| 摘要 |
PURPOSE:To improve a virtual axial outside reproducing characteristic without improving an axial outside reproducing characteristic of a lens itself, by constituting the titled device so that a light emitting point of a light radiating means is selected in response to a shift between an optical axis of the device and an optical axis of an objective lens, and a light beam is made incident vertically on the surface of the objective lens. CONSTITUTION:A semiconductor laser 1 has, for instance, plural light emitting points, and in accordance with a tracking shift, an optimum light emitting point is selected. Therefore, by inputting a tracking error signal to an optical axis shift signal generating circuit 12 and detecting a DC component of the tracking error signal, an optical axis shift signal is generated, and by applying this optical axis shift signal to a light emitting point selecting circuit 13, only an optimum light emitting point is driven selectively. In such a way, even if an axial outside reproducing characteristic of the objective lens itself is not so good, a satisfactory reproducing characteristic can be obtained. |
