Optical disk data storage system with radiation-transparent air-bearing

Abstract

An optical disk drive has an air-beating slider formed of transparent material and located adjacent the surface of the optical disk. In the manner of conventional magnetic disk drives, the slider is maintained in close relationship with the disk surface by an air-bearing generated by the rotating disk and the shape of the slider's air-bearing surface (ABS). The slider has a lens section located on its back side opposite the side with the ABS. In the preferred embodiment the lens section is at least a hemisphere and the lens section and slider are formed of the same material and thus have the same index of refraction, n. The lens section and slider are transparent to light from the disk drive's light source and together form a super-hemispherical solid immersion lens (SIL). The slider's ABS is maintained within one wavelength of the surface of the optical disk. The light from the disk drive's light source is focused by the super-hemispherical SIL to a point on the slider ABS. The light is coupled through the air-bearing gap via the evanescent field to the data layer on the optical disk. The focused spot size on the disk data layer is thus reduced by a factor of n.sup.2 from what it would otherwise be without the super-hemispherical SIL provided by the lens section and transparent slider.