| 摘要 |
<p>The section of the channels is pref. of a parallelogram form with the option of a plain or profiled internal region at the inner side or base of the channel. This region is not covered with dark, light-absorbing material. The form of the profile is arranged such that a shadow region is formed within the channel thus preventing light transmitted through the base of the channel escaping, when illuminated from the rear with the element orientated to produce a dark appearance. The opaque, translucent layer is pref. a material which evenly diffuses light falling upon it, such as white perspex, or a fluorescent material with which an ultra-violet light source can be used. A layer of dark paint is applied to achieve the dark, light-absorbing surface. A reflective paint coating may be applied underneath the dark surface to achieve a more even dark appearance where required. The channels may be produced by machining the form in solid material or by fabrication of the channel side strip elements from, e.g. sheet metal by pressing and bending.</p> |
