| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-performance and small objective lens for an optical pickup securing a working distance while having numerical apertures. SOLUTION: The objective lens for the optical pickup that carries out read/ write of information by condensing luminous flux from a light source on an information recording medium comprises two lenses consisting of a first lens having a first surface convex on the light source side and a second surface concave on the light source side, and a second lens having a third surface convex on the light source side and a fourth surface concave on the light source side, in this order from the light source side. Each of the first, third and fourth surfaces has an aspherical surface. |
