Electrophoretic Displays for Urban Traffic Information and Control

“用于城市交通信息和控制的电泳显示器”项目关注的是利用电泳和动态反向反射技术开发新的显示媒体。研究人员寻求开发双稳态显示技术，该技术使用电泳（粒子在电场影响下的运动），适用于大规模户外应用，并且可以切换反向反射。这将导致显示器在需要时表现得像静态交通标志，但在其他情况下看起来是看不见的。该项目需要开发彩色反光颗粒，这些颗粒可以嵌入透明的胶体介质中，然后通过平移和旋转运动对电场的存在做出反应。这将使颜色变化和激活/去激活反射率。这些颗粒必须部分镀银，然后通过各种沉积过程“变黑”。保护容器必须位于透明电极的一侧，既允许产生电场，又允许颗粒的可见性。一些样品已经用氧化铟锡构建，作为当前项目的一部分，将沿着这条路线进行更多的研究。最初计划的应用是一组与交通信号控制器交替设置的路面标志，这些标志看起来很亮，对绿灯的运动有反射作用，但对任何其他车辆来说都是黑暗的，几乎看不见。这将大大改善导航，同时减少在复杂的十字路口，特别是在夜间可见的杂乱和混乱。“用于城市交通信息和控制的电泳显示器”项目是信息技术和民用基础设施发展的一个很好的结合。通过利用允许微小颗粒在电场影响下移动和旋转的物理现象，可以构建动态的标志和其他形式的显示，使用很少的电力，不需要任何形式的直接照明，并且可以在恶劣的环境中使用，例如嵌入人行道，但它们在夜间可见，看起来比传统的花哨的高速公路标志更“自然”。它们不需要外部照明，因为它们使用了一种称为可切换反反射率的技术，可以在需要时将汽车前灯的光线反射回驾驶员身上。因此，它们不会增加视觉混乱，混淆，以及大多数与公路相关的夜间照明标志的典型美学。基本的电泳技术来源于目前用于生产小型电子显示器、手表和各种形式的“电子纸”的方法。最初，研究人员将重点放在与高速公路相关的应用上，如复杂十字路口的动态路面标记、可变信息标志和可变路面标记。在未来，可以考虑其他应用，如机场和滑行道的标志，可以改变颜色的路边油漆，以及隧道墙壁上的信息。

The project "Electrophoretic Displays for Urban Traffic Information and Control" is concerned with the development of new display media exploiting the technologies of electrophoresis and dynamic retroreflectivity. The investigators seek to develop bi-stable display technology that uses electrophoresis (the movement of particles under influence of an electric field) that is suitable for large-scale outdoor applications, and that is switchably retroreflective. This will result in displays that act like static traffic signs when that is desirable, but which are seemingly invisible otherwise. The project requires the development of colored retroreflective particles that can be embedded in a transparent colloidal medium, and then made to react to the presence of an electric field with both translational and rotational movements. This will enable both color changes and the activiation/de-activation of retroreflectivity. The particles must be partially silvered, and then "blackened" via various deposition processes. The protective container must consist on one side of a transparent electrode, allowing for both the generation of an electric field but also the visibility of the particles. Some samples have been constructed with indium tin oxide, and more research along these lines will be conducted as part of the current project. The initial planned application is a set of pavement markers that alternate with the setting of the traffic signal controller, and which appear to be bright and reflective to that movement with the green light, but dark and nearly invisible to any other vehicles. This will greatly improve guidance while reducing visible clutter and confusion at complicated intersections, particularly at night.The project "Electrophoretic Displays for Urban Traffic Information and Control" is a very nice blend of information technology and civil infrastructure development. By exploiting physical phenomena that allow tiny particles to move and rotate under the influence of electric fields, signs and other forms of displays can be constructed that are dynamic, use very little power, require no form of direct illumination, and can be used in harsh environments such as embedded in pavement, yet they are visible at night and look much more "natural" than traditional garish highway signs. They do not require external illumination because they use a technology called switchable retroreflectivity to reflect light from vehicle headlamps back to drivers when it is desired to do so. As a result, they do not add to visual clutter, confusion, and the poor aesthetics typical of most highway-related nighttime illuminated signs. The basic electrophoretic technology is derived from methods used currently to produce small-scale electronic displays, wrist watches, and various forms of "electronic paper." Initially, investigators are focusing on highway-related applications such as dynamic pavement markers at complicated intersections, variable message signs, and variable pavement markings. In the future, other applications such as airfield and taxiway signage, curb paint that can change color, and messages on tunnel walls can be considered.