https://www.youtube.com/watch?v=tI3cR9KhrdY
With the amount of tech in new cars, we sometimes don't even bother to try and understand how it all works, but if you ever wanted to start you should look at the modern marvel of the auto dimming rear view mirror. This has been around for a few decades now, but it's still as impressive as ever.
Some may not even know it, but when you are driving at night and need to look in your rear view mirror, most cars now have a feature that darkens the mirror as to reduce the glare and allow you to see what's going on back there.
The auto dimming mirror, technically named "Electrochromic Mirror," works using two light sensors. One is at the back of the mirror facing the windshield and it detects ambient light. The other is at the face of the mirror and detects light from the rear of the car like another car's headlights behind you.
The auto dimming mirror also contains a control unit. When glare is detecting during a low light situation like night time a small charge is sent to the electrochromic mirror. The mirror is actually a clear piece of glass with a mirror behind it. In between is an electrolytic film that darkens when ions are sent from an ion storage layer to the electrochromic layer during a process called "Electrochromism." This allows for little light to travel from the clear glass to the mirror and greatly reduce glare.
It's pretty cool, and surely has everyone saying, "Once you go electrochromic, you never go back."
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