Rear View Mirrors

So how exactly do they work? I was driving home today and noticed a little switch on the bottom of it, and when I flipped it it made almost every thing black (as to shield the light from cars behind you), but how is this? Just by changing the angle ? It looks like the mirror is pointed twords the backseat, but yet is creating a black mirrored image of what is behind me. I was kind of deboggled by this, if anyone has the scientific know how as to why this does this, i'd be greatly appreciative.

Thanks,
Drew

 

Here is an article that explains how those things work: http://auto.howstuffworks.com/question20.htm

Enjoy!

 

Man, I was just gonna ask this same question. My bunk ass car does'nt have that though

 

All the switch does is tilt it for you, if you dont have a switch you can achieve the same affect my SLIGHTLY tilting it, its better to tilt it UP for 'night vision' then down..that way you get the roof superimposed instead of the backseat passengers

 

^^Na, some of the really expensive cars actually tint your mirror. I've even heard that some do it automaticly, but I don't know about that. Drewbee, what do you drive? My jeep just tilts the mirror, but some tint.

 

'02 Saturn SL... That car is so going to break alot

 

Thanks for the link, that is some pretty crazy stuff... lol Never knew light could do that... neat

 

A switchable tint is obtained using Electrochromic layers. An electrochromic layer (Tungsten Oxide for example), will change its optical properties when in the presence of ions. Typically an electrochromic layer and an ion source (with something to separate them) is sandwiched between glass substrate. When a potential is applied the ions are moved towards the electrochromic layer, changing its reflecivity/absorption.

 

It changes the light spectrum. Like a prism does. Very simple. You learned about that in the third grade.