Tag Archives: the-institute/ieee-history

U.S. Mint Honors Game Developer Ralph Baer

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/us-mint-honors-game-developer-ralph-baer

THE INSTITUTE Gamers and coin collectors alike can now celebrate Ralph Baer’s contributions with an American Innovation dollar from the U.S. Mint. Baer, an IEEE Fellow who is considered the father of the video game, developed the Brown Box, which paved the way for modern home video game consoles including the PlayStation and Xbox.

The Brown Box offered table tennis, football, and other games. It let people play on almost any television and thus spawned the commercialization of interactive video games.

The New Hampshire American Innovation coin, which recognizes the first in-home video game console, mimics an arcade token. It depicts a Brown Box game—handball—on one side. On the other side, the words New Hampshire and Player 1 are engraved on a stamped background. The words In-home video game system and Baer’s name encircle the outside in text that is meant to pay homage to Baer’s Odyssey game.

The coin “honors a story wherein an individual, Ralph H. Baer, made a great and positive difference in our lives and that would not have happened without the time, place, and opportunity that his life in America presented,” his son Mark said in an interview with the Manchester, N.H., Ink Link. “It is good to keep that in mind, particularly in these divisive times. To be sure, we have a lot to be thankful for and a lot to celebrate.”

The mint began the American Innovation dollar coin series in 2018 to showcase innovations from particular states or territories. The series is scheduled to run through 2032.


Baer sketched out his idea for the gaming console in 1966 outside the Port Authority Bus Terminal in New York City. He brought his idea to Sanders Associates—now part of BAE Systems—a defense contractor in Nashua, N.H., where he worked. An intrigued manager gave Baer US $2,500 for materials and assigned two engineers from the company to help him develop a prototype.

The Brown Box, a soundless multiplayer system, included clear plastic overlay sheets that could be taped to the player’s TV screen to add color, playing fields, and other graphics. The console ran games off printed-circuit-board cartridges.

In 1968 the company licensed the system to television maker Magnavox, which named it the Odyssey. The company offered it in the United States in 1972 and sold 130,000 units the first year.

Baer’s 1971 patent on a “television gaming and training apparatus,” the first U.S. patent for video game technology, was based on the Brown Box.

The console was named an IEEE Milestone in 2015. Administered by the IEEE History Center, the Milestone program recognizes outstanding technical developments from around the world.

Baer’s original video games are on display in the Innovation Wing at the Smithsonian Institution, in Washington, D.C.

IEEE membership offers a wide range of benefits and opportunities for those who share a common interest in technology. If you are not already a member, consider joining IEEE and becoming part of a worldwide network of more than 400,000 students and professionals.

A Deep Dive Into IEEE’s Recent History

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/a-deep-dive-into-ieees-recent-history

THE INSTITUTE The IEEE History Center has chronicled the last 37 years of the organization and the impact it has had on electrical engineering in the 21st century. “History of IEEE Since 1984” is available on the Engineering and Technology History Wiki.

Readers can learn how IEEE transitioned to electronic publishing, its efforts to expand its membership globally, successful standard development activities, and other topics.

As digital technologies became more popular in the 1980s, IEEE worked to keep up with the shift from printed publications to digital versions, according to the document. Before the IEEE Xplore Digital Library, the organization experimented with an electronic index, launched in 1986, and CD-ROMs, which were introduced three years later. Using the index, members were able to order from their computer copies of articles published within a 12-month period. The CDs held about 200,000 documents including journal papers and conference proceedings.

Membership in IEEE also evolved during the period. Before 1989, IEEE’s membership was mostly composed of engineers from the United States. But in the 1990s, the popularity of computers and their impact on society and the strong economy fueled global expansion. Today the organization has more than 400,000 members in more than 160 countries.

The IEEE Standards Association made great strides in developing standards worldwide, according to the report. Its most well-known standard is IEEE 802.11, developed in 1997. It’s the official international standard for wireless LANs, operating at 2 megabits per second. Popular Mechanics magazine recognized the standard with its 2003 Grand Prize for Computing.

Although the document’s main focus is IEEE after 1984, its first chapter covers the merger in 1963 of the American Institute of Electrical Engineers and the Institute of Radio Engineers—which formed IEEE.

The history of IEEE previously was documented in two books that covered the organization’s first 100years. The Making of a Profession: A Century of Electrical Engineering in America was written by historian A.Michal McMahon. Engineers and Electrons: A Century of Electrical Progress was written by IEEE Fellow John D.Ryder and past IRE president Donald G.Fink. PDFs of the books are available on the Engineering and Technology History Wiki.


“History of IEEE Since 1984” is a living document. Readers with an account on the Wiki can make comments and suggest edits. IEEE History Center staff members will review the comments and, if deemed appropriate, will include them. Individual memoirs of IEEE’s history can be added in the first-hand histories section.

The project was funded by the following IEEE societies: Aerospace and Electronic Systems, Circuits and Systems, Communications, Dielectrics and Electrical Insulation, Industrial Electronics, Nuclear and Plasma Sciences, Power & Energy, Robotics and Automation, Signal Processing, Systems, Man, and Cybernetics, Ultrasonics, Ferroelectrics, and Frequency Control, and Vehicular Technology, as well as the IEEE Council on Superconductivity and Sensors Council.

IEEE membership offers a wide range of benefits and opportunities for those who share a common interest in technology. If you are not already a member, consider joining IEEE and becoming part of a worldwide network of more than 400,000 students and professionals.

How Lasers and Mirrors Proved Gravitational Waves Existed

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/how-lasers-and-mirrors-proved-gravitational-waves-existed

THE INSTITUTE In 1916 Albert Einstein predicted the existence of gravitational waves—ripples in space-time (a conceptual model of how the universe works)—in his general theory of relativity. But it wasn’t until 2015 that the Laser Interferometer Gravitational-Wave Observatory, using a specialized interferometer in observatories in Hanford, Wash., and Livingston, La., proved the waves exist. The device merges two or more sources of light to create a measurable interference pattern, according to the LIGO website

The interferometer was designed in 1972 by Rainer Weiss, a physics professor at MIT and a LIGO cofounder. LIGO worked in collaboration with the Virgo observatory in Pisa, Italy—which used a similar interferometer design. Since that first detection, LIGO and Virgo have recorded gravitational wave events generated by 10 pairs of merging black holes and two pairs of colliding neutron stars, according to the LIGO website.

On 3 February, Weiss’s interferometer design was commemorated with an IEEE Milestone in IEEE regions 5, 6, and 8. It is the first time a Milestone has been installed in three different regions. The IEEE Baton Rouge (Louisiana), Richland (Washington), and Italy sections sponsored the nomination.

Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.

“LIGO’s research on gravitational waves provided a completely new window in observing the universe,” Miriam Luizink, director of the Institutes Organization of the Dutch Research Council (NWO), said during the dedication ceremony on 3 February. “It brings deep and significant answers to the fundamental questions of space-time, our universe, its origin, and its destiny.” 

The NWO is one of the European funders of Virgo. In 2015 the Netherlands National Institute for Subatomic Physics, an NWO body, joined the European Gravitational Observatory, a private consortium that runs the Virgo interferometer.

 The virtual IEEE Milestone dedication ceremony is available on IEEE.tv.


When Weiss joined MIT in 1967 as an assistant professor of physics, the department asked him to teach an introductory course on general relativity. But he knew little about the subject, according to a 2017 article about the physicist in MIT News. When his students asked him to explain how physicist Joseph Weber supposedly detected gravitational waves using aluminum cylinders, Weiss found that he couldn’t.

Weber’s device consisted of cylinders that were 2 meters long and 1 meter in diameter, as well as several antennae. He claimed that when the device detected gravitational waves, the cylinders would vibrate. No one in the scientific community had been able to replicate Weber’s results, which have since been discredited, according to a 2020 article about Weber on the American Physical Society website.

Weiss, along with his students, designed their own machines to detect gravitational waves. His L-shaped interferometer eventually became the one that detected the waves for the first time.

His design called for a device that had two arms. Mirrors were suspended at the arm ends. When a laser was aimed down the length of the arms, it would bounce off the mirrors and back up each arm. The laser beams would take the same amount of time to arrive back where they started. Weiss’s theory was that if a gravitational wave passed through the interferometer, it should move the position of the mirrors slightly—which would change the amount of time it took for the laser beams to arrive back up the arms.

Weiss refined the design and built a 1.5-meter prototype to test his theory. He found the longer the interferometer’s arms, the more sensitive its optics were, leading him to believe his design would work if built to large enough dimensions.


It wasn’t until 1976 that Weiss’s theory started to become a reality. He teamed up with physicist Kip S. Thorne, who started his own gravitational wave experiment research group at Caltech. The two schools formed a collaboration.

Weiss, Thorn, and physicist Ronald Drever, who was a member of the team at Caltech, founded LIGO in the early 1980s. With the help of experimental physicist Barry C. Barish, the three men refined the dimensions and scientific requirements for an interferometer sensitive enough to detect a gravitational wave. Barish, who worked at LIGO as a principal investigator, was promoted to director of the project in 1994.

In the mid-1990s, LIGO received financial backing from the U.S. National Science Foundation (NSF) and erected its interferometers in Hanford and Livingston.

The interferometers—the largest ever built—had two 4-kilometer-long arms with a suspended mirror at the end of each that was 25 centimeters tall and 10 cm thick. 

In 1997, under Barish’s guidance, the LIGO Scientific Collaboration was established. It brought together international institutes and research groups to search for gravitational waves. During the IEEE Milestone dedication ceremony, Barish said that “scientific expertise is not in a single place in the world” and that LIGO “leaned heavily on international collaboration and contributions.”

The two LIGO observatories detected the first gravitational waves on 14 September 2015, at 5:51 a.m. EST. The scientists picked up a faint wobble in the observatories and confirmed that the interferometers had been microscopically stretched by “just one 10,000th the diameter of a proton,” according to the 2017 MIT News article. The distortion happened because of passing gravitational waves, which travel at the speed of light.

The signal was the first direct detection of a gravitational wave by an instrument on Earth. Virgo discovered the waves were produced by the merger of two black holes—an event that occurred 1.3 billion years ago, according to the MIT News article. 

Weiss, Thorne, and Barish received the 2017 Nobel Prize in physics for their work.

Reflecting on the achievement during the Milestone dedication ceremony, Thorne said the project helped him “understand the power of collaboration and appreciate the different skills everyone brought to the project.”

“I hope our work inspires young people to pursue science,” he said. “I think that’s one of the most important things we can do as scientists.”

IEEE Fellow Sethuraman Panchanathan, director of the NSF, said at the virtual dedication ceremony, “The strong partnerships between the LIGO facilities, academic institutions, and the states of Louisiana and Washington were central to this endeavor.”  

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation.

IEEE membership offers a wide range of benefits and opportunities for those who share a common interest in technology. If you are not already a member, consider joining IEEE and becoming part of a worldwide network of more than 400,000 students and professionals.

How IBM’s Deep Blue Beat World Champion Chess Player Garry Kasparov

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/how-ibms-deep-blue-beat-world-champion-chess-player-garry-kasparov

THE INSTITUTE Chess is making a comeback thanks to The Queen’s Gambit, a popular Netflix miniseries about a prodigy’s journey to becoming the world’s greatest player. But Beth Harmon—the fictional prodigy portrayed by Anya Taylor-Joy—never faces a supercomputer the way real-life world champion Garry Kasparov did.

IBM’s Deep Blue made history in 1997 when it became the first machine to beat a reigning world chess champion. A research team led by IEEE Senior Member Murray Campbell and Feng-hsiung Hsu developed the machine.

Kasparov accused the IBM team of cheating its way to victory. In reality, though, scientists had been interested in programming a computer to play chess since the late 1940s, according to an article on IBM’s blog about Deep Blue. It took years for engineers and computer scientists to perfect the artificial intelligence program that would one day beat a world champion.

Five decades in the making

Deep Blue’s story began in 1985, when Hsu, then a Carnegie Mellon graduate student, started working on his dissertation project: ChipTest, a chess-playing machine. Hsu worked with Campbell, who was a research associate at the university, and graduate student Thomas Anatharaman, an IEEE member, to develop ChipTest. Hsu and Campbell later joined IBM Research in Yorktown Heights, N.Y., in 1989. The duo continued developing a chess-playing machine but this time with other computer scientists working on the Deep Blue project.

The final version of the machine consisted of two 2-meter-tall towers, more than 500 processors, and 216 accelerator chips designed for computer chess, according to a paper Campbell and Hsu wrote about Deep Blue for the Artificial Intelligence journal.

The machine’s software would calculate the basic moves it could make in response to its opponent before the accelerator chips carried out more complex calculations such as assessing possible outcomes of various moves and determining the best one. The computer would decide which route to take based on the information gathered by the chips. Deep Blue could explore up to 100 million possible chess positions per second, according to the IBM article.

“Hundreds of millions of people around the world play chess,” Campbell said in a 2017 Scientific American interview. “It’s known as a game that requires strategy, foresight, logic—all sorts of qualities that make up human intelligence. So it makes sense to use chess as a measuring stick for the development of artificial intelligence.”

The team knew chess was the right game for Deep Blue to play, but the researchers had little experience with chess themselves. The team brought in grandmasters such as Joel Benjamin, who, at 13, had become the youngest-ever U.S. chess master.

The grandmasters helped the team in two ways: assisting in putting together a library of moves for the machine to access during games and playing against the machine so the team could pinpoint its weaknesses.

“Humans have been studying chess openings for centuries and developed their own favorite moves,” Campbell told Scientific American. “The grandmasters helped us choose a bunch of those to program into Deep Blue.

“Chess is an enormously complex game, and that’s why it took us, as a field, 50 years of development to finally beat the world champion.”


After the machine lost its first match in 1996 against Kasparov, the research team went back to the drawing board.

According to Campbell, the team doubled the system’s speed by developing a new chess chip—one with the enhanced ability to evaluate positions the pawns can take. The new version of Deep Blue was able to search up to 200 million options per second, depending on the pawns’ position on the board. The researchers also increased the machine’s knowledge of the game by enabling the chess chip to recognize and evaluate chess concepts including positions and lines of attack. The chips could then search through the possibilities and figure out the best move.

“Part of the improvement is we detected more patterns in a chess position and could put values on them and therefore evaluate chess positions more accurately,” Campbell said in the interview.

Deep Blue and Kasparov squared off again in 1997 in a six-game match. The grandmaster won the first game; the machine won the next one. The following three ended in a draw, and Deep Blue won the final game and thus the match.

Campbell said he and his team were “confident that the 1997 Deep Blue was much better than the 1996 version,” but they still hadn’t expected it to win.

According to IBM, the development of Deep Blue inspired researchers to create supercomputers that could tackle other complex problems such as evaluating marketplace trends and risk analysis in finance; mining data; and analyzing molecular dynamics—which helped medical researchers develop new drugs.

Deep Blue is on display at the Smithsonian Institution, in Washington, D.C., although the museum is currently closed due to the COVID-19 pandemic.

IEEE membership offers a wide range of benefits and opportunities for those who share a common interest in technology. If you are not already a member, consider joining IEEE and becoming part of a worldwide network of more than 400,000 students and professionals.

Forget Electrodes, the First EKG Machine Used Buckets of Saline Solution and Telephone Wire

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/forget-electrodes-the-first-ekg-machine-used-buckets-of-saline-solution-and-telephone-wire

THE INSTITUTE For more than 100 years, doctors have relied on electrocardiography to measure the heart’s electrical activity. The technique has its origins in the work of Willem Einthoven, who in 1905 used a string galvanometer to conduct the first recording of a human electrocardiogram (EKG). The string galvanometer, which consists of a metal fiber stretched between two magnets, was originally developed by French engineer Clément Adair in 1872 to send telegrams.

Einthoven’s EKG work has now been commemorated with an IEEE Milestone. The IEEE Benelux (Belgium) Section sponsored the nomination. Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.

“The string galvanometer offered the opportunity to record the human electrocardiogram in detail,” says IEEE Life Senior Member Wim van Etten, the section’s Milestone coordinator. “In this way the medical world received an important diagnostic tool to discover certain heart diseases.”

Due to the coronavirus pandemic, the Milestone dedication ceremony is still being planned.


Scientists began the journey to modern electrocardiography in 1873 thanks to the capillary electrometer—which was invented by Gabriel Lippmann to detect electric current. The machine consisted of metal wires and a tube with one thick end and one thin end that was filled with mercury and sulfuric acid. The tube’s thin end acted as a capillary—a narrow tube that allowed liquids to flow easily in opposition to gravity. When a pulse of electricity was sent through the machine, there were small changes in surface tension between the mercury and sulfuric acid, according to an article about the technology on the National Museum of American History website.

Using the electrometer, British physiologist Augustus Desiré Waller developed the first EKG machine in 1887. It consisted of a capillary electrometer that was affixed to a projector. Electrodes were placed on the patient’s chest and back; when electrical current entered the tube, the mercury leapt up a short distance. The movement of the mercury, which represented the heart’s electrical pulses, was projected onto a photographic plate, a flat sheet of metal on which an image was recorded.

Although Waller was able to record the patient’s heartbeat and the heart’s electric pulses, the device was not accurate or precise, and it was slow in recording the pulses. Waller also did not recognize the clinical importance of the device and technique, according to “A.D. Waller and the Electrocardiogram, 1887,” a 1987 article in The BMJ.

Einthoven, a physiology professor at Leiden University, in the Netherlands, began to analyze Waller’s data in 1901. He found errors in the visual recordings, according to a 2003 article in the Cardiac Electrophysiology Review. Einthoven wasn’t a physicist, however, and he had trouble finding a mathematical solution that would correct the errors. According to an entry in the Engineering and Technology History Wiki, he sought the help of Hendrik Lorentz, a physics professor at Leiden who won the 1902 Nobel Prize in his field. The duo was able to solve the equations and correct Waller’s measurements.

Einthoven wanted to develop a better device that could be used in clinical medicine. After three years of research and building prototypes, he introduced the string galvanometer in 1904 to the field of electrocardiography.


Einthoven’s galvanometer used a thin silver-plated quartz fiber to measure electrical signals. When the fiber carries current, putting it in a magnetic field causes it to be displaced because of the force of the magnetic field on the current, according to “Einthoven’s String Galvanometer,” a 2008 paper in the Texas Heart Institute Journal. The fiber’s movement was magnified and projected on a running film sheet, which recorded the signal. The device measured the electrical signals more precisely, more accurately, and quicker than Waller’s machine, due to the movement of the quartz fiber.

In 1905 Einthoven partnered with the Leiden University Medical Center to conduct clinical trials.

At around 272 kilograms, the machine was too heavy to be transported from Einthoven’s laboratory to the medical center. Instead, hospitalized patients were connected to the string galvanometer using a telephone wire that ran from the hospital to the laboratory, a distance of about 1.5 kilometers.

At the hospital, patients placed both arms in one bucket of saline solution and their left leg in a separate solution-filled bucket. The filled buckets acted as electrodes to conduct the current from the skin’s surface to the string galvanometer, according to the 2018 book Interpreting ECGs: A Practical Approach.

The clinical recordings enabled Einthoven to “characterize the shape of electrocardiograms as a number of successive waves,” van Etten says. Einthoven also identified and coined the terms for P,Q,R,S,T, and U waves, which are components of the basic pattern of electrical activity on an EKG. The waves represent when the heart muscles contract and relax. The names are still in use, van Etten notes.

Einthoven wanted other physicians to be able to use his machine, but because of its size, he had a tough time finding a company that would manufacture it, according to the Engineering and Technology History Wiki.

After several rejections, Einthoven simplified the design. He worked with Cambridge Scientific, in Watertown, Mass. The company mounted the machine on a table, making it easier to install in hospitals. The machine went on the market in 1905.

The EKG machine was first used in medical diagnosis in 1908, and it remains an integral part of diagnosing and monitoring heart disease.

For Einthoven’s invention and his work in electrocardiography—a term he also coined—he received the 1924 Nobel Prize in physiology or medicine.

“The string galvanometer has led countless investigators to study the functions and diseases of the heart muscle,” the Nobel website says.

The Milestone plaque is to be displayed at the Leiden University Medical Center, where the first clinical recording was taken. The plaque reads:

On 22 March 1905, the first successful clinical recording of a human electrocardiogram took place at this location, which at the time was the Academic Hospital Leiden. Willem Einthoven’s pioneering work, from 1901 to 1905, resulted in a string galvanometer specifically designed to measure and record the heart’s electrical activity, which made this medical achievement possible. This invention marked the beginning of electrocardiography as a major clinical diagnostic tool.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation.

IEEE membership offers a wide range of benefits and opportunities for those who share a common interest in technology. If you are not already a member, consider joining IEEE and becoming part of a worldwide network of more than 400,000 students and professionals.

How a Board Game and Skyscrapers Inspired the Development of the QR Code

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/how-a-board-game-and-skyscrapers-inspired-the-development-of-the-qr-code

THE INSTITUTE The use of QR (quick-response) codes has grown in recent years thanks to mobile phones, which can scan them with their built-in camera. Unlike universal product codes (UPCs), which are mechanically scanned by a narrow beam of light, a QR code “is detected by a two-dimensional digital image sensor and then digitally analyzed by a programmed processor,” says an article on Ricardo Illardo’s web design site.

QR codes are used for a variety of applications, including making contactless credit card purchases and scanning airline boarding passes. They have become even more popular during the COVID-19 pandemic. Many restaurants are displaying QR codes that allow customers to pull up the eatery’s menu on their phone, allowing them to avoid touching physical menus.

The QR code was introduced in 1994 by Japanese automotive manufacturer Denso, located in Aichi. The company developed the code to speed up its tracking of car parts.

UPCs contain a series of up to 12 numbers—which limits how much information they can store.

“The QR code can handle numbers of up to 7,087 digits,” says IEEE Member Masahiro Hara, inventor of the code. The codes also are more robust, he says: They can be read accurately even if 30 percent of the code area is soiled or damaged.

The most important feature of a QR code, Hara says, is that it can be read five times faster than a typical barcode. QR codes use short URLs, which condense information into a shorter link that loads faster, according to a post about the differences between UPCs and QR codes on the QR Code Generator blog.

The QR code is now an IEEE Milestone. The IEEE Nagoya [Japan] Section sponsored the nomination. Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.

The dedication ceremony is being planned for next year due to pandemic restrictions.


Before the QR code, Denso used UPCs to track automotive parts in its factories and warehouses, according to an entry in the Engineering and Technology History Wiki.

Because many of the boxes had several barcodes on them with different information about each part, the scanning was slowing the production and distribution process, according to an NHK World-Japan episode on QR codes.

To ease the employees’ workload, Hara, who at that time was one of the company’s engineers, set out to create a system that could store more information than the existing barcodes. The IEEE member brought together a team of Denso’s engineers and began developing a new type of code in 1992.

To fit more data into the new code, Hara took inspiration from the 2D barcodes invented in 1987 by engineer David Allais at Intermec. UPCs used only the horizontal axis to hold information, but 2D barcodes used both the vertical and horizontal axes.

Hara also was inspired by the board game Go, according to the NHK episode. In the game, pieces are placed at intersections on the board. Even if the pieces are a little off the intersection, the players still know where the pieces are. Hara applied the idea to the QR code. The pixelated parts on a QR code are doubled so that if some are damaged, others can make up for them, according to an article about common QR scanning problems on the QR Code Generator blog.

When the team began testing its new code with a UPC scanner, the device could not read code. Text surrounding the code interfered with the scanning. Hara had to find a solution, because text was necessary to identify the car parts.

He found his answer one morning while riding a train to work.

“I was just looking out the window when I noticed a tall building standing out from its surroundings,” Hara said in an interview with NHK World-Japan for the episode on QR codes. “That scene stuck with me, and I realized the code, too, needed a special symbol—something to make it stand out from the surrounding text.”

While experimenting with different frames around the code, Hara and his team tried different black-to-white ratios (the widths of the contrasting areas), trying to make one unusual enough to stand out. The team created a database of black-to-white ratios by scanning images from newspapers, then developed software that would analyze the data. After three months, Hara found the ratio of black to white needed for the QR code was 1:1:3:1:1, according to the TV show, and created a box using that ratio. The box was placed on each corner of the QR code—which allowed the scanner to successfully read it.

Denso was granted a U.S. patent in 1998, a Japanese patent in 1999, and a European patent in 2000. The QR code was given the ISO standard 18004:2015 in 2000.

“[To me] the most important thing about [the QR code] is that this technology has been adopted all over the world,” Hara told The Institute. “We are honored the QR code is now an IEEE Milestone and are very proud that the technology is utilized in various fields and that they are contributing to the development of industry.”

The Milestone plaque is to be displayed in the Denso Gallery in Aichi, Japan, an interactive exhibition hall that spotlights the company’s inventions. The plaque reads:

DENSO developed two-dimensional QR Code technology, inexpensive machine-readable optical labels that improved on barcoding by conveying larger amounts of data more quickly. Worldwide businesses soon adopted QR Codes to improve manufacturing, logistics, and management. Camera-equipped mobile phones brought QR Codes into advertising, design, and widespread applications such as electronic payments, giving consumers efficient new ways to access digital information.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

This Socialite Hated Washing Dishes So Much That She Invented the Automated Dishwasher

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/this-socialite-hated-washing-dishes-so-much-that-she-invented-the-automated-dishwasher

THE INSTITUTE The dishwasher, a popular appliance in kitchens around the world, has gone through a number of iterations throughout its 170-year history.

The first dishwasher to be granted a patent was invented in 1850 by Joel Houghton. It was a wooden box that used a hand-turned wheel to splash water on dirty dishes, and it had scrubbers. Ten years later, inventor L.A. Alexander improved on Houghton’s machine by adding a “geared mechanism that allowed the user to spin racked dishes through a tub of water,” according to an entry on reference website ThoughtCo.

But the person we have to thank for the modern-day dishwasher is Josephine Cochran (sometimes spelled Cochrane). Her machine was the first to use water pressure instead of scrubbers to clean dishes—which made it more efficient than Houghton’s or Alexander’s versions. For Cochran’s invention, she was inducted into the U.S. National Inventors Hall of Fame in 2006.

Her technical achievement is worthy of being named an IEEE Milestone, according to the IEEE History Center, but no one has proposed it yet. The Milestone program honors significant achievements in the history of electrical and electronics engineering.


Cochran’s dishwashing woes began after she married wealthy merchant William Cochran in 1858. As a socialite, she was expected to hold frequent dinner parties. She served the meals on her expensive, heirloom china. When the household staff hand-washed the dishes, the delicate china often got chipped. She opted to wash the dishes herself, but after she damaged many a plate, she decided to design and build a machine that could handle the task—faster and more carefully.

According to a profile of Cochran on the U.S. Patent and Trademark Office website, she vowed: “If nobody else is going to invent a [mechanical] dishwashing machine, I’ll do it myself.”

Although she had no technical background, she came from a family of engineers and inventors. Her father, John Garis, was a civil engineer who supervised a number of mills near the Ohio River in Illinois. Her great-grandfather John Fitch invented the first steamboat to be granted a U.S. patent.

She designed her first model in the shed behind her house in Shelbyville, Ill. Her lack of formal engineering education, however, became an obstacle, so she sought out someone who could help. Mechanic George Butters agreed to assist her in building the prototype.

To make the machine wash dishes efficiently, Cochran measured the width, height, and length of plates, cups, and saucers and constructed wire compartments for the china to sit in. The compartments separated each piece of dishware. At the bottom of the machine was a container that held soap. The compartments were placed inside a wheel that laid flat within a copper boiler, according to the Lemelson-MIT program’s profile of Cochran. A motor powered the wheel, which turned as soapy water was squirted on the dishes to clean them.

Cochran was granted a U.S. patent in 1886 for her machine, which she named the Cochran dishwasher. She advertised her invention in local newspapers and built the machines for friends and family.


To expand the market for her machine, she founded Garis-Cochran Manufacturing in the early 1890s in Shelbyville. The business was renamed Cochran’s Crescent Washing Machine Co. in 1897. It helped her connect with not only restaurants and hotels interested in buying her dishwasher but also with investors.

Many potential investors asked Cochran to resign, however, so the company could be sold to a man, according to the Patent and Trademark Office article. She refused and continued to fund the business herself.

To increase sales, Cochran displayed her machine at the 1893 Chicago World’s Fair, where she won an award for the machine’s design and durability. Thanks to that visibility, orders came pouring in and she was able to open a manufacturing facility near Chicago.

Her dishwashers became popular with the hospitality industry, but it wasn’t until the 1950s that dishwashers caught on with the public.

“Some homemakers admitted that they enjoyed washing dishes by hand, and the machines reportedly left a soapy residue on the dishes,” the Lemelson-MIT article says.

Many homes built before the 1950s used a furnace to heat water, and not all furnaces at the time could produce enough hot water to run a dishwasher.

Thanks to changing attitudes about technology and housework, though, the dishwasher’s popularity grew over time.

Cochran never saw her machines become sought-after household appliances. She died in 1913. In 1926 her company was acquired by KitchenAid, now a part of Whirlpool.

Any IEEE member can submit a milestone proposal to the IEEE History Center. The center is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

Meet Roberta Williams, The Queen of Graphic Adventure Video Games

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/meet-roberta-williams-the-queen-of-graphic-adventure-video-games

THE INSTITUTE Adventure video games have grown in popularity now that people are staying home more due to coronavirus-related restrictions, according to The Washington Post.

Such games are driven by storytelling. Players solve puzzles to move the plot along. Adventure games including Broken Age, Machinarium, and Myst are popular because they feature beautiful graphics and extensive story lines, and they test players’ critical-thinking skills.

One of the people gamers have to thank for the genre is Roberta Williams who, along with her husband, Ken, created a number of early graphic adventure games including King’s Quest, Mystery House, and Phantasmagoria.

She was honored this year with the Pioneer Award at the Game Developers Choice Awards. The award recognizes breakthrough technologies and game design milestones.

Often called “Queen of the Graphic Adventure,” Williams was not an engineer by trade. She was a stay-at-home mom who developed an interest in video games after her husband, a computer programmer at IBM, brought home an Apple II computer with the Colossal Cave Adventure game loaded on it, according to the Lemelson-MIT program’s profile of her.

She enjoyed playing the text-only game, in which the player explores a mysterious cave filled with treasure. She searched for other adventure games to play, but there weren’t many other options. That inspired her to create her own game, and she added graphics to make the experience more interesting.

“Previous games for the Apple II and other home computers were text-only, like a choose-your-own-adventure book in game form,” Smithsonian Magazine pointed out in a profile about Williams.

While Williams wrote the story line, her husband made the graphics. He used a Versawriter, a board of thick plexiglass that had an electronic stylus attached to the top, according to the Lemelson-MIT profile. There was no software at the time that could read the Versawriter, so he created a program to do that.

The couple released their first graphic adventure game in 1980, Mystery House. In the game, the player and several friends were trapped in an abandoned mansion and were being killed off one by one. The player tries to find the killer. Williams says she was inspired by the board game Clue and by the Agatha Christie story And Then There Were None, according to Laine Nooney, a video game historian.

Mystery House became a success, leading the couple to launch their video-game development company, On-Line Systems, that same year. It later was renamed Sierra On-Line. They created more than 20 titles in the 18 years they worked as game developers.

Mystery House became the first of a series of six Hi-Res Adventures. Between 1980 and 1982, the duo created Wizard and the Princess, which was the first adventure game with color graphics, and Time Zone. Wizard and the Princess sold 25,000 copies in two years, according to an article in Computer Gaming World. The game tied for fourth on the magazine’s list of 1982 top sellers.

The game that made Roberta Williams a household name, however, was King’s Quest, the first animated 3D adventure game. IBM requested that the Williamses create a game to be included in its new PCjr home computer, according to a 1984 article in PC Magazine. King’s Quest was the first in a series of eight about the adventures of the fictional royal family of Daventry.

“As a young girl, I always had enjoyed the old fairy tales of yore,” Williams said in a 2006 interview on the Adventure Classic Gaming website. “I read them and re-read them. Therefore, when thinking about designing a game, I naturally gravitated to what I liked and felt comfortable with. I felt comfortable with the idea of fairy tales, and so I put that passion into my game of King’s Quest.”

After King’s Quest, Sierra On-Line released several more games. The most well-known was the horror adventure Phantasmagoria, which was released in 1994. It was the most successful game Williams developed, selling 300,000 units during the first weekend of its release, according to an article in Business Wire. Phantasmagoria featured full motion video and live actors, but it caused controversy in the gaming community because it was for a more mature audience than the other games the company had developed.

Two years later, Sierra On-Line was sold to CUC International, and the couple retired from game development.

“The experience of creating my adventure games was—other than marrying my husband and bringing into the world my two sons—the most fulfilling, wonderful experience I could ever have had,” Williams said in the 2006 Adventure Classic Gaming interview.

Williams’ technical achievement is worthy to be proposed as an IEEE Milestone, according to the IEEE History Center. The Milestone program honors significant achievements in the history of electrical and electronics engineering.

Any IEEE member can submit a milestone proposal to the IEEE History Center. The center is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

ALOHAnet Introduced Random Access Protocols to the Computing World

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/alohanet-introduced-random-access-protocols-to-the-computing-world

THE INSTITUTE Until the 1970s, far-flung computers generally connected to one another through telephone networks. In 1968 researchers at the University of Hawaii began to investigate if radio communications could be used to link multiple computers at once.

The team introduced its Additive Links On-line Hawaii Area network, ALOHAnet, in June 1971. The network used a random access protocol, which allowed computers to transmit packets over a shared channel, as soon as they had information to send. ALOHAnet was the first use of wireless communications for a data network. Its protocol is now widely used in nearly all forms of wireless communications.

“We [the team] thought that what we were doing would be important, but I don’t think any of us thought it would be as important as it turned out to be,” IEEE Life Fellow Norman Abramson, who led the team, said in a 2009 interview about ALOHAnet in IEEE Communications Magazine. “It exceeded my wildest expectations.”

ALOHAnet is now an IEEE Milestone. Its nomination was sponsored by the IEEE Hawaii Section. Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.

The dedication ceremony, originally planned for June 2020 at the University of Hawaii at Manoa, in Honolulu, was postponed until next year due to the COVID-19 pandemic.


The University of Hawaii used ALOHAnet to connect its campuses to one another. Each campus had a small interface computer—a hub machine—that used two distinct radio frequencies: an outbound channel and an inbound channel. In order to connect, one hub machine broadcasted packets to another computer on the outbound channel, and that computer sent data packets to the first hub machine on the inbound channel.

If data was successfully received at the hub, a short acknowledgment packet was sent back. If an acknowledgment was not received by the computer, it would automatically retransmit the data packet after waiting for a randomly selected amount of time. The mechanism detected and corrected collisions that were created when the machine and the computer attempted to send a packet at the same time, according to the Engineering and Technology History Wiki entry about the Milestone.

Computer networks were not well understood at the time, and it took several years for the researchers to perfect their design.

“In a sense, [the acknowledgement mechanism is] an obvious thing to do,” Abramson said in the article. “But when you start off on this kind of research project, some of the obvious things don’t appear as obvious as they do a little later.”

ALOHAnet was connected to ARPANET via satellite in December 1972 under the guidance of the U.S. Defense Advanced Research Projects Agency. The connection allowed for reliable computer communications throughout the United States, according to the Wiki entry.

ALOHAnet used a VHF transponder in 1973 to connect to an experimental NASA satellite in order to demonstrate PacNet, an international satellite data network. The demonstration connected the NASA facility in California with five universities in Australia, Japan, and the United States, the Wiki entry says.

The Milestone plaque is to be displayed at the entrance of Holmes Hall at the University of Hawaii at Manoa, which was where the technology was developed, tested, and demonstrated. The plaque reads:

In June 1971 the ALOHA packet radio data network began providing inter-island access to computing facilities at the University of Hawaii. ALOHAnet was the first to demonstrate that communication channels could be effectively and efficiently shared on a large scale using simple random access protocols. It led directly to the development of Ethernet and personal wireless communication technologies.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

Learn the History of GPS From Its Founders

Post Syndicated from Karen Kaufman original https://spectrum.ieee.org/the-institute/ieee-history/learn-the-history-of-gps-from-its-founders

THE INSTITUTE The IEEE History Center’s Engineering and Technology History Wiki now contains oral histories from all four fathers of GPS, thanks to Richard and Nancy Gowen’s generous gift to the IEEE Foundation’s IEEE History Center Fund. Richard Gowen, an IEEE Life Fellow, served as the 1984 IEEE president and is president emeritus of the IEEE Foundation. The IEEE History Center in 1999 had interviewed GPS founder Brad Parkinson.

The Gowens’ gift enables the center to complete its GPS collection with oral histories from the three other principal architects—James Spilker, Richard Schwartz, and Hugo Fruehauf.

Oral histories provide spoken commentaries through recorded interviews and represent a primary source of raw data that contributes to historical narratives.

“They capture memories of those who participated in historical events that might not otherwise be represented in other forms of historical documents,” says Michael Geselowitz, senior director of the IEEE History Center.

Parkinson was a colonel in the U.S. Air Force and in 1972 was appointed the program manager of Project 621B, which developed, built, and launched the first GPS satellites. He received the 2018 IEEE Medal of Honor for his role in the invention of the technology.

Spilker was a cofounder of Stanford Telecommunications, in Sunnyvale, Calif., and executive chairman of AOSense, also in Sunnyvale. Spilker received the 2015 IEEE Edison Medal “for contributions to the technology and implementation of civilian GPS navigation systems.” He died in 2019.

Schwartz was the GPS satellite program manager at Rockwell and part of Parkinson’s team. Freuhauf also worked for Rockwell and was a key member of the company’s Apollo program and chief engineer for the design and development of the GPS satellite from 1973 to 1978.

Based on their “groundbreaking engineering innovation, which is of global benefit to humanity,” Freuhauf, Parkinson, Schwartz, and Spilker received the 2019 Queen Elizabeth Prize for Engineering.

The Gowens say they are proud to help the IEEE Foundation capture the important testimonies for posterity.

“Congratulations to the four gentlemen on the completion of their oral histories within the IEEE History Center’s GPS Collection,” Richard Gowen says. “We thank you for your vision and tenacity in enabling the ability to locate a position on the globe with pinpoint accuracy and then to travel to another position. Nancy and I are pleased to have had the opportunity to sponsor the recognition of these four gentlemen for their leadership in providing the global positioning satellite system.”

The IEEE History Center boasts more than 800 oral histories and over 20 collections including Women in Computing, Queen Elizabeth Prize for Engineering Recipients, and Human Space Travel.

The History Center relies on donor support to preserve, research, and promote the legacy of electrical engineering and computing. It benefits from donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

Karen Kaufman is senior manager of communications for the IEEE Foundation.

Budapest’s Electric Underground Railway Is Still Running After More Than 120 Years

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/budapests-electric-underground-railway-is-still-running-after-more-than-120-years

THE INSTITUTE As Budapest’s population grew in the late 1800s, the streets were becoming congested with horse-pulled and electric tramways. The city’s leaders began looking for a convenient way for people to travel across the city that would alleviate congestion on the roads. Their solution was to construct a public transportation system underground.

It took a little less than two years to build an electric underground railway: the Budapest Metro Line No. 1 system. The first such railway in continental Europe, it began operating in 1896.

The tunnel it used was constructed using modern tools such as electric cement mixers and excavators.

Among the railway’s innovative elements were bidirectional tram cars; electric lighting in the subway stations and tram cars; and an overhead wire structure instead of a third-rail system for power.

The Budapest line, still in use today more than 120 years after its inauguration, is now an IEEE Milestone.

Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world. The IEEE Hungary Section was the sponsor.

“The railway system influenced the construction and design of subways in Boston, Buenos Aires, Paris, and other cities around the globe,” says IEEE Senior Member Peter Kadar, the section’s Milestone coordinator.

The dedication ceremony, originally planned for 25 March at the Budapest Underground Railway Museum, was postponed indefinitely due to the COVID-19 pandemic.


The metro line runs underneath Andrassy Avenue, which connects the city center—Vorosmarty Square—to City Park. Back in the 1890s, the avenue allowed only pedestrian traffic, so city leaders decided that would be an ideal location to start construction, which began in 1894.

The main sewerage canal that ran underneath the avenue presented a challenge, Kadar says: It limited how tall the tunnel could be. Workers had to use the “cut and cover” approach to build the structure. They dug a shallow trench and constructed the tunnel inside it. The street was rebuilt over the tunnel once the structure was complete. It was the first time the “cut and cover” technique was used to create a tunnel under a main road, Kadar says.

Concrete reinforced with iron sheets was used instead of bricks to build the tunnel because it was lightweight, strong, and had a long lifespan, according to the Engineering and Technology History Wiki entry about the Milestone. The ferroconcrete also was used to build ticket booths, station platforms, and entrances for 11 metro stations along the 4-kilometer route.

It took 2,000 construction workers working double shifts to complete the project, which took only 21 months.


Although it was not the first underground train system, the Budapest Metro Line was the precursor to today’s subways. It was the first underground railway to use bidirectional tram cars—cabins on either end of the train, each with their own driver. Other underground trains at the time used locomotives with a single driver, who operated a crossover switch to shift the train to another track. That limited where the train could switch direction. The bidirectional carriages, however, gave drivers the ability to reverse direction when necessary, allowing more flexibility.

Existing tram cars were modified to accommodate the tunnel’s height constraints. Standard railway vehicles at the time were too tall for the 3-meter tunnel. Each tram car had two chassis that supported the vehicle and provided it with traction and braking but made the cars too large for the tunnel. To lower the cars’ height, the engineers built a low-floor chassis. It had fixed wheels attached to a small axle base as well as a motor and brake discs. Each carriage was connected by a goosenecked chassis, which used a ball and coupler.

The Budapest line was the world’s first low-floor tram, Kadar says.

To power the railway system, engineers installed overhead lines instead of laying a conventional third-rail system along the tracks. The trains used electric current collectors to connect with the overhead wires.

A power station was built on Akacfa Street, about five blocks south of Andrassy Avenue, where a 350-volt DC current was generated for the railway. The current powered the tram system as well as the lights in the cars and stations. Budapest was the first city in the world to use the electric current collector system underground.

The Milestone plaque will be displayed at the entrance of the first station, which is the site of the Budapest Underground Railway Museum. The plaque reads:

In 1896 Budapest Metro Line No. 1 was inaugurated, the first underground railway designed specifically to use electric power, rather than adapted from steam-powered systems. It offered several innovative elements including bidirectional motor carriages, the “gooseneck chassis,” and electric lighting in the stations and carriages. This line’s design influenced later subway construction in Boston, Paris, Berlin, and other metropolitan areas worldwide.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

Founder of Italy’s Pavia Museum of Electrical Technology Works to Keep Engineering History Alive

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/founder-of-italys-pavia-museum-of-electrical-technology-works-to-keep-engineering-history-alive

THE INSTITUTE Although not a trained historian, IEEE Senior Member Antonio Savini says he has always been interested in the origins and evolution of technology. It’s important not only to preserve electrical technology and artifacts, he says, but also to explain their impact on society.

“If engineers do not understand the evolution of technology,” Savini says, “they lack important knowledge that could be applied to their own innovations.”

He became a member of the IEEE History Committee in 2012, and he still serves on it today.

While working as an engineering professor at the University of Pavia, in Italy, he helped establish the university’s Research Center for the History of Electrical Technology in 1998. The center promotes exhibitions, meetings, and lectures and conducts research.

In 1999, Savia was tasked with leading the effort to conceptualize and design the university’s Museum of Electrical Technology. Savini was the museum’s director until he retired in 2015, but he’s still involved.

“The intent of the museum was to preserve the memory of important steps in the evolution of electrical technology,” he says.

The oldest artifacts on display are from the early 1800s.


Since 1980, the University of Pavia has been collecting old and new electrical equipment to teach its students about how machines work. Most artifacts were industrial equipment, such as large power generators, high-voltage insulators, and a tramway, Savini says. The university wanted to build a museum to showcase its collection, but it didn’t think it had enough variety, he says.

According to an article in the IEEE Xplore Digital Library about the museum’s establishment and its efforts to build its collection, two major Italian organizations stepped up to help. Energy company ENEL and telecommunications company SIRTI each had museums of their own but were looking for one central place to house all their technology-related exhibits, so they offered their collections to the university. That decision spurred the construction of the Pavia Museum.

The University of Pavia’s electrical engineering department uses the museum’s artifacts as teaching aids.

One of the artifacts from SIRTI collection was a German enciphering machine used in World War II, an Enigma, Savini says.

The museum opened its doors to the general public in 2007. During the first year the museum was open, it attracted more than 4,000 visitors, including student field trips. Since that initial year, it has continued to add exhibits and events.


When Savini began curating the museum, he asked a team of experts to help him. They included representatives from European science and technology museums.

To show visitors the evolution of electrical technology, the museum has five exhibition areas: Early Electricity (up to around 1880), Electricity Comes of Age (around the end of the 19th century), Electricity for Everyone (early 20th century), Electricity Everywhere (later 20th century), and Electricity Today and in the Future.

Today’s technology museums are competing with TV programs and websites that cover the history of tech. “Museums—where wonderful objects such as a replica of Volta’s electric battery, Thomas Edison’s DC generator, and a German Enigma machine are preserved in a silent and isolated environment—are struggling to attract enough people,” Savini says.

To modernize, the museum has incorporated touch screens that describe each artifact’s importance and impact on society.


Savini’s goal for the museum was not only to showcase the history of technology but also to promote the relationship between science and art through exhibits and partnerships with other universities and museums.

People’s knowledge about the connection between art and science is fragmented because of how both are viewed in modern times, he says.

“Both engineers and artists work on the basis of curiosity and creativity,” he says. In the past, he notes, there were instances when innovators, like Leonardo da Vinci, were engineers as well as artists, and vice versa.

Savini says that one of the most memorable experiences he has had in trying to bridge the gap between engineering and art was in 2016, when a group of students from the Milan Academy of Art visited the museum. While giving them a tour, Savini says, they were particularly fascinated by an exhibit on the history of electricity.

“They thought of electricity as something mysterious and wanted to know more about how it worked,” he says. That experience led him to lecture at the art school about electricity. It also spurred him to start a project in which the academy’s students were asked to prepare artworks for the museum incorporating electricity or inspired by it. The museum displayed the installations, paintings, and sculptures for a couple of months.

“In the future,” Savini says, “we want to exhibit pieces of art from famous artists who have been inspired by electrical technology.”

This 40-Year-Old Transistor Changed the Communications Industry

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/this-40yearold-transistor-changed-the-communications-industry

THE INSTITUTEWhile working as an electronics engineer in 1977 at Fujitsu Laboratories in Atsugi, Japan, IEEE Life Fellow Takashi Mimura began researching how to make the metal-oxide-semiconductor field-effect transistor quicker. The MOSFET, which had been invented in 1966, was the fastest transistor available at the time, but Mimura and other engineers wanted to make it even quicker by enhancing electron mobility—how speedily electrons could move through semiconducting material.

Mimura began to research an alternative semiconductor to the silicon used in the MOSFET, hoping it would be the solution. He came across an article in the Applied Physics Letters journal on heterojunction superlatticesstructures of two or more semiconductors of significantly different bandgaps—developed by Bell Labs in Holmdel, N.J. The superlattices, which used a modulation-doping technique to spatially separate conduction electrons and their parent donor impurity atoms, inspired Mimura to create a new transistor.

In 1979 he invented the high-electron-mobility transistor. His HEMT used a heterojunction superlattice to enhance electron mobility, improving on speed and performance.

The invention now powers cellphones, satellite television receivers, and radar equipment.

The HEMT was dedicated an IEEE Milestone on 18 December. The IEEE Tokyo Section sponsored the Milestone. Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.


The HEMT consists of thin layers of semiconductors—n-type gallium arsenide and aluminum gallium arsenide—as well as a heterojunction superlattice; a self-aligned, ion-implanted structure; and a recess gate structure. The superlattice, which acts as a diode, forms between the layers of n-type gallium arsenide (a highly doped narrow bandgap) and aluminum gallium arsenide (a nondoped narrow bandgap). Using different bandgap materials causes a quantum well to form in the superlattice. The well lets electrons move quickly without colliding with impurities.

 The self-aligned, ion-implanted structure consists of a drain, a gate, and a source, which sit on top of a second layer of n-type gallium arsenide—the recess-gate structure. Electrons originate from the source and flow through the semiconductors and heterojunction superlattice into the drain. The gate controls the current flow between the drain and the source.

According to a paper in IEEE Transactions on Electron Devices, the recess-gate structure decreases the chance of a current collapse—a reduction of current after high voltage is applied. A current collapse would decrease the transistor’s response at high frequencies.

The Milestone plaque, displayed in the exhibition room on the ground floor of Fujitsu Laboratories in Atsugi reads:

The HEMT was the first transistor to incorporate an interface between two semiconductor materials with different energy gaps. HEMTs proved superior to previous transistor technologies because of their high-mobility channel carriers, resulting in high-speed and high-frequency performance. They have been widely used in radio telescopes, satellite broadcasting receivers, and cellular base stations, becoming a fundamental technology supporting the information and communication society.

 This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

Modern Civilization Relies on This Crystal-Growing Method

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/modern-civilization-relies-on-this-crystalgrowing-method

THE INSTITUTELaptop computers, mobile phones, and a host of other electronic devices wouldn’t exist without semiconductors such as monocrystalline silicon.

Early methods of producing semiconductors were unpredictable and unreliable. There was no way for scientists at the time to prevent the semiconductors from being contaminated by impurities in the air. In 1916, however, Polish chemist Jan Czochralski invented a way to grow single crystals of semiconductors, metals, and synthetic gemstones. The process—known as the Czochralski method—allows scientists to have more control over a semiconductor’s quality and is still used today.

Czochralski discovered the method by accident while working in a laboratory at Allgemeine Elektrizitäts-Gesellschaft (AEG), an electrical-equipment company in Berlin. According to JanCzochralski.com, while investigating the crystallization rates of metal, Czochralski dipped his pen into molten tin instead of an inkwell. That caused a tin filament to form on the pen’s tip. Through further research, he was able to prove that the filament was a single crystal. His discovery prompted him to experiment with the bulk production of single crystals of semiconductors.

The Czochralski process of growing single crystals was dedicated as an IEEE Milestone on 14 November during a ceremony held at the Warsaw University of Technology. The IEEE Poland Section and the IEEE Germany Section sponsored the Milestone. Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.


Czochraslski used a silica crucible—a container made of quartz—to grow the crystals. He sat it inside a chamber that was free from oxygen, carbon dioxide, and other potential contaminants. The chamber was surrounded by heaters that converted electric energy into heat. He also used radio waves at a high frequency to melt silica inside the crucible. When the temperature inside the crucible reached about 1,700 kelvins, it melted the high-purity semiconductor-grade silica.

Once the silica melted, he placed a small piece of polycrystalline material—a seed crystal—on the end of a 14-centimeter-long, rotating rod. He then slowly lowered the rod into the crucible until the seed crystal dipped just below the surface of the molten silica. He found that a trace of impurity elements—a dopant—such as boron or phosphorus, could be added to the molten silica in precise amounts to change the silica’s carrier concentration. Depending on what dopants he added, the silica turned into p-type or n-type silicon. They have different electronic properties. When they are put together, they create a diode, which allows for current to flow through the silicon.

Czochraslski simultaneously lifted and rotated the rod that held the seed crystal. During this step, the molten silicon crystallized at the interface of the seed. That formed a new crystal.

The shape of the new crystal, particularly the diameter, can be controlled by adjusting the rod’s heating power, pulling rate, and rotation rate, according to the Encyclopedia of Materials: Science and Technology. That “necking procedure” technique is crucial for limiting the crystal’s structural defects.

Other semiconductors, such as gallium arsenide, also can be grown using the Czochralski method.

The Milestone plaque, mounted at the entrance to the Warsaw University of Technology’s main hall, reads:

In 1916, Jan Czochralski invented a method of crystal growth used to obtain single crystals of semiconductors, metals, salts, and synthetic gemstones during his work at AEG in Berlin, Germany. He developed the process further at the Warsaw University of Technology, Poland. The Czochralski process enabled development of electronic semiconductor devices and modern electronics.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

How the Telemobiloskop Paved the Way for Modern Radar Systems

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/how-the-telemobiloskop-paved-the-way-for-modern-radar-systems

THE INSTITUTEA device invented more than 100 years ago to prevent ships from running into each other in inclement weather was the forerunner to today’s radar systems.

On the morning of 17 May 1904, electrical engineer Christian Hülsmeyer carried out the first demonstration of radar using radio reflections at the Dom Hotel in Cologne, Germany. Using the Telemobiloskop he invented, Hülsmeyer was able to detect the metal gate that led to the hotel’s courtyard through a curtain he had hung in front of the gate. He did that to prove to spectators that his device could detect a target through a physical barrier. Next, he used the device from the banks of the nearby Rhine River to detect a barge approaching the Hohenzollern Bridge from a distance of several hundred meters.

The invention was dedicated as an IEEE Milestone on 19 October in a ceremony held at the Dom Hotel. The IEEE Germany Section sponsored the Milestone. Administered by the IEEE History Center and supported by donors, the Milestone program recognizes outstanding technical developments around the world.

“Radar technology is omnipresent today and has become an important part of many systems in our society,” Milestone coordinator Peter Knott, an IEEE senior member, told The Institute. “We are very pleased that with this Milestone, Christian Hülsmeyer, an important pioneer in this field, has gained recognition.”


When Hülsmeyer was a boy, he witnessed a boating accident on the Rhine as two ships collided on a foggy night. Several passengers were killed. The incident inspired him to search for a way to prevent tragedies that result from poor visibility, according to the Engineering and Technology History Wiki entry about the Milestone.

Hülsmeyer pursued a teaching degree at the Lehrerseminar, a teacher’s college, in Bremen. He experimented with electromagnetic waves in the school’s labs—which inspired him to become an electrical engineer. He joined the electrical engineering company Siemens & Halske, also in Bremen, as a trainee.

In the Telemobiloskop’s patent application, which was granted in 1906, Hülsmeyer described his invention: “Hertzian-wave projecting and receiving apparatus adapted to indicate or give warning of the presence of a metallic body, such as a ship or train, in the line of projecting of such waves.”

The Telemobiloskop was composed of a large wooden box, a spark-gap transmitter, two simple parabolic antennas, and a crude detector. It also had an electric bell to indicate the presence of its target. The antennae sat on a movable platform on top of the box and could rotate 360 degrees.

The transmitter generated radio-frequency electromagnetic waves using an electric spark. Transmitted signals were directed by a single-edge opened metal case—a projector screen, according to a speech IEEE Fellow Joachim Ender made about the Telemobiloskop at the 2002 European Conference on Synthetic Aperture Radar <is there a URL for the conference?>.

The signals the Telemobiloskop received were transferred to the detector, which was housed in the box’s bottom. When a reflected signal reached the receiver, the relay was activated and the bell would ring to indicate that an object had been detected. When it moved out of range, the bell stopped ringing.

To help determine the object’s location, Hülsmeyer also invented an electromagnetically driven toothed-wheel mechanism—which he called Kompass—that had a pointer rotating in a synchronous manner to the antenna. It allowed Hülsmeyer to know the direction of the target by following the pointer.

The Milestone plaque, mounted on the Hohenzollern Bridge over the Rhine, reads:

On 17 May 1904, near this site, Christian Hülsmeyer demonstrated his Telemobiloskop: a spark gap transmitter, simple parabolic antennas, detector, and an indicator. It was designed to ring a bell when a barge passed the system at a range of several hundred meters. He patented this device in Germany, the United Kingdom, and the U.S.A. This was the world’s first operable device to detect radio reflections, a predecessor of radar.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.

Pipe-Protecting Technology Invented by Raychem Is the 200th IEEE Milestone

Post Syndicated from Joanna Goodrich original https://spectrum.ieee.org/the-institute/ieee-history/pipeprotecting-technology-invented-by-raychem-is-the-200th-ieee-milestone

THE INSTITUTEWhen frozen pipes burst, they can cause extensive flooding damage, leading to costly repairs.

In 1972 Raychem, now part of nVent Thermal, began manufacturing a cable it invented that automatically adjusted the temperature around pipes based on their surface temperature.

The invention maintained a temperature, set by a thermostat, for as long as the cable was turned on. Today electric self-regulating trace heaters handle the vast majority of trace heating.

The device also helps to conserve energy, increases accuracy of the temperature maintained, and allows the temperature to be constantly monitored.

The electric self-regulating polymer trace heater was dedicated as an IEEE Milestone on 28 August at the nVent Thermal factory in Redwood City, Calif., where the cables first were manufactured. It became the 200th IEEE Milestone to be designated. The IEEE Santa Clara Valley (California) Section sponsored the Milestone.

“The Milestone commemorates the invention of a heating system that has a semi-infinite parallel array of resistances that continuously vary with the local ambient temperature,” IEEE Fellow Chet Sandberg told The Institute. “This technology is used in many commercial, consumer, and industrial applications today.”


The cable is housed in a plastic shell. Inside is a metal braid, plastic insulation, and a conductive core. The outer shell shields the cable against moisture, and the metal braiding removes excess electrical charge in the cable. The heart of the heater consists of parallel bus wires connected by a polymer matrix embedded with a conductive carbon black material such as coal tar. When the polymer warms, it expands, which separates the carbon paths and causes the resistance to increase. When it cools, the matrix contracts, lowering the resistance and allowing more current to flow through the device to create heat.

According to the Engineering and Technology History Wiki entry about the Milestone, the invention’s key electrical achievement was the development of a polymer matrix that returns to its original state when cooled. The process is able to repeat because the polymer is treated with radiation in order to crosslink it, creating a material with a structure that can rebound after expansion.

A plaque honoring the trace heater was mounted in the lobby of the nVent Thermal factory. It reads:

In 1972 Raychem Corp. patented and began producing the first commercially successful electric self-regulating heat-tracing cable. The conductive polymer in this cable revolutionized the temperature maintenance of process piping, which has had major applications in refineries and chemical plants, and made freeze protection of water pipes simple and energy-efficient. By 2008, the firm had manufactured and sold 1 billion feet of this cable.

This article was written with assistance from the IEEE History Center, which is funded by donations to the IEEE Foundation’s Realize the Full Potential of IEEE campaign.