A View from David Zax
A Side-View Mirror without a Blind Spot
Disco balls inspired a mathematics professor’s design.
A professor of mathematics at Drexel University has designed a side-view mirror that could eliminate the “blind spot.” The only problem? Regulations would prevent it from being directly integrated in the production of cars sold in the United States.
The mirror was invented by Andrew Hicks, and awarded a patent last month. The mirror strikes an optimal middle ground between flat mirrors (the ones on the driver’s side) that don’t distort objects, and curved mirrors, which present a wider field of view but cause distortion. Hick’s mirror gives something of the best of both worlds: a wider field of view with little distortion. (It remains true, though, that objects in Hicks’s mirror are closer than they appear.)
Bizarrely, the trick to designing such a mirror is similar to the principle of a disco ball. “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.” For the optically and mathematically inclined, see this paper from 2008 describing just how the technique works.
A Philadelphia Inquirer story from 2009 reveals how it has actually been an eleven-year journey to this patent. It all started when a colleague came in complaining about a rear-view bicycle mirror. Hicks had a prototype ready by ’09, and had developed other novel mirrors as well, including a panoramic mirror, mirrors especially designed for security cameras, and “mirrors with odd, undulating surfaces that are fashioned with a computer-guided milling machine.”
It’s intriguing how highly computerized the process is, per the Inquirer:
“…armed with a computer, Hicks can customize his creations with exquisite precision. He achieves the desired effect first by characterizing the problem with sophisticated equations. He then programs a computer to spit out the coordinates for tens of thousands of points on the mirror’s surface - each one tilted differently to reflect light in just the right way.”
It’s a good thing Hicks is producing a portfolio of mirrors, because if he intends to make a business of his designs, he may have better luck in a funhouse than with the giants of car manufacturing. There’s a law against curved mirrors on the driver’s side of a car. Overseas markets might prove a better fit.
“I’m not naturally an entrepreneur,” Hicks told the Inquirer. He might want to team up with someone who is. It’s clear his innovative technique has potential, in some product, in some market, somewhere. Whether his mirrors belong on the side of cars or elsewhere, someone with “the vision thing” will have to determine.