Tomorrow is Today

Researchers Create Printable Lasers

A way of printing lasers using everyday inkjet technology has been created by scientists. The development has a wide range of possible applications, ranging from biomedical testing to laser arrays for displays. The research is reported in the journal Soft Matter.

A laser is a characteristically “pure” form of light, occupying a very narrow wavelength range, or color. Laser devices are already ubiquitous in modern life; they are used to read data from Blu-Ray discs and deliver high-speed internet around the world, for example. In science and technology, lasers are similarly versatile – being employed for a wide range of purposes such as medical treatment and testing, or space-based remote sensing.

Read more: http://www.laboratoryequipment.com/news/2012/09/researchers-create-printable-lasers

(ht laboratoryequipment)

Swedish Researchers Develop Printable LEDs for “Illuminated Wallpaper”

A great deal of effort has been devoted to trying to produce low-cost organic light-emitting diodes (OLEDs) via printing processes—inkjet, screen, and gravure. So far, though, making these devices has demanded tightly controlled conditions (including artificial atmospheres).

Now, Andreas Sandström and collaborators at the Umea University Physics Department in Sweden and the Technical University of Denmark have flipped the switch on light-emitting electrochemical cells (LECs). These devices consist of a mobile-ion active layer sandwiched between a cathode-coated base layer and a semitransparent anode layer.

…The researchers are particularly enthusiastic about two points: first, the device is fabricated in open atmosphere. And second, the device operates even if the deposited layers are very uneven; it does not require the tight tolerances that OLEDs demand, and light emission remains highly uniform over the test device’s 300-square-millimeter surface.  

Or, as they put it in their paper, “the fabrication yield of the roll-coated LECs is found to be very satisfying, primarily due to the fault-tolerant device geometry with a thick active layer and air-stable materials.”

As a bonus, because anode and cathode layers are transparent, the device shines from both its top and bottom surfaces.

(via Printing Process Makes Illuminating ‘Wallpaper’ - IEEE Spectrum)

Stanford researchers synthesize printable, electrically conductive gel

Stanford researchers have invented an electrically conductive gel that is quick and easy to make, can be patterned onto surfaces with an inkjet printer and demonstrates unprecedented electrical performance. The Jell-O-like material may have applications in areas as widespread as energy storage, medical sensors and biofuel cells. It is a kind of conducting hydrogel – a jelly that feels and behaves like biological tissues, but conducts electricity like a metal or semiconductor.

[read more] [Stanford News] [paper] [image credit: Stanfort/L.A. Cicero]

(via nextbigfuture, ht futurescope)

Researchers ‘Print’ Polymers That Bend Into 3-D Shapes

Researchers at the University of Massachusetts Amherst employed photographic techniques and polymer science to develop a new technique for printing two-dimensional sheets of polymers that can fold into three-dimensional shapes when water is added. The technique may lead to wide ranging practical applications from medicine to robotics.

The technique could be used to direct growth of blood vessels or tissues in the laboratory.

Researchers used a photomask and ultraviolet (UV) light to “print” a pattern onto a sheet of polymers, a technique called photolithography. In the absence of UV exposure, the polymer will swell and expand uniformly when exposed to water, however when polymer molecules within the sheet were exposed to UV light they became crosslinked—more rigidly linked together at a number of points—which prevented them from expanding when water was added. Patterning the amount of crosslinking across an entire sheet allowed researchers to control how much each area swelled. A second exposure to a carefully selected pattern of UV light allowed them to create specific 3-D shapes.

[via] [more] [paper] [credit: Zina Deretsky, National Science Foundation]

(via futurescope)

Metamaterial Printer Promises Human-Scale Invisibility Cloaking:

The science of stealth has long been a matter of fading into already obscure environments—the night sky, say, or the deep sea. But engineers are now developing materials that could hide anything in plain sight. Instead of bending light inward, like water and glass do, these optical metamaterials bend it outward, guiding photons around an object like river water around a stone. The metal alloys in metamaterials are arranged in a grid fitted with openings smaller than the wavelengths of visible light (400 to 700 nanometers). Light cannot pass unimpeded through any space smaller than its own wavelength, so it gets trapped in the grid. Captured photons can be stored, manipulated or, in this case, funneled around an object and returned to their original course. An object cloaked by a perfectly made metamaterial would cast no shadow.

(via The Newest Revolutions in Metamaterials Bring Invisibility Within Reach | Popular Science)