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Nobel Shocker: RCA Had the First Blue LED in 1972

The work of this year’s winners of the Nobel Prize in Physics cannot be understated. As the Nobel Foundation said when they awarded the prize to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura—the three inventors for the blue light-emitting diode—“Incandescent light bulbs lit the 20th century; the 21st century will be lit by LED lamps.”

But there’s more to this story. “The background is kind of being swept under the rug,” says Benjamin Gross, a research fellow at the Chemical Heritage Foundation in Philadelphia. “All three of these gentlemen deserve their prize, but there is a prehistory to the LED.” In fact, almost two decades before the Japanese scientists had finished the work that would lead to their Nobel Prize, a young twenty-something materials researcher at RCA named Herbert Paul Maruska had already turned on an LED that glowed blue.

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Chemistry Nobel Honors Microscopes Made to See the Nanoworld

Three scientists were awarded this year’s Nobel Prize in Chemistry for developing a new generation of optical microscopes that can peer at the processes inside living cells on the nanoscale. Their invention represents a huge leap over the optical microscopes that gave scientists their first glimpse of tiny living organisms starting in the 17th century.

The biological imaging techniques pioneered by Eric Betzig, Stefan Hell, and William Moerner succeeded in overcoming a physical limit defined by half the wavelength of light and first described by microscopist Ernst Abbe in 1873. That limit meant optical microscopy could not reveal biological objects smaller than 0.2 micrometers, such as viruses or proteins. Modern electron microscopes have the resolution to see at such small levels of detail, but their preparation is lethal for cells under observation and prevents scientists from peering at the inner workings of living cells.

Chemistry Nobel Laureates 2014

One of the first breakthroughs came from Stefan Hell, a physicist at the Max Planck Institute for Biophysical Chemistry, in Göttingen, Germany. In 1993, Hell had his eureka moment while working on fluorescence microscopy, a technique that involved using pulses of light to excite certain molecules in a way that allows scientists to see their glowing locations within cells. The problem was that the microscope resolutions were still too low to see objects such as individual DNA strands.

Hell bypassed the limitation by proposing a method called stimulated emission depletion. After using a laser beam’s pulse of light to excite the fluorescent molecule, a second laser quenches the fluorescent glow except for a nanometer-size volume in the middle. That allows scientists to build a very detailed image of the molecule by sweeping the “nano-flashlight” along the object and continuously measuring light levels, according to a Nobel Foundation explainer. Those small volume images were put together to form a detailed whole image.

By comparison, Eric Betzig and William Moerner, working independently, helped develop a second method called single-molecule microscopy. That method takes several images of the same area while turning the fluorescence of a few individual molecules on and off. Once all the images are superimposed on one another, they form a single “super-image” with details at the nanoscale level.

In 1989, Moerner, a chemist at Stanford University and an IEEE Senior Member, became the first scientist to ever measure the light absorption of a single molecule (he worked at the IBM research center in San Jose, Calif., at the time). He followed up that work eight years later by showing it was possible to control the fluorescence of single molecules, work he described in the journal Nature in 1997.

Such control over single-molecule fluorescence represented the practical solution to a theoretical concept envisioned by Eric Betzig two years earlier. Betzig, a physical chemist at the Janelia Research Campus of the Howard Hughes Medical Institute in Ashburn, Va., developed his ideas in the 1990s while working on a new type of optical microscopy called near-field microscopy.

After leaving his research career for a while (to work at his father’s machine tool company), Betzig returned and eventually demonstrated how the single-molecule fluorescence could help create the highly detailed “super-image” of a specialized cell organelle called a lysosome. His groundbreaking work appeared in the journal Science in 2006.

These advances in optical microscopy have allowed researchers to begin studying the inner workings of living cells in unprecedented detail. Hell has used the technique to peer inside living nerve cells to understand how brain synapses work. Moerner has examined proteins related to Huntington’s disease, an inherited genetic disorder that leads to the malfunction and breakdown of brain cells. Betzig has studied cell division within embryos.

All three researchers have published much of their work in IEEE journals such as IEEE Photonics Journal and through the IEEE Engineering in Medicine & Biology Society.

No Nobel for the Father of the LED

Given the Nobel Foundation’s statutes (three people at maximum, no posthumous awards), it’s almost inevitable that every year, there will be people who deserve a share of a Nobel Prize that are left out. 

Nick Holonyak Jr., the person widely credited with the development of the first visible-light LED, the device that now lights up countless clocks, traffic signals, and other electronic displays, might be one of them. On Tuesday, the Royal Swedish Academy of Sciences awarded this year’s Nobel Prize in Physics to three inventors of the blue light-emitting diode. Holonyak isn’t exactly complaining that he isn’t among them; his objection is that his 1962 invention has never been singled out for recognition by the academy. 

“Hell, I'm an old guy now,” Holonyak said in an interview with the Associated Press. “But I find this one insulting.”

In announcing the prize yesterday, the Nobel Foundation highlighted the great potential social impact of blue LEDs, which made LED bulbs possible and could help dramatically reduce the amount of energy the world expends on lighting.

But some of Holonyak’s colleagues are puzzled at the selection. “I can’t help but wonder why the committee chose to single out the blue light LED in their selection of the winners,” Andreas Cangellaris, dean of engineering at the University of Illinois, Holonyak’s home for many decades, told a reporter at The News-Gazette, a local newspaper. “Very puzzling and very disappointing.”

The story of the LED, of course, goes back further than and well beyond Holoynak. Before Holonyak’s red LED, there was the infrared LED (along with even earlier discoveries), and there is a host of other researchers who could share credit in the device’s development.

Indeed, The News-Gazette went on to say that Holonyak “was disappointed and irritated at the omission—not just for himself, but for many of his former students and colleagues who did groundbreaking work themselves.” 

Holonyak, who won the IEEE Medal of Honor in 2003, originally set out to develop a red diode laser. In the process, he also succeeded in creating a red LED. Holonyak and several of his colleagues later went on to use compound semiconductors similar to those used to create the first LED to develop a transistor laser, a device capable of emitting both electrical and optical signals. 

You can read more about his seminal work in an IEEE Spectrum profile here. Holonyak also made a couple of nice appearances online on the 50th anniversary of his invention: an audio slide show for the BBC and an excellent video interview for General Electric, where the device was made. 

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Plasmon Laser Is Fastest to Switch

Those laying the foundations for future generations of electronics have long had a fondness for photons. But until recently, there was a catch: photons would limit the miniaturization now achieved with silicon chips because they need space—at least half their wavelength—to move around. So structures on photonic chips would have to be at least a few hundred nanometers wide.

But this catch now comes with its own caveat: Researchers expect that dealing with plasmons (electron waves on a metal surface generated by light) instead of photons themselves will allow the creation of photonic chips with structures comparable in size to those on the most advanced silicon chips. Indeed, new plasmonic nanolasers that can focus light in spots much smaller than their wavelength might play a key role in future photonic circuits.

Plasmonic lasers aren’t just important because of their size; they’re also amazingly fast. Their speed was the big news reported by researchers at Imperial College London and the University of Jena in Germany last week in Nature Physics. They’ve created an ultrafast plasmonic semiconductor laser that will ultimately be able to switch its power on and and off a thousand billion times per second. This new terahertz laser is a thousand times as fast as today’s speediest lasers.

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Inventors of Blue LED Win Nobel Prize in Physics

Taking a more practical turn, the Royal Swedish Academy of Sciences has awarded this year’s Nobel Prize in Physics to three inventors of the blue light-emitting diode.

Isamu Akasaki and Hiroshi Amano, who worked together at the University of Nagoya, and Shuji Nakamura, who worked at Nichia Chemicals in Tokushima, developed bright versions of the devices in the late 1980s and early 1990s. 

“Their inventions were revolutionary,” the Nobel Foundation said in a press release. “Incandescent light bulbs lit the 20th century; the 21st century will be lit by LED lamps.”

LEDs can produce as much as 300 lumens per watt of electrical input power, the press release goes on to note, nearly 20 times as much as incandescent bulbs yield and about four times as much as that of fluorescent lamps. The greater efficiency could help conserve resources in a world where about a quarter of the energy produced goes into lighting.

In incandescent bulbs, light is almost an afterthought; the filaments are essentially just big resistors and most of the energy is released in the form of heat. 

LEDs more directly convert electricity into photons. They typically contain two layers of semiconducting materials, one engineered to contain an excess of electrons and the other an excess of holes (absences of electrons that act as positive charges). To make photons, the electrons from one side and holes from the other are drawn together. They meet at a thin, active layer between the two materials, where they join and release energy in the form of photons. 

Nakamura often takes the headlines in discussions of the invention of the blue LED. But, the Nobel Foundation notes, Akasaki and Amano were the first to develop the high-quality gallium nitride used to make the blue diodes, beginning in 1986 (pdf). The three lighting luminaries, all of whom are IEEE members (Akasaki is a Life Fellow), have won multiple IEEE awards including the IEEE Edison Medal and numerous IEEE Photonics Society Awards.  

With the invention of these devices, engineers could now create white light by using blue light to excite a phosphor or by combining red, green, and blue devices. LEDs now light LCD screens, are slowly pushing aside incandescent and fluorescent lighting in homes and offices, and can be used to electronically control color to better mimic the diurnal cycle. The blue LED also formed the basis for a later invention – the blue semiconductor laser.

Development on the blue LED has continued steadily since its invention. One key challenge has been LED droop, a drop in efficiency when currents are raised to produce more light. Last year, a team of researchers claimed they’d found the source of the droop, but others weren't so confident. And engineering a way to circumvent it is another matter.

Photos: Jonathan Nackstrand/AFP/Getty Images

The Internet of Things Gets a New OS

British processor powerhouse ARM Holdings, said last week that it intends to launch a new, low-power operating system that will manage web-connected devices and appliances using chips based on the company’s 32-bit Cortex-M microcontrollers. 

The operating system, called mbed OS, is meant to resolve productivity problems that arise from fragmentation—where different devices in the so-called “Internet of things” (IoT) market run on a hodgepodge of different protocols. ARM is looking to consolidate those devices under a single software layer that's simple, secure, and free for all manufacturers to use.

“Instead of having large teams spending years designing a product,” ARM vice president of research and development Kriztian Flautner told the BBC, “we'd like to turn that into months, so that you can take the [hardware] components, assemble the right ones, connect the device and focus on the problem you are solving and not the means to getting there."

In the last few years, ARM has made a push to develop more technologies designed for IoT products. In a Pew survey this past spring, 83 percent of respondents thought the future of IoT would help improve their lives. Gartner, a tech research firm, recently predicted that by 2020 there will be 26 billion Internet-connected devices, an almost 30-fold increase from 2009.

However, this is the first operating system ARM has ever developed.

The mbed OS supports several standards of connectivity, including Wi-Fi, Bluethooth Smart, Thread, and a sub-6-gigahertz version of 6LoWPAN. It also supports many cellular standards, including 3G and LTE. At the same time, ARM is launching mbed server software, which the company says will allow users to gather and analyze data collected from IoT devices.

The OS was designed with power efficiency and battery life in mind. ARM claims it will only take up 256 kilobytes of memory, compared to the several gigabytes worth of storage needed for a smartphone OS. The company hopes developers will use mbed to create devices with battery lives measured in years.

Parts of the OS will be open source, though ARM says it wants to retain control of other parts to ensure mbed remains unfragmented. A recent EETimes study reports that in-house and custom designed systems for IoT devices are on the decline. Open source code already runs in 36 percent of embedded operating systems and is projected to keep rising, with Android and FreeRTOS leading the pack. ARM seems to be trying to balance the advantages of development flexibility with proprietary control, but it remains to be seen how well that plays out.

Chris Rommel from the VDC Research group also told the BBC that while he believed most companies would welcome this news, it was unlikely the mbed OS would find its way into all IoT devices. "There will likely never be any one operating system—or even two or three—that can satisfy the broad ranges of needs of all the various devices that compose the Internet of things. They are just too different."

Already there are some big appliance makers who are sure to resist the mbed OS. GE employs the software Predix in almost all its IoT products, and Samsung is heavily invested into using Tizen for its family of IoT devices. Nest Labs's products run on a proprietary software based on Linux, though that's likely to shift to Android soon due to company's acquisition by Google.

However, that hasn't squelched enthusiasm from other companies yet. ARM will release the OS to hardware manufacturers and other developers before the end of the year, and says 25 companies have already signed up, including Ericsson, Freescale, IBM, NXP, and Zebra. The first devices to use mbed OS are expected to arrive in 2015.

Expedition Brings High Speed Connectivity to the Ocean Floor

Members of the U.S. National Science Foundation's Ocean Observatory Initiative (OOI) are approaching the end of an nearly three month-long cruise during which they installed a fiberoptic cables and power lines that form the backbone of a seafloor observatory in the Pacific Ocean. The observatory will make it possible for oceanographers and other researchers to gather data about the ocean floor in real time from a network of seismometers, cameras, and other sensors hundreds of kilometers off-shore and as deep as 1800 meters beneath the ocean's surface. 

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FAA: Airlines Must Replace Boeing Cockpit Screens to Avoid Wi-Fi Interference

U.S. regulators aren't taking any chances with the discovery that Wi-Fi signals can cause flickering or temporary blank screens in the cockpits of Boeing passenger jets. On Tuesday, the FAA ordered airlines to replace the cockpit displays used by pilots in more than 1,300 Boeing aircraft over the next five years.

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Bright, Bendy Gallium Nitride LEDs

When it comes to light-emitting diodes, both inorganic and organic devices have found their niches. Inorganic LEDs, which beat organic ones hands down in brightness, energy efficiency, and durability, reign in lighting. Organic LEDs, on the other hand, can be tiny and are cheap to manufacture, so they take the prize for large-area, high-resolution and flexible applications such as displays and wearable sensors.

Researchers have now combined the best of inorganic and organic LEDs. They've made bendable inorganic LEDs by growing micrometers-tall gallium nitride rods on graphene. The tiny 50µm x 50µm LEDs glow bright blue and retain their brightness after being bent more than 1000 times. They could lead to inexpensive, high-quality displays and sensors, and could be used in touch panels and smart contact lenses, says Gyu-Chul Yi, a professor of physics at Seoul National University. Yi and his colleagues reported the LEDs in the online journal APL Materials.

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Mantis Shrimp Eyes Inspire Cameras to See Cancer

Millions of years of evolution have given the Mantis shrimp compound eyes to spot delicious meals that it can either spear or club to death in its underwater environment. More recently, the natural design of those eyes has inspired a new camera sensor that could spot cancer cells inside patients' bodies.

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