Why does the car camera choose CMOS technology?
richmor
richmor.net
2018-04-25 10:58:44
First of all, the primary characteristics of sensors used in active driving assistance systems are speed. Especially in high-speed driving situations, the system must be able to record critical driving conditions, assess such conditions and initiate relevant measures in real time. In essence, CMOS is a faster image acquisition technology—the cells in a CMOS sensor are usually actively controlled and read by three transistors, which significantly accelerates the image acquisition process. Currently, high-performance CMOS-based cameras can reach a level of about 5,000 frames per second.
Second, CMOS sensors also have the advantage of digital image processing. CCD sensors usually provide analog TSC/PAL signals, which may have to be converted using an additional AD converter, or the CCD sensor works with a progressive scan method with digital image output. Either way, the use of CCD cameras to provide digital image signals significantly increases system complexity; CMOS sensors can directly provide LVDS or digital output signals, and components in active driving assistance systems can be directly and without delays. Deal with these signals.
Moreover, in order to achieve this goal, vehicle camera manufacturers must consider using lower-cost CMOS sensors. In addition, the CMOS sensor does not generate Smear noise that occurs when using a CCD when there is a strong light incident. This will reduce the adjustment time caused by operational errors.
What are the characteristics of the car camera module?
In addition to using COMS technology for automotive applications, automotive camera modules also have other requirements in terms of process and packaging. Compared with the mobile phone camera, the car camera technology is more difficult, mainly due to its high-reliability requirements. Unlike general cameras, automotive cameras have a long working time, and their environment is often agitated. Once they fail, they will pose a fatal threat to user's life safety. Therefore, the requirements for modules and packages are strict. Car camera tests need to be immersed in water for several days, and temperature tests over 1000 hours, including rapid jumps from minus 40 degrees to minus 80 degrees. And the car camera needs to have night vision to ensure normal use at night.