Patent ID: 6345029
Filing Date: 2002-02-05
Classification: G11B

Abstract:
An optical pickup apparatus for use with a first optical disk and a second optical disk, the first optical disk having a different thickness than the second optical disk, the optical pickup apparatus comprising:a disk supporter for selectively loading the first optical disk and the second optical disk; a first light source that can emit a first light beam having a wavelength related to the first optical disk; a second light source that can emit a second light beam having a wavelength related to the second optical disk; an optical path alteration unit that receives the first and second light beams and directs the first and second light beams toward said disk supporter; an annular aperture including an annular shielding region disposed concentrically about an axis of an optical path between said optical path alteration unit and said disk supporter, the annular shielding region adjusting a numerical aperture to provide a different numerical aperture based on the wavelength of the first and second light beams and blocking the first and second light beams incident on the annular shielding region; and an objective lens focusing light beams, passed through said annular aperture, forming a beam spot on the disk supported by said disk supporter.