Abstract: Provided are an optical pickup device and an optical disk drive including the same. The optical pickup device includes a quarter-wave plate (QWP) that is disposed parallel to an objective lens and a reflection mirror that reflects a beam back onto the QWP after the beam passed through the QWP. The optical pickup device also includes a polarization mirror that is disposed between the objective lens and the QWP, and which reflects the beam which is generated from a light source onto the QWP, and allows the beam reflected by the reflection mirror to pass through to the objective lens.

Abstract: An apparatus includes a waveguide configured to deliver light to a transducer region. The apparatus also includes a plasmonic transducer that has two metal elements configured as side-by-side plates on a substrate-parallel plane with a gap therebetween. The gap is disposed along the substrate-parallel plane and has an input end disposed proximate the transducer region and an output end. The transducer is configured to provide a surface plasmon-enhanced near-field radiation pattern proximate the output end in response to the light received by the waveguide.

Abstract: A transducer comprises a slider and a laser arrangement. The laser arrangement is configured to heat a region of a magnetic medium in proximity to the slider and produce modulated laser light to cause heat-induced modulation of the slider. The laser arrangement is configured to couple laser light at a power that reduces a coercivity of magnetic material at the region for writing data to or erasing data at the region, and couple modulated laser light to cause heat-induced modulation of the slider at a power lower than the power for writing data to or erasing data at the magnetic medium.

Abstract: A waveguide including a first cladding layer, the first cladding layer having an index of refraction, n3; an assist layer, the assist layer having an index of refraction, n2, and the assist layer including ASixOy, wherein A is selected from: Ta, Ti, Nb, Hf, Zr, and Y, x is from about 0.5 to about 2.0, y is from about 3.5 to about 6.5, and the atomic ratio of A/A+Si in ASixOy is from about 0.2 to about 0.7; and a core layer, the core layer including a material having an index of refraction, n1, wherein n1 is greater than n2 and n3, and n2 is greater than n3.

Abstract: A first linearly polarized component of a signal is received. A second linearly polarized component of a signal is received, wherein the second linearly polarized signal component of a signal is orthogonal to the first linearly polarized component of a signal. The first linearly polarized component of a signal and the second linearly polarized component of a signal are down-converted to a lower frequency. A polarization correction is performed on the down-converted linearly polarized components.

Abstract: An information reproducing apparatus has a medium with a linear tracking mark extending in a scanning direction and a linear data mark extending in a direction orthogonal to the scanning direction. A light control unit irradiates the data mark with a first near-field light polarized in the scanning direction and irradiates the tracking mark with a second near-field light polarized in the direction orthogonal to the scanning direction. A detector detects light scattered by the data mark and the tracking mark irradiated with the first near-field light and the second near-field light, respectively. A signal processing unit processes a first output signal from the detector corresponding to the detected light scattered by the data mark and processes a second output signal from the detector corresponding to the detected light scattered by the tracking mark.

Abstract: An optical head device having a broadband phase plate of transforming at least three linearly polarized light beams having different wavelengths into circularly polarized light beams, is obtained. A broadband phase plate comprising two phase plates 9A and 9B laminated with e.g. an adhesive agent so that their optical axes are crossed, wherein provided that wavelengths of linearly polarized incident light beams are ?1, ?2 and ?3 (?1<?2<?3), at least one or both of the two phase plates has such a phase difference characteristics that a ratio R(?1)/R(?3) and a ratio R(?2)/R(?3) between retardation values of the wavelengths are smaller than 1 and R(?1)/R(?3) is smaller than R(?2)/R(?3), is integrated in the optical head device.

Abstract: An information reproducing apparatus has a light source for generating linearly polarized light, a medium having linear marks disposed in overlapping relation to one another, and an optical head disposed between the light source and the medium and having a fine aperture. A polarized light control portion in the light source controls the linearly polarized light to pass through the fine aperture of the optical head to generate near-field light having a preselected polarization direction and to irradiate the linear marks of the medium with the near-field light so that the preselected polarization direction of the near-field light is orthogonal to a longitudinal axis of each of the linear marks. A detector detects light scattered by the linear mark irradiated with the near-field light.

Abstract: An apparatus is provided for reproducing optical disks. An optical head irradiates linearly polarized light onto an optical disk. A change of a polarization orientation of light that is transmitted or reflected from the optical disk is detected in accordance with a recording signal on the optical disk. The apparatus moves the optical head into a pre-determined portion of the optical disk where write-once information is stored, and reproduces the write-once information after detecting a change of a polarization orientation of light that is transmitted or reflected from the pre-determined portion.

Abstract: A method for reproducing write-once information from an optical disk. The disk includes a disk substrate and a recording layer on the disk substrate, the recording layer including a magnetic film with a magnetic anisotropy in a direction perpendicular to a surface of the magnetic film. Write-once information formed by first recording areas and second recording areas is stored in a pre-determined portion of said recording layer, the first and second recording areas having different magnetic anisotropies in a direction perpendicular to a surface of the magnetic film. The method includes irradiating linearly polarized laser light onto said pre-determined portion, and detecting a rotational change in a polarization orientation of light reflected from the optical disk or light transmitted through the optical disk, the rotational change being caused depending on which of the first recording area and the second recording area is irradiated with the linearly polarized laser light.