[Piwoslaw]

I'm afraid that making such a large magnifying lens inside would be very hard (=expensive). People are made in many different sizes and shapes, so the optical system would have to work at many different angles and distances to be useable by both for the grandma that leans far forward almost touching the steering wheel with her chin, and for the teenager sitting very low and far away from the wheel.

Hmm, after a moment of thought, I think I've heard about something similar, only with a prism instead of two lenses. It stuck out a little to collect the image which was later reflected onto a 'screen' on the inside of the door. I have absolutely no idea where I saw this, though.