Automatic dimming rearview mirror principle: It has two photodiodes, a mirror mounted on the front, a rear surface, respectively receiving the front and rear cars to light emitted. When the car headlights is incident on the interior rearview mirror, two photosensitive diodes of the signal from the comparator based on the light intensity at the front of the back light, the electronic controller would then apply a voltage to the mirror ionospheric mirror, it will become darker in color, to the back of the light emitted will be absorbed by a large part of the mirror, the remaining light rays reflected on the eye of the driver becomes much softer.
Although capable of dimming mirror automatically dimming, but when reversing out of the garage, since the strong light behind the car and the car in front of the light is weak, such as the mirror case not darken after reversing the situation conducive to see when the car, some cars it is designed to automatically canceled when the vehicle reverse gear dimming function, or may cancel the manual switch function. More entries Atlas Atlas