An image sensor or imaging sensor is a sensor that detects and conveys the information that constitutes an image. It does so by converting the variable attenuation of waves into signals. The waves can be light or other electromagnetic radiation. Image sensors are used in electronic imaging devices of both analog and digital types. As technology changes, digital imaging tends to replace analog imaging.
Early analog sensors for visible light were video camera tubes; currently used types are semiconductor charge-coupled devices (CCD) or active pixel sensors in complementary metal–oxide–semiconductor (CMOS) or N-type metal-oxide-semiconductor (NMOS) technologies.
The first digital cameras used CCD (Charged Coupling Devices) to turn images from analog light signals into digital
pixels. They’re made through a special manufacturing process that allows the conversion to take place in the chip without
distortion. This creates high quality sensors that produce excellent images. But, because they require special
manufacturing, they are more expensive than their newer CMOS counter parts.
CMOS (Complimentary Metal Oxide Semiconductor) chips use transistors at each pixel to move the charge through traditional wires. This offers flexibility because each pixel is treated individually. Traditional manufacturing processes are used to make CMOS. It’s the same as creating microchips. Because they’re easier to produce, CMOS sensors are cheaper than CCD sensors.
Because CMOS technology came after CCD sensors and are cheaper to manufacture, CMOS sensors are the reason that digital cameras have dropped in price.
The Difference / Advantage
- CCD sensors create high-quality, low-noise images. CMOS sensors, traditionally, are more susceptible to noise.
- CMOS traditionally consumes little power. Implementing a sensor in CMOS yields a low-power sensor.
- CCD sensors have been mass produced for a longer period of time, so they are more mature. They tend to have higher quality and more pixels.
- CMOS allowing users to shoot 1080p video and apply complex imaging effects with ease.
- CCD sensors have been thought to produce better-looking images with less visual noise and distortion.
- CMOS sensors scan what is in front of the lens, Beyond Image Quality, Speed, Autofocus and Video, Low-Light Shooting.
- CMOS sensors are already superior to CCD sensors in terms of power consumption. You get a much longer battery life out of a CMOS camera, which means you can take more pictures.