What is the purpose of the dotted line on the rearview mirror?

[DiMicah]

The dotted line is the dividing line of a dual-curvature rearview mirror, which helps reduce the driver's misjudgment of the distance of vehicles behind and allows observation of both closer and farther positions on the side of the vehicle. The smaller section to the right of the dotted line has a magnifying effect, while the larger section to the left is a standard mirror surface. The reflection angles differ on either side of the dotted line, which means that when changing lanes to the left, the field of view becomes significantly smaller, creating a larger blind spot. The small area of the dual-curvature rearview mirror may also feature a small indicator, which serves as a "side blind spot warning system." When there is a potential collision risk on the side of the vehicle, this indicator will flash to alert the driver. If the body of a vehicle behind has entered the danger zone to the left of the dotted line on the rearview mirror, it indicates that the following vehicle is very close, and lane-changing should be avoided at this time. If the left side of the following vehicle's body is close to the boundary between the safe zone and the danger zone, the driver should remain vigilant, but turning with signals is still safe at this stage. If the following vehicle is in the safe zone, located in the center of the rearview mirror, it means the distance between the two vehicles is about 15-20 meters, and normal lane-changing operations can be performed. Functions of the dotted-line rearview mirror: A rearview mirror with a dotted line is called a dual-curvature rearview mirror, divided into two main sections by the dotted line. The dotted line is located at the outer third of the mirror, with the inner section being the normal reflection zone, also known as the standard rearview mirror area. This area provides a nearly 1:1 reflection with minimal distortion. The outer section has a higher curvature, offering a wider field of view, which helps drivers better adjust their vehicle position. For example, during reversing, the wider curvature allows for a broader view of the reversing area. The entire dual-curvature rearview mirror acts like a small convex mirror, expanding the driver's field of vision. Due to its compact size, the dual-curvature rearview mirror helps reduce wind resistance and improve fuel efficiency. It also includes an alarm system that alerts the driver when there is a potential side collision risk, prompting them to take evasive action. Most vehicles also feature rearview mirror heating. In special weather conditions, activating this function prevents fogging, ensuring clear visibility. During heavy rain, applying a rain repellent to the mirror can be helpful. Rain repellent forms a thin film on the glass surface, allowing water droplets to slide off quickly. This product can also be used on the windshield. Care should be taken to avoid scratching the rearview mirror, as its plastic housing is difficult to repaint. When parking on the roadside, folding the mirrors is recommended.