Ok, so maybe this is obvious or dumb topic to most of the members here, but I for one get a kick out of finding-out little details and sharing with the community.... Case in point: Auto-dimming mirrors.

The auto-dimming feature on automotive mirrors has been around for a long time, so this post isn't claiming to have discovered the location of Jimmy Hoffas body or anything like that.... (I don't need anyone schooling me on the history of these things or anything! I just wanted to share this with those who like me love to tinker and play around with things around us to understand them! )

For those that like to get technical, I seem to recall that the auto-dimming feature is made possible by taking advantage of modern electrochromic technology. Maybe the technology has changed in recent years, but this was how I understand they worked at some point. Electrochromic materials are those that change color when an electrical charge is provided. Each mirror has electrochromic gel between two pieces of glass and equipped with sensors that detect the intensity of glare from trailing cars' headlights. Based on the level of glare, an electrical charge is released causing the gel to darken and the glass to be effectively tinted. The darkening of the gel is commensurate with the intensity of glare detected.

I was sitting in my C4S in the parking lot the other day, waiting for the next train, and noticed for the first time that my mirrors have a dark blue area clearly visible. It is early morning, bright, so I am guessing the sensors picked-up on the brightness and since I had the ignition on the electrochromic gel darkened.

I had never before paid much attention to the mirrors, or how they dimmed, or when -- but this got me curious. So I grabbed my iPhone, and crudely captured the color changing through a couple of cycles turning the ignition on and off. As you watch the video, you can see the color change in moments.... I thought this was cool!

 

I find the darkening background quite noticeable on the Porsche but not at all visible on my Audi or Touareg. Interesting that they are different. You would think the technology is all the same.

 

Awesome! Never paid attention long enough to notice.

 

Oh, so that's where SEPTA is spending money on train parking lots. Out here on the Main Line we got nada..nothing, just a scramble for the few unleaded spots for those who hop on the Paoli Thorndale line....