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Soulskill

concealment sends this quote from the NY Times: "Today’s chips are made on large wafers that hold hundreds of fingernail-sized dies, each with the same electronic circuit. The wafers are cut into individual dies and packaged separately, only to be reassembled on printed circuit boards, which may each hold dozens or hundreds of chips. PARC researchers have a very different model in mind. ... they have designed a laser-printer-like machine that will precisely place tens or even hundreds of thousands of chiplets, each no larger than a grain of sand, on a surface in exactly the right location and in the right orientation. The chiplets can be both microprocessors and computer memory as well as the other circuits needed to create complete computers. They can also be analog devices known as microelectromechanical systems, or MEMS, that perform tasks like sensing heat, pressure or motion. The new manufacturing system the PARC researchers envision could be used to build custom computers one at a time, or as part of a 3-D printing system that makes smart objects with computing woven right into them."

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MrSeb writes "Electrical engineers and material scientists at MIT have created a fiber-borne laser that could be woven to form a flexible display that could project different 3D images in any number of directions, to any number of viewers. MIT's fiber is similar to standard telecoms fiber, but it has a tiny droplet of fluid embedded in the core. When laser light hits the fluid, it scatters, effectively creating a 360-degree laser beam. The core is then surrounded by layers of liquid crystal, which can be controlled like 'pixels,' allowing the laser light to escape from specific points anywhere along the length of the fiber. This means that you could have a display that shows one picture on the 'front' and another on the 'back' — or different, glasses-free 3D images for everyone sitting in front and behind. In the short term, the laser fiber is more likely to have a significant application in photodynamic therapy, an area of medicine where drugs are activated using light. Photodynamic therapy is one of the only ways to treat cancer in a relatively non-invasive and non-toxic manner. MIT's laser could be threaded into almost any part of the body, where the ability to produce pixels of laser light at any point along its length would make it a highly accurate device."


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The Senate just drove a stake into the Navy’s high-tech heart. The directed energy and electromagnetic weapons intended to protect the surface ships of the future? Terminated.

The Free Electron Laser and the Electromagnetic Railgun are experimental weapons that the Navy hope will one day burn missiles careening toward their ships out of the sky and fire bullets at hypersonic speeds at targets thousands of miles away. Neither will be ready until at least the 2020s, the Navy estimates. But the Senate Armed Services Committee has a better delivery date in mind: never.

The committee approved its version of the fiscal 2012 defense authorization bill on Friday, priced to move at $664.5 billion, some $6.4 billion less than what the Obama administration wanted. The bill “terminates” the Free Electron Laser and the railgun, a summary released by the committee gleefully reports.

“The determination was that the Free Electron Laser has the highest technical risk in terms of being ultimately able to field on a ship, so we thought the Navy could better concentrate on other laser programs,” explains Rick DeBobes, the chief of staff for the committee. “With the Electromagnetic Railgun, the committee felt the technical challenges to developing and fielding the weapon would be daunting, particularly [related to] the power required and the barrel of the gun having limited life.”

Both weapons are apples in the eye of the Office of Naval Research, the mad scientists of the Navy. “We’re fast approaching the limits of our ability to hit maneuvering pieces of metal in the sky with other maneuvering pieces of metal,” its leader, Rear Adm. Nevin Carr, told me in February. The answer, he thinks, is hypersonics and directed energy weapons, hastening “the end of the dominance of the missile,” Adm. Gary Roughead, the top officer in the Navy, told me last month. With China developing carrier-killer missiles and smaller missiles proliferating widely, both weapons would allow the Navy to blunt the missile threat and attack adversaries from vast distances.

And both have recently experienced technical milestones that made researchers squeal with glee.

In December, the Navy corralled reporters to Dahlgren, Virginia, to watch a railgun the size of a schoolbus fire a 23-pound bullet using no moving parts — just 33 megajoules of energy, a world record. (A prototype of a ship-ready railgun is pictured above.)

And this winter, the Free Electron Laser, the most powerful and sophisticated laser there is, boasted two big advances within a month. In January, its 14-kilowatt prototype passed tests that injected enough energy into it to get it up to a megawatt’s worth of death ray — a “remarkable breakthrough,” nine months ahead of schedule, the Office of Naval Research crowed. The next month, its testers at the Jefferson Lab in Newport News added even more power. Researchers think it could be far more than a weapon: it might act as a super-sensor, and Yale scientists use it to hunt for cosmic energy.

Shipboard power is the question mark surrounding both weapons. The laser and the railgun require diverting power from a ship’s generators in order to fire. The Navy’s waved that away, saying that its onboard generators — especially the superpowerful ones in development — can handle the megawattage necessary, and the Free Electron Laser’s guts are shaped like a racetrack to “recycle” some of the energy injected into it. But both plans rely on the power efficiency of ships that aren’t built yet.

Neither comes cheap, either. The Navy’s spent some $211 million since 2005 developing the railgun. Its milestones with the Free Electron Laser — in development in some form since the ’90s — led it to ask Congress for $60 million in annual directed-energy research funds, most of which go to the superlaser. Needless to say, a Senate panel facing a huge budget crunch was unsympathetic.

The Office of Naval Research didn’t respond by press time. The process of passing a defense budget making it through no fewer than four committees and two floor votes, so it’s not like these programs cease to exist. But unless the Navy makes a big push for its futuristic weapons, both of them will die on the drawing board.

Photo: Spencer Ackerman

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