Camera Image Sensor Comparison

An outdoor security camera, like all cameras, uses an image sensor made up of many pixels which registers the amount of light and converts it to the corresponding number of electrons. The brighter the light, the more electrons are generated. There are two main technologies used for the camera’s image sensor.

These two types are the charge-coupled device, or CCD, and the complementary metal-oxide semiconductor, or CMOS. And despite being viewed as rivals in the camera industry, each type of image sensor really has its own strengths and weaknesses. So the better sensor depends on the situation it is to be used in.

CCD sensors were developed specifically for the camera industry while CMOS traces it’s beginnings to standard technology already in use in areas such as memory chips inside PCs. Today, modern CMOS sensors are advancing in technology and the quality is improving immensely.

A CCD sensor offer slightly better light sensitivity and produces a little less noise than CMOS sensors. Better light sensitivity means better image quality in low light conditions.

The two downsides to the CCD sensors are really the true advantages to CMOS sensors. The CCDs make the cameras more expensive since they are harder to put into a camera and an equivalent sensor uses almost one hundred times more power than a CMOS sensor.

With the CMOS sensor, it is very quickly closing the gap in terms of image quality to the CCD sensor. Cameras that are built with CMOS sensors are lower in cost because the cameras are much easier to build.

The CMOS sensor also allows for greater integration possibilities than the CCD sensor which in comparison is designed to be more stringent in terms of function and integration. CMOS sensors have faster readouts which make a big difference in megapixel technology and you will find megapixel cameras with CMOS sensors much more than with CCD sensors simply because of the costs.

In megapixel cameras, the sensors contain over one million pixels, hence the name. To reduce the cost, the sensors are around the same size as VGA sensors meaning the size of each pixel is reduced greatly. This smaller size allows the camera to produce high resolution images with more details but also makes the camera less light sensitive. Since each pixel is smaller in size, and the light reflected from the object is spread across more pixels, it requires better lighting conditions to produce an image.