Patent ID: 7342869
Filing Date: 2008-03-11
Classification: G11B

Abstract:
1. An optical-recording-medium playback apparatus comprising: a light-emitting unit configured to emit light; an optical recording medium having a plurality of recording layers from which information can be optically read out; a flying optical head configured to fly above the optical recording medium supported by an air flow and focus the light emitted from the light-emitting unit onto one of the recording layers of the optical recording medium, the flying optical head having a lens configuration including at least a solid immersion lens and an objective lens, the lens configuration having a numerical aperture NA of more than 1, the solid immersion lens having a surface which faces a surface of the optical recording medium with a gap therebetween of less than 100 nm; an optical member configured to focus returning light from the optical recording medium responsive to the light focused by the optical head; a light-receiving unit configured to receive the returning light focused by the optical member; and a focal-position-adiusting means disposed between the solid immersion lens and the objective lens, configured to adjust a focal position of the light focused by the optical head in the thickness direction of the optical recording medium.