Category Technology/Electronics

New research shows that miniscule amounts of impurities in vacuum are being incorporated into OLEDs during fabrication and leading to large variations in lifetime. By reducing the time OLEDs spend in the deposition chamber during fabrication, impurities can be reduced and lifetime enhanced. Analysis of the impurities indicates sources that include previously deposited materials and plasticizers from chamber components. Credit: Hiroshi Fujimoto and William J. Potscavage, Jr.

Reproducibility is a necessity for science but has often eluded researchers studying the lifetime of organic light-emitting diodes (OLEDs). Recent research from Japan sheds new light on why: impurities present in the vacuum chamber during fabrication but in amounts so small that they are easily overlooked...

Optical setup for two wavelength digital hologram recordings of toy puppets. M, mirror; BS, beam splitter; BE, beam-expander; RP, reflecting prism; CCD, charge coupled device; D, rotating diffuser; R, rotator and O, object.

Digital holography: Noise practically eliminated. Digital Holography is a powerful imaging technique for 3D vision and display systems. However, the use of coherent light sources introduces annoying visual phenomenon, namely speckle noise, an intrinsic interference effect due to the laser. Such coherent noise, superposing to digital holograms, severely degrades the corresponding reconstruction quality in holographic systems...

This image shows examples of engineered 3-D silk constructs. Credit: Silklab, Department of Biomedical Engineering, School of Engineering, Tufts University

Tufts University engineers have created a new format of solids made from silk protein that can be preprogrammed with biological, chemical, or optical functions, eg mechanical components that change color with strain, deliver drugs, or respond to light. Using a water-based fabrication method based on protein self-assembly, the researchers generated 3D bulk materials out of silk fibroin, the protein that gives silk its durability. Then they manipulated the bulk materials with water-soluble molecules to create multiple solid forms, from nano- to micro-scale, that have embedded, pre-designed functions.

Eg, they created a surgical pin that ...

In the proposed system, a carbon nanotube is suspended between two leads, below a tip electrode, and above a gate. The pair of leads and the tip are two separate electron reservoirs with different temperatures. Electrons can tunnel between the nanotube and the reservoirs. Although electron exchange between the two reservoirs is prevented, electron-electron interaction couples the two reservoirs, allowing for a heat flow. Credit: A. Vikström et al. ©2016 American Physical Society

Illustrating the unusual way things work on the nanoscale, scientists have designed a new nanoelectromechanical system (NEMS) that produces mechanical motion due to the interactions between electrons—yet unlike similar systems, this system does not require any electric current...