G11B7/00

Reproducing device

A reproducing device (100) includes (i) an optical pickup (6) for irradiating, with reproduction light, an optical disk (1) which is a super-resolution medium, (ii) an RF signal processing circuit (9) for converting, into a reproduction signal, light which reflected off optical disk (1), (iii) an i-MLSE detecting section (141) for evaluating quality of the reproduction signal, and (iv) a spherical aberration correcting section (142) for correcting a spherical aberration by using a result of evaluation of the quality of the reproduction signal.

Optical disc apparatus and control method thereof
09564167 · 2017-02-07 · ·

An optical disc apparatus is disclosed. The optical disc apparatus includes: a driver configured to rotate an optical disc having a recording surface for data; an optical pick-up configured to emit a light beam to the optical disc rotated by the driver; and at least one processor configured to operate the optical pick-up to focus the light beam emitted from the pick-up unit to perform one of recording and reproducing the data on the recording surface and track curvature of the recording surface within a preset allowable range, and to process the light beam reflected from the recording surface, the at least one the processor further configured to increase the allowable range if it is determined that the focus of the light beam cannot track the curvature of the recording surface in a section of the recording surface.

Data storage device measuring resonant frequency of a shock sensor by applying differential excitation and measuring oscillation

A data storage device is disclosed comprising a disk, a head, and a shock sensor comprising a first terminal and a second terminal. A first bias signal is applied signal to the first terminal of the shock sensor and a second bias signal is applied to the second terminal of the shock sensor. An oscillating signal is generated by increasing the first bias signal and decreasing the second bias signal, and a resonant frequency of the shock sensor is detected based on the oscillating signal. A physical shock affecting the head actuated over the disk is detected based on a response of the shock sensor to the physical shock and based on the detected resonant frequency of the shock sensor.

System and method for detecting reader-writer offset in a heat-assisted magnetic recording head

An apparatus comprises a heat-assisted magnetic recording head configured to write to and read from a magnetic recording medium. The head comprises a reader and a writer including a near-field transducer (NFT). The reader comprises a center which is laterally offset relative to a center of the writer to define a reader-writer offset (RWO) therebetween. A magnetic recording medium comprises a plurality of tracks. The plurality of tracks comprises at least one track used as a region to test for a shift in the RWO. A processor is coupled to the recording head and configured to detect the RWO shift.

VOICE COIL MOTOR
20250130395 · 2025-04-24 ·

A VCM (voice coil motor) is disclosed, the VCM including: a rotor including a cylindrical bobbin for accommodating a lens and protruded at a bottom end with a boss, and a coil block arranged at a periphery of the bobbin; a stator including a magnet facing the coil block and a yoke fixing the magnet; and an elastic member including a first elastic member formed with a through hole coupled to the boss of the bobbin and a second elastic member coupled to an upper end facing the bottom end of the bobbin; wherein the boss is formed with a disengagement prevention unit inhibiting the first elastic member from being disengaged from the boss, and the first elastic member is formed with a coupling unit contacting a joint where the disengagement prevention unit and the coupling unit meet.

Concurrent modulation and frictional heating head disk contact detection

An apparatus comprises a heat-assisted magnetic recording (HAMR) head, a sensor, and a controller. The HAMR head is configured to interact with a magnetic storage medium. The sensor is configured to produce a signal indicating the occurrence of head-medium contact. The controller is configured to receive the signal and concurrently determine from the signal if the occurrence of head-medium contact is caused by a first contact detection parameter, a second contact detection parameter, or both the first and second contact detection parameters.

Light interference module and holographic storage apparatus

A light interference module includes an object lens, a first light-guiding element, and a second light-guiding element. The object lens is configured to project a signal light beam to an optical storage media. The first light-guiding element is configured to project a first reference light beam to the optical storage media, in which the first reference light beam and the signal light beam produce a first interference pattern on the optical storage media. The second light-guiding element is configured to project a second reference light beam to the optical storage media, in which the second reference light beam and the signal light beam produce a second interference pattern on the optical storage media, and the first interference pattern is different from the second interference pattern.

Multidimensional optical storage media having light confinement layers and reading methodology therefor

Described are optical recording media for recording data in voxels, the optical recording media including a plurality of data recording regions for recording the voxels, the data recording regions separated by buffer regions having optical properties such that illumination from a reader that enters one of the data recording regions remains preferentially confined in said one of the data recording regions until being scattered by interaction with one or more of the voxels. Also described are methods for reading the described optical recording media, which include separating the light received from illuminating the voxels based on wavelength, polarization, or other optical properties.

Hologram recording medium and optical element comprising the same

The present invention relates to a hologram recording medium and an optical element comprising the same. The hologram recording medium not only has excellent optical recording properties but also can exhibit transparent optical properties and excellent reliability even in high temperature and high humidity environments.

Nanostructuring from optical recording media

Devices having at least one nanostructured layer derived from a binary sequence written onto an optical medium and methods of preparing the nanostructured layers.