| 摘要 |
<p>Retroreflective elements, such as cube-corner elements or right triangular prisms containing cube-corners, are arranged on articles to define separation surfaces between the elements; in another embodiment, the elements are truncated cube-corners incorporating similar surfaces on the elements themselves. If the surfaces are transparent they will transmit light through the article, rendering it partially transparent and partially retroreflective. The surfaces may be flat or curved. Standard grooving techniques may be employed to construct the elements, using mold cutting tools having flattened or curved tips instead of V-shaped tips; alternatively, electroformed molds may be lapped to include the shape required to produce surfaces. The elements and surfaces may be embodied in sheeting materials or internally illuminated signs.</p> |
