The rearview mirror is a tool for the driver to directly obtain external information such as the back, side and bottom of the car while sitting in the cab seat. In order to facilitate the driver's operation, prevent traffic accidents and ensure personal safety, all countries stipulate that rearview mirrors must be installed on cars, and all rearview mirrors must be able to adjust the direction.
The rearview mirror does not need to look at the rear tires. The rearview mirror has a vision problem, that is, the range that the mirror can reflect. There are three visual elements in the industry, namely, the distance from the driver's eyes to the rearview mirror; Dimensions and radius of curvature of rearview mirror. There is a certain relationship between these three elements. When the distance and size of the rearview mirror are the same, the smaller the radius of curvature of the mirror, the larger the field of view reflected by the mirror. When the radius of curvature of the mirror is the same, the larger the size of the mirror, the larger the field of vision reflected by the mirror.
The birth of rearview mirror
As one of the oldest parts in the car, rearview mirror has been born for more than one hundred years. The appearance of rearview mirrors is a historical necessity, just like the windshield, the tilt angle of the steering wheel and the rubber tires. Without it, the car wouldn't be what it is today.
At the age of 23, the legendary British female racer Dorothy Levi drove a Desdions car with a speed of 1905, which set a record for the highest continuous mileage of female racers. Then she broke the women's highest speed record with 1906, and was praised as "the fastest woman in the world" at that time.
Because of the special work of racing drivers, Dorothy often deals with cars. The unique sensitivity and delicacy of women make her realize that she can't observe the surrounding situation intuitively in the car, which will make pedestrians and drivers themselves very dangerous. So she put forward the idea of observing the situation behind the car with a mirror in the manual Thewomanandthecar published by 1906, which is the prototype of the car rearview mirror. Despite this idea, it's a pity that racers didn't put this great idea into practice.
In the first Indy 500 race of 19 1 1, Ray Harron, an engineer and racer of Marmon Company in the United States, installed a simple rearview mirror in his car and won the championship. After that, many drivers began to follow suit, but in general, rearview mirrors were not widely used outside the stadium.
It was not until 192 1 that an inventor named ElmerBerger patented the rearview mirror, named it "COP-SPOTTER" and started mass production in his own company, and the rearview mirror was officially born.