Math professor's side mirror that eliminates 'blind spot' receives US patent

phys.org ^ | June 07, 2012 | Provided by Drexel University

[Red Badger]

A side mirror that eliminates the dangerous "blind spot" for drivers has now received a U.S. patent. The subtly curved mirror, invented by Drexel University mathematics professor Dr. R. Andrew Hicks, dramatically increases the field of view with minimal distortion.

Traditional flat mirrors on the driver's side of a vehicle give drivers an accurate sense of the distance of cars behind them but have a very narrow field of view. As a result, there is a region of space behind the car, known as the blind spot, that drivers can't see via either the side or rear-view mirror. It's not hard to make a curved mirror that gives a wider field of view – no blind spot – but at the cost of visual distortion and making objects appear smaller and farther away.

Hicks's driver's side mirror has a field of view of about 45 degrees, compared to 15 to 17 degrees of view in a flat driver's side mirror. Unlike in simple curved mirrors that can squash the perceived shape of objects and make straight lines appear curved, in Hicks's mirror the visual distortions of shapes and straight lines are barely detectable.

Hicks, a professor in Drexel's College of Arts and Sciences, designed his mirror using a mathematical algorithm that precisely controls the angle of light bouncing off of the curving mirror.

"Imagine that the mirror's surface is made of many smaller mirrors turned to different angles, like a disco ball," Hicks said. "The algorithm is a set of calculations to manipulate the direction of each face of the metaphorical disco ball so that each ray of light bouncing off the mirror shows the driver a wide, but not-too-distorted, picture of the scene behind him."

Hicks noted that, in reality, the mirror does not look like a disco ball up close. There are tens of thousands of such calculations to produce a mirror that has a smooth, nonuniform curve.

Hicks first described the method used to develop this mirror in Optics Letters in 2008 (http://dx.doi.org/10.1364/OL.33.001672).

In the United States, regulations dictate that cars coming off of the assembly line must have a flat mirror on the driver's side. Curved mirrors are allowed for cars' passenger-side mirrors only if they include the phrase "Objects in mirror are closer than they appear."

Because of these regulations, Hicks's mirrors will not be installed on new cars sold in the U.S. any time soon. The mirror may be manufactured and sold as an aftermarket product that drivers and mechanics can install on cars after purchase. Some countries in Europe and Asia do allow slightly curved mirrors on new cars. Hicks has received interest from investors and manufacturers who may pursue opportunities to license and produce the mirror.

More information: The U.S. patent, "Wide angle substantially non-distorting mirror" (United States Patent 8180606) was awarded to Drexel University on May 15, 2012.

Journal reference: Optics Letters

Provided by Drexel University

[Red Badger]

A side-by-side comparison of a standard flat driver's side mirror with the mirror designed by Dr. R. Andrew Hicks, mathematics professor at Drexel University. With minimal distortion, Hicks's mirror shows a much wider field of view (the wide area to the left of the silver car seen in the distance, behind the tree, in this image). Hicks's mirror has a field of view of about 45 degrees, compared to 15 to 17 degrees of view in a flat mirror. Hicks's mirror received a US patent in May 2012. Credit: R. Andrew Hicks, Drexel University

[Red Badger]

[Red Badger]

[ClearCase_guy]

The story of this invention is going to be turned into a major motion picture starring Sandra Bullock ...

[Red Badger]

If she’s in it, I’ll watch anything.............

[Elderberry]

I just put one of those 2 in. concave stick on mirrors on each side mirror.
Problem solved.

[Poser]

Um... Those 99 cent spot mirrors I have on my vehicles are better.

[GOPJ]

This will save the lives of many motorcyclists...

[Revolting cat!]

Why did take 2,000 years, I axe?!

[DManA]

I can adjust my mirrors right now so there’s no blind spots.

[R. Scott]

I learned to eliminate the “blind spot” years ago when I was a cab driver.
Tilt your head to the left and adjust the mirror like usual. When setting straight it covers the “blind spot”. When changing lanes – or just checking behind you – look in the mirror then tilt your head.
Of course some people are too lazy to do it.

[Sea Parrot]

Hell, I have used stick on fish eye mirrors on all my vehicles for years, and they work just fine too.

[Da Bilge Troll]

What “blind spot”?

As I explained to my kids when I taught them to drive, the mirror in the middle is the rear view mirror. The ones on the sides are for the SIDES.

[martin_fierro]

[null and void]

Hmmmmm. Is it just me or does the silver car look much further away in the new mirror?

What's his problem with the "Objects in mirror are closer than they appear" label on his precious mirror?

[SpaceBar]

Pretty amazing. One would think that after a few hundred years with analytic geometry and geometric optics available, someone would have figured this out years ago, but I guess not. My hat’s off to the inventor.

[knarf]

Those back up cams have the same problem ... what looks like almost on top of a parking bumper is still 3 ft away.

[Slings and Arrows]

Why did take 2,000 years, I axe?!

Paperwork.

[Straight Vermonter]

The mirror is not legal on the driver’s side with or without the label.

[null and void]

Ah. Thanks!