Today, I decide a story is worth telling. The
University of Houston's College of Engineering
presents this series about the machines that make
our civilization run, and the people whose
ingenuity created them.
Several friends have lately
said to me, "Do a program about the bar code --
about those zebra stripes on retail goods." I've
been saying, "Yeah, yeah. Maybe someday."
Then it hit me: the bar code was invented at the
wrong time. It was no spawn of the computer age.
Two engineering teachers at Drexel cooked it up in
the late 1940s. That was back when computers still
used radio tubes, and only government labs had
Bernard Silver overheard his dean talking to the
president of a supermarket chain. The fellow wished
he could automate pricing at checkout counters.
Silver went to his friend, Joe Woodland. He said,
"Let's figure out a way to do that!"
Their first idea was to read colored fluorescent
dots with ultra-violet lights. But that limited the
range of prices they could handle. Then they hit on
the idea of reflecting light from black and white
bars. But how could they do that, no matter which
way the product passed the light? They finally
patented a bull's eye pattern of concentric circles
The year before that, Woodland joined IBM. IBM
studied the scheme and found that lighting sources
and computers were still too primitive. The system
would cost too much. So Woodland worked in other
areas for several years. He studied optical
character recognition, xerography, and computers.
Then, in 1959, when integrated circuits and lasers
came of age, IBM went back to develop a bar-code
system. The grocery business was finally ready to
adopt it in the late 1960s. Between '70 and '74
they agreed on a standard form of Woodland's code.
By now, a criss-cross laser system could read
parallel lines instead of a bull's eye. Grocery
stores finally started using the system almost 30
years after it was conceived.
Most modern technology grows out of itself.
Computers suggest their own improvements.
Transistors and lasers fairly scream to be used in
new ways. The invention of the bar code was
different. Two smart men went into resonance with a
good idea. Woodland committed himself to it. He had
it on the shelf waiting for the support technology
that would make it work.
So my friends were right. The bar code story is a
useful one. It helps us find the line between real
invention and development. The bar code was radical
enough to be unusable at first. Unlike most radical
ideas, this one succeeded because its inventor
stayed with it. My friends were right on this one.
The invention of the bar code really is a parable
for our times.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds