Camera Sensors

The camera's image sensor is the chip responsible for converting light into electrical signals. There are two main types of sensors: charged coupled device (CCD) and complementary metal oxide semiconductor (CMOS).

 

CCD Sensor

CCD technology has been used in cameras for decades. They are more sensitive to light than CMOS sensors and produce better images in low light conditions. Because these chips are specially designed for cameras, they are more complex and are more expensive.

 

CMOS Sensor

CMOS technology is based on standard technology used in memory chips found inside electronic devices such as PCs. These chips are multi-purpose and allow all camera logic to be contained in them. The are cheaper than their CCD counterparts but are less sensitive to light. Still recent advances in CMOS technology bring them closer to their CCD counterparts. A testimony to this is their increased use in both VGA and megapixel IP cameras.

 

Sensor Size

The size of the sensor is usually 1/2" 1/3" or 1/4". As a rule of thumb, the larger the sensor, the higher the quality of image produced and the higher the price. Quality 1/3" and 1/4" sensors can produce images that are comparable to those produce by 1/2" sensors.

 

Sony VS Sharp

Some argue that the higher price tag for cameras with a Sony sensor is justified because a Sony sensor produces better quality images than a Sharp sensor. However when comparing similar sized sensors, 1/3" CCD for example, using a side by side benchmark test it was found that there is little if no practical difference between the images they produce.

 

References

"Image sensors: CCD vs. CMOS." Axis Communications. Axis Communications, n.d. Web. 23 Sep 2010.

"Technical Support." Ones and Zeros Ireland Digital Electronics. Ones and Zeros Ireland Digital Electronics, n.d. Web. 23 Sep 2010.