| abstract |
Provided are an optical pickup device, an objective optical element, and an optical information recording/reproducing device capable of recording and/or reproducing information to/from optical discs of different types in a compatible manner. The optical pickup device includes a first light source, a second light source, a third light source, and an objective optical element. The objective optical element has an optical surface having at least two areas, i.e., a central area and a peripheral area around the central area. The central area has a first optical path difference giving structure and the peripheral area has a second optical path difference giving structure. The objective optical element gathers the light flux passing through the central area and the peripheral area of the objective optical element so as to respectively record and/or reproduce information onto/from an information recording surface of a predetermined optical disc. Moreover, the first optical path difference giving structure has a coaxial circular band structure having a step and the step difference amount of the first optical path difference giving structure has a predetermined step difference amount. |