Researchers from the Technical University of Denmark demonstrated a new nanotechnology-based printing technique that produces long-lasting color images on plastic at resolutions up to 127,000 dots per inch, many times more detailed than traditional laser printers. The system uses a laser to alter the structure of nanoscale structures on the plastic material. (A nanometer is one-billionth of a meter; a human hair is around 60,000 nanometers in diameter.) The nanoprinting technique could also lead to new kinds of 3D displays or invisible watermarks. From New Scientist : The surface of the plastic is shaped so that it has lots of tiny pillars, one roughly every 200 nanometers. A thin film of the element germanium is then spread over the plastic. Heat from a laser melts the germanium on each pillar, morphing its shape and thickness. As a result, it reflects a specific color. The coating protects the shapes of the newly carved nanostructures. Resonant laser printing of structural colors on high-index dielectric metasurfaces (ScienceAdvances)
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New ultra-high resolution printer makes colors from nanostructures
An anonymous reader writes: A recently released draft of the National Institute of Standards and Technology’s digital identity guidelines has met with approval by vendors. The draft guidelines revise password security recommendations and altering many of the standards and best practices security professionals use when forming policies for their companies. The new framework recommends, among other things: “Remove periodic password change requirements.” There have been multiple studies that have shown requiring frequent password changes to actually be counterproductive to good password security, said Mike Wilson, founder of PasswordPing. NIST said this guideline was suggested because passwords should be changed when a user wants to change it or if there is indication of breach. Read more of this story at Slashdot.