| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an objective lens optical system capable of improving light use efficiency and information reading/writing performance of an optical recording medium by reducing unnecessary lights and suppressing side lobes, and an optical pickup device. <P>SOLUTION: The objective lens optical system has an exclusive area used for one of a plurality of types of optical recording media and a shared area used for the rest of the plurality of types of optical recording media. The exclusive area and the shared area are disposed so that point-image intensity other than a main lobe defined by predetermined expression is equal to or less than 5%. <P>COPYRIGHT: (C)2009,JPO&INPIT |
