| 摘要 |
<p>The present invention relates to a device for reading from or writing to an optical recording medium which has at least two information carrier layers (9, 10) spaced apart from one another, as well as a light source (1, 1', 1''), an optical unit and a detection unit. The object of the present invention is to propose a device of this type which permits a plurality of information carrier layers to be read from and/or written to simultaneously using light of a single wavelength. According to the invention, a partial beam generating element (4, 1', 1'', 19) is present for this purpose, which element emits two partial beams (5, 6, 2', 2'') which differ in terms of polarization direction and propagation behaviour. The present invention is advantageously employed in devices for reading from or writing to optical recording media such as, for example, CD, CD-ROM, DVD, laser disk or the like. <IMAGE></p> |
