CMOS Security Camera

When researching security cameras for your home or business, you may come across two different types of image sensors used to produce the digital images when recording: CCD and CMOS. CCD and CMOS security cameras utilise different technology and therefore each have their own distinct pros and cons.

What are Image Sensors?

An image sensor is located just after the lens of a camera. The light that passes through the lens lands on the sensor; the sensor then collects the light and converts it into voltage electrons. This is commonly known as image pixels, which are then converted into a digital signal using a convertor. CMOS and CCD are two separate types of image sensor used in this process.


What distinguishes CMOS from CCD is that CMOS sensors have circuitry at the pixel level. Therefore every pixel on the sensor is read and transmitted at the same time. Additional technology is used to reduce noise and other factors, helping convert the voltage into digital data. CMOS doesn’t require a separate image processor outside the pixel array because of this, which makes them quicker in converting visual information than CCDs.

Whilst this is a positive, the extra technology that is required on the sensor crowds the pixels, which in turn limits their ability to capture light and this results in a poorer image clarity than CCDs.

CCD sensor pixels are specially designed to capture light only. This results in higher-quality images, but the camera runs less efficiently as a result. By CMOS sensors adding technology to the pixels, it processes the captured information faster and makes the sensor very efficient at the cost of more noise in the final image.

Some of the Benefits of a CMOS Camera:

As you can see, there are distinct strengths and weaknesses to both CMOS and CCD security cameras. But opting for a CMOS sensor will provide you with the following:

  • The sensors are able to convert information quicker than CCDs and this results in less power consumption. The difference in consumption can be a large factor.
  • The inclusion of amplifiers and convertors within the chip means the cost of production is lower and the cameras cost less.
  • There is no need to invest in separate circuitry outside of the sensor, saving both time and money.

CMOS technology has improved a lot since the 1990s, and the old days of fuzzy CMOS images are gone. The clarity of CMOS sensors has improved, as well as resolution – there are CMOS that can reach AHD (Analog High Definition) of 720p or 1080p. Nowadays most security camera models are CMOS cameras. In fact, cameras today are not usually labelled as CCD/CMOS anymore.