People who carefully observe life will find that there are some small black spots on the windshield of the bus we usually take, while there are also some small black spots in private cars. What are the special functions of these small black spots? Today I collected some information to answer for you.
There are also many statements. Some say it is used for road electronic eye focusing, some say it is the sensor of automatic wiper, and some say it is the sensing area of automatic headlamp, etc. These statements seem likely, but what I say is that they are wrong!
We will carefully find that these small black spots are distributed on many windows, and their corresponding functions are different according to their positions.
Behind the center rearview mirror:
It can play the role of sunshade. There are sunshades and black spots in the central rearview mirror, which can prevent the sun from interfering with the driver's line of sight.
Windshield edge:
The black spots on the edge of the windshield can not play the role of shading. Its role is mainly to protect. We know that the heat absorption capacity of glass is stronger than that of car body. The front windshield is usually fixed on the car with glue. When the car is irradiated by strong light, the surrounding of the glass will expand with the increase of temperature, and the heat of the middle glass is not as high as that of the surrounding edges because it is transparent.
This leads to different expansion of the glass, which is likely to cause damage to the glass. However, with these small black spots, the heat around the glass can be reduced and the temperature difference around and in the middle of the glass can be balanced, so there will be no large difference in expansion, which also protects the glass in disguise.
Now everyone knows the role of these small black spots after reading them. Will you also be surprised that ordinary small black spots have such a "magical" role? This also confirms the saying that "existence is reasonable".