Optical pickup

摘要

An optical pickup capable of effectively reducing chromatic aberration is provided. In the optical pickup, a collimating lens (103) including a diverging lens (103b) with diverging power and a focusing lens (103a) with focusing power is arranged on the optical path between a light source (104) and an objective lens (101), wherein assuming that the total focal distance of the collimating lens is f and the focal distance of the diverging lens is fn, the collimating lens satisfies the relationship -1.5 > f/fn. The optical pickup is compatible with both existing digital versatile disks (DVDs), and high-definition (HD)-DVDs, which are not standardized yet, but need a blue light source near 405nm and an objective lens having a numerical aperture of 0.6 or more.