As the core sensor of car perception, the camera mainly obtains image information and serves various functions of ADAS. Current popular application scenarios of vehicle cameras include: automatic parking, blind spot monitoring BSD, ACC/FCW/LKA, driver monitoring DMS, etc. In addition to the above applications, the electronic rearview mirror is also a point that everyone is very concerned about. Below, the editor will take everyone to understand.

　　The concept of  electronic rear-view mirror has been around for a long time, also known as rear-view mirror camera, which replaces the traditional optical exterior rear-view mirror with a combination of camera + screen. Generally speaking, in order to ensure clear and accurate images, electronic rearview mirrors need to have more complex hardware and software support:

　　In terms of hardware: basic configuration such as high-definition wide-angle camera/multi-camera/lens anti-shake/night vision/fog-breaking function is required.

　　 Software aspect: Need to consider a series of issues such as picture delay/reduction of image distortion/stitching distortion correction/playing frame number/transfer rate, which poses higher challenges to the processing terminal.

　　 But compared with traditional optical exterior rearview mirrors, its advantages are very obvious:

　　 Lower wind resistance/wind noise: Since the external device of the electronic rearview mirror only has a camera, its volume can be reduced to one-third (or even smaller) of the traditional rearview mirror, and the overall design can be more in line with aerodynamics Learn the principle, in addition, high-speed wind noise will also be reduced a lot.

　　 Wider field of view: The curvature, shape and size of traditional optical mirrors are fixed, and the field of view is limited. And electronic rearview mirrors, through the use of different sensors and different angle cameras, we can obtain more images, and even focus on a certain area to observe, to ensure the safety of vehicles and other road participants.

　　 Less affected by the weather: The electronic rearview mirror only needs to have the lens hydrophobic and waterproof function, and the rest is done by the later algorithm and the display in the car. Even in bad weather, the rear picture is still clearly visible.

Reduce the adverse effects of light: First of all, due to the night vision lens, the rear view is still visible in the case of insufficient lighting; in addition, when exposed to strong light (such as the high beam behind the night), it can be eliminated by algorithms. Dazzling.

　　Of course, electronic rearview mirrors are not only advantages, the following problems also need to be further improved.

　　 High cost: The hardware and software structure of the electronic rearview mirror is complex, so the current cost is very high.

　　 Reliability problem: The reliability of the electronic rear-view mirror is definitely not as good as the traditional mechanical structure. On the other hand, the electronic rearview mirror needs to work continuously since the vehicle is started, and the working time is long, coupled with the harsh environment outside the vehicle, the stability of the product is worrying. Once the camera is damaged or the display screen crashes while the vehicle is driving, it will seriously affect driving safety.

　　 Interference problems caused by the shift of sight:

　　 Compared with the traditional optical rearview mirror, the installation position of the existing display screen will have a certain difference. In addition, the focal length of the driver"s observation of the front field of view is not consistent with that of the display screen, which is likely to cause eye fatigue.

　　 On the whole, electronic rearview mirrors still have obvious advantages over traditional optical rearview mirrors. However, due to safety regulations in different regions, apart from concept cars, only a small number of production models in the Japanese or European markets are currently equipped. For example, Lexus ES and Audi E-Tron, which were launched in 2018, also appeared on Mercedes-Benz"s commercial vehicle Actros.

Although the current regulations on electronic rearview mirrors in most regions have not been liberalized, many car companies are actively advancing: In March 2014, an alliance composed of GM, Volkswagen, Toyota and other automakers joined Tesla to promote The National Highway Traffic Safety Administration petitioned for the use of camera-based rear-view and side-view systems. In 2015, Daimler also made a similar proposal. The company hopes to replace traditional rearview mirrors with cameras on heavy trucks.

For China, progress seems to be accelerating: It is understood that the "GB 15084-2013 Performance and Safety Requirements for Motor Vehicle Indirect Visual Field Device" is being expanded. At the same time, the industry standard "Automotive Streaming Media Rearview Mirror" The draft for comments has also been released.