What is the Principle of Anti-glare Rearview Mirrors?
2 Answers
Anti-glare rearview mirrors come in manual and automatic types. Below is an introduction to the principles of these two types: 1. Principle of manual anti-glare rearview mirrors: The mirror of a manual anti-glare rearview mirror is not a flat mirror with uniform thickness, but rather a wedge-shaped mirror with an angle of approximately 10°. When the anti-glare lever is pushed forward, the entire mirror surface tilts upward by about 10°. At this point, what we observe is only the semi-transparent light-transmitting coating of the rearview mirror. This coating has a lower refractive index to light, thus providing a certain anti-glare effect. 2. Principle of automatic anti-glare rearview mirrors: An automatic anti-glare rearview mirror consists of a special mirror, two photodiodes (front and rear), and an electronic controller. The electronic controller receives signals from the front and rear photodiodes. If the rear photodiode detects stronger light than the front photodiode, the electronic controller outputs a voltage to the conductive layer of the rearview mirror. This conductive layer then changes the color of the mirror's electrochromic layer (the higher the voltage, the darker the color). As a result, strong light reflected by the anti-glare rearview mirror appears as dim light to the driver's eyes, preventing glare.
I've always found the anti-glare feature of car rearview mirrors very useful, especially when driving at night, often being dazzled by the headlights from behind. The principle is actually quite simple: the rearview mirror is designed with two layers of mirror surfaces, and you can switch angles by manually flipping that little lever. In the normal position, it reflects strong light intensely, but when switched to the anti-glare position, the mirror tilts slightly, making the light reflection less direct, thereby reducing the brightness, just like wearing sunglasses. This manual method is energy-saving and durable, and my old car uses it—it's effortless to operate. Modern cars even have automatic versions that use sensors to detect strong light and automatically dim. This feature is not only convenient but also much safer, helping to avoid accidents caused by being blinded by glare. In short, remember to try that little lever; it makes driving steadier.
