I'm no proponent of the nanny state, but there is something to be said for standards. It's important that any driver be able to drive any car. Otherwise, a driver used to 1:1 mirrors who rented or borrowed a car with convex mirrors would underestimate the speed and distance of cars passing him.
It's actually the opposite, objects in the mirror may be closer than they appear. In fact they are closer, this is for the passenger side mirrors. Cars always look farther away in it than in the driver side mirror or in the middle rear-view mirror
I just Googled around for objects in the mirror may appear closer than they are and objects in the mirror may be closer than they appear. Two totally different things. Thousands of results.
Which one is actually true? Surely if objects are further away than they appear, it's pointless to note that since it's safe. So it has to be "Objects in the mirror may be closer than they appear" right?
Convex mirrors will produce a smaller virtual image (behind the plane of the mirror) taken from a wider field of view. Concave mirrors will produce an inverted real image (for objects farther away than the focal length) or a larger virtual image (for objects inside the focal length).
Much along the same idea, coming out of the Ferry Building in San Francisco a few days back when it was pouring with rain, someone had helpfully put out cones to warn me that I was entering the outside and that it was wet. The black sky, and cats and dogs falling from it might have also tipped me off, but thankfully I had the cones as confirmation :)
My first inclination would have been to solve this sort of stuff by digital manipulation.
But on second thought, once built, it's a static piece of hardware that essential does a single compose-able image transformation that requires no processing power--almost like a pre-processor. It just doesn't handle the requirement if the transformation has to change from moment to moment.
Or you can say, these mirrors do calculation by reflecting lights in specific ways---it's real-time, continuous calculation. Electronic digital circuits aren't the only way to calculate.
They say it in the article... the mirror's curve is calculated to cause the light to be bounced more than once before being reflected to the viewer - so it's more like several mirrors, except they're built into a single physical object that looks like a mirror.
a guy called Michiel Kassies holds a european patent on a structure like that, this was obtained somewhere in '86 so in europe probably at or near expiry. I don't know how to find European patents online otherwise I'd look it up, filing date was probably late '85 or early '86.
The thing was wedge shaped for better aerodynamics but looked from the inside of a car like a normal side mirror. No clue anymore how the thing worked exactly except that it was lots and lots of thin sheets with all kinds of interesting properties.
The guy who designed these has a webpage here: http://www.math.drexel.edu/~ahicks/. One of the links on the page lead to more information on the design of the mirrors.
