For in-vehicle applications, car cameras are the same as mobile phone cameras. They mainly use CMOS instead of CCD as optical sensors. The main reasons are as follows:

The primary characteristic that the sensor used in the active driving assistance system of the car cameras should have is: fast. Especially in high-speed driving situations, the system must be able to record key driving conditions, evaluate this situation and initiate corresponding measures in real time. Essentially, CMOS is a faster image acquisition technology. The unit in the CMOS sensor is usually actively controlled and read out by 3 transistors, which obviously speeds up the image acquisition process. At present, high-performance CMOS-based cameras for car cameras can reach a level of about 5000 frames per second.



The CMOS sensor of the car cameras also has advantages in digital image processing. The CCD sensor usually provides an analog TSC/PAL signal, which may be converted by an additional AD converter, or the CCD sensor must work with a progressive scan method with digital image output.

Regardless of the method, allowing a CCD camera to provide a digital image signal significantly increases the complexity of the system. The CMOS sensor of the car cameras can directly provide LVDS or digital output signals, the various components in the active driving assistance system, and can process these signals directly and without delay. Moreover, in order to achieve this goal, car cameras manufacturers must consider the use of lower cost CMOS sensors. In addition, when strong light is incident, the CMOS sensor will not generate the smear noise that occurs when CCD is used. This will reduce the adjustment time caused by operating errors.