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Stanford and Volkswagen Unveil An Autonomous Race Car

Yesterday, on the Stanford University campus, researchers unveiled Stanford’s third generation autonomous vehicle, a modified Audi TTS. Unlike Stanley, the university’s first generation self-driving car, and Junior, the second generation autonomous vehicle, this latest model won’t be competing against entries from other teams for millions of dollars in prize money, for the era of challenges sponsored by the Defense Advanced Research Projects Agency (DARPA) is over. Too bad for the Stanford researchers, because Stanford did well in the past, placing first in 2005 with Stanley and second in 2007 with Junior, both developed in cooperation with Volkswagen of America.

“The challenges were exciting,” said David Stavens, a PhD student in computer science who co-designed Stanley. “They inspired us to come together and advance the field.” And he will miss them. But on the plus side, without specific criteria and deadlines to meet, researchers now, Stavens said, “have a moment to step back and look at the whole problem,” which may lead to new insights. And, for Stavens personally, he’ll finally get to focus on writing his Ph.D. thesis and graduating.

Stavens did hint that some of the former competitors may be coming together to figure out a way to fill the vacuum created by Darpa stepping out of the autonomous vehicle challenge business, but couldn’t be convinced to say more.

Stanford’s latest autonomous vehicle, pictured above and right, is designed for the racetrack, not city streets. It zips along at the highest speeds it can manage and still stay in control. The sensors and algorithms built to do this will, researchers hope, eventually enable ordinary cars to operate more safely by knowing their limits and forcing drivers to stay within them.

The car will go through its paces live tomorrow as part of the dedication of the new Vehicle Automotive Innovation Laboratory at Stanford’s School of Engineering. Volkswagen Group of America donated $5.75 million to fund the lab, including $2 million for the building and $750,000 a year for five years to fund research and teaching.

Clean Tech Open Announces 2009 California Finalists

Today in Palo Alto, Calif., the 2009 Clean Tech Open honored six teams of entrepreneurs as California Regional Finalists. The competition began in 2005 as the California Clean Tech Open. This is the first year the competition extended outside the state; the California winners will go on to compete with finalists from other regions.

Still, being named as a California finalist—out of a field of 158 entries—is huge, and the folks picked today knew it. Four competitors sitting in front of me were literally holding their breaths waiting for the award in their category to be announced—and simultaneously exhaled when they heard their company’s name. It’s such a big deal because California finalists get $100,000 in cash and services to help them build their businesses, and because being named a finalist is validation of their ideas that brings them one step closer to getting the venture investment they need to make their dreams come true.

The California Regional Competition sends six teams on to the finals, one in each of the competition categories—Air, Water, and Waste; Energy Efficiency; Green Building; Renewables; Smart Power; and Transportation. The Pacific Northwest and Rocky Mountain competitions will each send three finalists on. A National Grand Champion will receive a $250,000 prize package.

While all six finalists announced seem to have solid business potential, two in particular generated a distinct buzz in the room when founders stepped up to describe their ideas—not chatter, exactly, but that feeling of the folks in the audience leaning forward just a bit to make sure they’re catching every word, the rustle of people rummaging for a pens to take notes.

Based on this buzz factor, I’d say the California startup with the biggest chance at the Grand Prize is Micromidas. The team, mostly recent graduates from the University of California at Davis, has developed a technology that turns raw sewage into biodegradable plastic. They intend to work with wastewater treatment companies to build the processing plants to produce the plastic. The plastic would be sold as packaging material for retail goods; consumers would the dispose of the packaging in home or municipal composting facilities. The price of the new plastic would be competitive with petroleum-based plastics. Micromidas is looking to raise $1 million in funding and expects have its first pilot plant up and running a year from obtaining that funding.

Also a possible Grand Prize contender, based on the audience buzz: Armageddon Energy. This solar-power-kit-in-a-box company actually grew out of the Clean Tech Open itself; its founders met as volunteers behind the scenes, where they helped set up chairs and click through slides, and then started talking about what it would take to enter the competition themselves. The team has designed a 1-kilowatt rooftop solar system designed to be sold in a flat-pack box and through big box retailers like Home Depot and Costco. While consumers could do some of the assembly and installation themselves, the final step—connection to the electric grid—would require an electrician to complete, although that electrician would not need any special solar installer certification. Along with the system, the company would sell dashboards and web services for consumers interested in closely tracking system performance.

The other California finalists were Alphabet Energy, tru2earth, Ecofactor, and Fuelsaver. National winners will be announced at an event in San Francisco on 17 November.

Read Spectrum’s coverage of past winners:
Crowning the Clean Tech Stars
California Clean Tech Open Wraps Up for 2007
Build a Kite Big Enough for a Ship and You’ll Save Fuel
Winner of Clean Tech Open Scores Again


Nobel Controversy: Willard Boyle denies Gordon's claims, proud of CCD work

Editor's Note: This is part of our ongoing coverage of the 2009 Nobel Prize in Physics. Read more about the Nobel Prize winners themselves, the Bell Labs engineer who patented the CCD imager, and the illustrious history of Bell Labs.


Last Monday, I asked Willard Boyle, who will share the 2009 Nobel Prize in physics with former colleague George Smith, a few uncomfortable questions:

Should Eugene Gordon have been on the patent for the CCD?
“I don’t think so. I don’t see it all. He didn’t have any entries in a notebook... I’ve no recollection of his having been around.”

Should Mike Tompsett be recognized for making the first CCD camera?
“Fair enough. He’s one of the three that made the first model. No problem there.”

What about those who complain that there is no physics to the invention of the CCD—that it’s purely a work of engineering?
“They should complain to the Nobel Committee. We’ve already had a nice engineering award for it.”

In a conversation with me it didn’t seem that Gordon’s claims had dented Boyle’s happiness in the least. I asked him what the week of the announcements was like:

“It’s been extremely busy,” says the retired Haligonian. He described the 05:00 wake up call from Stockholm as “a shocking moment.” His wife answered the phone: “Stockholm is calling.”

Since the call he’s been in contact with fellow winner George Smith: “We’re both happy. You get a nice comfortable feeling,” he says. (Several hundred thousand euros would indeed be comforting, in my opinion.)

Recalling the day he and Smith worked on the CCD concept he says that when he came home that night he told his wife: “George and I did something special today.”

Years later, he and Smith received a series of letters from major observatories around the world, thanking them for their work. “It made you feel good,” he says. He’s looking forward to going to Stockholm to accept the award.

Nobel Controversy: Smith dismisses Gordon claims, heard it all before

Editor's Note: This is part of our ongoing coverage of the 2009 Nobel Prize in Physics. Read more about the Nobel Prize winners themselves, the Bell Labs engineer who patented the CCD imager, and the illustrious history of Bell Labs.

(This was updated on 19 October.)


Did Eugene Gordon give George Smith the idea for the CCD? “Absolutely not,” says Smith. The Nobel Prize winning engineer says Gordon has made such claims before. “Needless to say, I get a little stirred up when I hear them.”

Gordon, Smith's boss at the time, says he gave Smith the concept behind the CCD.

Regarding the Boroughs paper Smith says: “This is a new one on me. He's made other claims before, but not that one.” Because Gordon has made claims against him before, Smith was ready to produce documents (at least, the first page of documents) he says show Gordon's signature under statements that Boyle and Smith invented the CCD.

(The quality of these documents is not so good, but they are mostly readable. They are from the 1970s and also are scans of faxes sent from Boyle's home in Halifax some time ago.)

At first read, these documents are not exactly decisive-none say anything like: “Boyle and Smith invented the CCD. Sincerely, Eugene Gordon”-but they are highly suggestive. (Smith informs me that the word invent would probably not be used before the patent is granted, anyway. Instead inventors would be called "originators.")

In a 6 November 1969 memo to Bell Labs patent lawyers from Gordon using the words "recent ideas by Boyle-Smith" with regard to the CCD. A memo dated the day before says that "W.S. Boyle and G.E. Smith described a technique [the CCD]". A third dated 23 October 1969 is also to a patent lawyer, but makes no statement that Smith and Boyle (or anyone in particular) are the inventors (or originators), merely that if the lawyer needs more information he should contact Smith and Boyle.

However, Smith calls the October letter the most decisive, because it is the original patent submission regarding the CCD. I'm following up to find out if there's some patent-speak meaning to being named in that section.

The memos are also fascinating in their own right, because two of them  focus on the idea of using a CCD as a display device rather than as an imager—an idea Smith credits Gordon with.

After dismissing Gordon's claims, Smith walked me through the invention of the CCD as he remembers it. The way he tells it, it's origins were strongly tied to the desire to build a better bubble memory. Sailing buddies Smith and Boyle worked in Bell Labs semiconductor division at the time, with Boyle in charge. Magnetic bubble memory was under development by a different division and “was a very hot item at the time.” Smith recalls Boyle worrying to Smith that funding for the semiconductor division would be diverted to magnetic bubble memory unless they could come up with a competing concept.

What followed was their magical afternoon's work. “A lot of people work for years and year and it never works out,” says Smith. “There's a certain amount of luck involved.”

Nobel Controversy: Eugene Gordon Claims He Gave Smith The Idea for the CCD

Editor's Note: This is part of our ongoing coverage of the 2009 Nobel Prize in Physics. Read more about the Nobel Prize winners themselves, the Bell Labs engineer who patented the CCD imager, and the illustrious history of Bell Labs.

IEEE Fellow and CCD camera chip inventor Mike Tompsett has already called into question the validity of Smith’s and Boyle’s claims to this year’s Nobel Prize in Physics, now his former Bell Labs boss, IEEE Fellow and Edison Medal Recipient Eugene Gordon, is backing Tompsett’s position and striking even deeper at Boyle’s and Smith’s contributions to as the Nobel Prize committee called it “the invention of an imaging semiconductor circuit—the CCD.”

“This is an outrage,” says Gordon. Tompsett invented, designed and built the first CCD camera, he says. “Smith had little to do with it. Boyle had nothing to do with it.”

What’s more, in a wide-ranging telephone interview Friday, Gordon told me that he gave Smith the concept behind the CCD, even going so far as to hand him an article by other researchers at Burroughs describing a similar shift register concept for a display device, before “sending him off to work out the numbers.”

The Borroughs paper described a shift register for moving a spot of light based on a three-phase clock. When combined with what Gordon’s group had already learned developing a silicon-diode-based video camera target, there was no great leap of logic to go from that idea to the CCD, he says. “We already knew about storing charge in the space charge gap between the oxide layer and undepleted semiconductor substrate. In that region you can move accumulated or stored charge many centimeters,” he says. All one had to do is set up voltages in a phased clock format to move the charge along “There was nothing to it except the numerical details.”

Smith worked out those details with the man who was Gordon’s boss at the time, Willard Boyle. And the two patented a CCD intended as a kind of bubble memory. Gordon’s name was left off the patent, without his knowledge.

“I had a fit, but there was no point in fighting my boss or destroying the patent for Bell Labs,” says Gordon. “That was just one more invention. I have a hundred patents myself.”

Gordon didn’t talk publicly about the events surrounding the invention for many years, while Boyle and Smith’s standing solidified. During the 1970s he was busy developing the electron beam photolithography mask maker still used in IC fabrication, and in the early 1980s he worked on the semiconductor lasers needed for transoceanic communications. Moreover, he could not speak about the CCD because he was advising Toshiba in their legal battle with Fairchild Semiconductor regarding the technology.

Long retired from Bell Labs, today, Gordon is the CEO of medical device firm Germgard Lighting, in Dover, N. J. It’s an “exciting” time for the business, which makes sterilization equipment to prevent hospital acquired infections, says Gordon.  So last week was “not as upsetting as you might think” for him.

So who should have gotten the Nobel, in Gordon’s opinion?

“It really shouldn’t be a physics award,” he says “Most of the work has been in electrical engineering. There’s no fundamental physics.”

If it had to go to someone for the CCD, it should have gone to Mike Tompsett alone, Gordon suggests.

“The whole thing is an outrage. But such outrages are perpetrated all the time.”

IEEE Spectrum hopes to be speaking with Willard Boyle and George Smith soon. Stay tuned.

Nobel Controversy: A Portrait of Bell Labs in the Mid-1960s

Editor's Note: This is part of our ongoing coverage of the 2009 Nobel Prize in Physics. Former Bell Labs engineer Eugene Gordon claims he gave George Smith the idea for the CCD. Read more about the Nobel Prize winners themselves, the Bell Labs engineer who patented the CCD imager, and the illustrious history of Bell Labs.

Gordon gave me some background on what was happening at Bell Labs at the time, that puts the invention in context:

In the mid-1960s, AT&T wanted to move from providing what’s called plain old telephone service (POTS) to offering businesses network services. The Federal Communications Commission, Gordon recalls, turned them down. AT&T’s plan B was to come up with an offering that would give them a back door into network services. They’d make a video telephone system; claim that it was merely an extended telephone service, which would be allowed by FCC, and sneak in broadband network services, because the Picture phone required broadband lines. The new service was called PANS (Picturephone and network services). Julius Molnar was the architect and he was brilliant.

The camera tubes of the day worked fine in television studios, but the uncontrolled lighting in an office environment easily blinded them. (The technology’s amorphous antimony trisulfide imaging targets were the problem.) Gordon says that he was given the responsibility to develop a camera tube that would not have the bright light burn-in problem of conventional vidicons. In early 1967 he had an idea for a silicon diode array picture camera tube that should do the trick.

Nobel nominee Willard Boyle, who was not his boss at the time, “crapped all over the idea and refused to help even though he had the lab and people who could build it,” he says. But Gordon, working through another part of Bell Labs, persevered.  He and his team had a product that went into manufacture in 1969. (One of the tubes was used to record the Moon landing that year, because it was impervious to the bright sunlight that had ruined other Apollo camera tubes.)

Gordon says he gave Smith the shift register idea following a gathering of the camera tube team Gordon had called to congratulate everyone on moving the camera tube on to manufacturing at Western Electric. “If Picturephone had been a success,” says Gordon. “The camera tube would have been replaced by Tompsett’s CCD camera.”

Sensor Nation, UK Style

At the time of the July 2005 London bombings, the average Londoner was on camera an average of 300 times a day. That didn't prevent an attack, of course. Surveillance cameras — the UK had an estimated 4.2 million of them in 2005 — can help the police solve a crime after it's committed, but no one is looking at them in real time.

A organization named Internet Eyes would change that. It has developed a scheme that would allow ordinary citizens to watch CCTV (closed-circuit television) video streams and sound an alarm when they see things that are, well, alarming. Internet Eyes holds out a reward of £1000.

According to the BBC report that broke the story, today London has "one camera per 14 people" and yet the police have "estimated that in 2008 just one crime was solved per thousand CCTV cameras in the capital. The deficit was partly blamed on officers not being able to make the best use of the many thousands of hours of video generated by CCTV."

It's hard to imagine the Internet Eyes program, which is slated to begin next month in Stratford-upon-Avon, will do much to improve that. While news reports make it sound as if all you have to do is see a crime and report it to collect your £1000, the reality is a lot more complicated and a lot less lucrative.

Viewers are anonymously monitoring random video feeds streamed from privately owned establishments. At no time can Viewers designate or control the video feeds they receive and the locations of the feeds are not disclosed.

The instant a Viewer monitors an event, an alert can be sent directly to the owner of that live camera feed. The alert is sent along with a screen grab, identifying the image you have observed. Only the first alert received by the camera owner is accepted.

The camera owner will then feedback (rate) the result of the alert. Their feedback is converted into points and entered into a Viewers monthly league table. At the end of each month the highest scoring Viewer will receive the reward money; this could be split in the event of a tie.

Viewers register for free with no recurring fees. Each Viewer has 3 x alerts per month allocated to their account for free. Viewers are able to ‘top up’ their alerts through PayPal if they so desire. The free allocations of alerts are limited to prevent system abuse.

So, for one thing, you don't get to choose your feed. Even if you would probably be a more attentive viewer viewing your own neighborhood or a favorite store, you probably will never get that chance. Then, your success depends on the utility rating the camera owner gives to the alert you send — that, plus an opaque points program. Finally, only a single thousand-pound prize is awarded, no matter how many crimes are "solved" by CCTV alarms that month. (Oh, and having to pay for your own alarms after the first three — nice touch. Still, people pay for their votes on American Idol, without any prospect of an award, so maybe they'll pay to play here as well.)

"Solved" is in quotes because it's not clear what it means for a crime to be solved by a CCTV camera. Back in August, privacy expert and security entrepreneur Bruce Schneier noted,

To me, the crime has to have been unsolvable without the cameras. Repeatedly I see pro-camera lobbyists pointing to the surveillance-camera images that identified the 7/7 London Transport bombers, but it is obvious that they would have been identified even without the cameras.

Then there's the question of how well people will assess that a crime is being committed by seeing a few seconds of grainy video stream by their eyes. Football referees often can't determine that a facemask was grabbed, or that a foot stepped out of bounds, when they watch higher quality video streams than those of the average street camera.

The BBC report noted that crimes aren't noticed in real time today because "viewing hours of mostly tedious and often poor quality images is a lengthy and unpopular job." If that's true when people who are doing it receive a regular paycheck, does it get any less tedious when done in the hope of a windfall hardly more likely than winning the lottery? (Still, people pay good money to engage in the same repetitive motions that factory workers have complained about for decades, in the hope of hitting a slot-machine jackpot.)

If the program is unsuccessful, few people will be watching. but if the program is successful, will the camera owners, and ultimately the police, have enough staff on hand to evaluate an alarm quickly enough to apprehend a suspect at the scene of the crime? It seems unlikely. The bottom line is that probably some people will watch the video streams, the police will be alerted to a couple of crimes, and Londoners' privacy will continue to erode.

Exactly one year before the London bombings, Spectrum published a special report entitled "Sensor Nation." In an article entitled "We Like to Watch," my colleague Harry Goldstein presciently wrote,

For entertainment, we gather in front of the tube for mass-mediated group therapy sessions called reality shows. Hundreds of millions of us around the globe tune in to watch people who eagerly endure excruciating plastic surgery; stab each other in the back for a chance to work for Donald Trump; or wolf down sea worms, cockroaches, and worse to survive on a desert island. For Generation Y, "Big Brother" is a reality television show, where, for a chance at winning half a million dollars, contestants volunteer to be cooped up in a house with total strangers and have their most private moments broadcast to a hungry audience.

It's not hard to imagine a near future of reciprocal transparency when all of us are watched and can watch right back. We're halfway there.

History's First Draft

The eyes of the world have moved to U.S. President Obama's surprising Nobel Peace Prize, but the controversies over the Physics prize just keep coming. And it's not just limited to CCD. As my colleague Sue Karlin pointed out to me in an e-mail, an Indian news site has raised questions about fiber optics.

We at Spectrum received our fair share of letters and comments about the half of the prize that went for the charge-coupled device. Our initial article "CCD Camera Chip Pioneers Share Nobel" by contributor Neil Savage led to a fruitful conversation between news editor, Sam Moore, and Michael F. Tompsett, an IEEE Fellow and one-time colleague of newly-minted Nobelists Boyle and Smith ("Nobel Controversy: Former Bell Labs Employee Says He Invented the CCD Imager") as well as a further discussion between Savage and Carlo Sequin, yet another Bell Labs CCD researcher ("Nobel Controversy: Who Deserves Credit for Inventing the CCD?").

Yesterday, published an exhaustive compendium of Nobel Prizes that arguably should have gone to Indian physicists, including:

. Jagadish Chandra Bose (wireless signaling before Marconi as well as anticipating the 'n' and 'p' type semiconductors);

. Satyendranath Bose (Bose-Einstein statistics);

. G N Ramachandran (bio-molecular structures, especially the triple helical structure of collagen); and

. E C George Sudarshan (quantum optics);

Which brings us to this week and "How India missed another Nobel Prize":

What the Academy omitted to note was that Moga, Punjab-born Narinder Singh Kapany, widely considered the Father of Fibre Optics, and, in this capacity, featured in a 1999 Fortune magazine article on the 'Unsung Heroes of the 20th Century', had far the stronger claim.
Charles Kao in a 1996 paper put forward the idea of using glass fibres for communication using light; he tirelessly evangelised it and fully deserves a share of the Prize. However, the fact remains that it was Kapany who first demonstrated successfully that light can be transmitted through bent glass fibres during his doctoral work at the Imperial College of Science in London in the early fifties, and published the findings in a paper in Nature in 1954.

The article is written by Shivanand Kanavi , who, according to his blog bio, is a theoretical physicist cum academic cum economic consultant cum business journalist. He's the author of a book, Sand to Silicon: The Amazing Story of Digital Technology, which he quotes from in making the case that Kapany deserves half of the half-prize that went for fiber optics.

Narinder Singh Kapany recounted to the author, "When I was a high school student at Dehradun in the beautiful foothills of the Himalayas, it occurred to me that light need not travel in a straight line, that it could be bent. I carried the idea to college. Actually it was not an idea but the statement of a problem. When I worked in the ordnance factory in Dehradun after my graduation, I tried using right-angled prisms to bend light.
"However, when I went to London to study at the Imperial College and started working on my thesis, my advisor, Dr Hopkins, suggested that I try glass cylinders instead of prisms. So I thought of a bundle of thin glass fibres, which could be bent easily. Initially my primary interest was to use them in medical instruments for looking inside the human body. The broad potential of optic fibres did not dawn on me till 1955. It was then that I coined the term fibre optics."

Giving credit where it is due is hard. Kanavi does a good job of tracing the idea of bending light all the way back to the 1840s. In Savage's follow-up article Carlo Sequin teases out the contributions of six different Bell Labs researchers.

If journalism is, as the journalist Phil Graham once said, the "first rough draft of history," then the Nobel committee is in the uncomfortable position in between: trying to do a journalist's job with the full weight of historical accuracy on its shoulders. And so the current controversies have a silver lining: we get to read about the contributions of the many other brilliant researchers who contributed to these marvelous ideas and life-improving technologies.

Nobel Controversy: Former Bell Labs Employee Says He Invented the CCD Imager

Who patented the first digital imager? Michael F. Tompsett says he did. (Although the signal is only digital after it’s gone through the video analog-to-digital converter chip that he also invented.)

Did Willard Boyle and George Smith invent the charge coupled device? “Their name is on the patent,” says IEEE Fellow and former Bell Labs colleague of the pair of new Nobel Prize Winners,“but all patents are a product of their time and others may have had an input.”

But did they invent “an imaging semiconductor circuit” as the Nobel citation goes? No, he says. “That was me.”

The CCD that Boyle and Smith invented was not for imaging, it was intended as a memory circuit. According to both Tompsett and the United States Patent Office, it was Tompsett who invented the imager that first demonstrated the electronic photography and video in use today. Tompsett is the sole inventor listed on United States Patent Number 4,085,456 “Charge transfer imaging devices.” The patent covers two, subtly different, types of imagers one of which is the CCD imager.

“All the imaging and reduction to practice was me,” says the physicist who in the 1970s ran Bell Labs’ CCD group, which developed TV resolution imagers.

Tompsett had been an imaging guy even before he arrived at Bell Labs. In England he invented an infrared camera tube, which was subsequently developedt, and used by the U.S. and British militaries, fire brigades and search and rescue teams, and won a Queen’s Award in Britain, he says. He also invented another silicon-imager that “never saw the light of day” because it was quickly eclipsed by the CCD. And he also came up with a solid-state thermal imager that’s now been commercialized for night vision.

But imaging isn’t his only important contribution. He also developed a technology that was key to growing the gallium arsenide layers of early LEDs and is still in use today. He invented the first solid-state MOS modem and a video analog-to-digital converter chip that is now manufactured by the millions. He now works on healthcare software as founder of Theramanager, in New Providence, N.J.

“I don’t have to hang my reputation [on the CCD imager]” he says, but “it would be nice to at least share the credit.”

You’d expect this to be a galling time for him. Even the picture he’s confronted with in newspapers and this web site is an affront: a staged photo of Boyle and Smith manipulating a camera in 1974. Neither Nobelist was involved with Bell Labs imaging chip work at the time, and Tompsett himself built the camera they are supposedly working with. He was keen to acknowledge the contributions of Ed Zimany and the rest of his group, particularly Carlo Sequin who joined Bell Labs 9 months after the invention and helped refine the imaging chips. Together, Tompsett and Sequin also wrote the first book on CCDs.

But talking to him the morning of 8 October, he seems more concerned with technical inaccuracy in an IEEE Spectrum article than his place in history. With regard to getting a Nobel Prize he says: “I hadn’t seriously thought about myself.”

“You’re not going to change [who wins] the Nobel,” he says. However, he does believe the citation should be corrected.

Image from Tompsett's CCD patent.

Post modified and updated on October 9, 2009

Nobel Controversy: Who Deserves Credit for Inventing the CCD?

Editor's Note: This is part of our ongoing coverage of the 2009 Nobel Prize in Physics. Read more about the Nobel Prize winners themselves, the Bell Labs engineer who patented the CCD imager, and the illustrious history of Bell Labs.

So who deserves the accolades for inventing the charge-coupled device? "It depends on what you're celebrating," says Carlo Sequin, who joined the team at Bell Labs developing the CCD a few months after the project began.

"My initial assumption was the Nobel in physics goes to fundamental concepts," says Sequin, now a professor of electrical engineering and computer science at the University of California, Berkeley. "If the fundamental concept was the charge transfer principle, then that goes to [Willard] Boyle and [George] Smith, and maybe Gene Gordon."

But while Boyle and Smith, who were initially trying to design something analogous to magnetic bubble memory for computers in silicon, sketched out the charge transfer concept, they were not the ones who actually built the CCD, Sequin says.

"If we try to find out who made the first practical image sensor, credit would go to Mike Tompsett, possibly [Gilbert] Amelio," he says.

The concept for the CCD was that one could build a potential well in silicon by creating a capacitor out of silicon, silicon oxide, and a metal electrode. Light striking the silicon would be absorbed and would create an electron, which would travel to the well. By applying alternating voltages, you could then moves the accumulated charges from one well to the next until they reached the edge of the chip, where the amount of the charge would reveal the intensity of the light striking each well. 

In the first design, as Sequin describes it, rows of pixels were lined up in columns, and the charges would move down the columns, from one row to the next, until they were read out in a register at the bottom. This design meant the device would take an exposure, close a shutter, move the charges down one row, and then open the shutter for the next exposure. That meant that every other frame would be spent moving the charge.

Tompsett solved the issue with the frame transfer principle. "He came up with the idea, why not double the size of that image sensor," Sequin says. Only half of the sensor would be exposed, and then the next frame of exposure would be taken while the charge was being moved. "As far as I know, he has the patent on it and he is the sole author of it, and it was his idea," Sequin says.

He says others, including himself, contributed to the development of the CCD. Amelio made the first 8 x 8 pixel chip. Sequin was heavily involved in turning that into a 128 x 128 pixel array. Walter Bertram came up with the idea of building the chip with three layers of polysilicon replacing metal as the electrodes. Since they're transparent, they could be deposited on top of the chip without blocking the incoming light. Putting them in different layers prevented them from shorting out in a way that would destroy the whole device; at most you'd lose a pixel or a column.

Sequin says two technical associates, Edward Zimany and William McNamara, were also heavily involved in developing a practical CCD. "It was six engineers who took a very fundamental principle and really made a practical thing of it." He likens Boyle and Smith to sperm donors, providing the seed of the idea, while the others were midwives and mothers who nurtured it into reality.

But the credit for the ubiquity of CCD-based cameras may belong overseas, he says. Bell Labs, which had been focused on creating a picture phone, eventually dropped the idea as impractical and stopped developing CCDs, Sequin says. Fairchild Semiconductor took up the challenge for a while, but also let it go. "Everything lay kind of dormant for another 10 years, until the Japanese picked it up," Sequin says. It took Japanese researchers at Sony and other places another five years to perfect the device. "The Americans dropped the ball," he says.


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