| 摘要 |
The control panel comprises a transparent panel (2) of a light conducting material, such as an organic glass e.g. polymethyl methacrylate (PMMA) or polycarbonate, marked with signs or symbols on its front face which are illuminated by a light source (13) fitted into an aperture (12) in the panel. The aperture is shaped so that its edge forms a series of lenses (14) designed to direct light beams through the thickness of the panel to deflectors (17) which reflect the beams towards signs and symbols. The aperture passes from one side of the panel to the other, is basically circular in shape, and the lenses around its edge are convex, have selected focal lengths, and are set in chosen angular positions. The lenses are angled towards the rear face of the panel to allow them to be moulded from the material of the panel. The light is provided by a lamp or luminescent diode. |
