| 摘要 |
<p>A dry erase whiteboard, or other writing or projection surface assembly, is formed from a backing substrate having a surface, and an inner conductive layer and an outer conductive layer supported by the surface of the substrate. A resistive layer is positioned between the inner conductive layer and the outer conductive layer. The resistive layer has an electrical resistivity that varies in response to mechanical deformation and/or stress to provide a variable effective resistance between the inner and outer conductive layers. The outer conductive layer can be immovably attached to a fixed frame, which is mounted to the substrate, in spaced apart relation to the inner conductive layer to define an air gap therebetween and a tensioning assembly can maintain the outer conductive layer in a tensioned state. Alternatively, the resistive layer is fixed directly to each conductive layer to provide a substantially air free environment therebetween.</p> |
