There's a problem with most of the highway signs currently being used in the U.S.: Overglow. The signs are fairly legible in the daytime, but at night, when they're illuminated solely by the reflected light from car headlights, reading becomes trickier. A New York Times article and accompanying slideshow (via Mike the Mad Biologist) demonstrates the problem:
What was clear text during the daytime becomes an illegible blob at night. The problem, it seemed, was the tiny spaces inside of letters -- the loop of an "a" or an "e," for example. At long distances, at night, and particularly for elderly drivers, these characters became difficult to distinguish. But the U.S. highway administration doesn't change fonts on a whim. How do you determine if a prospective font is superior? The first step is almost more about aesthetics than science:
Researchers analyzed fonts used in highway signs around the world, but each presented its own problems. Eventually they realized they'd need to design an entirely new font. The candidate that emerged was Clearview, designed by Don Meeker and James Montalbano. Their new font avoided overglow by expanding the size of those open spaces, and by adding a few extra distinguishing elements such as a small hook at the bottom of lowercase "l"s. You can see the difference in these two sample signs. Clearview is on the right:
The next step is testing. The initial test was done in as realistic a setting as possible:
Intrigued by the early positive results, the researchers took the prototype out onto the test track. Drivers recruited from the nearby town of State College drove around the mock highway. From the back seat, Pietrucha and Garvey recorded at what distance the subjects could read a pair of highway signs, one printed in Highway Gothic and the other in Clearview. Researchers from 3M came up with the text, made-up names like Dorset and Conyer -- words that were easy to read. In nighttime tests, Clearview showed a 16 percent improvement in recognition over Highway Gothic, meaning drivers traveling at 60 miles per hour would have an extra one to two seconds to make a decision.
The final version of the font improved on these numbers even more, for over a 60 percent improvement in legibility in certain circumstances. The Clearview font has now been approved for highway use by 20 states. Look for it on a road sign near you soon!
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Ah, the progress of free markets.
I'm gonna claim ownership of the period and the question mark.
I love reading stories like this about fonts, for some reason! They're like the perfect example of industrial design, but with aesthetic issues that everybody agrees on and scientific issues that nobody understands.
I think this is an interesting article that only exposes a part of the problem with reflective signage. Isoluminance and isochrominance as much to the point of readability or lack thereof as font, although I was intrigued by the story. Thanks.
I am so glad I can blame the illegibility on the font! I thought it was another example of the inevitable middle age decline.
From my (Swedish) perspective this is a big no-issue. Why not keep the old signs and let them fall to the ground when their time is up? That way driving will be made harder and more people will get lost. In the long run people will leave their environmentally harmful unnecessary SUV:s etc at home and perhaps use public transportation instead. No more roadsigns! ;)
I know you aren't serious, Johan, but it seems the DOT is implementing that plan anyway. 200+ bridges in my state are in disrepair (the study was prompted after the bridge collapse in MN.) I see the problem is in advertising (nothing we can do about it except raise public awareness, it's still a free market here,) and in the re-relaxed emission standards of 2005 on so called "Sport-utility Vehicles."
I would be the most unpopular Governor for my plan would be to tax the hell out of owners of SUV's and implement higher gas taxing, both would deter excess driving and force the issue for many people - consumerism or conservation. I would tax gas to record highs, $5-6 a gallon, which would still be well below the European average. I'd also implement mandatory emission checks for all vehicles since only about 7-11% of the vehicles on the road are responsible for 50% of greenhouse emissions! I figure if the President can get away with slaughtering thousands of people based on a lie then anyone should be able to get away with this plan.
Sorry Chris, I totally missed your comment on my comment. You really seem to be on to some good politics! I think I would vote for you if I had the opportunity. Then of course we could always discuss what a free market really is, and where it is the most free...