| 摘要 |
<p>An optical pickup device comprising a first light source emitting a first light beam, a second light source emitting a second light beam, a third light source emitting a third light beam, and an objective optical element, wherein the optical surface of the objective optical element has at least two regions, a central region and a peripheral region, the central region has a first optical path difference imparting structure and the peripheral region has a second optical path difference imparting structure, the objective optical element condenses the first light beam, the second light beam and the third light beam passed through the central region, and condenses the first light beam and the second light beam passed through the peripheral region, and the first and second optical path difference imparting structures have a basic structure as a predetermined optical path difference imparting structure, respectively.</p> |
