摘要:
A method and apparatus for recording and/or reproducing holographic data and a holographic information storage medium, wherein the apparatus for recording and/or reproducing holographic information includes an optical pickup emitting light onto a holographic information storage medium and receiving the emitted light. The optical pickup includes: a light source unit emitting a signal beam and a reference beam in a recording mode; and a focusing optical system focusing the signal beam and the reference beam on one focal point in the holographic information storage medium so that information can be recorded by using an interference pattern formed along a depth direction of the holographic information storage medium in the vicinity of the focal point, wherein the numerical aperture of the focusing optical system for the signal beam is different from the numerical aperture of the focusing optical system for the reference beam.
摘要:
A method and apparatus for recording and/or reproducing holographic data and a holographic information storage medium, wherein the apparatus for recording and/or reproducing holographic information includes an optical pickup emitting light onto a holographic information storage medium and receiving the emitted light. The optical pickup includes: a light source unit emitting a signal beam and a reference beam in a recording mode; and a focusing optical system focusing the signal beam and the reference beam on one focal point in the holographic information storage medium so that information can be recorded by using an interference pattern formed along a depth direction of the holographic information storage medium in the vicinity of the focal point, wherein the numerical aperture of the focusing optical system for the signal beam is different from the numerical aperture of the focusing optical system for the reference beam.
摘要:
A method of recording holographic information includes recording a hologram mark and a homogeneous mark in a holographic data storage medium with a volume to alternatively locate the hologram mark and the homogeneous mark. The hologram mark has a varied refractive index distribution due to constructive/destructive interferences between two light beams and indicates information, while the homogeneous mark has a more uniform refractive index distribution than the hologram mark.
摘要:
An apparatus for recording/reproducing holographic data and a method of adjusting a position of a recording layer. While an objective lens focusing first and second lights having different wavelengths on a holographic data storage medium including first and second reflective layers reciprocatingly moves in a direction of an optical axis, a focus movement unit, which moves a focus of the second light in the direction of the optical axis until a time difference between a first detection signal generated when the first light is reflected from the first reflective layer and a second detection signal generated when the second light is reflected from the second reflective layer becomes a value corresponding to a position of a desired recording layer, is controlled to move a focal position of the second light so that the focal position of the second light can be adjusted to the position of a desired recording layer.
摘要:
A holographic information recording and/or reproducing apparatus includes: a light source to emit light; a polarization conversion device to form a polarized signal beam and an orthogonal polarized reference beam; an optical path forming optical system to separate the optical paths of the signal beam and the reference beam; a focus adjustment optical system disposed on the optical path of at least one of the signal beam and the reference beam, and to vary a position of a focus of at least one of the signal beam and the reference beam in a depth direction of the holographic information storage medium; an objective lens to focus the signal beam and the reference beam in the holographic information storage medium, and form an interference pattern to record information; and a 4f relay system disposed on an optical path between the focus adjustment optical system and the objective lens.
摘要:
A holographic information recording and/or reproducing apparatus including: a light source unit emitting reference light and signal light; a first optical path guiding unit guiding the lights to cross; a second optical path guiding unit including a first polarization converter located on an optical path of one of the reference and signal lights, a first polarization beam splitter located at a crossing point of the reference light and the signal light, an optical path converter guiding the reference light and the signal light so that they cross again, a second polarization converter located on an optical path of the signal light before the signal light crosses the reference light, and a second polarization beam splitter uniting the optical paths of the reference light and the signal light; and an objective lens unit illuminating the reference light and the signal light onto one side of a holographic information storage medium.
摘要:
An optical pickup of a holographic data recording/reproducing apparatus that emits light to a reflective holographic data storage medium in which a substrate, a reflection layer, a recording layer, and a cover layer are sequentially stacked, and receives the emitted light, the optical pickup including: a first light source unit to emit, during a recording operation, a signal beam having a first polarization and a reference beam having a second polarization perpendicular to the first polarization along the same optical path; and a main lens unit having a refractivity that varies according to a polarization of a passing light, so as to cause the signal beam to be reflected from the reflection layer then focused on a focal point, and to cause the reference beam to pass through the cover layer then be directly focused on the focal point.
摘要:
A holographic information recording and/or reproducing apparatus includes a light pickup optical system and a recording power control unit. The light pickup optical system illuminates reference light and signal light onto an information storing medium. The recording power control unit controls the light pickup optical system such that recording power of the reference light is the same as that of signal light.
摘要:
A holographic information recording and/or reproducing apparatus includes: a light source to emit light; a polarization conversion device to form a polarized signal beam and an orthogonal polarized reference beam; an optical path forming optical system to separate the optical paths of the signal beam and the reference beam; a focus adjustment optical system disposed on the optical path of at least one of the signal beam and the reference beam, and to vary a position of a focus of at least one of the signal beam and the reference beam in a depth direction of the holographic information storage medium; an objective lens to focus the signal beam and the reference beam in the holographic information storage medium, and form an interference pattern to record information; and a 4f relay system disposed on an optical path between the focus adjustment optical system and the objective lens.
摘要:
A holographic information recording and/or reproducing apparatus including: a light source unit emitting reference light and signal light; a first optical path guiding unit guiding the lights to cross; a second optical path guiding unit including a first polarization converter located on an optical path of one of the reference and signal lights, a first polarization beam splitter located at a crossing point of the reference light and the signal light, an optical path converter guiding the reference light and the signal light so that they cross again, a second polarization converter located on an optical path of the signal light before the signal light crosses the reference light, and a second polarization beam splitter uniting the optical paths of the reference light and the signal light; and an objective lens unit illuminating the reference light and the signal light onto one side of a holographic information storage medium.