Blocked situations increase stress. . . . Where S represents the starting point, and T represents the target, there are loops of trains of thought all around S within the blocked matrix. Unfortunately, T is located outside the plane of the matrix.
—ARTHUR KOESTLER, The Act of Creation
INVENTORS ARE OFTEN SURROUNDED by hidden barriers. The inventor may have created a fantastic opportunity or pinpointed a question that urgently must be solved, but this doesn’t mean that he or she knows the right path to a solution or even whether such a path exists. Many of us have had that feeling that we’re running in circles, banging our head against a wall, or hitting up against an obstacle that seems insurmountable.
Successful inventors tend to thrive on this kind of stress. They know that the only way to work through the obstacle and the anxiety it produces is identify the stumbling block in a way that others who have approached the problem have yet to see. At some point, the inventor will feel trapped in a vast maze, and the only way to escape is to find a hidden passageway, discover a door in the floor, or realize that the maze itself exists in three dimensions rather than two.
Kathryn Wilder Guarini faces just this kind of challenge. Guarini, a dark-haired woman with a calm, easygoing demeanor, is one of the younger members of the research staff at IBM’s Watson Labs. Working on opening up a third dimension in the world of semiconductors, Guarini is up against a range of physical barriers. In accordance with Moore’s Law, the famous principle set down by Intel founder Gordon Moore, the number of transistors we can pack into a square inch of microchip has been doubling roughly every eighteen months for more than three decades. Thanks to breakthroughs by hundreds of researchers and inventors in dozens of companies, we can now fit more than 200 million circuits onto a fingernail-sized chip that can process more data more quickly than could the room-sized computers of yesteryear. But we need a way to transcend that matrix. “We’re going to need some new kinds of breakthroughs,” says Gerald Marcyk, director of components research at Intel. “The single-dimension path of the past thirty-five years is now limited.”1
Guarini’s approach is to add another dimension. “With current microchips, there is only a single layer of active devices,” she says.2 Whereas others are plunging into new areas of scientific discovery—attempting to build “molecular computers” by lining up individual atoms or to design “optical computers” by arranging photons of light—Guarini is working with conventional technology. But instead of trying to pack more transistors onto the same surface, she is asking the question, “Can you have more than one layer of transistors?” she says. “It’s like making a layer cake. We need to build or grow a new layer on top of the first one.” It sounds simple enough. The only problem is that it has never been done successfully, and no one knows whether it’s possible.
Guarini thrives on the challenge of detecting and working through these kinds of barriers. Growing up in Connecticut in the 1970s and 1980s, she enjoyed puzzles, mind games, and math problems. In high school, she was inspired by an enthusiastic physics teacher who would leap on top of a desk and declare, “Physics is life!” Guarini went on to major in applied physics at Yale and received her Ph. D. in the same field from Stanford, where she studied under the coinventor of the atomic force microscope. She worked as an intern at Hewlett-Packard before joining IBM at the age of twenty-six in 1997.
As Guarini sees it, the stumbling block to creating 3-D chips must lie somewhere in the manufacturing process, in microscopic construction techniques. As you try to add a new layer to a chip, “you can damage or degrade the layers below.” She has made real progress in addressing that barrier using scanning probe lithography, a method of manipulating nanoscale transistors. At an international conference in December 2002, she presented a newly patented technique for adding a new layer of circuits without destroying what lies beneath.
Given that her employer receives more patents than any other corporation in the world, it’s no surprise that Guarini is listed as coinventor on several interesting patents such as this one. But none of those patents represents the smashing of a really big barrier. “I don’t think that we have had an epiphany or a breakthrough yet,” she says. “We try to outline what the major roadblocks are, and we will try to mow them down one by one. We might know whether this or that is a potential challenge or a potential roadblock. Only then can we come up with an innovative solution.”
Like a chef baking layer cakes, Guarini dons a white hat and uniform for her daily duties. Hers, however, is a bright white bunny suit that covers every inch of her head, hands, body, feet, and clothing. She takes a visitor into the “cleanroom” where she conducts her 3-D semiconductor experiments, checking on crystals that are growing in vacuum chambers and peeking at silicon wafers that are baking in ovens that typically crank up to 900 degrees centigrade. Guarini works with robotic arms to manipulate acid bath tanks, spin dryers, and electron microscopes. “We look for microscopic bumps,” she says. “We spend a lot of time on the art of measurement: How do we see what we made?”
Only by detecting what is happening at the nanoscale level will she be able to overcome what she now sees as the next set of barriers: the process of connecting the circuits between the two layers so that they work as one microchip. “The goal is to make the layers work together,” she says. “That hasn’t been done yet.”
Detecting barriers can be frustrating work. By looking around at her colleagues wandering the halls of the crescent-shaped Watson Labs headquarters in Yorktown Heights, New York, Guarini can see what the stakes are. The danger here isn’t losing your job; there aren’t very many applied physicists on the unemployment line. Instead, the danger is falling into obscurity. Some researchers work their entire careers in a single problem area without making a significant breakthrough. Others, such as Guarini’s colleague Bernie Meyerson, detect and overcome a significant barrier and go on to become laboratory superstars who are promoted to the top of the organization.
“I have an opportunity to make a mark,” Guarini says. “But this is the nature of corporate research. Breakthroughs are rare. You have to study what others are doing and try something a little differently.”
Sometimes it takes only one person to detect a barrier that is holding up an entire bureaucracy. By trying to do something a little differently, a young inventor named Isaac Berzin thinks he may have found such an obstacle. Berzin, who has lively dark eyes, a quick laugh, and a slight Israeli accent, works in a basement laboratory just off the campus of MIT, where he’s attempting to invent what he believes will be the cheapest form of commercial power and the cleanest-burning fuel known. If what he is doing works as planned, Berzin’s renewable biofuel will leap ahead of wind power, photovoltaic cells, and hydrogen fuel cells to become the leading contender to replace coal, oil, and nuclear power in the world’s electrical power plants. That’s a big claim, but Berzin knows he will have to overcome an even larger series of hidden barriers to realize this possibility.
Berzin is growing a specially modified form of algae and turning it into what he calls GreenFuel. He’s talking about the stuff that clings to the walls of fish tanks—the stuff that requires only water and photosynthesis to breed right before your eyes. “Photosynthesis,” Berzin says. “That’s how all of nature survives. The division time of algae cells is measured in hours. It’s very tolerant of everything. You can find it in the Charles River, in sewage, in boiling water, in ice, in Antarctica, in fresh water, in the Dead Sea.”3 By infusing algae with carbon, the key source of the energy locked inside coal, Berzin believes he may be able to turn this plentiful, naturally growing plant into a source of power.
Researchers at the U.S. Department of Energy (DOE) have known about this carbon-algae possibility for years. The department’s experiments, however, involved growing algae in an open pond and pumping carbon-based gases into the pond’s water. As it turns out, this is an inefficient and ineffective way to grow the algae. Only the top of the pond receives sunlight, and it receives too much. This means that the pond must be churned by heavy machinery, itself a process that requires energy. And harvesting the carbon-infused algae from the pond is itself an expensive process. As a result, Berzin says, the pond-based approach isn’t scalable or cost-effective. It simply isn’t worth doing, and any new form of energy must be cost-effective to be successful. There needs to be a cheap and highly controlled way to grow and harvest massive amounts of algae. This was the barrier that Isaac Berzin detected while reading reports of these past experiments.
The son of an inventor, Berzin grew up in Israel and received his Ph. D. in chemical engineering from an Israeli university. In 2001, he began his postdoc work in the MIT laboratory of Robert Langer, a prolific biomedical inventor whom the Boston Globe recently called “the smartest man in Boston.”4 When Langer saw what Berzin was proposing, he helped set up the GreenFuel project in the offices of Payload Systems, a 10-year-old NASA contractor that has been developing a process to cultivate and harvest hydroponically grown plants in atmospheres other than that of Earth. Langer has long been MIT’s faculty adviser to Payload.
Near the bottom of the creaky wooden staircase in Payload’s basement, Berzin constructed a set of three biofuel reactors. He has filed for patents on the basic approach. Each reactor is built around a long Lucite tube filled with water, and the tubes sit under a series of full-spectrum lightbulbs. The other inputs to the reactors sit in tall pressurized tanks. One tank is filled with carbon dioxide, and the other is filled with nitrogen oxide. Both are well known as pollutants given off by power plants. Anyone who can recycle these gases can receive “credits” under set of DOE regulations devised to reduce greenhouse gases. In the world of energy, these credits are as good as cash. As a result, any cost of producing GreenFuel can be offset by these pollution credits, and this is one reason it promises to be cheap.
The chemical reaction is simple. The artificial sunlight hits the water and produces algae. At the same time, the CO2 reacts with the N2O in the algae-filled water. As a by-product of this reaction, oxygen is released into the room, and pure nitrogen is piped out of the building through an exhaust system, where it mixes with the outside air. (Nitrogen is harmful when it is part of a compound with oxygen; that compound is the main ingredient of smog. But releasing pure nitrogen into the outside air isn’t harmful. It gets absorbed by plants. Nitrogen itself is the main ingredient of fertilizer.)
The key here is the carbon; it gets trapped in the algae. Berzin’s reactor pushes the carbon-infused algae to one end of the plastic tube. This mixture is then harvested and pumped to another room by means of desktop-sized machines that Payload built for NASA in cooperation with MIT’s spaceflight program. These miniature automated bio-reactor systems (MARS) essentially convert the green watery sludge into a dry crystalline powder. The result is a green chunky substance that consists mostly of carbon. When it burns, the substance produces 90 percent of the energy of carbon-based coal.
Unlike coal, however, GreenFuel yields energy without any harmful emissions. In fact, the process of making it actually consumes harmful emissions, so much so that coal plants become the perfect place to create and burn GreenFuel. The substance can even be sprinkled in with coal, and they can burn together. Needless to say, the coal industry will probably be highly skeptical. “I’d like to find a way to work with them,” Berzin jokes, “or else they will kill me.”
By detecting a barrier in the process of producing and harvesting carbon-infused sludge, he seems to have achieved a breakthrough that had escaped the attention of an entire bureaucracy and all the corporations that do business with it. Berzin believes that his cheap GreenFuel process is infinitely scalable. Whether he is right is a huge question. To prove the idea, he must build more reactors and place them side by side. At first, the process was being conducted in a basement under artificial light. But Berzin is planning to launch his first pilot project out in the open, with the sun as the source of the photosynthesis.
Berzin has found some early believers in his initial breakthrough. His business plan for GreenFuel won $10,000 as the runner-up in the MIT $50K Entrepreneurship Competition, an annual contest for student-led start-ups. That recognition helped Berzin land a round of venture capital investment in 2004 and move his company, GreenFuel Technologies Corporation, into a larger office space in Cambridge. With those funds, Berzin plans to conduct pilot projects at several steam and power plants.
Berzin may have detected and overcome one major barrier, but he’ll know for sure whether he is on the right path only if he is able to detect others. “I’m like a little duck learning to swim,” he says. “Maybe I’m starting to fly a little.” But he realizes he can’t go it alone. Scaling up his system is going to be an enormous task. Eventually, Berzin wants to grow GreenFuel in the sun-drenched Great Plains of the United States. “I’m going to need to connect with people in ten different fields to get this out into the world,” he says.
Orville and Wilbur Wright may be history’s most remarkable example of having what it takes to detect the right barrier at the right time. In the most simplified understanding of what the Wright brothers accomplished, there is the tendency to ascribe to them the very idea of the airplane. Nothing could be further from the truth. Birds have served as mental models for future flying machines since the days of Leonardo da Vinci. “The wind may serve as a wedge to raise them up,” he wrote. In 1738, Daniel Bernoulli gave future inventors an equation for understanding the relation between pressure, velocity, and elevation. But applying Bernoulli’s principle wasn’t enough for inventors to achieve the proper liftoff. Something else, some other lack of understanding, was standing in the way of the invention of the airplane as we’ve come to know it.5
The Wrights are often portrayed as garage tinkerers—bicycle repairmen—who empirically tried various approaches to solve the problem of powered flight, learning only from trial and error. This, too, is misleading. The Wright brothers studied the theory of flight and pondered why others had failed. They constructed a wind tunnel and performed sophisticated simulations before trying to take flight themselves. But they achieved what they did for a key reason: They detected the exact barrier that had eluded other aeronautical pioneers and then focused intensely on overcoming it.
Rubber band–powered toy helicopters made of cork, bamboo, and paper had already been around in various forms for at least a century when Dayton, Ohio, minister Milton Wright presented the toy to two of his young sons. The year was 1878. Wilbur was nine, Orville seven. The brothers noticed the remarkable stability of this toy’s flight pattern. But when they built their own model helicopters, they were surprised to learn that that the bigger they made them, the more unstable they became.
As young men, the Wright brothers were interested in all sorts of things, including developing their own photographs and editing and printing their own newspaper. Those other interests faded after Orville borrowed three dollars from his older brother to buy his first bicycle, the kind with an oversized front wheel and a high saddle. Soon after, they each bought new, more expensive “safety” bicycles, in which the two wheels were of the same size. The innovations in bicycle design—including sprocket chains replacing direct pedaling, air-filled rubber tires, and comfortable seats—triggered a national craze in the 1890s. In anticipation of a continued surge in demand, in 1892 the brothers opened a shop for bicycle assembly and repair.6
They continued to read occasional articles about others who were tackling the problem of manned flight, mainly from the point of view of amateur enthusiasts. One story in August 1896 especially struck them. German flight pioneer Otto Lilienthal, who had built eighteen variations of his hang glider over six years, was hit with a sudden gust of wind while in flight. He thrust his body to compensate, but he wasn’t able to avoid a sideslip, and he plunged to his death.
This was the same year the first horseless carriages came to Dayton. But the Wrights weren’t impressed by the automobile or interested in its early limitations. They were fascinated by bicycles and by the perplexing problem of flight.
Because neither of the brothers went to college, one might assume that they knew little of the science behind the problem. But they studied their chosen challenge even more voraciously than a typical academic. Both had equal parts intelligence and mechanical skills, and both worked as closely as two people had ever worked, applying what has been called their “dual gift” to their objective. Assembling and repairing bikes by day, in their spare time they searched for books on the subject of flight. In the summer of 1899, they wrote the Smithsonian Institution for references to available flight literature. (No, they weren’t referred to airline magazines.) In the letter, Wilbur stated, “I am an enthusiast, but not a crank.” Until then, the Wrights had been reading mainly about ornithology, the study of birds. Now, with the references provided by the Smithsonian, they learned about the aviation experiments of those who had come before them.
They read the works of Lilienthal and those of Octave Chanute, author of Progress in Flying Machines. They also read about Alexander Graham Bell’s experiments with multidimensional kites and about Hiram Stevens Maxim, who had invented the machine gun before taking up this new problem. They also read a translation of Louis-Pierre Mouillard’s L’Empire de l’Air, which Wilbur called “inspiring.”
The Wrights were not interested in gliding but rather in powered flight, and they were not interested in balloons, only in “heavier-than-air” flight. The literature developing around the problem as they saw it wasn’t voluminous, but the Wrights investigated everything of importance, searching for holes in theories and for assumptions that might be incorrect, much as a modern-day inventor will scan patent filings and peruse technical journals for similar gaps and gaffes.
Probably the most daring of the experimenters was Samuel Pierpont Langley, the secretary of the Smithsonian. To Langley, the barrier was in powering the plane. In 1896, Langley launched a dual-wing, twin-propeller plane, powered by a steam engine, from a bluff by a bank of the Potomac River. He called his craft an aerodrome, and he improved on his design by adding an ingenious lightweight engine. Bell, by then famous, was on hand to take photographs of Langley’s first flights. Of course, Langley’s early aerodromes were unmanned, so his achievements don’t rival what the Wrights later accomplished. But at the time, Langley was the man who had proved wrong the professors and experts who claimed to have scientific proof that heavier-than-air flight was impossible.
In reading about Langley, however, the Wrights concluded he was heading in the wrong direction. They were surprised by how little attention was being paid to the problem of controlling the aircraft. Who cared about the engine? Langley had no way to steer the plane. They observed how birds controlled direction and steering, whereas others had focused on how birds achieved lift and aerodynamic glide. The airplane, the Wrights imagined, would have more in common with the bicycle, which requires delicate, constant steering, rather than the automobile, in which the breakthrough was in the engine. In their reading, they took note of Chanute’s call for “a better way to maintain equilibrium than by thrashing the legs and torso about—gyrations made necessary by wind fluctuations that caused the center of pressure on a wing to move back and forth.”7 To the Wrights, the term powered flight was misleading. Powering the aircraft would be relatively simple. The engine could come later. What use is an engine if you can’t control the aircraft?
That was the barrier they detected: one of maintaining control and balance. “We at once set to work to devise a more efficient means of maintaining the equilibrium,” wrote Orville.8 That was the stumbling block that had foiled previous inventors, although they didn’t realize it until they saw the Wrights redefine the problem.
The result was a discovery known as “wing warping,” a technique for stabilizing the plane by controlling the position of the wings. The idea of twisting the wings became the basis for the most valuable and contentious patent in the history of aviation. Orville had the inspiration one day while fiddling with an empty bicycle tire tube box, twisting each end in the opposite direction. The brothers then applied this analogy to their latest flier, and in December 1903, the Wrights made history with their breakthrough flight at Kitty Hawk. But they never would have had anything to break through if they hadn’t detected the critical barrier in the first place.
Within established industries, lots of inventors often converge on the same barrier at roughly the same time, and it takes a little extra juice to be the individual or team to be the first to break through. Carl Crawford has got it. He was one of a handful of inventors to discover a critical boundary at the core of the medical equipment business, and he is constantly searching for new ones. Crawford is slightly built with thinning light brown hair, and he acknowledges that he’s “somewhat weird, like most inventors I know.” A bicycle enthusiast who likes to get up early to go for a ride every morning, he sometimes becomes so preocupied with technical problems in his mind that he forgets where he is or how he got there. Growing up in Milwaukee in the 1960s, Crawford recalls spending hours ripping apart and repairing transistor radios.9 He also remembers his family’s shock upon getting his SAT results: a 200 on the verbal portion, the lowest possible score, and a near perfect 790 on the math portion. “I couldn’t communicate,” he says. That has since changed, but Crawford still points to these scores as evidence of his quirkiness and his reliance on having his inventions speak for him.
While Crawford was studying electrical engineering at Purdue, a professor interested Crawford in computed tomography, or CT. At first, Crawford says, “I couldn’t spell CT.” Not long after receiving his Ph. D. from the same institution, he took a job in his hometown of Milwaukee as a staff engineer with GE Medical Systems. At GE, he was struck by the limitations of commercial CT scanners (sometimes called CAT, or computer-assisted tomography, scanners). The technology was already a mainstay of the conglomerate’s medical equipment business. A vast improvement over the film-based X-ray machine, which took only a two-dimensional snapshot, CT provided superlative three-dimensional images of the body’s interiors. If something important, such as a tumor, was blocked by bones or other organs, the X-ray machine would often miss it. With CT, though, doctors could finally see everything in graphic detail.10
The technology had revolutionized medical diagnostics to such an extent that its inventor, Allan Cormack, and the engineer who commercialized it, Godfrey Houndsfield, shared the Nobel Prize in medicine in 1979. By then, these SUV-sized machines had been installed in hospitals all over the developed world, at a cost of about $1 million each. A patient, lying on a conveyer, was carried through the contraption much as a piece of paper is fed through a fax machine, except that the scanning occurred in three dimensions. The scanner acquired cross-sectional images of the head and body and then reassembled the slices and rendered them as images for study by doctors. Indeed, the Latin root tomo means “slices.” Typically, the slices would be only ten millimeters thick, so the machine had to acquire hundreds of them.
But these machines had a drawback: It often took several minutes to scan an entire body. Each thin slice had to be rendered as perfectly as possible. The slightest movement by the patient, including something as simple as breathing, would cause blurring or streaking in the images. As a patient moved through the scanner, technicians had to pause each time the scanner arrived at a new section of the body. To get a proper scan, patients had to hold their breaths during each scan to prevent artifacts and gaps. “How long can a person hold their breath?” remarks Crawford. “For twenty seconds, maybe thirty or forty, if you’re really healthy.” Between scans, the patient was typically allowed to breathe for only six to eight seconds.
Inventors around the world had been working to improve the machines for years, trying to detect barriers and work through them. First-generation scanners were based on a single X-ray detector that rotated and translated around the cross sections. This process often took more than an hour, and it required such stillness from patients that early CT scanning was limited to the head. Later scanners employed an array of detectors. Now each slice could be acquired in several seconds. This improvement opened up new applications for scanning not only the head but also the neck, chest, abdomen, pelvis, legs, and feet. But most hospitals had only begun buying these machines when they started to come equipped with hundreds of detectors. This reduced scan time even further per body section, but the problem remained of patients having to hold their breaths, notes Crawford, and many of the images still ended up with some blurring and had to be redone.
After joining GE, Crawford spent large chunks of time reviewing the technical literature, a habit he continues to this day. To detect a new barrier, and therefore a new opportunity, he searches for flaws. They often present themselves as holes in logic. “I look for assumptions that might be wrong,” he says. “I also look for adjectives and adverbs. They often hide the fact that the writers don’t understand fully what they are writing about.”11 In articles about CT scanners, he found an interesting logic gap. Previous inventors had believed that the solution was to incorporate increasing numbers of X-ray detectors into these machines or to rotate them faster around the body.
Crawford, however, hit up against a different obstacle. “History said the patient had to be completely stationary,” he says. “That was impractical.” He believed that the ultimate CT scanner should scan sections of the body in less than one second. In this way, the patient wouldn’t have to worry at all about blurring due to moving or breathing.
Others hadn’t seen it that way. Back in the mid-1980s, the barrier to instantaneous scanning was thought to be the time it took for the X-ray tubes to cool or by limitations on data bandwidth. “We made the assumption that data acquisition was not limited by those factors,” he says.
Crawford and a fellow engineer named Kevin King were especially focused on the problem. Like the Wright brothers, Crawford and King were not far apart in age, and they developed an effective way of working together. When one got burned out thinking about something for too long, the other would pick up where the first one left off. By bouncing ideas off of each other, they discovered a previously unseen opportunity: Why not find a way to acquire the image data continuously, rather than in discrete slices and intervals? Why not find a way to scan sections of the body in a single breath hold so that blurring is no longer an issue? Why not reduce the time between scans to zero? These were radical questions at the time. “We had to cross this threshold,” Crawford says. In heading down this new path, Crawford and King reinvented the challenge. They set out to create a new machine that would scan the body in a new way.
To solve the problem, they homed in on the scanning pattern itself. If the patient was moving, they thought, the X-ray detectors would no longer be able to capture a perfectly cut slice of the body. Instead, it would be like winding a string around a slowly moving cylinder. The detectors would actually be acquiring a continuous spiral pattern. The scanning pattern would resemble a Slinky toy rather than slices of salami. Along with the new pattern, there needed to be a new mathematics for translating data taken from a moving patient in this way.
The two engineers had detected the roadblock, but they didn’t yet know how they were going to get around it. “That was the barrier,” Crawford says. “We created our own necessity just by looking at the problem in a different way.” They were determined to come up with a new method of scanning and not a better way to conduct the old method. They viewed the existing scan pattern, fixed for the preceding twenty years, as obsolete.
In an internal GE paper in 1987, Crawford and King first described their resulting solution, based on a breakthrough interpolation algorithm. They called their invention “helical extrapolative scanning.” Also known as spiral CT scanning, the technology was first introduced to the industry in 1989 and then perfected in the early 1990s, when it would lead to what Stanford University radiologist Sandy Napel called a “virtual renaissance in CT, improving its capabilities in existing applications and creating new ones.”12 By the mid-1990s, virtually all CT scanners would be spiral scanners.
But Crawford and King weren’t the only ones who detected the same barrier. As is typically the case, they were simply among the first. Simultaneous invention was happening all over the world. That is the nature of barrier detection. Inventive minds tend to converge on good ideas. In the days of the Wright brothers, the pace of invention was far more rapid than it had been in all of history. But at least the Wrights had a few years to work through their barrier before others caught up with them.
Crawford and King had no time at all. Other inventors and corporate researchers were on the road toward a similar result. In their patent search, conducted along with GE attorneys, they came across a 1989 University of Illinois patent by inventors headed down a convergent path. They also discovered a 1986 patent, filed in the United States by a Toshiba engineer, that referred to helical scanning. But the biggest source of competition came just as Crawford and King were getting ready to file their own patent applications and as they were preparing a paper for submission in the journal Medical Physics.
In June 1989, Crawford went to Berlin to attend an industry conference. It was there that he met his counterpart at the medical systems division of Siemens, the German industrial giant. Electrical engineer Willi Kalender was part of a Siemens team readying its own patent applications, as well as a paper on spiral CT scanning, for the journal Thoracic Radiology. The two groups knew of each other but didn’t know exactly what the other was working on. One late night, Crawford and Kalender met and went out for a drink. The most convenient bar happened to be located in a nearby brothel. It was there, over beers in that less than reputable establishment, that Crawford said something like, “I am working on the best thing, something that will revolutionize CT, but I can’t tell you what it is.” Hearing that, Kalender replied with something like, “So am I!” They sidestepped their secrets for the rest of the evening, beer after beer, trying to talk about other things.
In the subsequent months both teams filed for patents and submitted papers.13 By the end of 1990, the patents and papers of both teams had been published, and their work was no longer secret. At that year’s radiology conference in Chicago, each team summarized its work and discussed the results back to back, in the same room, on a Sunday morning. First, Kalender, from the Siemens team, spoke about spiral scanning. King, from the GE team, followed with his presentation on helical scanning, a minor difference in terminology that continues to be argued about.
With both teams detecting the same barrier and announcing similar breakthroughs, one might think that the race to market would have been intense, but that wasn’t the case. Instead of supporting the findings of their own engineers, the management of GE Medical Systems went on the attack against this new method of scanning. GE denounced the approach taken by Siemens as well as the approach taken by Crawford and King. “GE was scared about cannibalizing” its existing market, Crawford recalls. At the time the world leader in selling the current million-dollar machines, the GE division was led by managers and marketing executives who figured that word of a revolutionary new approach could kill their current pipeline of product sales, significantly impacting near-term revenue. They assigned other GE executives to write papers claiming that this new form of CT scanning wouldn’t work, according to Crawford.
Siemens took the opposite approach, rushing a new-generation product to market in early 1991. The Siemens product started capturing some market share, at the expense of GE. But according to Crawford, Siemens had released its machine prematurely because it incorporated the wrong algorithm for interpolating the spiral scan data. Kalender seemed to encounter a significant new barrier. The Siemens engineer was unable to correct for a mathematical effect of the spiral scanning process, and this led to a doubling of the scan time. That defect slowed Siemens from further penetrating the market, as Kalender and his team tried to figure out how to overcome this more specific problem.
Crawford and King, meanwhile, hit this new barrier hard. What was this more specific barrier? As it turns out, helical scanning until then was based on collecting data in half-scans of approximately 180 degrees. One set of X-ray detectors scanned the top half of the body, and a second set scanned the bottom half. With the spiral scan pattern, the body moved too fast to get this approach to work without producing image artifacts. Crawford and King, in a separate patent filed only two weeks after their first one, disclosed something new: a method of having all the X-ray detectors acquire data in full, 360-degree scans around the body, thereby obtaining two measurements of everything. The double measurements were used to cancel out the image artifacts and retain the time goals. “Our invention was in doing it without doubling the scan time,” Crawford says.
This was the breakthrough that eventually caused a massive changeover in a rich market. Within two years, the results from these new spiral scanners were proven to be so superior that everyone became convinced. Even those within GE protecting the status quo had to acknowledge that the new spiral CT technology was here to stay. Within ten years, everything had been replaced. By now, virtually all the CT scanners in use worldwide are helical, or spiral, scanners. According to the National Electrical Manufacturers Association, some twenty thousand of these machines were sold in the 1990s. At about $1 million each, that’s $20 billion in revenues.14
The machines opened up new applications, such as virtual colonoscopies, in which a patient’s colon seems to become the setting of the latest Pixar movie. Entrepreneurs began buying the machines to circumvent the existing healthcare system, opening CT scanning centers in malls and storefronts, typically charging about $1,000 for a full body scan that can detect tumors as small as three millimeters wide in any organ. A recent study in the New England Journal of Medicine showed that CT scanners can now display such precise renderings in detecting colon cancer that they can serve as accurate replacements for invasive and expensive colonoscopy procedures.15
As these case studies show, the barrier that is blocking a new invention is often more complex than it may seem at first. Finding the obstruction that is holding back a valuable improvement can set off a backlash inside a corporation or an industry before the new invention ever gets a chance to disrupt the market. As such, detecting barriers can be considered dangerous, even subversive, behavior. Once that obstacle is out of the way, however, inventors can see their way more clearly.