Lithography is a method of printing originally based on the immiscibility of oil and water. The printing is from a stone (lithographic limestone) or a metal plate with a smooth surface. It was invented in 1796 by German author and actor Alois Senefelder as a cheap method of publishing theatrical works. Lithography can be used to print text or artwork onto paper or other suitable material.

Lithography originally used an image drawn with oil, fat, or wax onto the surface of a smooth, level lithographic limestone plate. The stone was treated with a mixture of acid and gum arabic, etching the portions of the stone that were not protected by the grease-based image. When the stone was subsequently moistened, these etched areas retained water; an oil-based ink could then be applied and would be repelled by the water, sticking only to the original drawing. The ink would finally be transferred to a blank paper sheet, producing a printed page. This traditional technique is still used in some fine art printmaking applications.

  • Atomic precision: technologies for the next-but-one generation of microchips

    Atomic precision technologies for the next but one generation of microchips picture 2 Image 2: The coating of mirrors is carried out with atomic precision at Fraunhofer IOF in Jena. © Fraunhofer IOF, Jena, Germany

    In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.

  • Photovoltaik nach dem Vorbild der Rose

    Photovoltaik nach dem Vorbild der Rose | Biomimetik: Die Epidermis eines Rosenblütenblatts wird in einer transparenten Schicht nachgebildet; diese wird in die Vorderseite einer Solarzelle integriert. Abbildung: Guillaume Gomard, KIT

    Mit einer Oberfläche wie bei Pflanzen können Solarzellen mehr Licht aufnehmen und damit mehr Strom erzeugen. Forscher des Karlsruher Instituts für Technologie (KIT) reproduzierten die epidermalen Zellen von Rosenblütenblättern, die eine besonders starke Antireflexwirkung besitzen, und integrierten die transparente Nachbildung in eine organische Solarzelle. Dies führte zu einer relativen Erhöhung der Effizienz von zwölf Prozent. Darüber berichten die Wissenschaftler in der Zeitschrift Advanced Optical Materials (DOI: 10.1002/adom.201600046).