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CCD (Charge-Coupled Devices) Image Sensors
Currently the one of commonly used image sensor, CCDs capture light onto an array of light-sensitive diodes, each diode representing one pixel. For colour images, each pixel is coated with a film of red, green, or blue (or complementary colour scheme) so that each particular pixel captures that one particular colour.
The pixel, made up of a light sensitive diode, converts the light photon into a charge, and the value of that charge is moved to a single location in a manner similar to a row of people passing buckets of water. At the end, the charge is amplified. Since this "bucket brigade" is accomplished by applying different voltages to the pixels in a succession, the process is called charge-coupling. Because the value in the pixel is moved by applying different voltages, CCD sensors must be supported by several external voltage generators. In addition, CCDs require a specialized manufacturing process that cannot be used by any other device.
Applications
In digital cameras which is use for high quality use CCD sensors.
CCD Sensors widely use in medical science. It is use high-quality image sensors for various
types of digital dental x-ray imaging: intra-oral, panoramic, cephalometric, general X-ray
imaging and non-destructive inspection.
CCDs remain important in electronics inspection primarily.
Advantages
CCD sensors have better light sensitivity and less noise.
CCDs have of their superior read noise performance, in addition to their wide dynamic range.
CCDs include high signal-to-noise ratio, and high shutter-rejection ratio.
CCD sensors create high-quality and low-noise images.
Disadvantages
CCD sensors are that they are analog components that require more electronic circuitry
outside the sensor, they are more expensive to produce, and can consume up to 100 times
more power than CMOS sensors.
The increased power consumption can lead to heat issues in the camera, which not only
impacts image quality negatively, but also increases the cost and environmental impact of the
product.
CCD sensors also require a higher data rate, since everything has to go through just one
output amplifier, or a few output amplifiers.
CCD sensors are expensive and harder to manufacture than CMOS chips.
Digital cameras that use CCD chips are usually weight than to their CMOS counterparts.
CCD sensor traditionally consumes more power whereas CMOS sensor uses less power to operate.
