OBJECTIVE LENS, OPTICAL PICK-UP DEVICE, AND OPTICAL DISK DEVICE

摘要

An optical pickup device and optical disk device are provided realizing at least one of thickness reduction, size reduction and suppression against characteristic deterioration even where coping with various wavelengths including a blue laser. An optical pickup comprises light sources of a plurality of wavelengths, unit structured for causing at least a part of the light emitted from the sources to pass a same optical path; and focusing unit. The focusing unit includes at least first and second parts, the first part being to focus a wavelength different from a wavelength to be focused by the second part.