| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup device, an objective optical element and optical information recording and reproducing device which can appropriately perform recording and/or reproducing for three kinds of disks having different recording density. <P>SOLUTION: The optical pickup device has a first light source emitting first luminous flux, a second light source emitting second luminous flux, a third light source emitting third luminous flux and an objective optical element. In the objective optical element, an optical plane has at least a center region and a peripheral region. The center region has a first optical path difference giving structure, and the peripheral region has a second optical path difference giving structure. A first best focus and a second best focus are formed by third luminous flux transmitting through the first optical path difference giving structure, and the first best focus and the second best focus satisfies the prescribed conditions. <P>COPYRIGHT: (C)2009,JPO&INPIT |
