Since its inception in 1914, car rearview mirrors have been with us all the time. Drivers only need to turn their heads to see the side of the car and the field of view behind the car. It is one of the important devices to ensure the safe driving of the car. Right now, as the "ultimate killer" for improving the blind spot of vision, the camera is gradually evolving into a rearview mirror. Could it be said that car rearview mirrors will really be replaced?
What are the shortcomings of traditional rearview mirrors?
One is the big blind spot. Limited by the area of the mirror surface and the adjustment angle, the field of view is not wide; some models that do better in terms of field of view, such as the Subaru Forester and Honda Fit, use the ABC column "slim" and larger rearview mirrors as much as possible Improve the driver"s field of vision. For example, the dual-curvature mirror technology can eliminate blind spots when turning, and the field of view has been doubled; and the anti-glare technology can reduce the impact of the strong light of the rear vehicle on the driver"s line of sight when driving at night. Even if automakers have added a lot of new technologies to the rearview mirrors to continuously improve the blind spots, the shortcomings of the rearview mirrors cannot be ignored. For example, it sometimes obscures a part of the side view; when encountering a car in a narrow section, when reversing into the garage, or even when entering the automatic car washing area, the rearview mirror may be damaged.
The second is that the wind resistance is large. The wind resistance of a car has a professional term called the wind resistance coefficient. In recent years, the wind resistance coefficient of the car has been around 0.3, and the low car can reach about 0.23. The influence of the rearview mirror on the wind resistance coefficient can reach 0.01 to 0.03. In fact, the influence on the wind resistance is very large.
If the rearview mirror is removed, the vehicle can reduce a lot of air resistance. The rearview mirrors installed on both sides of the front window widen the front area of the car. The two seemingly small lenses will actually increase the air resistance by 3% to 6%. Removing the drag they will reduce is equivalent to lowering the roof by half an inch. Because the air resistance of the car is reduced, the drag coefficient helps to reduce fuel consumption, and the wind noise during high-speed driving is also reduced. In order to optimize the body and reduce air resistance, it is more reasonable to abandon the exposed rearview mirrors.
Based on the above two factors, with the help of cameras and LCD screens, the concept of electronic rearview mirrors was born. Skip the "mirror reflection", the road conditions can be directly projected on the display screen by the rear camera to achieve the "rear view effect".
What are the advantages of rearview mirror camera?
1. The wide-angle lens of the camera and various graphics processing technologies plus AR technology can not only eliminate blind spots, but also provide a wider field of view and improve driving safety.
2. The external camera is smaller and more in line with aerodynamics, reducing the drag coefficient, improving fuel economy, and improving vehicle performance.
The future evolution of car rearview mirrors
Since the early 1990s, the camera has been the main product on some concept cars, but the real discussion about the time for the camera to replace the rearview mirror must start in the near future. The reason is still considering the camera"s definition, cost, and reliability. These factors allow the camera to be used in ordinary cars. With the continuous advancement of the times, more and more high-tech equipment appears in the current cars. As the representative country of the global "technical house"-Japan, the camera system and configuration have been used in a mass-produced car . It is estimated that by 2023, 29% of new cars in Japan will be equipped with camera exterior mirrors.
BMW once predicted that camera exterior mirrors will completely replace traditional exterior mirrors in 2019. If this prediction is truly realized, the automotive field will enter a new era. In fact, many concept cars are equipped with external camera rearview mirrors. This new configuration is not only a sense of technology, but also provides a more comprehensive and clear real-time image of the rear while reducing wind resistance, such as the BMW i8 Mirrorless concept car.
The 2016 CT6 launched by Cadillac is equipped with a streaming media camera on the top model, using the high-definition camera at the rear of the car to collect the pedestrian and vehicle conditions behind the car, and display it through the interior rearview mirror. Its visual range is the original Three times the ordinary rearview mirror.
Actually, the idea of abolishing car rearview mirrors has been around for a long time. In 2015, the United Nations "World Vehicle Regulation Harmonization Forum" discussed that if the car meets certain requirements, video alternatives can be considered. However, the recently passed bill in Japan really allows cameras to replace the original car rearview mirrors. This new provision of substantial significance also benefits from the advancement of video technology and the improvement of clarity. However, at this stage, replacing the exterior mirror with a camera will still face some challenges. A sufficiently good camera will increase the cost; the camera exterior mirror is for graphics processing and transmission speed; most countries also have a long way to modify the law.
In China, there is a strange phenomenon in car rearview mirrors. Many car owners have replaced ordinary rearview mirrors with multifunctional smart rearview mirrors! Its "advantage" is mainly that the product has a high degree of integration. The smart rearview mirror integrates the navigation, electronic dog, driving recorder, reversing image and other just-needed functions that the car owner needs. Some also have Bluetooth, online music, WeChat car search, ADAS driving assistance system and other functions. It is a hodgepodge, and it feels very A few years ago, "domestic fake high-end mobile phones" that integrate all the functions of current popular electronic entertainment equipment have many problems in terms of safety and practicability.
Summary: With the continuous innovation of major car companies, ordinary car rearview mirrors will inevitably gradually withdraw from the stage of history. However, as far as the current situation is concerned, even if the concept car is mass-produced, there is still a lot of resistance to completely canceling the traditional rearview mirror. In ordinary family cars, the reduction in wind resistance and fuel consumption of ordinary rearview mirrors is not so obvious, and the replacement of traditional rearview mirrors with electronic equipment will inevitably lead to a significant increase in cost. Therefore, the traditional rearview mirror must continue to exist for a long time. a period of time.