OPTICAL PICKUP AND OPTICAL DISC DISK DEVICE, COMPUTER, OPTICAL DISC DISK PLAYER, OPTICAL DISC DISK RECORDER

摘要

Provided are a compact and inexpensive optical pickup having fewer a reduced number of parts for an optical pickup capable of recording and reproducing a high density optical disk (BD) using a blue-violet laser light source, and an optical disc disk device. The traveling range La of a coupling lens (5) is the position at one end of the coupling lens (5) when recording or reproducing a DVD by red laser light and the position at the other end of the coupling lens (5) when recording or reproducing a CD by infrared laser light. The traveling range Lb of the coupling lens (5) for correcting the spherical aberrations according to the thickness of the protective substrate of the information recording surface in the BD caused by blue-violet laser light fits into the traveling range La of the coupling lens (5) because the spherical aberrations caused by the thickness of the protective substrate of the information recording surface in the BD are corrected by blue-violet laser light.