If you are still stubbornly thinking that the rearview mirror of the car is the driver’s "second eye", just an ordinary mirror used to expand the driver’s field of vision, then I can only tell you with great regret that you are again" Two". If you think about it, now that science and technology are developing so rapidly and the automobile industry is developing so fast, will the rearview mirrors of that year still be as simple as before? Of course not. With the introduction of more and more new technologies, the technological content of car rearview mirrors is also getting higher and higher, the functions are also increasing, and the effects are becoming more and more powerful.
So, having said so much, what science and technology are included in modern car rearview mirrors? And what kind of convenience does these technologies bring to our driving life?
Since it is a rear-view mirror, the basic skills of expanding the field of vision must be solid and powerful. By changing the shape of the rearview mirror and increasing the area to expand the field of view, the effect of doing so is after all limited. In addition to the "rabbit ear mirrors" used in large cars, this method has no effect on other models. No one wants to look at their own car with two huge "rabbit ears" drooping. Therefore, how to expand the field of view without affecting the drag coefficient of the vehicle has to work on the mirror surface.
The principle of convex mirrors is no stranger to everyone. Some convex mirrors at the corners of the road can provide us with another view. That's because the convex mirror shrinks the rear-view object, thus expanding the rear-view range and viewing angle. The method that once appeared was to directly install a small convex mirror on the side rearview mirror. However, to do so, from the outside, it is really ugly, and it is easy to be removed (the editor's old Santana encountered it), and it cannot truly reflect the size and actual distance of the object behind the car, so this approach Soon it was ruthlessly abandoned by the market. However, the advantages of convex mirrors are reflected in another technology, which is the double curvature mirror technology.
The principle of dual curvature mirror technology: According to the three elements of the vehicle model, the position of the driver’s eye point and the relative position of the rearview mirror, and the field of view requirements, using optical principles and data methods, different radii of curvature are selected for different viewing angles of the front, rear, left, and right of the vehicle, and smooth transition. In this way, it is possible to further expand the field of vision and reduce the blind spots under the condition of basically no distortion, which not only meets the national mandatory standards, but also solves the problem of blind spots. In addition, the demarcation line is used in the design of the mirror to warn the driver that the variable curvature surface is only for observing the general situation behind the car. It is an innovative advancement in the design of rear view safety, but the manufacturing process is more complicated and the manufacturing cost is expensive. .
Double-curvature mirrored rearview mirror, the middle 2/3 area uses a flat mirror, and the outer 1/3 area uses a large arc convex mirror, so that the driver can see a panoramic view behind the car and eliminate blind spots when turning. The field of vision has tripled. On the one hand, it better compensates for the too small rear view range of the flat mirror. In addition, due to the larger radius of curvature of the convex surface (around SR2000), the distortion problem is basically solved.
It not only ensures the compact appearance of the rearview mirror, but also provides the driver with a wider field of view, and also solves the problem of convex distortion. Therefore, the dual-curvature mirror technology is the undisputed king of automobile rearview mirror technology.
I have already introduced you to the uncrowned king of rearview mirror technology—double curvature mirror technology. Today we will talk about another technology that is closely related to your night driving safety, anti-glare technology.
Drivers who often drive know that the biggest safety hazard when driving at night is the line of sight problem, not only the low visibility at dark, the short visible distance, but also the light from the headlights of the oncoming cars. When the rear vehicle is driving with the high beam for a long time, the dazzling glare will be reflected into the driver's eyes through the rearview mirror of the car, affecting the driver's driving safety. Therefore, in order to reduce the occurrence of danger, another kind of science in rear-view mirrors was born, which is the anti-glare technology of rear-view mirrors. Anti-dazzle rearview mirrors are generally divided into anti-dazzle inside rearview mirrors and anti-dazzle outside rearview mirrors.
At present, there are two main anti-glare methods for car rearview mirrors, which are traditional coating technology and new electronic anti-glare technology.
Common rearview mirror mirror coatings include silver plating, aluminum plating, inscription plating, and TiO2 coating (blue mirror). Silver-plated and aluminum-plated mirrors have high reflectivity. Although they can be seen clearly, long-term observation of the mirrors is likely to cause eye fatigue, and the anti-corrosion performance is poor, prone to oxidation, and low cost. The reflectivity of the chrome-plated mirror is more suitable for eye irritation and has better anti-corrosion performance. Most of the rearview mirrors currently in use adopt this kind of coating method. The TiO2 coated mirror can interfere with the dazzling high-wavelength visible light and convert it into blue light, which is the most suitable light for human eyes to achieve the anti-glare effect. However, the processing technology is more complicated, the cost is high, and the stability of chromatic aberration is difficult to control.