Photo-chromatic or Transition Lenses darken when exposed to sunlight. This happens due a chemical reaction that takes place when glasses are exposed to sun light. You can read more about it at HowStuffworks.com its awesome website if you want to learn about how basic things around us work. Anyway…

Do you have tinted windows for your car? They are great while driving during the day but try parking a car with tinted windows at night and its a pain in the ass. The problem is that with tinted windows I can’t see anything especially when I am looking back and trying to parallel park at night in the streets of San Francisco.

So, here’s the idea….. why don’t automobile manufacturers uses Photochromatic glass for rear windows of cars??? That way my windows stay “tinted” or “darken” during the day time and at night since there is no sun, the windows become clear and thus making it easy for drivers to park and drive around.

I know it might be expensive to implement but it would be good product offering for luxury car manufacturers such as Mercedes Benz, BMW, Lexus etc and quite frankly I would pay little extra $$ for that luxury feature.