog to digital
CMOS on the other hand consists of several transistors on each pixel,
the same transistor that used for making microprocessors.
The question on whether CMOS sensor is better or CCD sensor has been
going for years with no convincing answer yet. CCD has been in produced
in our world for years and the technology has been mature and tends to
perform better in terms of noise and quality. CMOS has smaller surface
hit by the light as it consists of several transistor and part of the
photons hitting the transistor instead of the photodiode. However CMOS
technology is picking up very fast due to its flexibility usage in
different manufacturing. And CMOS is also easier to fabricate and is a
lot cheaper than CCD. Other than this, CMOS consume a lot less power
compare to CCD. Consuming less power not only saves in batteries life,
it also produces less noise. CCD consumes a lot more power and it tends
to get hot faster, when photodiode get hot, the noise also goes up.
An example of camera sensor
In summary, CCD sensor has the better quality and a much mature
technology. It is used in high end camera to create the images with
great quality and sensitivity. CMOS on the other hand is cheaper and
consume low power, the technology of CMOS is ever improving and is
currently said to be on par with the quality of CCD sensor and it is
still improving. So everyone is expecting CMOS technology in photography
quality to overtake CCD soon. And currently CMOS sensor is used in most
of the highest end camera.
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