Light-reflecting characteristics of optically rewritable electronic paper

Light-reflecting characteristics play a crucial role in optically rewritable liquid crystal display (electronic paper). By using a special optimizer software, light-reflecting characteristics of the twisted nematic cell were calculated. The achieved values of the normalized reflection coefficients range within ∼ 0.03 - 0.43, which is comparable or better than other commercial technologies. The calculated contrast ratio of the device is 10 : 1. A 2D image, which can be displayed on the electronic paper was obtained. Comparison of the simulated background color and contrast ratio is very similar with the results, which were obtained in experimental cells of other studies. Our calculations indicate that angular dependence of the reflectance coefficient is almost uniform within a wide range of viewing angles.

Optically Rewritable Liquid Crystal Displays: Characteristics and Performance

Recent achievements in the photoalignment technique for fabrication of optically rewritable electronic paper with high performance characteristics are surveyed with emphasis on temporal constraints on the exposure process. The possibility of creating electrode-free electronic paper has very important practical aspects. However, many existing studies do not include sufficient analysis on how to achieve acceptable reflective characteristics within short exposure time. In order to achieve this goal, we have applied the rotational diffusion model. We find that the parameters of the diffusion model can be adjusted to get acceptable light-reflecting characteristics within 10 s of exposure. In comparison with the long-time exposure, the reflectance coefficient reduces by 24%. The route to material improvements for optimized e-paper device is discussed.

Fibras artificiales

Este trabajo explora la forma en que los actuales métodos y enfoques archivísticos están seriamente cuestionados por los desafíos que provoca la transformación digital. La disponibilidad de los documentos digitales ha supuesto que a los usuarios se le planteen nuevas necesidades y se abran nuevas posibilidades, incluidos los nuevos modos de consultar. La naturaleza de los mismos archivos está cambiando –están pasando de ser colecciones de textos individuales a ser datosminuciosamente estudiados para darles sentido. Han aparecido nuevas herramientas y técnicas que ya están disponibles y que ofrecen nuevas y radicales posibilidades para la investigación, pero esto comporta nuevos retos en cuanto a la confianza y al gran volumen de documentos a tratar. Los enfoques tradicionales que atribuyen metadatos para facilitar la búsqueda del material relevante y la consideración de los documentos digitales como algo similar al papel electrónico no son viables. Lo que se necesita es una nueva aproximación en la que los archiveros y los investigadores vean los archivos como colecciones de datos que son susceptibles de análisis usando toda una gama de sofisticadas herramientas y que son capaces de ser interpretados con toda una gama de fórmulas diferentes. This article explores how current methods and approaches in archives are under serious challenge because of the changes brought about by the move to the digital. The availability of digital records hasmeant that new needs and new possibilities have opened up for users, including new ways of reading. The nature of archives themselves are changing—they are moving from being collections of individual texts to be pored over to data to be made sense of. New tools and techniques have emerged and are available now which offer radical new possibilities for research, but these bring new challenges about trust and the sheer volume of records to be handled. The traditional approaches of applying metadata to facilitate the finding of relevant material and of regarding digital documents as something like electronic paper is no long viable. What is needed is a new approach in which archivists and scholarly researchers see archives as collections of data which are capable of analysis by a range of sophisticated tools and which are capable of being interpreted in a range of different ways.